[RFC PATCH v2 0/13] memory-hotplug : hot-remove physical memory

[RFC PATCH v2 0/13] memory-hotplug : hot-remove physical memory

[Yasuaki Ishimatsu]

This patch series aims to support physical memory hot-remove.

  [RFC PATCH v2 1/13] memory-hotplug : rename remove_memory to offline_memory
  [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove
  [RFC PATCH v2 3/13] memory-hotplug : unify argument of firmware_map_add_early/hotplug
  [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs
  [RFC PATCH v2 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks
  [RFC PATCH v2 6/13] memory-hotplug : add memory_block_release
  [RFC PATCH v2 7/13] memory-hotplug : remove_memory calls __remove_pages
  [RFC PATCH v2 8/13] memory-hotplug : check page type in get_page_bootmem
  [RFC PATCH v2 9/13] memory-hotplug : move register_page_bootmem_info_node and put_page_bootmem for
sparse-vmemmap
  [RFC PATCH v2 10/13] memory-hotplug : implement register_page_bootmem_info_section of sparse-vmemmap
  [RFC PATCH v2 11/13] memory-hotplug : free memmap of sparse-vmemmap
  [RFC PATCH v2 12/13] memory-hotplug : add node_device_release
  [RFC PATCH v2 13/13] memory-hotplug : remove sysfs file of node

Even if you apply these patches, you cannot remove the physical memory
completely since these patches are still under development. I want you to
cooperate to improve the physical memory hot-remove. So please review these
patches and give your comment/idea.

The patches can free/remove following things:

  - acpi_memory_info                          : [RFC PATCH 2/13]
  - /sys/firmware/memmap/X/{end, start, type} : [RFC PATCH 4/13]
  - iomem_resource                            : [RFC PATCH 5/13]
  - mem_section and related sysfs files       : [RFC PATCH 6-11/13]
  - node and related sysfs files              : [RFC PATCH 12-13/13]

The patches cannot do following things yet:

  - page table of removed memory

If you find lack of function for physical memory hot-remove, please let me
know.

change log of v2:
 [RFC PATCH v2 2/13]
   * check whether memory block is offline or not before calling offline_memory()
   * check whether section is valid or not in is_memblk_offline()
   * call kobject_put() for each memory_block in is_memblk_offline()

 [RFC PATCH v2 3/13]
   * unify the end argument of firmware_map_add_early/hotplug

 [RFC PATCH v2 4/13]
   * add release_firmware_map_entry() for freeing firmware_map_entry

 [RFC PATCH v2 6/13]
  * add release_memory_block() for freeing memory_block

 [RFC PATCH v2 11/13]
  * fix wrong arguments of free_pages()

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |   16 +-
 arch/x86/mm/init_64.c                           |  144 ++++++++++++++++++++++++
 drivers/acpi/acpi_memhotplug.c                  |   28 ++++
 drivers/base/memory.c                           |   53 ++++++++
 drivers/base/node.c                             |    7 +
 drivers/firmware/memmap.c                       |   70 +++++++++++
 include/linux/firmware-map.h                    |    6 +
 include/linux/memory.h                          |    5
 include/linux/memory_hotplug.h                  |   17 --
 include/linux/mm.h                              |    5
 mm/memory_hotplug.c                             |   98 ++++++++++++----
 mm/sparse.c                                     |    5
 12 files changed, 406 insertions(+), 48 deletions(-)


--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 0/13] memory-hotplug : hot-remove physical memory

[Yasuaki Ishimatsu]

This patch series aims to support physical memory hot-remove.

  [RFC PATCH v2 1/13] memory-hotplug : rename remove_memory to offline_memory
  [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove
  [RFC PATCH v2 3/13] memory-hotplug : unify argument of firmware_map_add_early/hotplug
  [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs
  [RFC PATCH v2 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks
  [RFC PATCH v2 6/13] memory-hotplug : add memory_block_release
  [RFC PATCH v2 7/13] memory-hotplug : remove_memory calls __remove_pages
  [RFC PATCH v2 8/13] memory-hotplug : check page type in get_page_bootmem
  [RFC PATCH v2 9/13] memory-hotplug : move register_page_bootmem_info_node and put_page_bootmem for
sparse-vmemmap
  [RFC PATCH v2 10/13] memory-hotplug : implement register_page_bootmem_info_section of sparse-vmemmap
  [RFC PATCH v2 11/13] memory-hotplug : free memmap of sparse-vmemmap
  [RFC PATCH v2 12/13] memory-hotplug : add node_device_release
  [RFC PATCH v2 13/13] memory-hotplug : remove sysfs file of node

Even if you apply these patches, you cannot remove the physical memory
completely since these patches are still under development. I want you to
cooperate to improve the physical memory hot-remove. So please review these
patches and give your comment/idea.

The patches can free/remove following things:

  - acpi_memory_info                          : [RFC PATCH 2/13]
  - /sys/firmware/memmap/X/{end, start, type} : [RFC PATCH 4/13]
  - iomem_resource                            : [RFC PATCH 5/13]
  - mem_section and related sysfs files       : [RFC PATCH 6-11/13]
  - node and related sysfs files              : [RFC PATCH 12-13/13]

The patches cannot do following things yet:

  - page table of removed memory

If you find lack of function for physical memory hot-remove, please let me
know.

change log of v2:
 [RFC PATCH v2 2/13]
   * check whether memory block is offline or not before calling offline_memory()
   * check whether section is valid or not in is_memblk_offline()
   * call kobject_put() for each memory_block in is_memblk_offline()

 [RFC PATCH v2 3/13]
   * unify the end argument of firmware_map_add_early/hotplug

 [RFC PATCH v2 4/13]
   * add release_firmware_map_entry() for freeing firmware_map_entry

 [RFC PATCH v2 6/13]
  * add release_memory_block() for freeing memory_block

 [RFC PATCH v2 11/13]
  * fix wrong arguments of free_pages()

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |   16 +-
 arch/x86/mm/init_64.c                           |  144 ++++++++++++++++++++++++
 drivers/acpi/acpi_memhotplug.c                  |   28 ++++
 drivers/base/memory.c                           |   53 ++++++++
 drivers/base/node.c                             |    7 +
 drivers/firmware/memmap.c                       |   70 +++++++++++
 include/linux/firmware-map.h                    |    6 +
 include/linux/memory.h                          |    5
 include/linux/memory_hotplug.h                  |   17 --
 include/linux/mm.h                              |    5
 mm/memory_hotplug.c                             |   98 ++++++++++++----
 mm/sparse.c                                     |    5
 12 files changed, 406 insertions(+), 48 deletions(-)

[RFC PATCH v2 0/13] memory-hotplug : hot-remove physical memory

[Yasuaki Ishimatsu]

This patch series aims to support physical memory hot-remove.

  [RFC PATCH v2 1/13] memory-hotplug : rename remove_memory to offline_memory
  [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove
  [RFC PATCH v2 3/13] memory-hotplug : unify argument of firmware_map_add_early/hotplug
  [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs
  [RFC PATCH v2 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks
  [RFC PATCH v2 6/13] memory-hotplug : add memory_block_release
  [RFC PATCH v2 7/13] memory-hotplug : remove_memory calls __remove_pages
  [RFC PATCH v2 8/13] memory-hotplug : check page type in get_page_bootmem
  [RFC PATCH v2 9/13] memory-hotplug : move register_page_bootmem_info_node and put_page_bootmem for
sparse-vmemmap
  [RFC PATCH v2 10/13] memory-hotplug : implement register_page_bootmem_info_section of sparse-vmemmap
  [RFC PATCH v2 11/13] memory-hotplug : free memmap of sparse-vmemmap
  [RFC PATCH v2 12/13] memory-hotplug : add node_device_release
  [RFC PATCH v2 13/13] memory-hotplug : remove sysfs file of node

Even if you apply these patches, you cannot remove the physical memory
completely since these patches are still under development. I want you to
cooperate to improve the physical memory hot-remove. So please review these
patches and give your comment/idea.

The patches can free/remove following things:

  - acpi_memory_info                          : [RFC PATCH 2/13]
  - /sys/firmware/memmap/X/{end, start, type} : [RFC PATCH 4/13]
  - iomem_resource                            : [RFC PATCH 5/13]
  - mem_section and related sysfs files       : [RFC PATCH 6-11/13]
  - node and related sysfs files              : [RFC PATCH 12-13/13]

The patches cannot do following things yet:

  - page table of removed memory

If you find lack of function for physical memory hot-remove, please let me
know.

change log of v2:
 [RFC PATCH v2 2/13]
   * check whether memory block is offline or not before calling offline_memory()
   * check whether section is valid or not in is_memblk_offline()
   * call kobject_put() for each memory_block in is_memblk_offline()

 [RFC PATCH v2 3/13]
   * unify the end argument of firmware_map_add_early/hotplug

 [RFC PATCH v2 4/13]
   * add release_firmware_map_entry() for freeing firmware_map_entry

 [RFC PATCH v2 6/13]
  * add release_memory_block() for freeing memory_block

 [RFC PATCH v2 11/13]
  * fix wrong arguments of free_pages()

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |   16 +-
 arch/x86/mm/init_64.c                           |  144 ++++++++++++++++++++++++
 drivers/acpi/acpi_memhotplug.c                  |   28 ++++
 drivers/base/memory.c                           |   53 ++++++++
 drivers/base/node.c                             |    7 +
 drivers/firmware/memmap.c                       |   70 +++++++++++
 include/linux/firmware-map.h                    |    6 +
 include/linux/memory.h                          |    5
 include/linux/memory_hotplug.h                  |   17 --
 include/linux/mm.h                              |    5
 mm/memory_hotplug.c                             |   98 ++++++++++++----
 mm/sparse.c                                     |    5
 12 files changed, 406 insertions(+), 48 deletions(-)

[RFC PATCH v2 1/13] memory-hotplug : rename remove_memory to offline_memory

[Yasuaki Ishimatsu]

remove_memory() does not remove memory but just offlines memory. The patch
changes name of it to offline_memory().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/acpi_memhotplug.c |    2 +-
 drivers/base/memory.c          |    4 ++--
 include/linux/memory_hotplug.h |    2 +-
 mm/memory_hotplug.c            |    6 +++---
 4 files changed, 7 insertions(+), 7 deletions(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
@@ -318,7 +318,7 @@ static int acpi_memory_disable_device(st
 	 */
 	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
 		if (info->enabled) {
-			result = remove_memory(info->start_addr, info->length);
+			result = offline_memory(info->start_addr, info->length);
 			if (result)
 				return result;
 		}
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:46.095417003 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
@@ -266,8 +266,8 @@ memory_block_action(unsigned long phys_i
 			break;
 		case MEM_OFFLINE:
 			start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
-			ret = remove_memory(start_paddr,
-					    nr_pages << PAGE_SHIFT);
+			ret = offline_memory(start_paddr,
+					     nr_pages << PAGE_SHIFT);
 			break;
 		default:
 			WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
@@ -990,7 +990,7 @@ out:
 	return ret;
 }

-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
 {
 	unsigned long start_pfn, end_pfn;

@@ -999,9 +999,9 @@ int remove_memory(u64 start, u64 size)
 	return offline_pages(start_pfn, end_pfn, 120 * HZ);
 }
 #else
-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
 {
 	return -EINVAL;
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
-EXPORT_SYMBOL_GPL(remove_memory);
+EXPORT_SYMBOL_GPL(offline_memory);
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
@@ -233,7 +233,7 @@ static inline int is_mem_section_removab
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
-extern int remove_memory(u64 start, u64 size);
+extern int offline_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 								int nr_pages);
 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);

[RFC PATCH v2 1/13] memory-hotplug : rename remove_memory to offline_memory

[Yasuaki Ishimatsu]

remove_memory() does not remove memory but just offlines memory. The patch
changes name of it to offline_memory().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/acpi_memhotplug.c |    2 +-
 drivers/base/memory.c          |    4 ++--
 include/linux/memory_hotplug.h |    2 +-
 mm/memory_hotplug.c            |    6 +++---
 4 files changed, 7 insertions(+), 7 deletions(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
@@ -318,7 +318,7 @@ static int acpi_memory_disable_device(st
 	 */
 	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
 		if (info->enabled) {
-			result = remove_memory(info->start_addr, info->length);
+			result = offline_memory(info->start_addr, info->length);
 			if (result)
 				return result;
 		}
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:46.095417003 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
@@ -266,8 +266,8 @@ memory_block_action(unsigned long phys_i
 			break;
 		case MEM_OFFLINE:
 			start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
-			ret = remove_memory(start_paddr,
-					    nr_pages << PAGE_SHIFT);
+			ret = offline_memory(start_paddr,
+					     nr_pages << PAGE_SHIFT);
 			break;
 		default:
 			WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
@@ -990,7 +990,7 @@ out:
 	return ret;
 }

-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
 {
 	unsigned long start_pfn, end_pfn;

@@ -999,9 +999,9 @@ int remove_memory(u64 start, u64 size)
 	return offline_pages(start_pfn, end_pfn, 120 * HZ);
 }
 #else
-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
 {
 	return -EINVAL;
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
-EXPORT_SYMBOL_GPL(remove_memory);
+EXPORT_SYMBOL_GPL(offline_memory);
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
@@ -233,7 +233,7 @@ static inline int is_mem_section_removab
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
-extern int remove_memory(u64 start, u64 size);
+extern int offline_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 								int nr_pages);
 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);

[RFC PATCH v2 1/13] memory-hotplug : rename remove_memory to offline_memory

[Yasuaki Ishimatsu]

remove_memory() does not remove memory but just offlines memory. The patch
changes name of it to offline_memory().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/acpi_memhotplug.c |    2 +-
 drivers/base/memory.c          |    4 ++--
 include/linux/memory_hotplug.h |    2 +-
 mm/memory_hotplug.c            |    6 +++---
 4 files changed, 7 insertions(+), 7 deletions(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
@@ -318,7 +318,7 @@ static int acpi_memory_disable_device(st
 	 */
 	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
 		if (info->enabled) {
-			result = remove_memory(info->start_addr, info->length);
+			result = offline_memory(info->start_addr, info->length);
 			if (result)
 				return result;
 		}
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:46.095417003 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
@@ -266,8 +266,8 @@ memory_block_action(unsigned long phys_i
 			break;
 		case MEM_OFFLINE:
 			start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
-			ret = remove_memory(start_paddr,
-					    nr_pages << PAGE_SHIFT);
+			ret = offline_memory(start_paddr,
+					     nr_pages << PAGE_SHIFT);
 			break;
 		default:
 			WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
@@ -990,7 +990,7 @@ out:
 	return ret;
 }

-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
 {
 	unsigned long start_pfn, end_pfn;

@@ -999,9 +999,9 @@ int remove_memory(u64 start, u64 size)
 	return offline_pages(start_pfn, end_pfn, 120 * HZ);
 }
 #else
-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
 {
 	return -EINVAL;
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
-EXPORT_SYMBOL_GPL(remove_memory);
+EXPORT_SYMBOL_GPL(offline_memory);
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
@@ -233,7 +233,7 @@ static inline int is_mem_section_removab
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
-extern int remove_memory(u64 start, u64 size);
+extern int offline_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 								int nr_pages);
 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 1/13] memory-hotplug : rename remove_memory to offline_memory

[Yasuaki Ishimatsu]

remove_memory() does not remove memory but just offlines memory. The patch
changes name of it to offline_memory().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/acpi_memhotplug.c |    2 +-
 drivers/base/memory.c          |    4 ++--
 include/linux/memory_hotplug.h |    2 +-
 mm/memory_hotplug.c            |    6 +++---
 4 files changed, 7 insertions(+), 7 deletions(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
@@ -318,7 +318,7 @@ static int acpi_memory_disable_device(st
 	 */
 	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
 		if (info->enabled) {
-			result = remove_memory(info->start_addr, info->length);
+			result = offline_memory(info->start_addr, info->length);
 			if (result)
 				return result;
 		}
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:46.095417003 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
@@ -266,8 +266,8 @@ memory_block_action(unsigned long phys_i
 			break;
 		case MEM_OFFLINE:
 			start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
-			ret = remove_memory(start_paddr,
-					    nr_pages << PAGE_SHIFT);
+			ret = offline_memory(start_paddr,
+					     nr_pages << PAGE_SHIFT);
 			break;
 		default:
 			WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
@@ -990,7 +990,7 @@ out:
 	return ret;
 }

-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
 {
 	unsigned long start_pfn, end_pfn;

@@ -999,9 +999,9 @@ int remove_memory(u64 start, u64 size)
 	return offline_pages(start_pfn, end_pfn, 120 * HZ);
 }
 #else
-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
 {
 	return -EINVAL;
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
-EXPORT_SYMBOL_GPL(remove_memory);
+EXPORT_SYMBOL_GPL(offline_memory);
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
@@ -233,7 +233,7 @@ static inline int is_mem_section_removab
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
-extern int remove_memory(u64 start, u64 size);
+extern int offline_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 								int nr_pages);
 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);

[RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Yasuaki Ishimatsu]

acpi_memory_device_remove() has been prepared to remove physical memory.
But, the function only frees acpi_memory_device currentlry.

The patch adds following functions into acpi_memory_device_remove():
  - offline memory
  - remove physical memory (only return -EBUSY)
  - free acpi_memory_device

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
 drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
 include/linux/memory.h         |    5 +++++
 include/linux/memory_hotplug.h |    1 +
 mm/memory_hotplug.c            |    8 ++++++++
 5 files changed, 77 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
@@ -29,6 +29,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/memory.h>
 #include <linux/memory_hotplug.h>
 #include <linux/slab.h>
 #include <acpi/acpi_drivers.h>
@@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
 static int acpi_memory_device_remove(struct acpi_device *device, int type)
 {
 	struct acpi_memory_device *mem_device = NULL;
-
+	struct acpi_memory_info *info, *tmp;
+	int result;
+	int node;

 	if (!device || !acpi_driver_data(device))
 		return -EINVAL;

 	mem_device = acpi_driver_data(device);
+
+	node = acpi_get_node(mem_device->device->handle);
+
+	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
+		if (!info->enabled)
+			continue;
+
+		if (!is_memblk_offline(info->start_addr, info->length)) {
+			result = offline_memory(info->start_addr, info->length);
+			if (result)
+				return result;
+		}
+
+		result = remove_memory(node, info->start_addr, info->length);
+		if (result)
+			return result;
+
+		list_del(&info->list);
+		kfree(info);
+	}
+
 	kfree(mem_device);

 	return 0;
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
@@ -233,6 +233,7 @@ static inline int is_mem_section_removab
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
+extern int remove_memory(int nid, u64 start, u64 size);
 extern int offline_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 								int nr_pages);
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
@@ -659,6 +659,14 @@ out:
 }
 EXPORT_SYMBOL_GPL(add_memory);

+int remove_memory(int nid, u64 start, u64 size)
+{
+	return -EBUSY;
+
+}
+EXPORT_SYMBOL_GPL(remove_memory);
+
+
 #ifdef CONFIG_MEMORY_HOTREMOVE
 /*
  * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
@@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
 }
 EXPORT_SYMBOL(unregister_memory_isolate_notifier);

+bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	struct memory_block *mem = NULL;
+	struct mem_section *section;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pfn, section_nr;
+
+	start_pfn = PFN_DOWN(start);
+	end_pfn = start_pfn + PFN_DOWN(start);
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		section_nr = pfn_to_section_nr(pfn);
+		if (!present_section_nr(section_nr));
+			continue;
+
+		section = __nr_to_section(section_nr);
+		/* same memblock? */
+		if (mem)
+			if((section_nr >= mem->start_section_nr) &&
+			   (section_nr <= mem->end_section_nr))
+				continue;
+
+		mem = find_memory_block_hinted(section, mem);
+		if (!mem)
+			continue;
+		if (mem->state == MEM_OFFLINE) {
+			kobject_put(&mem->dev.kobj);
+			continue;
+		}
+
+		kobject_put(&mem->dev.kobj);
+		return false;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL(is_memblk_offline);
+
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
Index: linux-3.5-rc4/include/linux/memory.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
+++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
@@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
 {
 	return 0;
 }
+static inline bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	return false;
+}
 #else
 extern int register_memory_notifier(struct notifier_block *nb);
 extern void unregister_memory_notifier(struct notifier_block *nb);
@@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
 extern struct memory_block *find_memory_block_hinted(struct mem_section *,
 							struct memory_block *);
 extern struct memory_block *find_memory_block(struct mem_section *);
+extern bool is_memblk_offline(unsigned long start, unsigned long size);
 #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
 enum mem_add_context { BOOT, HOTPLUG };
 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */

[RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Yasuaki Ishimatsu]

acpi_memory_device_remove() has been prepared to remove physical memory.
But, the function only frees acpi_memory_device currentlry.

The patch adds following functions into acpi_memory_device_remove():
  - offline memory
  - remove physical memory (only return -EBUSY)
  - free acpi_memory_device

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
 drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
 include/linux/memory.h         |    5 +++++
 include/linux/memory_hotplug.h |    1 +
 mm/memory_hotplug.c            |    8 ++++++++
 5 files changed, 77 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
@@ -29,6 +29,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/memory.h>
 #include <linux/memory_hotplug.h>
 #include <linux/slab.h>
 #include <acpi/acpi_drivers.h>
@@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
 static int acpi_memory_device_remove(struct acpi_device *device, int type)
 {
 	struct acpi_memory_device *mem_device = NULL;
-
+	struct acpi_memory_info *info, *tmp;
+	int result;
+	int node;

 	if (!device || !acpi_driver_data(device))
 		return -EINVAL;

 	mem_device = acpi_driver_data(device);
+
+	node = acpi_get_node(mem_device->device->handle);
+
+	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
+		if (!info->enabled)
+			continue;
+
+		if (!is_memblk_offline(info->start_addr, info->length)) {
+			result = offline_memory(info->start_addr, info->length);
+			if (result)
+				return result;
+		}
+
+		result = remove_memory(node, info->start_addr, info->length);
+		if (result)
+			return result;
+
+		list_del(&info->list);
+		kfree(info);
+	}
+
 	kfree(mem_device);

 	return 0;
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
@@ -233,6 +233,7 @@ static inline int is_mem_section_removab
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
+extern int remove_memory(int nid, u64 start, u64 size);
 extern int offline_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 								int nr_pages);
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
@@ -659,6 +659,14 @@ out:
 }
 EXPORT_SYMBOL_GPL(add_memory);

+int remove_memory(int nid, u64 start, u64 size)
+{
+	return -EBUSY;
+
+}
+EXPORT_SYMBOL_GPL(remove_memory);
+
+
 #ifdef CONFIG_MEMORY_HOTREMOVE
 /*
  * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
@@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
 }
 EXPORT_SYMBOL(unregister_memory_isolate_notifier);

+bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	struct memory_block *mem = NULL;
+	struct mem_section *section;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pfn, section_nr;
+
+	start_pfn = PFN_DOWN(start);
+	end_pfn = start_pfn + PFN_DOWN(start);
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		section_nr = pfn_to_section_nr(pfn);
+		if (!present_section_nr(section_nr));
+			continue;
+
+		section = __nr_to_section(section_nr);
+		/* same memblock? */
+		if (mem)
+			if((section_nr >= mem->start_section_nr) &&
+			   (section_nr <= mem->end_section_nr))
+				continue;
+
+		mem = find_memory_block_hinted(section, mem);
+		if (!mem)
+			continue;
+		if (mem->state == MEM_OFFLINE) {
+			kobject_put(&mem->dev.kobj);
+			continue;
+		}
+
+		kobject_put(&mem->dev.kobj);
+		return false;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL(is_memblk_offline);
+
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
Index: linux-3.5-rc4/include/linux/memory.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
+++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
@@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
 {
 	return 0;
 }
+static inline bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	return false;
+}
 #else
 extern int register_memory_notifier(struct notifier_block *nb);
 extern void unregister_memory_notifier(struct notifier_block *nb);
@@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
 extern struct memory_block *find_memory_block_hinted(struct mem_section *,
 							struct memory_block *);
 extern struct memory_block *find_memory_block(struct mem_section *);
+extern bool is_memblk_offline(unsigned long start, unsigned long size);
 #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
 enum mem_add_context { BOOT, HOTPLUG };
 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */

[RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Yasuaki Ishimatsu]

acpi_memory_device_remove() has been prepared to remove physical memory.
But, the function only frees acpi_memory_device currentlry.

The patch adds following functions into acpi_memory_device_remove():
  - offline memory
  - remove physical memory (only return -EBUSY)
  - free acpi_memory_device

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
 drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
 include/linux/memory.h         |    5 +++++
 include/linux/memory_hotplug.h |    1 +
 mm/memory_hotplug.c            |    8 ++++++++
 5 files changed, 77 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
@@ -29,6 +29,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/memory.h>
 #include <linux/memory_hotplug.h>
 #include <linux/slab.h>
 #include <acpi/acpi_drivers.h>
@@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
 static int acpi_memory_device_remove(struct acpi_device *device, int type)
 {
 	struct acpi_memory_device *mem_device = NULL;
-
+	struct acpi_memory_info *info, *tmp;
+	int result;
+	int node;

 	if (!device || !acpi_driver_data(device))
 		return -EINVAL;

 	mem_device = acpi_driver_data(device);
+
+	node = acpi_get_node(mem_device->device->handle);
+
+	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
+		if (!info->enabled)
+			continue;
+
+		if (!is_memblk_offline(info->start_addr, info->length)) {
+			result = offline_memory(info->start_addr, info->length);
+			if (result)
+				return result;
+		}
+
+		result = remove_memory(node, info->start_addr, info->length);
+		if (result)
+			return result;
+
+		list_del(&info->list);
+		kfree(info);
+	}
+
 	kfree(mem_device);

 	return 0;
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
@@ -233,6 +233,7 @@ static inline int is_mem_section_removab
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
+extern int remove_memory(int nid, u64 start, u64 size);
 extern int offline_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 								int nr_pages);
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
@@ -659,6 +659,14 @@ out:
 }
 EXPORT_SYMBOL_GPL(add_memory);

+int remove_memory(int nid, u64 start, u64 size)
+{
+	return -EBUSY;
+
+}
+EXPORT_SYMBOL_GPL(remove_memory);
+
+
 #ifdef CONFIG_MEMORY_HOTREMOVE
 /*
  * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
@@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
 }
 EXPORT_SYMBOL(unregister_memory_isolate_notifier);

+bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	struct memory_block *mem = NULL;
+	struct mem_section *section;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pfn, section_nr;
+
+	start_pfn = PFN_DOWN(start);
+	end_pfn = start_pfn + PFN_DOWN(start);
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		section_nr = pfn_to_section_nr(pfn);
+		if (!present_section_nr(section_nr));
+			continue;
+
+		section = __nr_to_section(section_nr);
+		/* same memblock? */
+		if (mem)
+			if((section_nr >= mem->start_section_nr) &&
+			   (section_nr <= mem->end_section_nr))
+				continue;
+
+		mem = find_memory_block_hinted(section, mem);
+		if (!mem)
+			continue;
+		if (mem->state == MEM_OFFLINE) {
+			kobject_put(&mem->dev.kobj);
+			continue;
+		}
+
+		kobject_put(&mem->dev.kobj);
+		return false;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL(is_memblk_offline);
+
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
Index: linux-3.5-rc4/include/linux/memory.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
+++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
@@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
 {
 	return 0;
 }
+static inline bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	return false;
+}
 #else
 extern int register_memory_notifier(struct notifier_block *nb);
 extern void unregister_memory_notifier(struct notifier_block *nb);
@@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
 extern struct memory_block *find_memory_block_hinted(struct mem_section *,
 							struct memory_block *);
 extern struct memory_block *find_memory_block(struct mem_section *);
+extern bool is_memblk_offline(unsigned long start, unsigned long size);
 #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
 enum mem_add_context { BOOT, HOTPLUG };
 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Yasuaki Ishimatsu]

acpi_memory_device_remove() has been prepared to remove physical memory.
But, the function only frees acpi_memory_device currentlry.

The patch adds following functions into acpi_memory_device_remove():
  - offline memory
  - remove physical memory (only return -EBUSY)
  - free acpi_memory_device

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
 drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
 include/linux/memory.h         |    5 +++++
 include/linux/memory_hotplug.h |    1 +
 mm/memory_hotplug.c            |    8 ++++++++
 5 files changed, 77 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
@@ -29,6 +29,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/memory.h>
 #include <linux/memory_hotplug.h>
 #include <linux/slab.h>
 #include <acpi/acpi_drivers.h>
@@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
 static int acpi_memory_device_remove(struct acpi_device *device, int type)
 {
 	struct acpi_memory_device *mem_device = NULL;
-
+	struct acpi_memory_info *info, *tmp;
+	int result;
+	int node;

 	if (!device || !acpi_driver_data(device))
 		return -EINVAL;

 	mem_device = acpi_driver_data(device);
+
+	node = acpi_get_node(mem_device->device->handle);
+
+	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
+		if (!info->enabled)
+			continue;
+
+		if (!is_memblk_offline(info->start_addr, info->length)) {
+			result = offline_memory(info->start_addr, info->length);
+			if (result)
+				return result;
+		}
+
+		result = remove_memory(node, info->start_addr, info->length);
+		if (result)
+			return result;
+
+		list_del(&info->list);
+		kfree(info);
+	}
+
 	kfree(mem_device);

 	return 0;
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
@@ -233,6 +233,7 @@ static inline int is_mem_section_removab
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
+extern int remove_memory(int nid, u64 start, u64 size);
 extern int offline_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 								int nr_pages);
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
@@ -659,6 +659,14 @@ out:
 }
 EXPORT_SYMBOL_GPL(add_memory);

+int remove_memory(int nid, u64 start, u64 size)
+{
+	return -EBUSY;
+
+}
+EXPORT_SYMBOL_GPL(remove_memory);
+
+
 #ifdef CONFIG_MEMORY_HOTREMOVE
 /*
  * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
@@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
 }
 EXPORT_SYMBOL(unregister_memory_isolate_notifier);

+bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	struct memory_block *mem = NULL;
+	struct mem_section *section;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pfn, section_nr;
+
+	start_pfn = PFN_DOWN(start);
+	end_pfn = start_pfn + PFN_DOWN(start);
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		section_nr = pfn_to_section_nr(pfn);
+		if (!present_section_nr(section_nr));
+			continue;
+
+		section = __nr_to_section(section_nr);
+		/* same memblock? */
+		if (mem)
+			if((section_nr >= mem->start_section_nr) &&
+			   (section_nr <= mem->end_section_nr))
+				continue;
+
+		mem = find_memory_block_hinted(section, mem);
+		if (!mem)
+			continue;
+		if (mem->state == MEM_OFFLINE) {
+			kobject_put(&mem->dev.kobj);
+			continue;
+		}
+
+		kobject_put(&mem->dev.kobj);
+		return false;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL(is_memblk_offline);
+
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
Index: linux-3.5-rc4/include/linux/memory.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
+++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
@@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
 {
 	return 0;
 }
+static inline bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	return false;
+}
 #else
 extern int register_memory_notifier(struct notifier_block *nb);
 extern void unregister_memory_notifier(struct notifier_block *nb);
@@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
 extern struct memory_block *find_memory_block_hinted(struct mem_section *,
 							struct memory_block *);
 extern struct memory_block *find_memory_block(struct mem_section *);
+extern bool is_memblk_offline(unsigned long start, unsigned long size);
 #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
 enum mem_add_context { BOOT, HOTPLUG };
 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */

[RFC PATCH v2 3/13] unify argument of firmware_map_add_early/hotplug

[Yasuaki Ishimatsu]

There are two ways to create /sys/firmware/memmap/X sysfs:

  - firmware_map_add_early
    When the system starts, it is calledd from e820_reserve_resources()
  - firmware_map_add_hotplug
    When the memory is hot plugged, it is called from add_memory()

But these functions are called without unifying value of end argument as below:

  - end argument of firmware_map_add_early()   : start + size - 1
  - end argument of firmware_map_add_hogplug() : start + size

The patch unifies them to "start + size - 1".

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
@@ -642,7 +642,7 @@ int __ref add_memory(int nid, u64 start,
 	}

 	/* create new memmap entry */
-	firmware_map_add_hotplug(start, start + size, "System RAM");
+	firmware_map_add_hotplug(start, start + size - 1, "System RAM");

 	goto out;

[RFC PATCH v2 3/13] unify argument of firmware_map_add_early/hotplug

[Yasuaki Ishimatsu]

There are two ways to create /sys/firmware/memmap/X sysfs:

  - firmware_map_add_early
    When the system starts, it is calledd from e820_reserve_resources()
  - firmware_map_add_hotplug
    When the memory is hot plugged, it is called from add_memory()

But these functions are called without unifying value of end argument as below:

  - end argument of firmware_map_add_early()   : start + size - 1
  - end argument of firmware_map_add_hogplug() : start + size

The patch unifies them to "start + size - 1".

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
@@ -642,7 +642,7 @@ int __ref add_memory(int nid, u64 start,
 	}

 	/* create new memmap entry */
-	firmware_map_add_hotplug(start, start + size, "System RAM");
+	firmware_map_add_hotplug(start, start + size - 1, "System RAM");

 	goto out;

[RFC PATCH v2 3/13] unify argument of firmware_map_add_early/hotplug

[Yasuaki Ishimatsu]

There are two ways to create /sys/firmware/memmap/X sysfs:

  - firmware_map_add_early
    When the system starts, it is calledd from e820_reserve_resources()
  - firmware_map_add_hotplug
    When the memory is hot plugged, it is called from add_memory()

But these functions are called without unifying value of end argument as below:

  - end argument of firmware_map_add_early()   : start + size - 1
  - end argument of firmware_map_add_hogplug() : start + size

The patch unifies them to "start + size - 1".

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
@@ -642,7 +642,7 @@ int __ref add_memory(int nid, u64 start,
 	}

 	/* create new memmap entry */
-	firmware_map_add_hotplug(start, start + size, "System RAM");
+	firmware_map_add_hotplug(start, start + size - 1, "System RAM");

 	goto out;


--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 3/13] unify argument of firmware_map_add_early/hotplug

[Yasuaki Ishimatsu]

There are two ways to create /sys/firmware/memmap/X sysfs:

  - firmware_map_add_early
    When the system starts, it is calledd from e820_reserve_resources()
  - firmware_map_add_hotplug
    When the memory is hot plugged, it is called from add_memory()

But these functions are called without unifying value of end argument as below:

  - end argument of firmware_map_add_early()   : start + size - 1
  - end argument of firmware_map_add_hogplug() : start + size

The patch unifies them to "start + size - 1".

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
@@ -642,7 +642,7 @@ int __ref add_memory(int nid, u64 start,
 	}

 	/* create new memmap entry */
-	firmware_map_add_hotplug(start, start + size, "System RAM");
+	firmware_map_add_hotplug(start, start + size - 1, "System RAM");

 	goto out;

[RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
sysfs files are created. But there is no code to remove these files. The patch
implements the function to remove them.

Note : The code does not free firmware_map_entry since there is no way to free
       memory which is allocated by bootmem.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/firmware-map.h |    6 +++
 mm/memory_hotplug.c          |    6 +++
 3 files changed, 81 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
@@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);

 int remove_memory(int nid, u64 start, u64 size)
 {
-	return -EBUSY;
+	lock_memory_hotplug();
+	/* remove memmap entry */
+	firmware_map_remove(start, start + size - 1, "System RAM");
+	unlock_memory_hotplug();
+	return 0;

 }
 EXPORT_SYMBOL_GPL(remove_memory);
Index: linux-3.5-rc4/include/linux/firmware-map.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
+++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
@@ -25,6 +25,7 @@

 int firmware_map_add_early(u64 start, u64 end, const char *type);
 int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
+int firmware_map_remove(u64 start, u64 end, const char *type);

 #else /* CONFIG_FIRMWARE_MEMMAP */

@@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
 	return 0;
 }

+static inline int firmware_map_remove(u64 start, u64 end, const char *type)
+{
+	return 0;
+}
+
 #endif /* CONFIG_FIRMWARE_MEMMAP */

 #endif /* _LINUX_FIRMWARE_MAP_H */
Index: linux-3.5-rc4/drivers/firmware/memmap.c
===================================================================
--- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
+++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
@@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
 	.show = memmap_attr_show,
 };

+static void release_firmware_map_entry(struct kobject *kobj)
+{
+	/*
+	 * FIXME : There is no idea.
+	 *         How to free the entry which allocated bootmem?
+	 */
+}
+
 static struct kobj_type memmap_ktype = {
+	.release	= release_firmware_map_entry,
 	.sysfs_ops	= &memmap_attr_ops,
 	.default_attrs	= def_attrs,
 };
@@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
 	return 0;
 }

+/**
+ * firmware_map_remove_entry() - Does the real work to remove a firmware
+ * memmap entry.
+ * @entry: removed entry.
+ **/
+static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
+{
+	list_del(&entry->list);
+}
+
 /*
  * Add memmap entry on sysfs
  */
@@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
 	return 0;
 }

+/*
+ * Remove memmap entry on sysfs
+ */
+static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
+{
+	kobject_put(&entry->kobj);
+}
+
+/*
+ * Search memmap entry
+ */
+
+struct firmware_map_entry * __meminit
+find_firmware_map_entry(u64 start, u64 end, const char *type)
+{
+	struct firmware_map_entry *entry;
+
+	list_for_each_entry(entry, &map_entries, list)
+		if ((entry->start == start) && (entry->end == end) &&
+		    (!strcmp(entry->type, type)))
+			return entry;
+
+	return NULL;
+}
+
 /**
  * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
  * memory hotplug.
@@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
 	return firmware_map_add_entry(start, end, type, entry);
 }

+/**
+ * firmware_map_remove() - remove a firmware mapping entry
+ * @start: Start of the memory range.
+ * @end:   End of the memory range (inclusive).
+ * @type:  Type of the memory range.
+ *
+ * removes a firmware mapping entry.
+ *
+ * Returns 0 on success, or -EINVAL if no entry.
+ **/
+int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
+{
+	struct firmware_map_entry *entry;
+
+	entry = find_firmware_map_entry(start, end, type);
+	if (!entry)
+		return -EINVAL;
+
+	/* remove the memmap entry */
+	remove_sysfs_fw_map_entry(entry);
+
+	firmware_map_remove_entry(entry);
+
+	return 0;
+}
+
 /*
  * Sysfs functions -------------------------------------------------------------
  */

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
sysfs files are created. But there is no code to remove these files. The patch
implements the function to remove them.

Note : The code does not free firmware_map_entry since there is no way to free
       memory which is allocated by bootmem.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/firmware-map.h |    6 +++
 mm/memory_hotplug.c          |    6 +++
 3 files changed, 81 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
@@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);

 int remove_memory(int nid, u64 start, u64 size)
 {
-	return -EBUSY;
+	lock_memory_hotplug();
+	/* remove memmap entry */
+	firmware_map_remove(start, start + size - 1, "System RAM");
+	unlock_memory_hotplug();
+	return 0;

 }
 EXPORT_SYMBOL_GPL(remove_memory);
Index: linux-3.5-rc4/include/linux/firmware-map.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
+++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
@@ -25,6 +25,7 @@

 int firmware_map_add_early(u64 start, u64 end, const char *type);
 int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
+int firmware_map_remove(u64 start, u64 end, const char *type);

 #else /* CONFIG_FIRMWARE_MEMMAP */

@@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
 	return 0;
 }

+static inline int firmware_map_remove(u64 start, u64 end, const char *type)
+{
+	return 0;
+}
+
 #endif /* CONFIG_FIRMWARE_MEMMAP */

 #endif /* _LINUX_FIRMWARE_MAP_H */
Index: linux-3.5-rc4/drivers/firmware/memmap.c
===================================================================
--- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
+++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
@@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
 	.show = memmap_attr_show,
 };

+static void release_firmware_map_entry(struct kobject *kobj)
+{
+	/*
+	 * FIXME : There is no idea.
+	 *         How to free the entry which allocated bootmem?
+	 */
+}
+
 static struct kobj_type memmap_ktype = {
+	.release	= release_firmware_map_entry,
 	.sysfs_ops	= &memmap_attr_ops,
 	.default_attrs	= def_attrs,
 };
@@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
 	return 0;
 }

+/**
+ * firmware_map_remove_entry() - Does the real work to remove a firmware
+ * memmap entry.
+ * @entry: removed entry.
+ **/
+static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
+{
+	list_del(&entry->list);
+}
+
 /*
  * Add memmap entry on sysfs
  */
@@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
 	return 0;
 }

+/*
+ * Remove memmap entry on sysfs
+ */
+static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
+{
+	kobject_put(&entry->kobj);
+}
+
+/*
+ * Search memmap entry
+ */
+
+struct firmware_map_entry * __meminit
+find_firmware_map_entry(u64 start, u64 end, const char *type)
+{
+	struct firmware_map_entry *entry;
+
+	list_for_each_entry(entry, &map_entries, list)
+		if ((entry->start == start) && (entry->end == end) &&
+		    (!strcmp(entry->type, type)))
+			return entry;
+
+	return NULL;
+}
+
 /**
  * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
  * memory hotplug.
@@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
 	return firmware_map_add_entry(start, end, type, entry);
 }

+/**
+ * firmware_map_remove() - remove a firmware mapping entry
+ * @start: Start of the memory range.
+ * @end:   End of the memory range (inclusive).
+ * @type:  Type of the memory range.
+ *
+ * removes a firmware mapping entry.
+ *
+ * Returns 0 on success, or -EINVAL if no entry.
+ **/
+int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
+{
+	struct firmware_map_entry *entry;
+
+	entry = find_firmware_map_entry(start, end, type);
+	if (!entry)
+		return -EINVAL;
+
+	/* remove the memmap entry */
+	remove_sysfs_fw_map_entry(entry);
+
+	firmware_map_remove_entry(entry);
+
+	return 0;
+}
+
 /*
  * Sysfs functions -------------------------------------------------------------
  */

[RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
sysfs files are created. But there is no code to remove these files. The patch
implements the function to remove them.

Note : The code does not free firmware_map_entry since there is no way to free
       memory which is allocated by bootmem.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/firmware-map.h |    6 +++
 mm/memory_hotplug.c          |    6 +++
 3 files changed, 81 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
@@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);

 int remove_memory(int nid, u64 start, u64 size)
 {
-	return -EBUSY;
+	lock_memory_hotplug();
+	/* remove memmap entry */
+	firmware_map_remove(start, start + size - 1, "System RAM");
+	unlock_memory_hotplug();
+	return 0;

 }
 EXPORT_SYMBOL_GPL(remove_memory);
Index: linux-3.5-rc4/include/linux/firmware-map.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
+++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
@@ -25,6 +25,7 @@

 int firmware_map_add_early(u64 start, u64 end, const char *type);
 int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
+int firmware_map_remove(u64 start, u64 end, const char *type);

 #else /* CONFIG_FIRMWARE_MEMMAP */

@@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
 	return 0;
 }

+static inline int firmware_map_remove(u64 start, u64 end, const char *type)
+{
+	return 0;
+}
+
 #endif /* CONFIG_FIRMWARE_MEMMAP */

 #endif /* _LINUX_FIRMWARE_MAP_H */
Index: linux-3.5-rc4/drivers/firmware/memmap.c
===================================================================
--- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
+++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
@@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
 	.show = memmap_attr_show,
 };

+static void release_firmware_map_entry(struct kobject *kobj)
+{
+	/*
+	 * FIXME : There is no idea.
+	 *         How to free the entry which allocated bootmem?
+	 */
+}
+
 static struct kobj_type memmap_ktype = {
+	.release	= release_firmware_map_entry,
 	.sysfs_ops	= &memmap_attr_ops,
 	.default_attrs	= def_attrs,
 };
@@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
 	return 0;
 }

+/**
+ * firmware_map_remove_entry() - Does the real work to remove a firmware
+ * memmap entry.
+ * @entry: removed entry.
+ **/
+static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
+{
+	list_del(&entry->list);
+}
+
 /*
  * Add memmap entry on sysfs
  */
@@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
 	return 0;
 }

+/*
+ * Remove memmap entry on sysfs
+ */
+static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
+{
+	kobject_put(&entry->kobj);
+}
+
+/*
+ * Search memmap entry
+ */
+
+struct firmware_map_entry * __meminit
+find_firmware_map_entry(u64 start, u64 end, const char *type)
+{
+	struct firmware_map_entry *entry;
+
+	list_for_each_entry(entry, &map_entries, list)
+		if ((entry->start == start) && (entry->end == end) &&
+		    (!strcmp(entry->type, type)))
+			return entry;
+
+	return NULL;
+}
+
 /**
  * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
  * memory hotplug.
@@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
 	return firmware_map_add_entry(start, end, type, entry);
 }

+/**
+ * firmware_map_remove() - remove a firmware mapping entry
+ * @start: Start of the memory range.
+ * @end:   End of the memory range (inclusive).
+ * @type:  Type of the memory range.
+ *
+ * removes a firmware mapping entry.
+ *
+ * Returns 0 on success, or -EINVAL if no entry.
+ **/
+int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
+{
+	struct firmware_map_entry *entry;
+
+	entry = find_firmware_map_entry(start, end, type);
+	if (!entry)
+		return -EINVAL;
+
+	/* remove the memmap entry */
+	remove_sysfs_fw_map_entry(entry);
+
+	firmware_map_remove_entry(entry);
+
+	return 0;
+}
+
 /*
  * Sysfs functions -------------------------------------------------------------
  */

[RFC PATCH v2 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks

[Yasuaki Ishimatsu]

Since applying a patch(de7f0cba96786c), release_mem_region() has been changed
as called in PAGES_PER_SECTION chunks because register_memory_resource() is
called in PAGES_PER_SECTION chunks by add_memory(). But it seems firmware
dependency. If CRS are written in the PAGES_PER_SECTION chunks in ACPI DSDT
Table, register_memory_resource() is called in PAGES_PER_SECTION chunks.
But if CRS are written in the DIMM unit in ACPI DSDT Table,
register_memory_resource() is called in DIMM unit. So release_mem_region()
should not be called in PAGES_PER_SECTION chunks. The patch fixes it.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |   13 +++++++++----
 mm/memory_hotplug.c                             |    4 ++--
 2 files changed, 11 insertions(+), 6 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:05.919169458 +0900
@@ -358,11 +358,11 @@ int __remove_pages(struct zone *zone, un
 	BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
 	BUG_ON(nr_pages % PAGES_PER_SECTION);

+	release_mem_region(phys_start_pfn << PAGE_SHIFT,  nr_pages * PAGE_SIZE);
+
 	sections_to_remove = nr_pages / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
-		release_mem_region(pfn << PAGE_SHIFT,
-				   PAGES_PER_SECTION << PAGE_SHIFT);
 		ret = __remove_section(zone, __pfn_to_section(pfn));
 		if (ret)
 			break;
Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c
===================================================================
--- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:21:45.641422678
+0900
+++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:05.920169437 +0900
@@ -77,7 +77,8 @@ static int pseries_remove_memblock(unsig
 {
 	unsigned long start, start_pfn;
 	struct zone *zone;
-	int ret;
+	int i, ret;
+	int sections_to_remove;

 	start_pfn = base >> PAGE_SHIFT;

@@ -97,9 +98,13 @@ static int pseries_remove_memblock(unsig
 	 * to sysfs "state" file and we can't remove sysfs entries
 	 * while writing to it. So we have to defer it to here.
 	 */
-	ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT);
-	if (ret)
-		return ret;
+	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
+	for (i = 0; i < sections_to_remove; i++) {
+		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
+		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
+		if (ret)
+			return ret;
+	}

 	/*
 	 * Update memory regions for memory remove

[RFC PATCH v2 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks

[Yasuaki Ishimatsu]

Since applying a patch(de7f0cba96786c), release_mem_region() has been changed
as called in PAGES_PER_SECTION chunks because register_memory_resource() is
called in PAGES_PER_SECTION chunks by add_memory(). But it seems firmware
dependency. If CRS are written in the PAGES_PER_SECTION chunks in ACPI DSDT
Table, register_memory_resource() is called in PAGES_PER_SECTION chunks.
But if CRS are written in the DIMM unit in ACPI DSDT Table,
register_memory_resource() is called in DIMM unit. So release_mem_region()
should not be called in PAGES_PER_SECTION chunks. The patch fixes it.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |   13 +++++++++----
 mm/memory_hotplug.c                             |    4 ++--
 2 files changed, 11 insertions(+), 6 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:05.919169458 +0900
@@ -358,11 +358,11 @@ int __remove_pages(struct zone *zone, un
 	BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
 	BUG_ON(nr_pages % PAGES_PER_SECTION);

+	release_mem_region(phys_start_pfn << PAGE_SHIFT,  nr_pages * PAGE_SIZE);
+
 	sections_to_remove = nr_pages / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
-		release_mem_region(pfn << PAGE_SHIFT,
-				   PAGES_PER_SECTION << PAGE_SHIFT);
 		ret = __remove_section(zone, __pfn_to_section(pfn));
 		if (ret)
 			break;
Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c
===================================================================
--- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:21:45.641422678
+0900
+++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:05.920169437 +0900
@@ -77,7 +77,8 @@ static int pseries_remove_memblock(unsig
 {
 	unsigned long start, start_pfn;
 	struct zone *zone;
-	int ret;
+	int i, ret;
+	int sections_to_remove;

 	start_pfn = base >> PAGE_SHIFT;

@@ -97,9 +98,13 @@ static int pseries_remove_memblock(unsig
 	 * to sysfs "state" file and we can't remove sysfs entries
 	 * while writing to it. So we have to defer it to here.
 	 */
-	ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT);
-	if (ret)
-		return ret;
+	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
+	for (i = 0; i < sections_to_remove; i++) {
+		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
+		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
+		if (ret)
+			return ret;
+	}

 	/*
 	 * Update memory regions for memory remove

[RFC PATCH v2 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks

[Yasuaki Ishimatsu]

Since applying a patch(de7f0cba96786c), release_mem_region() has been changed
as called in PAGES_PER_SECTION chunks because register_memory_resource() is
called in PAGES_PER_SECTION chunks by add_memory(). But it seems firmware
dependency. If CRS are written in the PAGES_PER_SECTION chunks in ACPI DSDT
Table, register_memory_resource() is called in PAGES_PER_SECTION chunks.
But if CRS are written in the DIMM unit in ACPI DSDT Table,
register_memory_resource() is called in DIMM unit. So release_mem_region()
should not be called in PAGES_PER_SECTION chunks. The patch fixes it.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |   13 +++++++++----
 mm/memory_hotplug.c                             |    4 ++--
 2 files changed, 11 insertions(+), 6 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:05.919169458 +0900
@@ -358,11 +358,11 @@ int __remove_pages(struct zone *zone, un
 	BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
 	BUG_ON(nr_pages % PAGES_PER_SECTION);

+	release_mem_region(phys_start_pfn << PAGE_SHIFT,  nr_pages * PAGE_SIZE);
+
 	sections_to_remove = nr_pages / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
-		release_mem_region(pfn << PAGE_SHIFT,
-				   PAGES_PER_SECTION << PAGE_SHIFT);
 		ret = __remove_section(zone, __pfn_to_section(pfn));
 		if (ret)
 			break;
Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c
===================================================================
--- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:21:45.641422678
+0900
+++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:05.920169437 +0900
@@ -77,7 +77,8 @@ static int pseries_remove_memblock(unsig
 {
 	unsigned long start, start_pfn;
 	struct zone *zone;
-	int ret;
+	int i, ret;
+	int sections_to_remove;

 	start_pfn = base >> PAGE_SHIFT;

@@ -97,9 +98,13 @@ static int pseries_remove_memblock(unsig
 	 * to sysfs "state" file and we can't remove sysfs entries
 	 * while writing to it. So we have to defer it to here.
 	 */
-	ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT);
-	if (ret)
-		return ret;
+	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
+	for (i = 0; i < sections_to_remove; i++) {
+		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
+		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
+		if (ret)
+			return ret;
+	}

 	/*
 	 * Update memory regions for memory remove

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks

[Yasuaki Ishimatsu]

Since applying a patch(de7f0cba96786c), release_mem_region() has been changed
as called in PAGES_PER_SECTION chunks because register_memory_resource() is
called in PAGES_PER_SECTION chunks by add_memory(). But it seems firmware
dependency. If CRS are written in the PAGES_PER_SECTION chunks in ACPI DSDT
Table, register_memory_resource() is called in PAGES_PER_SECTION chunks.
But if CRS are written in the DIMM unit in ACPI DSDT Table,
register_memory_resource() is called in DIMM unit. So release_mem_region()
should not be called in PAGES_PER_SECTION chunks. The patch fixes it.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |   13 +++++++++----
 mm/memory_hotplug.c                             |    4 ++--
 2 files changed, 11 insertions(+), 6 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:05.919169458 +0900
@@ -358,11 +358,11 @@ int __remove_pages(struct zone *zone, un
 	BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
 	BUG_ON(nr_pages % PAGES_PER_SECTION);

+	release_mem_region(phys_start_pfn << PAGE_SHIFT,  nr_pages * PAGE_SIZE);
+
 	sections_to_remove = nr_pages / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
-		release_mem_region(pfn << PAGE_SHIFT,
-				   PAGES_PER_SECTION << PAGE_SHIFT);
 		ret = __remove_section(zone, __pfn_to_section(pfn));
 		if (ret)
 			break;
Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c
===================================================================
--- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:21:45.641422678
+0900
+++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:05.920169437 +0900
@@ -77,7 +77,8 @@ static int pseries_remove_memblock(unsig
 {
 	unsigned long start, start_pfn;
 	struct zone *zone;
-	int ret;
+	int i, ret;
+	int sections_to_remove;

 	start_pfn = base >> PAGE_SHIFT;

@@ -97,9 +98,13 @@ static int pseries_remove_memblock(unsig
 	 * to sysfs "state" file and we can't remove sysfs entries
 	 * while writing to it. So we have to defer it to here.
 	 */
-	ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT);
-	if (ret)
-		return ret;
+	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
+	for (i = 0; i < sections_to_remove; i++) {
+		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
+		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
+		if (ret)
+			return ret;
+	}

 	/*
 	 * Update memory regions for memory remove

[RFC PATCH v2 6/13] memory-hotplug : add memory_block_release

[Yasuaki Ishimatsu]

When calling remove_memory_block(), the function shows following message at
device_release().

Device 'memory528' does not have a release() function, it is broken and must
be fixed.

remove_memory_block() calls kfree(mem). I think it shouled be called from
device_release(). So the patch implements memory_block_release()

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/base/memory.c |   11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:22:08.094141981 +0900
@@ -108,6 +108,15 @@ bool is_memblk_offline(unsigned long sta
 }
 EXPORT_SYMBOL(is_memblk_offline);

+#define to_memory_block(device) container_of(device, struct memory_block, dev)
+
+static void release_memory_block(struct device *dev)
+{
+	struct memory_block *mem = to_memory_block(dev);
+
+	kfree(mem);
+}
+
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
@@ -118,6 +127,7 @@ int register_memory(struct memory_block

 	memory->dev.bus = &memory_subsys;
 	memory->dev.id = memory->start_section_nr / sections_per_block;
+	memory->dev.release = release_memory_block;

 	error = device_register(&memory->dev);
 	return error;
@@ -668,7 +678,6 @@ int remove_memory_block(unsigned long no
 		mem_remove_simple_file(mem, phys_device);
 		mem_remove_simple_file(mem, removable);
 		unregister_memory(mem);
-		kfree(mem);
 	} else
 		kobject_put(&mem->dev.kobj);


--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 6/13] memory-hotplug : add memory_block_release

[Yasuaki Ishimatsu]

When calling remove_memory_block(), the function shows following message at
device_release().

Device 'memory528' does not have a release() function, it is broken and must
be fixed.

remove_memory_block() calls kfree(mem). I think it shouled be called from
device_release(). So the patch implements memory_block_release()

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/base/memory.c |   11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:22:08.094141981 +0900
@@ -108,6 +108,15 @@ bool is_memblk_offline(unsigned long sta
 }
 EXPORT_SYMBOL(is_memblk_offline);

+#define to_memory_block(device) container_of(device, struct memory_block, dev)
+
+static void release_memory_block(struct device *dev)
+{
+	struct memory_block *mem = to_memory_block(dev);
+
+	kfree(mem);
+}
+
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
@@ -118,6 +127,7 @@ int register_memory(struct memory_block

 	memory->dev.bus = &memory_subsys;
 	memory->dev.id = memory->start_section_nr / sections_per_block;
+	memory->dev.release = release_memory_block;

 	error = device_register(&memory->dev);
 	return error;
@@ -668,7 +678,6 @@ int remove_memory_block(unsigned long no
 		mem_remove_simple_file(mem, phys_device);
 		mem_remove_simple_file(mem, removable);
 		unregister_memory(mem);
-		kfree(mem);
 	} else
 		kobject_put(&mem->dev.kobj);

[RFC PATCH v2 6/13] memory-hotplug : add memory_block_release

[Yasuaki Ishimatsu]

When calling remove_memory_block(), the function shows following message at
device_release().

Device 'memory528' does not have a release() function, it is broken and must
be fixed.

remove_memory_block() calls kfree(mem). I think it shouled be called from
device_release(). So the patch implements memory_block_release()

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/base/memory.c |   11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
+++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:22:08.094141981 +0900
@@ -108,6 +108,15 @@ bool is_memblk_offline(unsigned long sta
 }
 EXPORT_SYMBOL(is_memblk_offline);

+#define to_memory_block(device) container_of(device, struct memory_block, dev)
+
+static void release_memory_block(struct device *dev)
+{
+	struct memory_block *mem = to_memory_block(dev);
+
+	kfree(mem);
+}
+
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
@@ -118,6 +127,7 @@ int register_memory(struct memory_block

 	memory->dev.bus = &memory_subsys;
 	memory->dev.id = memory->start_section_nr / sections_per_block;
+	memory->dev.release = release_memory_block;

 	error = device_register(&memory->dev);
 	return error;
@@ -668,7 +678,6 @@ int remove_memory_block(unsigned long no
 		mem_remove_simple_file(mem, phys_device);
 		mem_remove_simple_file(mem, removable);
 		unregister_memory(mem);
-		kfree(mem);
 	} else
 		kobject_put(&mem->dev.kobj);

[RFC PATCH v2 7/13] memory-hotplug : remove_memory calls __remove_pages

[Yasuaki Ishimatsu]

The patch adds __remove_pages() to remove_memory(). Then the range of
phys_start_pfn argument and nr_pages argument in __remove_pagse() may
have different zone. So zone argument is removed from __remove_pages()
and __remove_pages() caluculates zone in each section.

When CONFIG_SPARSEMEM_VMEMMAP is defined, there is no way to remove a memmap.
So __remove_section only calls unregister_memory_section().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |    5 +----
 include/linux/memory_hotplug.h                  |    3 +--
 mm/memory_hotplug.c                             |   20 +++++++++++++-------
 3 files changed, 15 insertions(+), 13 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:05.919169458 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:10.170116406 +0900
@@ -275,11 +275,14 @@ static int __meminit __add_section(int n
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
-	/*
-	 * XXX: Freeing memmap with vmemmap is not implement yet.
-	 *      This should be removed later.
-	 */
-	return -EBUSY;
+	int ret;
+
+	if (!valid_section(ms))
+		return ret;
+
+	ret = unregister_memory_section(ms);
+
+	return ret;
 }
 #else
 static int __remove_section(struct zone *zone, struct mem_section *ms)
@@ -346,11 +349,11 @@ EXPORT_SYMBOL_GPL(__add_pages);
  * sure that pages are marked reserved and zones are adjust properly by
  * calling offline_pages().
  */
-int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
-		 unsigned long nr_pages)
+int __remove_pages(unsigned long phys_start_pfn, unsigned long nr_pages)
 {
 	unsigned long i, ret = 0;
 	int sections_to_remove;
+	struct zone *zone;

 	/*
 	 * We can only remove entire sections
@@ -363,6 +366,7 @@ int __remove_pages(struct zone *zone, un
 	sections_to_remove = nr_pages / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
+		zone = page_zone(pfn_to_page(pfn));
 		ret = __remove_section(zone, __pfn_to_section(pfn));
 		if (ret)
 			break;
@@ -664,6 +668,8 @@ int remove_memory(int nid, u64 start, u6
 	lock_memory_hotplug();
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size - 1, "System RAM");
+
+	__remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 	unlock_memory_hotplug();
 	return 0;

Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:10.170116406 +0900
@@ -89,8 +89,7 @@ extern bool is_pageblock_removable_noloc
 /* reasonably generic interface to expand the physical pages in a zone  */
 extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn,
 	unsigned long nr_pages);
-extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
-	unsigned long nr_pages);
+extern int __remove_pages(unsigned long start_pfn, unsigned long nr_pages);

 #ifdef CONFIG_NUMA
 extern int memory_add_physaddr_to_nid(u64 start);
Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c
===================================================================
--- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:05.920169437
+0900
+++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:10.172116353 +0900
@@ -76,7 +76,6 @@ unsigned long memory_block_size_bytes(vo
 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
 {
 	unsigned long start, start_pfn;
-	struct zone *zone;
 	int i, ret;
 	int sections_to_remove;

@@ -87,8 +86,6 @@ static int pseries_remove_memblock(unsig
 		return 0;
 	}

-	zone = page_zone(pfn_to_page(start_pfn));
-
 	/*
 	 * Remove section mappings and sysfs entries for the
 	 * section of the memory we are removing.
@@ -101,7 +98,7 @@ static int pseries_remove_memblock(unsig
 	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
-		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
+		ret = __remove_pages(start_pfn,  PAGES_PER_SECTION);
 		if (ret)
 			return ret;
 	}

[RFC PATCH v2 7/13] memory-hotplug : remove_memory calls __remove_pages

[Yasuaki Ishimatsu]

The patch adds __remove_pages() to remove_memory(). Then the range of
phys_start_pfn argument and nr_pages argument in __remove_pagse() may
have different zone. So zone argument is removed from __remove_pages()
and __remove_pages() caluculates zone in each section.

When CONFIG_SPARSEMEM_VMEMMAP is defined, there is no way to remove a memmap.
So __remove_section only calls unregister_memory_section().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |    5 +----
 include/linux/memory_hotplug.h                  |    3 +--
 mm/memory_hotplug.c                             |   20 +++++++++++++-------
 3 files changed, 15 insertions(+), 13 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:05.919169458 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:10.170116406 +0900
@@ -275,11 +275,14 @@ static int __meminit __add_section(int n
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
-	/*
-	 * XXX: Freeing memmap with vmemmap is not implement yet.
-	 *      This should be removed later.
-	 */
-	return -EBUSY;
+	int ret;
+
+	if (!valid_section(ms))
+		return ret;
+
+	ret = unregister_memory_section(ms);
+
+	return ret;
 }
 #else
 static int __remove_section(struct zone *zone, struct mem_section *ms)
@@ -346,11 +349,11 @@ EXPORT_SYMBOL_GPL(__add_pages);
  * sure that pages are marked reserved and zones are adjust properly by
  * calling offline_pages().
  */
-int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
-		 unsigned long nr_pages)
+int __remove_pages(unsigned long phys_start_pfn, unsigned long nr_pages)
 {
 	unsigned long i, ret = 0;
 	int sections_to_remove;
+	struct zone *zone;

 	/*
 	 * We can only remove entire sections
@@ -363,6 +366,7 @@ int __remove_pages(struct zone *zone, un
 	sections_to_remove = nr_pages / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
+		zone = page_zone(pfn_to_page(pfn));
 		ret = __remove_section(zone, __pfn_to_section(pfn));
 		if (ret)
 			break;
@@ -664,6 +668,8 @@ int remove_memory(int nid, u64 start, u6
 	lock_memory_hotplug();
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size - 1, "System RAM");
+
+	__remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 	unlock_memory_hotplug();
 	return 0;

Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:10.170116406 +0900
@@ -89,8 +89,7 @@ extern bool is_pageblock_removable_noloc
 /* reasonably generic interface to expand the physical pages in a zone  */
 extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn,
 	unsigned long nr_pages);
-extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
-	unsigned long nr_pages);
+extern int __remove_pages(unsigned long start_pfn, unsigned long nr_pages);

 #ifdef CONFIG_NUMA
 extern int memory_add_physaddr_to_nid(u64 start);
Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c
===================================================================
--- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:05.920169437
+0900
+++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:10.172116353 +0900
@@ -76,7 +76,6 @@ unsigned long memory_block_size_bytes(vo
 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
 {
 	unsigned long start, start_pfn;
-	struct zone *zone;
 	int i, ret;
 	int sections_to_remove;

@@ -87,8 +86,6 @@ static int pseries_remove_memblock(unsig
 		return 0;
 	}

-	zone = page_zone(pfn_to_page(start_pfn));
-
 	/*
 	 * Remove section mappings and sysfs entries for the
 	 * section of the memory we are removing.
@@ -101,7 +98,7 @@ static int pseries_remove_memblock(unsig
 	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
-		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
+		ret = __remove_pages(start_pfn,  PAGES_PER_SECTION);
 		if (ret)
 			return ret;
 	}

[RFC PATCH v2 7/13] memory-hotplug : remove_memory calls __remove_pages

[Yasuaki Ishimatsu]

The patch adds __remove_pages() to remove_memory(). Then the range of
phys_start_pfn argument and nr_pages argument in __remove_pagse() may
have different zone. So zone argument is removed from __remove_pages()
and __remove_pages() caluculates zone in each section.

When CONFIG_SPARSEMEM_VMEMMAP is defined, there is no way to remove a memmap.
So __remove_section only calls unregister_memory_section().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |    5 +----
 include/linux/memory_hotplug.h                  |    3 +--
 mm/memory_hotplug.c                             |   20 +++++++++++++-------
 3 files changed, 15 insertions(+), 13 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:05.919169458 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:10.170116406 +0900
@@ -275,11 +275,14 @@ static int __meminit __add_section(int n
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
-	/*
-	 * XXX: Freeing memmap with vmemmap is not implement yet.
-	 *      This should be removed later.
-	 */
-	return -EBUSY;
+	int ret;
+
+	if (!valid_section(ms))
+		return ret;
+
+	ret = unregister_memory_section(ms);
+
+	return ret;
 }
 #else
 static int __remove_section(struct zone *zone, struct mem_section *ms)
@@ -346,11 +349,11 @@ EXPORT_SYMBOL_GPL(__add_pages);
  * sure that pages are marked reserved and zones are adjust properly by
  * calling offline_pages().
  */
-int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
-		 unsigned long nr_pages)
+int __remove_pages(unsigned long phys_start_pfn, unsigned long nr_pages)
 {
 	unsigned long i, ret = 0;
 	int sections_to_remove;
+	struct zone *zone;

 	/*
 	 * We can only remove entire sections
@@ -363,6 +366,7 @@ int __remove_pages(struct zone *zone, un
 	sections_to_remove = nr_pages / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
+		zone = page_zone(pfn_to_page(pfn));
 		ret = __remove_section(zone, __pfn_to_section(pfn));
 		if (ret)
 			break;
@@ -664,6 +668,8 @@ int remove_memory(int nid, u64 start, u6
 	lock_memory_hotplug();
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size - 1, "System RAM");
+
+	__remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 	unlock_memory_hotplug();
 	return 0;

Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:10.170116406 +0900
@@ -89,8 +89,7 @@ extern bool is_pageblock_removable_noloc
 /* reasonably generic interface to expand the physical pages in a zone  */
 extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn,
 	unsigned long nr_pages);
-extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
-	unsigned long nr_pages);
+extern int __remove_pages(unsigned long start_pfn, unsigned long nr_pages);

 #ifdef CONFIG_NUMA
 extern int memory_add_physaddr_to_nid(u64 start);
Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c
===================================================================
--- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:05.920169437
+0900
+++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:10.172116353 +0900
@@ -76,7 +76,6 @@ unsigned long memory_block_size_bytes(vo
 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
 {
 	unsigned long start, start_pfn;
-	struct zone *zone;
 	int i, ret;
 	int sections_to_remove;

@@ -87,8 +86,6 @@ static int pseries_remove_memblock(unsig
 		return 0;
 	}

-	zone = page_zone(pfn_to_page(start_pfn));
-
 	/*
 	 * Remove section mappings and sysfs entries for the
 	 * section of the memory we are removing.
@@ -101,7 +98,7 @@ static int pseries_remove_memblock(unsig
 	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
-		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
+		ret = __remove_pages(start_pfn,  PAGES_PER_SECTION);
 		if (ret)
 			return ret;
 	}

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 7/13] memory-hotplug : remove_memory calls __remove_pages

[Yasuaki Ishimatsu]

The patch adds __remove_pages() to remove_memory(). Then the range of
phys_start_pfn argument and nr_pages argument in __remove_pagse() may
have different zone. So zone argument is removed from __remove_pages()
and __remove_pages() caluculates zone in each section.

When CONFIG_SPARSEMEM_VMEMMAP is defined, there is no way to remove a memmap.
So __remove_section only calls unregister_memory_section().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/powerpc/platforms/pseries/hotplug-memory.c |    5 +----
 include/linux/memory_hotplug.h                  |    3 +--
 mm/memory_hotplug.c                             |   20 +++++++++++++-------
 3 files changed, 15 insertions(+), 13 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:05.919169458 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:10.170116406 +0900
@@ -275,11 +275,14 @@ static int __meminit __add_section(int n
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
-	/*
-	 * XXX: Freeing memmap with vmemmap is not implement yet.
-	 *      This should be removed later.
-	 */
-	return -EBUSY;
+	int ret;
+
+	if (!valid_section(ms))
+		return ret;
+
+	ret = unregister_memory_section(ms);
+
+	return ret;
 }
 #else
 static int __remove_section(struct zone *zone, struct mem_section *ms)
@@ -346,11 +349,11 @@ EXPORT_SYMBOL_GPL(__add_pages);
  * sure that pages are marked reserved and zones are adjust properly by
  * calling offline_pages().
  */
-int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
-		 unsigned long nr_pages)
+int __remove_pages(unsigned long phys_start_pfn, unsigned long nr_pages)
 {
 	unsigned long i, ret = 0;
 	int sections_to_remove;
+	struct zone *zone;

 	/*
 	 * We can only remove entire sections
@@ -363,6 +366,7 @@ int __remove_pages(struct zone *zone, un
 	sections_to_remove = nr_pages / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
+		zone = page_zone(pfn_to_page(pfn));
 		ret = __remove_section(zone, __pfn_to_section(pfn));
 		if (ret)
 			break;
@@ -664,6 +668,8 @@ int remove_memory(int nid, u64 start, u6
 	lock_memory_hotplug();
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size - 1, "System RAM");
+
+	__remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 	unlock_memory_hotplug();
 	return 0;

Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:10.170116406 +0900
@@ -89,8 +89,7 @@ extern bool is_pageblock_removable_noloc
 /* reasonably generic interface to expand the physical pages in a zone  */
 extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn,
 	unsigned long nr_pages);
-extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
-	unsigned long nr_pages);
+extern int __remove_pages(unsigned long start_pfn, unsigned long nr_pages);

 #ifdef CONFIG_NUMA
 extern int memory_add_physaddr_to_nid(u64 start);
Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c
===================================================================
--- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:05.920169437
+0900
+++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c	2012-07-03 14:22:10.172116353 +0900
@@ -76,7 +76,6 @@ unsigned long memory_block_size_bytes(vo
 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
 {
 	unsigned long start, start_pfn;
-	struct zone *zone;
 	int i, ret;
 	int sections_to_remove;

@@ -87,8 +86,6 @@ static int pseries_remove_memblock(unsig
 		return 0;
 	}

-	zone = page_zone(pfn_to_page(start_pfn));
-
 	/*
 	 * Remove section mappings and sysfs entries for the
 	 * section of the memory we are removing.
@@ -101,7 +98,7 @@ static int pseries_remove_memblock(unsig
 	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
-		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
+		ret = __remove_pages(start_pfn,  PAGES_PER_SECTION);
 		if (ret)
 			return ret;
 	}

[RFC PATCH v2 8/13] memory-hotplug : check page type in get_page_bootmem

[Yasuaki Ishimatsu]

There is a possibility that get_page_bootmem() is called to the same page many
times. So when get_page_bootmem is called to the same page, the function only
increments page->_count.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:10.170116406 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:12.299089413 +0900
@@ -95,10 +95,17 @@ static void release_memory_resource(stru
 static void get_page_bootmem(unsigned long info,  struct page *page,
 			     unsigned long type)
 {
-	page->lru.next = (struct list_head *) type;
-	SetPagePrivate(page);
-	set_page_private(page, info);
-	atomic_inc(&page->_count);
+	unsigned long page_type;
+
+	page_type = (unsigned long) page->lru.next;
+	if (type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
+	    type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE){
+		page->lru.next = (struct list_head *) type;
+		SetPagePrivate(page);
+		set_page_private(page, info);
+		atomic_inc(&page->_count);
+	} else
+		atomic_inc(&page->_count);
 }

 /* reference to __meminit __free_pages_bootmem is valid

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 8/13] memory-hotplug : check page type in get_page_bootmem

[Yasuaki Ishimatsu]

There is a possibility that get_page_bootmem() is called to the same page many
times. So when get_page_bootmem is called to the same page, the function only
increments page->_count.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:10.170116406 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:12.299089413 +0900
@@ -95,10 +95,17 @@ static void release_memory_resource(stru
 static void get_page_bootmem(unsigned long info,  struct page *page,
 			     unsigned long type)
 {
-	page->lru.next = (struct list_head *) type;
-	SetPagePrivate(page);
-	set_page_private(page, info);
-	atomic_inc(&page->_count);
+	unsigned long page_type;
+
+	page_type = (unsigned long) page->lru.next;
+	if (type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
+	    type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE){
+		page->lru.next = (struct list_head *) type;
+		SetPagePrivate(page);
+		set_page_private(page, info);
+		atomic_inc(&page->_count);
+	} else
+		atomic_inc(&page->_count);
 }

 /* reference to __meminit __free_pages_bootmem is valid

[RFC PATCH v2 8/13] memory-hotplug : check page type in get_page_bootmem

[Yasuaki Ishimatsu]

There is a possibility that get_page_bootmem() is called to the same page many
times. So when get_page_bootmem is called to the same page, the function only
increments page->_count.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:10.170116406 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:12.299089413 +0900
@@ -95,10 +95,17 @@ static void release_memory_resource(stru
 static void get_page_bootmem(unsigned long info,  struct page *page,
 			     unsigned long type)
 {
-	page->lru.next = (struct list_head *) type;
-	SetPagePrivate(page);
-	set_page_private(page, info);
-	atomic_inc(&page->_count);
+	unsigned long page_type;
+
+	page_type = (unsigned long) page->lru.next;
+	if (type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
+	    type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE){
+		page->lru.next = (struct list_head *) type;
+		SetPagePrivate(page);
+		set_page_private(page, info);
+		atomic_inc(&page->_count);
+	} else
+		atomic_inc(&page->_count);
 }

 /* reference to __meminit __free_pages_bootmem is valid

[RFC PATCH v2 9/13] memory-hotplug : move register_page_bootmem_info_node and put_page_bootmem for sparse-vmemmap

[Yasuaki Ishimatsu]

For implementing register_page_bootmem_info_node of sparse-vmemmap,
register_page_bootmem_info_node and put_page_bootmem are moved to
memory_hotplug.c

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 include/linux/memory_hotplug.h |    9 ---------
 mm/memory_hotplug.c            |    8 ++++++--
 2 files changed, 6 insertions(+), 11 deletions(-)

Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:22:10.170116406 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:14.409063086 +0900
@@ -160,17 +160,8 @@ static inline void arch_refresh_nodedata
 #endif /* CONFIG_NUMA */
 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */

-#ifdef CONFIG_SPARSEMEM_VMEMMAP
-static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
-{
-}
-static inline void put_page_bootmem(struct page *page)
-{
-}
-#else
 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
 extern void put_page_bootmem(struct page *page);
-#endif

 /*
  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:12.299089413 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:14.419062959 +0900
@@ -91,7 +91,6 @@ static void release_memory_resource(stru
 }

 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
-#ifndef CONFIG_SPARSEMEM_VMEMMAP
 static void get_page_bootmem(unsigned long info,  struct page *page,
 			     unsigned long type)
 {
@@ -127,6 +126,7 @@ void __ref put_page_bootmem(struct page

 }

+#ifndef CONFIG_SPARSEMEM_VMEMMAP
 static void register_page_bootmem_info_section(unsigned long start_pfn)
 {
 	unsigned long *usemap, mapsize, section_nr, i;
@@ -163,6 +163,11 @@ static void register_page_bootmem_info_s
 		get_page_bootmem(section_nr, page, MIX_SECTION_INFO);

 }
+#else
+static inline void register_page_bootmem_info_section(unsigned long start_pfn)
+{
+}
+#endif

 void register_page_bootmem_info_node(struct pglist_data *pgdat)
 {
@@ -198,7 +203,6 @@ void register_page_bootmem_info_node(str
 		register_page_bootmem_info_section(pfn);

 }
-#endif /* !CONFIG_SPARSEMEM_VMEMMAP */

 static void grow_zone_span(struct zone *zone, unsigned long start_pfn,
 			   unsigned long end_pfn)

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 9/13] memory-hotplug : move register_page_bootmem_info_node and put_page_bootmem for sparse-vmemmap

[Yasuaki Ishimatsu]

For implementing register_page_bootmem_info_node of sparse-vmemmap,
register_page_bootmem_info_node and put_page_bootmem are moved to
memory_hotplug.c

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 include/linux/memory_hotplug.h |    9 ---------
 mm/memory_hotplug.c            |    8 ++++++--
 2 files changed, 6 insertions(+), 11 deletions(-)

Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:22:10.170116406 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:14.409063086 +0900
@@ -160,17 +160,8 @@ static inline void arch_refresh_nodedata
 #endif /* CONFIG_NUMA */
 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */

-#ifdef CONFIG_SPARSEMEM_VMEMMAP
-static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
-{
-}
-static inline void put_page_bootmem(struct page *page)
-{
-}
-#else
 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
 extern void put_page_bootmem(struct page *page);
-#endif

 /*
  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:12.299089413 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:14.419062959 +0900
@@ -91,7 +91,6 @@ static void release_memory_resource(stru
 }

 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
-#ifndef CONFIG_SPARSEMEM_VMEMMAP
 static void get_page_bootmem(unsigned long info,  struct page *page,
 			     unsigned long type)
 {
@@ -127,6 +126,7 @@ void __ref put_page_bootmem(struct page

 }

+#ifndef CONFIG_SPARSEMEM_VMEMMAP
 static void register_page_bootmem_info_section(unsigned long start_pfn)
 {
 	unsigned long *usemap, mapsize, section_nr, i;
@@ -163,6 +163,11 @@ static void register_page_bootmem_info_s
 		get_page_bootmem(section_nr, page, MIX_SECTION_INFO);

 }
+#else
+static inline void register_page_bootmem_info_section(unsigned long start_pfn)
+{
+}
+#endif

 void register_page_bootmem_info_node(struct pglist_data *pgdat)
 {
@@ -198,7 +203,6 @@ void register_page_bootmem_info_node(str
 		register_page_bootmem_info_section(pfn);

 }
-#endif /* !CONFIG_SPARSEMEM_VMEMMAP */

 static void grow_zone_span(struct zone *zone, unsigned long start_pfn,
 			   unsigned long end_pfn)

[RFC PATCH v2 9/13] memory-hotplug : move register_page_bootmem_info_node and put_page_bootmem for sparse-vmemmap

[Yasuaki Ishimatsu]

For implementing register_page_bootmem_info_node of sparse-vmemmap,
register_page_bootmem_info_node and put_page_bootmem are moved to
memory_hotplug.c

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 include/linux/memory_hotplug.h |    9 ---------
 mm/memory_hotplug.c            |    8 ++++++--
 2 files changed, 6 insertions(+), 11 deletions(-)

Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:22:10.170116406 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:14.409063086 +0900
@@ -160,17 +160,8 @@ static inline void arch_refresh_nodedata
 #endif /* CONFIG_NUMA */
 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */

-#ifdef CONFIG_SPARSEMEM_VMEMMAP
-static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
-{
-}
-static inline void put_page_bootmem(struct page *page)
-{
-}
-#else
 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
 extern void put_page_bootmem(struct page *page);
-#endif

 /*
  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:12.299089413 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:14.419062959 +0900
@@ -91,7 +91,6 @@ static void release_memory_resource(stru
 }

 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
-#ifndef CONFIG_SPARSEMEM_VMEMMAP
 static void get_page_bootmem(unsigned long info,  struct page *page,
 			     unsigned long type)
 {
@@ -127,6 +126,7 @@ void __ref put_page_bootmem(struct page

 }

+#ifndef CONFIG_SPARSEMEM_VMEMMAP
 static void register_page_bootmem_info_section(unsigned long start_pfn)
 {
 	unsigned long *usemap, mapsize, section_nr, i;
@@ -163,6 +163,11 @@ static void register_page_bootmem_info_s
 		get_page_bootmem(section_nr, page, MIX_SECTION_INFO);

 }
+#else
+static inline void register_page_bootmem_info_section(unsigned long start_pfn)
+{
+}
+#endif

 void register_page_bootmem_info_node(struct pglist_data *pgdat)
 {
@@ -198,7 +203,6 @@ void register_page_bootmem_info_node(str
 		register_page_bootmem_info_section(pfn);

 }
-#endif /* !CONFIG_SPARSEMEM_VMEMMAP */

 static void grow_zone_span(struct zone *zone, unsigned long start_pfn,
 			   unsigned long end_pfn)

[RFC PATCH v2 10/13] memory-hotplug : implement register_page_bootmem_info_section of sparse-vmemmap

[Yasuaki Ishimatsu]

For removing memmap region of sparse-vmemmap which is allocated bootmem,
memmap region of sparse-vmemmap needs to be registered by get_page_bootmem().
So the patch searches pages of virtual mapping and registers the pages by
get_page_bootmem().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/x86/mm/init_64.c          |   53 +++++++++++++++++++++++++++++++++++++++++
 include/linux/memory_hotplug.h |    2 +
 include/linux/mm.h             |    3 +-
 mm/memory_hotplug.c            |   23 +++++++++++++++--
 4 files changed, 77 insertions(+), 4 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:14.419062959 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:18.522011667 +0900
@@ -91,8 +91,8 @@ static void release_memory_resource(stru
 }

 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
-static void get_page_bootmem(unsigned long info,  struct page *page,
-			     unsigned long type)
+void get_page_bootmem(unsigned long info,  struct page *page,
+		      unsigned long type)
 {
 	unsigned long page_type;

@@ -164,8 +164,25 @@ static void register_page_bootmem_info_s

 }
 #else
-static inline void register_page_bootmem_info_section(unsigned long start_pfn)
+static void register_page_bootmem_info_section(unsigned long start_pfn)
 {
+	unsigned long mapsize, section_nr;
+	struct mem_section *ms;
+	struct page *page, *memmap;
+
+	if (!pfn_valid(start_pfn))
+		return;
+
+	section_nr = pfn_to_section_nr(start_pfn);
+	ms = __nr_to_section(section_nr);
+
+	memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
+
+	page = virt_to_page(memmap);
+	mapsize = sizeof(struct page) * PAGES_PER_SECTION;
+	mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
+
+	register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
 }
 #endif

Index: linux-3.5-rc4/include/linux/mm.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/mm.h	2012-07-03 14:21:45.223427904 +0900
+++ linux-3.5-rc4/include/linux/mm.h	2012-07-03 14:22:18.530011567 +0900
@@ -1586,7 +1586,8 @@ int vmemmap_populate_basepages(struct pa
 						unsigned long pages, int node);
 int vmemmap_populate(struct page *start_page, unsigned long pages, int node);
 void vmemmap_populate_print_last(void);
-
+void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
+				  unsigned long size);

 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc4/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc4.orig/arch/x86/mm/init_64.c	2012-07-03 14:21:45.228427843 +0900
+++ linux-3.5-rc4/arch/x86/mm/init_64.c	2012-07-03 14:22:18.538011465 +0900
@@ -978,6 +978,59 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }

+void __meminit
+register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page,
+			     unsigned long size)
+{
+	unsigned long addr = (unsigned long)start_page;
+	unsigned long end = (unsigned long)(start_page + size);
+	unsigned long next;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	for (; addr < end; addr = next) {
+		pte_t *pte = NULL;
+
+		pgd = pgd_offset_k(addr);
+		if (pgd_none(*pgd)) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			continue;
+		}
+		get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
+
+		pud = pud_offset(pgd, addr);
+		if (pud_none(*pud)) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			continue;
+		}
+		get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
+
+		if (!cpu_has_pse) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			pmd = pmd_offset(pud, addr);
+			if (pmd_none(*pmd))
+				continue;
+			get_page_bootmem(section_nr, pmd_page(*pmd),
+					 MIX_SECTION_INFO);
+
+			pte = pte_offset_kernel(pmd, addr);
+			if (pte_none(*pte))
+				continue;
+			get_page_bootmem(section_nr, pte_page(*pte),
+					 SECTION_INFO);
+		} else {
+			next = pmd_addr_end(addr, end);
+
+			pmd = pmd_offset(pud, addr);
+			if (pmd_none(*pmd))
+				continue;
+			get_page_bootmem(section_nr, pmd_page(*pmd),
+					 SECTION_INFO);
+		}
+	}
+}
+
 void __meminit vmemmap_populate_print_last(void)
 {
 	if (p_start) {
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:22:14.409063086 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:18.541011428 +0900
@@ -162,6 +162,8 @@ static inline void arch_refresh_nodedata

 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
 extern void put_page_bootmem(struct page *page);
+extern void get_page_bootmem(unsigned long ingo, struct page *page,
+			     unsigned long type);

 /*
  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug

[RFC PATCH v2 10/13] memory-hotplug : implement register_page_bootmem_info_section of sparse-vmemmap

[Yasuaki Ishimatsu]

For removing memmap region of sparse-vmemmap which is allocated bootmem,
memmap region of sparse-vmemmap needs to be registered by get_page_bootmem().
So the patch searches pages of virtual mapping and registers the pages by
get_page_bootmem().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/x86/mm/init_64.c          |   53 +++++++++++++++++++++++++++++++++++++++++
 include/linux/memory_hotplug.h |    2 +
 include/linux/mm.h             |    3 +-
 mm/memory_hotplug.c            |   23 +++++++++++++++--
 4 files changed, 77 insertions(+), 4 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:14.419062959 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:18.522011667 +0900
@@ -91,8 +91,8 @@ static void release_memory_resource(stru
 }

 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
-static void get_page_bootmem(unsigned long info,  struct page *page,
-			     unsigned long type)
+void get_page_bootmem(unsigned long info,  struct page *page,
+		      unsigned long type)
 {
 	unsigned long page_type;

@@ -164,8 +164,25 @@ static void register_page_bootmem_info_s

 }
 #else
-static inline void register_page_bootmem_info_section(unsigned long start_pfn)
+static void register_page_bootmem_info_section(unsigned long start_pfn)
 {
+	unsigned long mapsize, section_nr;
+	struct mem_section *ms;
+	struct page *page, *memmap;
+
+	if (!pfn_valid(start_pfn))
+		return;
+
+	section_nr = pfn_to_section_nr(start_pfn);
+	ms = __nr_to_section(section_nr);
+
+	memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
+
+	page = virt_to_page(memmap);
+	mapsize = sizeof(struct page) * PAGES_PER_SECTION;
+	mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
+
+	register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
 }
 #endif

Index: linux-3.5-rc4/include/linux/mm.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/mm.h	2012-07-03 14:21:45.223427904 +0900
+++ linux-3.5-rc4/include/linux/mm.h	2012-07-03 14:22:18.530011567 +0900
@@ -1586,7 +1586,8 @@ int vmemmap_populate_basepages(struct pa
 						unsigned long pages, int node);
 int vmemmap_populate(struct page *start_page, unsigned long pages, int node);
 void vmemmap_populate_print_last(void);
-
+void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
+				  unsigned long size);

 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc4/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc4.orig/arch/x86/mm/init_64.c	2012-07-03 14:21:45.228427843 +0900
+++ linux-3.5-rc4/arch/x86/mm/init_64.c	2012-07-03 14:22:18.538011465 +0900
@@ -978,6 +978,59 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }

+void __meminit
+register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page,
+			     unsigned long size)
+{
+	unsigned long addr = (unsigned long)start_page;
+	unsigned long end = (unsigned long)(start_page + size);
+	unsigned long next;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	for (; addr < end; addr = next) {
+		pte_t *pte = NULL;
+
+		pgd = pgd_offset_k(addr);
+		if (pgd_none(*pgd)) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			continue;
+		}
+		get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
+
+		pud = pud_offset(pgd, addr);
+		if (pud_none(*pud)) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			continue;
+		}
+		get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
+
+		if (!cpu_has_pse) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			pmd = pmd_offset(pud, addr);
+			if (pmd_none(*pmd))
+				continue;
+			get_page_bootmem(section_nr, pmd_page(*pmd),
+					 MIX_SECTION_INFO);
+
+			pte = pte_offset_kernel(pmd, addr);
+			if (pte_none(*pte))
+				continue;
+			get_page_bootmem(section_nr, pte_page(*pte),
+					 SECTION_INFO);
+		} else {
+			next = pmd_addr_end(addr, end);
+
+			pmd = pmd_offset(pud, addr);
+			if (pmd_none(*pmd))
+				continue;
+			get_page_bootmem(section_nr, pmd_page(*pmd),
+					 SECTION_INFO);
+		}
+	}
+}
+
 void __meminit vmemmap_populate_print_last(void)
 {
 	if (p_start) {
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:22:14.409063086 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:18.541011428 +0900
@@ -162,6 +162,8 @@ static inline void arch_refresh_nodedata

 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
 extern void put_page_bootmem(struct page *page);
+extern void get_page_bootmem(unsigned long ingo, struct page *page,
+			     unsigned long type);

 /*
  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug

[RFC PATCH v2 10/13] memory-hotplug : implement register_page_bootmem_info_section of sparse-vmemmap

[Yasuaki Ishimatsu]

For removing memmap region of sparse-vmemmap which is allocated bootmem,
memmap region of sparse-vmemmap needs to be registered by get_page_bootmem().
So the patch searches pages of virtual mapping and registers the pages by
get_page_bootmem().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/x86/mm/init_64.c          |   53 +++++++++++++++++++++++++++++++++++++++++
 include/linux/memory_hotplug.h |    2 +
 include/linux/mm.h             |    3 +-
 mm/memory_hotplug.c            |   23 +++++++++++++++--
 4 files changed, 77 insertions(+), 4 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:14.419062959 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:18.522011667 +0900
@@ -91,8 +91,8 @@ static void release_memory_resource(stru
 }

 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
-static void get_page_bootmem(unsigned long info,  struct page *page,
-			     unsigned long type)
+void get_page_bootmem(unsigned long info,  struct page *page,
+		      unsigned long type)
 {
 	unsigned long page_type;

@@ -164,8 +164,25 @@ static void register_page_bootmem_info_s

 }
 #else
-static inline void register_page_bootmem_info_section(unsigned long start_pfn)
+static void register_page_bootmem_info_section(unsigned long start_pfn)
 {
+	unsigned long mapsize, section_nr;
+	struct mem_section *ms;
+	struct page *page, *memmap;
+
+	if (!pfn_valid(start_pfn))
+		return;
+
+	section_nr = pfn_to_section_nr(start_pfn);
+	ms = __nr_to_section(section_nr);
+
+	memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
+
+	page = virt_to_page(memmap);
+	mapsize = sizeof(struct page) * PAGES_PER_SECTION;
+	mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
+
+	register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
 }
 #endif

Index: linux-3.5-rc4/include/linux/mm.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/mm.h	2012-07-03 14:21:45.223427904 +0900
+++ linux-3.5-rc4/include/linux/mm.h	2012-07-03 14:22:18.530011567 +0900
@@ -1586,7 +1586,8 @@ int vmemmap_populate_basepages(struct pa
 						unsigned long pages, int node);
 int vmemmap_populate(struct page *start_page, unsigned long pages, int node);
 void vmemmap_populate_print_last(void);
-
+void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
+				  unsigned long size);

 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc4/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc4.orig/arch/x86/mm/init_64.c	2012-07-03 14:21:45.228427843 +0900
+++ linux-3.5-rc4/arch/x86/mm/init_64.c	2012-07-03 14:22:18.538011465 +0900
@@ -978,6 +978,59 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }

+void __meminit
+register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page,
+			     unsigned long size)
+{
+	unsigned long addr = (unsigned long)start_page;
+	unsigned long end = (unsigned long)(start_page + size);
+	unsigned long next;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	for (; addr < end; addr = next) {
+		pte_t *pte = NULL;
+
+		pgd = pgd_offset_k(addr);
+		if (pgd_none(*pgd)) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			continue;
+		}
+		get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
+
+		pud = pud_offset(pgd, addr);
+		if (pud_none(*pud)) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			continue;
+		}
+		get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
+
+		if (!cpu_has_pse) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			pmd = pmd_offset(pud, addr);
+			if (pmd_none(*pmd))
+				continue;
+			get_page_bootmem(section_nr, pmd_page(*pmd),
+					 MIX_SECTION_INFO);
+
+			pte = pte_offset_kernel(pmd, addr);
+			if (pte_none(*pte))
+				continue;
+			get_page_bootmem(section_nr, pte_page(*pte),
+					 SECTION_INFO);
+		} else {
+			next = pmd_addr_end(addr, end);
+
+			pmd = pmd_offset(pud, addr);
+			if (pmd_none(*pmd))
+				continue;
+			get_page_bootmem(section_nr, pmd_page(*pmd),
+					 SECTION_INFO);
+		}
+	}
+}
+
 void __meminit vmemmap_populate_print_last(void)
 {
 	if (p_start) {
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:22:14.409063086 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:18.541011428 +0900
@@ -162,6 +162,8 @@ static inline void arch_refresh_nodedata

 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
 extern void put_page_bootmem(struct page *page);
+extern void get_page_bootmem(unsigned long ingo, struct page *page,
+			     unsigned long type);

 /*
  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 10/13] memory-hotplug : implement register_page_bootmem_info_section of sparse-vmemmap

[Yasuaki Ishimatsu]

For removing memmap region of sparse-vmemmap which is allocated bootmem,
memmap region of sparse-vmemmap needs to be registered by get_page_bootmem().
So the patch searches pages of virtual mapping and registers the pages by
get_page_bootmem().

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/x86/mm/init_64.c          |   53 +++++++++++++++++++++++++++++++++++++++++
 include/linux/memory_hotplug.h |    2 +
 include/linux/mm.h             |    3 +-
 mm/memory_hotplug.c            |   23 +++++++++++++++--
 4 files changed, 77 insertions(+), 4 deletions(-)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:14.419062959 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:18.522011667 +0900
@@ -91,8 +91,8 @@ static void release_memory_resource(stru
 }

 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
-static void get_page_bootmem(unsigned long info,  struct page *page,
-			     unsigned long type)
+void get_page_bootmem(unsigned long info,  struct page *page,
+		      unsigned long type)
 {
 	unsigned long page_type;

@@ -164,8 +164,25 @@ static void register_page_bootmem_info_s

 }
 #else
-static inline void register_page_bootmem_info_section(unsigned long start_pfn)
+static void register_page_bootmem_info_section(unsigned long start_pfn)
 {
+	unsigned long mapsize, section_nr;
+	struct mem_section *ms;
+	struct page *page, *memmap;
+
+	if (!pfn_valid(start_pfn))
+		return;
+
+	section_nr = pfn_to_section_nr(start_pfn);
+	ms = __nr_to_section(section_nr);
+
+	memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
+
+	page = virt_to_page(memmap);
+	mapsize = sizeof(struct page) * PAGES_PER_SECTION;
+	mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
+
+	register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
 }
 #endif

Index: linux-3.5-rc4/include/linux/mm.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/mm.h	2012-07-03 14:21:45.223427904 +0900
+++ linux-3.5-rc4/include/linux/mm.h	2012-07-03 14:22:18.530011567 +0900
@@ -1586,7 +1586,8 @@ int vmemmap_populate_basepages(struct pa
 						unsigned long pages, int node);
 int vmemmap_populate(struct page *start_page, unsigned long pages, int node);
 void vmemmap_populate_print_last(void);
-
+void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
+				  unsigned long size);

 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc4/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc4.orig/arch/x86/mm/init_64.c	2012-07-03 14:21:45.228427843 +0900
+++ linux-3.5-rc4/arch/x86/mm/init_64.c	2012-07-03 14:22:18.538011465 +0900
@@ -978,6 +978,59 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }

+void __meminit
+register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page,
+			     unsigned long size)
+{
+	unsigned long addr = (unsigned long)start_page;
+	unsigned long end = (unsigned long)(start_page + size);
+	unsigned long next;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	for (; addr < end; addr = next) {
+		pte_t *pte = NULL;
+
+		pgd = pgd_offset_k(addr);
+		if (pgd_none(*pgd)) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			continue;
+		}
+		get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
+
+		pud = pud_offset(pgd, addr);
+		if (pud_none(*pud)) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			continue;
+		}
+		get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
+
+		if (!cpu_has_pse) {
+			next = (addr + PAGE_SIZE) & PAGE_MASK;
+			pmd = pmd_offset(pud, addr);
+			if (pmd_none(*pmd))
+				continue;
+			get_page_bootmem(section_nr, pmd_page(*pmd),
+					 MIX_SECTION_INFO);
+
+			pte = pte_offset_kernel(pmd, addr);
+			if (pte_none(*pte))
+				continue;
+			get_page_bootmem(section_nr, pte_page(*pte),
+					 SECTION_INFO);
+		} else {
+			next = pmd_addr_end(addr, end);
+
+			pmd = pmd_offset(pud, addr);
+			if (pmd_none(*pmd))
+				continue;
+			get_page_bootmem(section_nr, pmd_page(*pmd),
+					 SECTION_INFO);
+		}
+	}
+}
+
 void __meminit vmemmap_populate_print_last(void)
 {
 	if (p_start) {
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:22:14.409063086 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:22:18.541011428 +0900
@@ -162,6 +162,8 @@ static inline void arch_refresh_nodedata

 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
 extern void put_page_bootmem(struct page *page);
+extern void get_page_bootmem(unsigned long ingo, struct page *page,
+			     unsigned long type);

 /*
  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug

[RFC PATCH v2 11/13] memory-hotplug : free memmap of sparse-vmemmap

[Yasuaki Ishimatsu]

I don't think that all pages of virtual mapping in removed memory can be
freed, since page which type is MIX_SECTION_INFO is difficult to free.
So, the patch only frees page which type is SECTION_INFO at first.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/x86/mm/init_64.c |   91 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/mm.h    |    2 +
 mm/memory_hotplug.c   |    5 ++
 mm/sparse.c           |    5 +-
 4 files changed, 101 insertions(+), 2 deletions(-)

Index: linux-3.5-rc4/include/linux/mm.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/mm.h	2012-07-03 14:22:18.530011567 +0900
+++ linux-3.5-rc4/include/linux/mm.h	2012-07-03 14:22:20.999983872 +0900
@@ -1588,6 +1588,8 @@ int vmemmap_populate(struct page *start_
 void vmemmap_populate_print_last(void);
 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
 				  unsigned long size);
+void vmemmap_kfree(struct page *memmpa, unsigned long nr_pages);
+void vmemmap_free_bootmem(struct page *memmpa, unsigned long nr_pages);

 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc4/mm/sparse.c
===================================================================
--- linux-3.5-rc4.orig/mm/sparse.c	2012-07-03 14:21:45.071429805 +0900
+++ linux-3.5-rc4/mm/sparse.c	2012-07-03 14:22:21.000983767 +0900
@@ -614,12 +614,13 @@ static inline struct page *kmalloc_secti
 	/* This will make the necessary allocations eventually. */
 	return sparse_mem_map_populate(pnum, nid);
 }
-static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
+static void __kfree_section_memmap(struct page *page, unsigned long nr_pages)
 {
-	return; /* XXX: Not implemented yet */
+	vmemmap_kfree(page, nr_pages);
 }
 static void free_map_bootmem(struct page *page, unsigned long nr_pages)
 {
+	vmemmap_free_bootmem(page, nr_pages);
 }
 #else
 static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
Index: linux-3.5-rc4/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc4.orig/arch/x86/mm/init_64.c	2012-07-03 14:22:18.538011465 +0900
+++ linux-3.5-rc4/arch/x86/mm/init_64.c	2012-07-03 14:22:21.007983103 +0900
@@ -978,6 +978,97 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }

+unsigned long find_and_clear_pte_page(unsigned long addr, unsigned long end,
+				      struct page **pp)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long next;
+
+	*pp = NULL;
+
+	pgd = pgd_offset_k(addr);
+	if (pgd_none(*pgd))
+		return (addr + PAGE_SIZE) & PAGE_MASK;
+
+	pud = pud_offset(pgd, addr);
+	if (pud_none(*pud))
+		return (addr + PAGE_SIZE) & PAGE_MASK;
+
+	if (!cpu_has_pse) {
+		next = (addr + PAGE_SIZE) & PAGE_MASK;
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		pte = pte_offset_kernel(pmd, addr);
+		if (pte_none(*pte))
+			return next;
+
+		*pp = pte_page(*pte);
+		pte_clear(&init_mm, addr, pte);
+	} else {
+		next = pmd_addr_end(addr, end);
+
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		*pp = pmd_page(*pmd);
+		pmd_clear(pmd);
+	}
+
+	return next;
+}
+
+void __meminit
+vmemmap_kfree(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	unsigned int order;
+	struct page *page;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		next = find_and_clear_pte_page(addr, end, &page);
+		if (!page)
+			continue;
+
+		if (is_vmalloc_addr(page_address(page)))
+			vfree(page_address(page));
+		else {
+			order = next - addr;
+			free_pages((unsigned long)page_address(page),
+				   get_order(order));
+		}
+	}
+}
+
+void __meminit
+vmemmap_free_bootmem(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	struct page *page;
+	unsigned long magic;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		next = find_and_clear_pte_page(addr, end, &page);
+		if (!page)
+			continue;
+
+		magic = (unsigned long) page->lru.next;
+		if (magic == SECTION_INFO)
+			put_page_bootmem(page);
+	}
+}
+
 void __meminit
 register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page,
 			     unsigned long size)
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:18.522011667 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:21.012982694 +0900
@@ -303,6 +303,8 @@ static int __meminit __add_section(int n
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
+	unsigned long flags;
+	struct pglist_data *pgdat = zone->zone_pgdat;
 	int ret;

 	if (!valid_section(ms))
@@ -310,6 +312,9 @@ static int __remove_section(struct zone

 	ret = unregister_memory_section(ms);

+	pgdat_resize_lock(pgdat, &flags);
+	sparse_remove_one_section(zone, ms);
+	pgdat_resize_unlock(pgdat, &flags);
 	return ret;
 }
 #else

[RFC PATCH v2 11/13] memory-hotplug : free memmap of sparse-vmemmap

[Yasuaki Ishimatsu]

I don't think that all pages of virtual mapping in removed memory can be
freed, since page which type is MIX_SECTION_INFO is difficult to free.
So, the patch only frees page which type is SECTION_INFO at first.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/x86/mm/init_64.c |   91 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/mm.h    |    2 +
 mm/memory_hotplug.c   |    5 ++
 mm/sparse.c           |    5 +-
 4 files changed, 101 insertions(+), 2 deletions(-)

Index: linux-3.5-rc4/include/linux/mm.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/mm.h	2012-07-03 14:22:18.530011567 +0900
+++ linux-3.5-rc4/include/linux/mm.h	2012-07-03 14:22:20.999983872 +0900
@@ -1588,6 +1588,8 @@ int vmemmap_populate(struct page *start_
 void vmemmap_populate_print_last(void);
 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
 				  unsigned long size);
+void vmemmap_kfree(struct page *memmpa, unsigned long nr_pages);
+void vmemmap_free_bootmem(struct page *memmpa, unsigned long nr_pages);

 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc4/mm/sparse.c
===================================================================
--- linux-3.5-rc4.orig/mm/sparse.c	2012-07-03 14:21:45.071429805 +0900
+++ linux-3.5-rc4/mm/sparse.c	2012-07-03 14:22:21.000983767 +0900
@@ -614,12 +614,13 @@ static inline struct page *kmalloc_secti
 	/* This will make the necessary allocations eventually. */
 	return sparse_mem_map_populate(pnum, nid);
 }
-static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
+static void __kfree_section_memmap(struct page *page, unsigned long nr_pages)
 {
-	return; /* XXX: Not implemented yet */
+	vmemmap_kfree(page, nr_pages);
 }
 static void free_map_bootmem(struct page *page, unsigned long nr_pages)
 {
+	vmemmap_free_bootmem(page, nr_pages);
 }
 #else
 static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
Index: linux-3.5-rc4/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc4.orig/arch/x86/mm/init_64.c	2012-07-03 14:22:18.538011465 +0900
+++ linux-3.5-rc4/arch/x86/mm/init_64.c	2012-07-03 14:22:21.007983103 +0900
@@ -978,6 +978,97 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }

+unsigned long find_and_clear_pte_page(unsigned long addr, unsigned long end,
+				      struct page **pp)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long next;
+
+	*pp = NULL;
+
+	pgd = pgd_offset_k(addr);
+	if (pgd_none(*pgd))
+		return (addr + PAGE_SIZE) & PAGE_MASK;
+
+	pud = pud_offset(pgd, addr);
+	if (pud_none(*pud))
+		return (addr + PAGE_SIZE) & PAGE_MASK;
+
+	if (!cpu_has_pse) {
+		next = (addr + PAGE_SIZE) & PAGE_MASK;
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		pte = pte_offset_kernel(pmd, addr);
+		if (pte_none(*pte))
+			return next;
+
+		*pp = pte_page(*pte);
+		pte_clear(&init_mm, addr, pte);
+	} else {
+		next = pmd_addr_end(addr, end);
+
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		*pp = pmd_page(*pmd);
+		pmd_clear(pmd);
+	}
+
+	return next;
+}
+
+void __meminit
+vmemmap_kfree(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	unsigned int order;
+	struct page *page;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		next = find_and_clear_pte_page(addr, end, &page);
+		if (!page)
+			continue;
+
+		if (is_vmalloc_addr(page_address(page)))
+			vfree(page_address(page));
+		else {
+			order = next - addr;
+			free_pages((unsigned long)page_address(page),
+				   get_order(order));
+		}
+	}
+}
+
+void __meminit
+vmemmap_free_bootmem(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	struct page *page;
+	unsigned long magic;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		next = find_and_clear_pte_page(addr, end, &page);
+		if (!page)
+			continue;
+
+		magic = (unsigned long) page->lru.next;
+		if (magic == SECTION_INFO)
+			put_page_bootmem(page);
+	}
+}
+
 void __meminit
 register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page,
 			     unsigned long size)
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:18.522011667 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:21.012982694 +0900
@@ -303,6 +303,8 @@ static int __meminit __add_section(int n
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
+	unsigned long flags;
+	struct pglist_data *pgdat = zone->zone_pgdat;
 	int ret;

 	if (!valid_section(ms))
@@ -310,6 +312,9 @@ static int __remove_section(struct zone

 	ret = unregister_memory_section(ms);

+	pgdat_resize_lock(pgdat, &flags);
+	sparse_remove_one_section(zone, ms);
+	pgdat_resize_unlock(pgdat, &flags);
 	return ret;
 }
 #else

[RFC PATCH v2 11/13] memory-hotplug : free memmap of sparse-vmemmap

[Yasuaki Ishimatsu]

I don't think that all pages of virtual mapping in removed memory can be
freed, since page which type is MIX_SECTION_INFO is difficult to free.
So, the patch only frees page which type is SECTION_INFO at first.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/x86/mm/init_64.c |   91 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/mm.h    |    2 +
 mm/memory_hotplug.c   |    5 ++
 mm/sparse.c           |    5 +-
 4 files changed, 101 insertions(+), 2 deletions(-)

Index: linux-3.5-rc4/include/linux/mm.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/mm.h	2012-07-03 14:22:18.530011567 +0900
+++ linux-3.5-rc4/include/linux/mm.h	2012-07-03 14:22:20.999983872 +0900
@@ -1588,6 +1588,8 @@ int vmemmap_populate(struct page *start_
 void vmemmap_populate_print_last(void);
 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
 				  unsigned long size);
+void vmemmap_kfree(struct page *memmpa, unsigned long nr_pages);
+void vmemmap_free_bootmem(struct page *memmpa, unsigned long nr_pages);

 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc4/mm/sparse.c
===================================================================
--- linux-3.5-rc4.orig/mm/sparse.c	2012-07-03 14:21:45.071429805 +0900
+++ linux-3.5-rc4/mm/sparse.c	2012-07-03 14:22:21.000983767 +0900
@@ -614,12 +614,13 @@ static inline struct page *kmalloc_secti
 	/* This will make the necessary allocations eventually. */
 	return sparse_mem_map_populate(pnum, nid);
 }
-static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
+static void __kfree_section_memmap(struct page *page, unsigned long nr_pages)
 {
-	return; /* XXX: Not implemented yet */
+	vmemmap_kfree(page, nr_pages);
 }
 static void free_map_bootmem(struct page *page, unsigned long nr_pages)
 {
+	vmemmap_free_bootmem(page, nr_pages);
 }
 #else
 static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
Index: linux-3.5-rc4/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc4.orig/arch/x86/mm/init_64.c	2012-07-03 14:22:18.538011465 +0900
+++ linux-3.5-rc4/arch/x86/mm/init_64.c	2012-07-03 14:22:21.007983103 +0900
@@ -978,6 +978,97 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }

+unsigned long find_and_clear_pte_page(unsigned long addr, unsigned long end,
+				      struct page **pp)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long next;
+
+	*pp = NULL;
+
+	pgd = pgd_offset_k(addr);
+	if (pgd_none(*pgd))
+		return (addr + PAGE_SIZE) & PAGE_MASK;
+
+	pud = pud_offset(pgd, addr);
+	if (pud_none(*pud))
+		return (addr + PAGE_SIZE) & PAGE_MASK;
+
+	if (!cpu_has_pse) {
+		next = (addr + PAGE_SIZE) & PAGE_MASK;
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		pte = pte_offset_kernel(pmd, addr);
+		if (pte_none(*pte))
+			return next;
+
+		*pp = pte_page(*pte);
+		pte_clear(&init_mm, addr, pte);
+	} else {
+		next = pmd_addr_end(addr, end);
+
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		*pp = pmd_page(*pmd);
+		pmd_clear(pmd);
+	}
+
+	return next;
+}
+
+void __meminit
+vmemmap_kfree(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	unsigned int order;
+	struct page *page;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		next = find_and_clear_pte_page(addr, end, &page);
+		if (!page)
+			continue;
+
+		if (is_vmalloc_addr(page_address(page)))
+			vfree(page_address(page));
+		else {
+			order = next - addr;
+			free_pages((unsigned long)page_address(page),
+				   get_order(order));
+		}
+	}
+}
+
+void __meminit
+vmemmap_free_bootmem(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	struct page *page;
+	unsigned long magic;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		next = find_and_clear_pte_page(addr, end, &page);
+		if (!page)
+			continue;
+
+		magic = (unsigned long) page->lru.next;
+		if (magic == SECTION_INFO)
+			put_page_bootmem(page);
+	}
+}
+
 void __meminit
 register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page,
 			     unsigned long size)
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:18.522011667 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:21.012982694 +0900
@@ -303,6 +303,8 @@ static int __meminit __add_section(int n
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
+	unsigned long flags;
+	struct pglist_data *pgdat = zone->zone_pgdat;
 	int ret;

 	if (!valid_section(ms))
@@ -310,6 +312,9 @@ static int __remove_section(struct zone

 	ret = unregister_memory_section(ms);

+	pgdat_resize_lock(pgdat, &flags);
+	sparse_remove_one_section(zone, ms);
+	pgdat_resize_unlock(pgdat, &flags);
 	return ret;
 }
 #else

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 11/13] memory-hotplug : free memmap of sparse-vmemmap

[Yasuaki Ishimatsu]

I don't think that all pages of virtual mapping in removed memory can be
freed, since page which type is MIX_SECTION_INFO is difficult to free.
So, the patch only frees page which type is SECTION_INFO at first.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 arch/x86/mm/init_64.c |   91 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/mm.h    |    2 +
 mm/memory_hotplug.c   |    5 ++
 mm/sparse.c           |    5 +-
 4 files changed, 101 insertions(+), 2 deletions(-)

Index: linux-3.5-rc4/include/linux/mm.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/mm.h	2012-07-03 14:22:18.530011567 +0900
+++ linux-3.5-rc4/include/linux/mm.h	2012-07-03 14:22:20.999983872 +0900
@@ -1588,6 +1588,8 @@ int vmemmap_populate(struct page *start_
 void vmemmap_populate_print_last(void);
 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
 				  unsigned long size);
+void vmemmap_kfree(struct page *memmpa, unsigned long nr_pages);
+void vmemmap_free_bootmem(struct page *memmpa, unsigned long nr_pages);

 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc4/mm/sparse.c
===================================================================
--- linux-3.5-rc4.orig/mm/sparse.c	2012-07-03 14:21:45.071429805 +0900
+++ linux-3.5-rc4/mm/sparse.c	2012-07-03 14:22:21.000983767 +0900
@@ -614,12 +614,13 @@ static inline struct page *kmalloc_secti
 	/* This will make the necessary allocations eventually. */
 	return sparse_mem_map_populate(pnum, nid);
 }
-static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
+static void __kfree_section_memmap(struct page *page, unsigned long nr_pages)
 {
-	return; /* XXX: Not implemented yet */
+	vmemmap_kfree(page, nr_pages);
 }
 static void free_map_bootmem(struct page *page, unsigned long nr_pages)
 {
+	vmemmap_free_bootmem(page, nr_pages);
 }
 #else
 static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
Index: linux-3.5-rc4/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc4.orig/arch/x86/mm/init_64.c	2012-07-03 14:22:18.538011465 +0900
+++ linux-3.5-rc4/arch/x86/mm/init_64.c	2012-07-03 14:22:21.007983103 +0900
@@ -978,6 +978,97 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }

+unsigned long find_and_clear_pte_page(unsigned long addr, unsigned long end,
+				      struct page **pp)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long next;
+
+	*pp = NULL;
+
+	pgd = pgd_offset_k(addr);
+	if (pgd_none(*pgd))
+		return (addr + PAGE_SIZE) & PAGE_MASK;
+
+	pud = pud_offset(pgd, addr);
+	if (pud_none(*pud))
+		return (addr + PAGE_SIZE) & PAGE_MASK;
+
+	if (!cpu_has_pse) {
+		next = (addr + PAGE_SIZE) & PAGE_MASK;
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		pte = pte_offset_kernel(pmd, addr);
+		if (pte_none(*pte))
+			return next;
+
+		*pp = pte_page(*pte);
+		pte_clear(&init_mm, addr, pte);
+	} else {
+		next = pmd_addr_end(addr, end);
+
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		*pp = pmd_page(*pmd);
+		pmd_clear(pmd);
+	}
+
+	return next;
+}
+
+void __meminit
+vmemmap_kfree(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	unsigned int order;
+	struct page *page;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		next = find_and_clear_pte_page(addr, end, &page);
+		if (!page)
+			continue;
+
+		if (is_vmalloc_addr(page_address(page)))
+			vfree(page_address(page));
+		else {
+			order = next - addr;
+			free_pages((unsigned long)page_address(page),
+				   get_order(order));
+		}
+	}
+}
+
+void __meminit
+vmemmap_free_bootmem(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	struct page *page;
+	unsigned long magic;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		next = find_and_clear_pte_page(addr, end, &page);
+		if (!page)
+			continue;
+
+		magic = (unsigned long) page->lru.next;
+		if (magic == SECTION_INFO)
+			put_page_bootmem(page);
+	}
+}
+
 void __meminit
 register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page,
 			     unsigned long size)
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:18.522011667 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:21.012982694 +0900
@@ -303,6 +303,8 @@ static int __meminit __add_section(int n
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
+	unsigned long flags;
+	struct pglist_data *pgdat = zone->zone_pgdat;
 	int ret;

 	if (!valid_section(ms))
@@ -310,6 +312,9 @@ static int __remove_section(struct zone

 	ret = unregister_memory_section(ms);

+	pgdat_resize_lock(pgdat, &flags);
+	sparse_remove_one_section(zone, ms);
+	pgdat_resize_unlock(pgdat, &flags);
 	return ret;
 }
 #else

[RFC PATCH v2 12/13] memory-hotplug : add node_device_release

[Yasuaki Ishimatsu]

When calling unregister_node(), the function shows following message at
device_release().

Device 'node2' does not have a release() function, it is broken and must be
fixed.

So the patch implements node_device_release()

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/base/node.c |    7 +++++++
 1 file changed, 7 insertions(+)

Index: linux-3.5-rc4/drivers/base/node.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/node.c	2012-07-03 14:21:44.882432167 +0900
+++ linux-3.5-rc4/drivers/base/node.c	2012-07-03 14:22:23.296951921 +0900
@@ -252,6 +252,12 @@ static inline void hugetlb_register_node
 static inline void hugetlb_unregister_node(struct node *node) {}
 #endif

+static void node_device_release(struct device *dev)
+{
+	struct node *node_dev = to_node(dev);
+
+	memset(node_dev, 0, sizeof(struct node));
+}

 /*
  * register_node - Setup a sysfs device for a node.
@@ -265,6 +271,7 @@ int register_node(struct node *node, int

 	node->dev.id = num;
 	node->dev.bus = &node_subsys;
+	node->dev.release = node_device_release;
 	error = device_register(&node->dev);

 	if (!error){

[RFC PATCH v2 12/13] memory-hotplug : add node_device_release

[Yasuaki Ishimatsu]

When calling unregister_node(), the function shows following message at
device_release().

Device 'node2' does not have a release() function, it is broken and must be
fixed.

So the patch implements node_device_release()

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/base/node.c |    7 +++++++
 1 file changed, 7 insertions(+)

Index: linux-3.5-rc4/drivers/base/node.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/node.c	2012-07-03 14:21:44.882432167 +0900
+++ linux-3.5-rc4/drivers/base/node.c	2012-07-03 14:22:23.296951921 +0900
@@ -252,6 +252,12 @@ static inline void hugetlb_register_node
 static inline void hugetlb_unregister_node(struct node *node) {}
 #endif

+static void node_device_release(struct device *dev)
+{
+	struct node *node_dev = to_node(dev);
+
+	memset(node_dev, 0, sizeof(struct node));
+}

 /*
  * register_node - Setup a sysfs device for a node.
@@ -265,6 +271,7 @@ int register_node(struct node *node, int

 	node->dev.id = num;
 	node->dev.bus = &node_subsys;
+	node->dev.release = node_device_release;
 	error = device_register(&node->dev);

 	if (!error){

[RFC PATCH v2 12/13] memory-hotplug : add node_device_release

[Yasuaki Ishimatsu]

When calling unregister_node(), the function shows following message at
device_release().

Device 'node2' does not have a release() function, it is broken and must be
fixed.

So the patch implements node_device_release()

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/base/node.c |    7 +++++++
 1 file changed, 7 insertions(+)

Index: linux-3.5-rc4/drivers/base/node.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/node.c	2012-07-03 14:21:44.882432167 +0900
+++ linux-3.5-rc4/drivers/base/node.c	2012-07-03 14:22:23.296951921 +0900
@@ -252,6 +252,12 @@ static inline void hugetlb_register_node
 static inline void hugetlb_unregister_node(struct node *node) {}
 #endif

+static void node_device_release(struct device *dev)
+{
+	struct node *node_dev = to_node(dev);
+
+	memset(node_dev, 0, sizeof(struct node));
+}

 /*
  * register_node - Setup a sysfs device for a node.
@@ -265,6 +271,7 @@ int register_node(struct node *node, int

 	node->dev.id = num;
 	node->dev.bus = &node_subsys;
+	node->dev.release = node_device_release;
 	error = device_register(&node->dev);

 	if (!error){

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 12/13] memory-hotplug : add node_device_release

[Yasuaki Ishimatsu]

When calling unregister_node(), the function shows following message at
device_release().

Device 'node2' does not have a release() function, it is broken and must be
fixed.

So the patch implements node_device_release()

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/base/node.c |    7 +++++++
 1 file changed, 7 insertions(+)

Index: linux-3.5-rc4/drivers/base/node.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/node.c	2012-07-03 14:21:44.882432167 +0900
+++ linux-3.5-rc4/drivers/base/node.c	2012-07-03 14:22:23.296951921 +0900
@@ -252,6 +252,12 @@ static inline void hugetlb_register_node
 static inline void hugetlb_unregister_node(struct node *node) {}
 #endif

+static void node_device_release(struct device *dev)
+{
+	struct node *node_dev = to_node(dev);
+
+	memset(node_dev, 0, sizeof(struct node));
+}

 /*
  * register_node - Setup a sysfs device for a node.
@@ -265,6 +271,7 @@ int register_node(struct node *node, int

 	node->dev.id = num;
 	node->dev.bus = &node_subsys;
+	node->dev.release = node_device_release;
 	error = device_register(&node->dev);

 	if (!error){

[RFC PATCH v2 13/13] memory-hotplug : remove sysfs file of node

[Yasuaki Ishimatsu]

The patch adds node_set_offline() and unregister_one_node() to remove_memory()
for removing sysfs file of node.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |    5 +++++
 1 file changed, 5 insertions(+)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:21.012982694 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:25.405925554 +0900
@@ -702,6 +702,11 @@ int remove_memory(int nid, u64 start, u6
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size - 1, "System RAM");

+	if (!node_present_pages(nid)) {
+		node_set_offline(nid);
+		unregister_one_node(nid);
+	}
+
 	__remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 	unlock_memory_hotplug();
 	return 0;

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

[RFC PATCH v2 13/13] memory-hotplug : remove sysfs file of node

[Yasuaki Ishimatsu]

The patch adds node_set_offline() and unregister_one_node() to remove_memory()
for removing sysfs file of node.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |    5 +++++
 1 file changed, 5 insertions(+)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:21.012982694 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:25.405925554 +0900
@@ -702,6 +702,11 @@ int remove_memory(int nid, u64 start, u6
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size - 1, "System RAM");

+	if (!node_present_pages(nid)) {
+		node_set_offline(nid);
+		unregister_one_node(nid);
+	}
+
 	__remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 	unlock_memory_hotplug();
 	return 0;

[RFC PATCH v2 13/13] memory-hotplug : remove sysfs file of node

[Yasuaki Ishimatsu]

The patch adds node_set_offline() and unregister_one_node() to remove_memory()
for removing sysfs file of node.

CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
CC: Len Brown <len.brown@intel.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 mm/memory_hotplug.c |    5 +++++
 1 file changed, 5 insertions(+)

Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:21.012982694 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:25.405925554 +0900
@@ -702,6 +702,11 @@ int remove_memory(int nid, u64 start, u6
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size - 1, "System RAM");

+	if (!node_present_pages(nid)) {
+		node_set_offline(nid);
+		unregister_one_node(nid);
+	}
+
 	__remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 	unlock_memory_hotplug();
 	return 0;

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Wen Congyang]

At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
> acpi_memory_device_remove() has been prepared to remove physical memory.
> But, the function only frees acpi_memory_device currentlry.
> 
> The patch adds following functions into acpi_memory_device_remove():
>   - offline memory
>   - remove physical memory (only return -EBUSY)
>   - free acpi_memory_device
> 
> CC: David Rientjes <rientjes@google.com>
> CC: Jiang Liu <liuj97@gmail.com>
> CC: Len Brown <len.brown@intel.com>
> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> CC: Paul Mackerras <paulus@samba.org>
> CC: Christoph Lameter <cl@linux.com>
> Cc: Minchan Kim <minchan.kim@gmail.com>
> CC: Andrew Morton <akpm@linux-foundation.org>
> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
> 
> ---
>  drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>  drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>  include/linux/memory.h         |    5 +++++
>  include/linux/memory_hotplug.h |    1 +
>  mm/memory_hotplug.c            |    8 ++++++++
>  5 files changed, 77 insertions(+), 1 deletion(-)
> 
> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
> @@ -29,6 +29,7 @@
>  #include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/types.h>
> +#include <linux/memory.h>
>  #include <linux/memory_hotplug.h>
>  #include <linux/slab.h>
>  #include <acpi/acpi_drivers.h>
> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>  static int acpi_memory_device_remove(struct acpi_device *device, int type)
>  {
>  	struct acpi_memory_device *mem_device = NULL;
> -
> +	struct acpi_memory_info *info, *tmp;
> +	int result;
> +	int node;
> 
>  	if (!device || !acpi_driver_data(device))
>  		return -EINVAL;
> 
>  	mem_device = acpi_driver_data(device);
> +
> +	node = acpi_get_node(mem_device->device->handle);
> +
> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
> +		if (!info->enabled)
> +			continue;
> +
> +		if (!is_memblk_offline(info->start_addr, info->length)) {
> +			result = offline_memory(info->start_addr, info->length);
> +			if (result)
> +				return result;
> +		}
> +
> +		result = remove_memory(node, info->start_addr, info->length);
> +		if (result)
> +			return result;
> +
> +		list_del(&info->list);
> +		kfree(info);
> +	}
> +
>  	kfree(mem_device);

The caller does not care the return value, and after this function returns, the
memory device will be unbound from this driver, so we should free all memory
allocated for driver data.

> 
>  	return 0;
> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>  extern int mem_online_node(int nid);
>  extern int add_memory(int nid, u64 start, u64 size);
>  extern int arch_add_memory(int nid, u64 start, u64 size);
> +extern int remove_memory(int nid, u64 start, u64 size);
>  extern int offline_memory(u64 start, u64 size);
>  extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>  								int nr_pages);
> Index: linux-3.5-rc4/mm/memory_hotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
> @@ -659,6 +659,14 @@ out:
>  }
>  EXPORT_SYMBOL_GPL(add_memory);
> 
> +int remove_memory(int nid, u64 start, u64 size)
> +{
> +	return -EBUSY;
> +
> +}
> +EXPORT_SYMBOL_GPL(remove_memory);
> +
> +
>  #ifdef CONFIG_MEMORY_HOTREMOVE
>  /*
>   * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
> Index: linux-3.5-rc4/drivers/base/memory.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>  }
>  EXPORT_SYMBOL(unregister_memory_isolate_notifier);
> 
> +bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	struct memory_block *mem = NULL;
> +	struct mem_section *section;
> +	unsigned long start_pfn, end_pfn;
> +	unsigned long pfn, section_nr;
> +
> +	start_pfn = PFN_DOWN(start);
> +	end_pfn = start_pfn + PFN_DOWN(start);
> +
> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
> +		section_nr = pfn_to_section_nr(pfn);
> +		if (!present_section_nr(section_nr));
> +			continue;
> +
> +		section = __nr_to_section(section_nr);
> +		/* same memblock? */
> +		if (mem)
> +			if((section_nr >= mem->start_section_nr) &&
> +			   (section_nr <= mem->end_section_nr))
> +				continue;
> +
> +		mem = find_memory_block_hinted(section, mem);

The second parameter should be NULL. Otherwise, the mem->dev.kobj will
be put twice:
1. we put it when mem->state is MEM_OFFLINE
2. we put it in find_memory_block_hinted().

Thanks
Wen Congyang

> +		if (!mem)
> +			continue;
> +		if (mem->state == MEM_OFFLINE) {
> +			kobject_put(&mem->dev.kobj);
> +			continue;
> +		}
> +
> +		kobject_put(&mem->dev.kobj);
> +		return false;
> +	}
> +
> +	return true;
> +}
> +EXPORT_SYMBOL(is_memblk_offline);
> +
>  /*
>   * register_memory - Setup a sysfs device for a memory block
>   */
> Index: linux-3.5-rc4/include/linux/memory.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>  {
>  	return 0;
>  }
> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	return false;
> +}
>  #else
>  extern int register_memory_notifier(struct notifier_block *nb);
>  extern void unregister_memory_notifier(struct notifier_block *nb);
> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>  extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>  							struct memory_block *);
>  extern struct memory_block *find_memory_block(struct mem_section *);
> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>  #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>  enum mem_add_context { BOOT, HOTPLUG };
>  #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Wen Congyang]

At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
> acpi_memory_device_remove() has been prepared to remove physical memory.
> But, the function only frees acpi_memory_device currentlry.
> 
> The patch adds following functions into acpi_memory_device_remove():
>   - offline memory
>   - remove physical memory (only return -EBUSY)
>   - free acpi_memory_device
> 
> CC: David Rientjes <rientjes@google.com>
> CC: Jiang Liu <liuj97@gmail.com>
> CC: Len Brown <len.brown@intel.com>
> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> CC: Paul Mackerras <paulus@samba.org>
> CC: Christoph Lameter <cl@linux.com>
> Cc: Minchan Kim <minchan.kim@gmail.com>
> CC: Andrew Morton <akpm@linux-foundation.org>
> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
> 
> ---
>  drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>  drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>  include/linux/memory.h         |    5 +++++
>  include/linux/memory_hotplug.h |    1 +
>  mm/memory_hotplug.c            |    8 ++++++++
>  5 files changed, 77 insertions(+), 1 deletion(-)
> 
> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
> @@ -29,6 +29,7 @@
>  #include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/types.h>
> +#include <linux/memory.h>
>  #include <linux/memory_hotplug.h>
>  #include <linux/slab.h>
>  #include <acpi/acpi_drivers.h>
> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>  static int acpi_memory_device_remove(struct acpi_device *device, int type)
>  {
>  	struct acpi_memory_device *mem_device = NULL;
> -
> +	struct acpi_memory_info *info, *tmp;
> +	int result;
> +	int node;
> 
>  	if (!device || !acpi_driver_data(device))
>  		return -EINVAL;
> 
>  	mem_device = acpi_driver_data(device);
> +
> +	node = acpi_get_node(mem_device->device->handle);
> +
> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
> +		if (!info->enabled)
> +			continue;
> +
> +		if (!is_memblk_offline(info->start_addr, info->length)) {
> +			result = offline_memory(info->start_addr, info->length);
> +			if (result)
> +				return result;
> +		}
> +
> +		result = remove_memory(node, info->start_addr, info->length);
> +		if (result)
> +			return result;
> +
> +		list_del(&info->list);
> +		kfree(info);
> +	}
> +
>  	kfree(mem_device);

The caller does not care the return value, and after this function returns, the
memory device will be unbound from this driver, so we should free all memory
allocated for driver data.

> 
>  	return 0;
> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>  extern int mem_online_node(int nid);
>  extern int add_memory(int nid, u64 start, u64 size);
>  extern int arch_add_memory(int nid, u64 start, u64 size);
> +extern int remove_memory(int nid, u64 start, u64 size);
>  extern int offline_memory(u64 start, u64 size);
>  extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>  								int nr_pages);
> Index: linux-3.5-rc4/mm/memory_hotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
> @@ -659,6 +659,14 @@ out:
>  }
>  EXPORT_SYMBOL_GPL(add_memory);
> 
> +int remove_memory(int nid, u64 start, u64 size)
> +{
> +	return -EBUSY;
> +
> +}
> +EXPORT_SYMBOL_GPL(remove_memory);
> +
> +
>  #ifdef CONFIG_MEMORY_HOTREMOVE
>  /*
>   * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
> Index: linux-3.5-rc4/drivers/base/memory.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>  }
>  EXPORT_SYMBOL(unregister_memory_isolate_notifier);
> 
> +bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	struct memory_block *mem = NULL;
> +	struct mem_section *section;
> +	unsigned long start_pfn, end_pfn;
> +	unsigned long pfn, section_nr;
> +
> +	start_pfn = PFN_DOWN(start);
> +	end_pfn = start_pfn + PFN_DOWN(start);
> +
> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
> +		section_nr = pfn_to_section_nr(pfn);
> +		if (!present_section_nr(section_nr));
> +			continue;
> +
> +		section = __nr_to_section(section_nr);
> +		/* same memblock? */
> +		if (mem)
> +			if((section_nr >= mem->start_section_nr) &&
> +			   (section_nr <= mem->end_section_nr))
> +				continue;
> +
> +		mem = find_memory_block_hinted(section, mem);

The second parameter should be NULL. Otherwise, the mem->dev.kobj will
be put twice:
1. we put it when mem->state is MEM_OFFLINE
2. we put it in find_memory_block_hinted().

Thanks
Wen Congyang

> +		if (!mem)
> +			continue;
> +		if (mem->state == MEM_OFFLINE) {
> +			kobject_put(&mem->dev.kobj);
> +			continue;
> +		}
> +
> +		kobject_put(&mem->dev.kobj);
> +		return false;
> +	}
> +
> +	return true;
> +}
> +EXPORT_SYMBOL(is_memblk_offline);
> +
>  /*
>   * register_memory - Setup a sysfs device for a memory block
>   */
> Index: linux-3.5-rc4/include/linux/memory.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>  {
>  	return 0;
>  }
> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	return false;
> +}
>  #else
>  extern int register_memory_notifier(struct notifier_block *nb);
>  extern void unregister_memory_notifier(struct notifier_block *nb);
> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>  extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>  							struct memory_block *);
>  extern struct memory_block *find_memory_block(struct mem_section *);
> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>  #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>  enum mem_add_context { BOOT, HOTPLUG };
>  #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Wen Congyang]

At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
> acpi_memory_device_remove() has been prepared to remove physical memory.
> But, the function only frees acpi_memory_device currentlry.
> 
> The patch adds following functions into acpi_memory_device_remove():
>   - offline memory
>   - remove physical memory (only return -EBUSY)
>   - free acpi_memory_device
> 
> CC: David Rientjes <rientjes@google.com>
> CC: Jiang Liu <liuj97@gmail.com>
> CC: Len Brown <len.brown@intel.com>
> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> CC: Paul Mackerras <paulus@samba.org>
> CC: Christoph Lameter <cl@linux.com>
> Cc: Minchan Kim <minchan.kim@gmail.com>
> CC: Andrew Morton <akpm@linux-foundation.org>
> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
> 
> ---
>  drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>  drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>  include/linux/memory.h         |    5 +++++
>  include/linux/memory_hotplug.h |    1 +
>  mm/memory_hotplug.c            |    8 ++++++++
>  5 files changed, 77 insertions(+), 1 deletion(-)
> 
> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
> @@ -29,6 +29,7 @@
>  #include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/types.h>
> +#include <linux/memory.h>
>  #include <linux/memory_hotplug.h>
>  #include <linux/slab.h>
>  #include <acpi/acpi_drivers.h>
> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>  static int acpi_memory_device_remove(struct acpi_device *device, int type)
>  {
>  	struct acpi_memory_device *mem_device = NULL;
> -
> +	struct acpi_memory_info *info, *tmp;
> +	int result;
> +	int node;
> 
>  	if (!device || !acpi_driver_data(device))
>  		return -EINVAL;
> 
>  	mem_device = acpi_driver_data(device);
> +
> +	node = acpi_get_node(mem_device->device->handle);
> +
> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
> +		if (!info->enabled)
> +			continue;
> +
> +		if (!is_memblk_offline(info->start_addr, info->length)) {
> +			result = offline_memory(info->start_addr, info->length);
> +			if (result)
> +				return result;
> +		}
> +
> +		result = remove_memory(node, info->start_addr, info->length);
> +		if (result)
> +			return result;
> +
> +		list_del(&info->list);
> +		kfree(info);
> +	}
> +
>  	kfree(mem_device);

The caller does not care the return value, and after this function returns, the
memory device will be unbound from this driver, so we should free all memory
allocated for driver data.

> 
>  	return 0;
> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>  extern int mem_online_node(int nid);
>  extern int add_memory(int nid, u64 start, u64 size);
>  extern int arch_add_memory(int nid, u64 start, u64 size);
> +extern int remove_memory(int nid, u64 start, u64 size);
>  extern int offline_memory(u64 start, u64 size);
>  extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>  								int nr_pages);
> Index: linux-3.5-rc4/mm/memory_hotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
> @@ -659,6 +659,14 @@ out:
>  }
>  EXPORT_SYMBOL_GPL(add_memory);
> 
> +int remove_memory(int nid, u64 start, u64 size)
> +{
> +	return -EBUSY;
> +
> +}
> +EXPORT_SYMBOL_GPL(remove_memory);
> +
> +
>  #ifdef CONFIG_MEMORY_HOTREMOVE
>  /*
>   * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
> Index: linux-3.5-rc4/drivers/base/memory.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>  }
>  EXPORT_SYMBOL(unregister_memory_isolate_notifier);
> 
> +bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	struct memory_block *mem = NULL;
> +	struct mem_section *section;
> +	unsigned long start_pfn, end_pfn;
> +	unsigned long pfn, section_nr;
> +
> +	start_pfn = PFN_DOWN(start);
> +	end_pfn = start_pfn + PFN_DOWN(start);
> +
> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
> +		section_nr = pfn_to_section_nr(pfn);
> +		if (!present_section_nr(section_nr));
> +			continue;
> +
> +		section = __nr_to_section(section_nr);
> +		/* same memblock? */
> +		if (mem)
> +			if((section_nr >= mem->start_section_nr) &&
> +			   (section_nr <= mem->end_section_nr))
> +				continue;
> +
> +		mem = find_memory_block_hinted(section, mem);

The second parameter should be NULL. Otherwise, the mem->dev.kobj will
be put twice:
1. we put it when mem->state is MEM_OFFLINE
2. we put it in find_memory_block_hinted().

Thanks
Wen Congyang

> +		if (!mem)
> +			continue;
> +		if (mem->state == MEM_OFFLINE) {
> +			kobject_put(&mem->dev.kobj);
> +			continue;
> +		}
> +
> +		kobject_put(&mem->dev.kobj);
> +		return false;
> +	}
> +
> +	return true;
> +}
> +EXPORT_SYMBOL(is_memblk_offline);
> +
>  /*
>   * register_memory - Setup a sysfs device for a memory block
>   */
> Index: linux-3.5-rc4/include/linux/memory.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>  {
>  	return 0;
>  }
> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	return false;
> +}
>  #else
>  extern int register_memory_notifier(struct notifier_block *nb);
>  extern void unregister_memory_notifier(struct notifier_block *nb);
> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>  extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>  							struct memory_block *);
>  extern struct memory_block *find_memory_block(struct mem_section *);
> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>  #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>  enum mem_add_context { BOOT, HOTPLUG };
>  #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
> sysfs files are created. But there is no code to remove these files. The patch
> implements the function to remove them.
> 
> Note : The code does not free firmware_map_entry since there is no way to free
>        memory which is allocated by bootmem.
> 
> CC: David Rientjes <rientjes@google.com>
> CC: Jiang Liu <liuj97@gmail.com>
> CC: Len Brown <len.brown@intel.com>
> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> CC: Paul Mackerras <paulus@samba.org>
> CC: Christoph Lameter <cl@linux.com>
> Cc: Minchan Kim <minchan.kim@gmail.com>
> CC: Andrew Morton <akpm@linux-foundation.org>
> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
> 
> ---
>  drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>  include/linux/firmware-map.h |    6 +++
>  mm/memory_hotplug.c          |    6 +++
>  3 files changed, 81 insertions(+), 1 deletion(-)
> 
> Index: linux-3.5-rc4/mm/memory_hotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
> 
>  int remove_memory(int nid, u64 start, u64 size)
>  {
> -	return -EBUSY;
> +	lock_memory_hotplug();
> +	/* remove memmap entry */
> +	firmware_map_remove(start, start + size - 1, "System RAM");
> +	unlock_memory_hotplug();
> +	return 0;
> 
>  }
>  EXPORT_SYMBOL_GPL(remove_memory);
> Index: linux-3.5-rc4/include/linux/firmware-map.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
> @@ -25,6 +25,7 @@
> 
>  int firmware_map_add_early(u64 start, u64 end, const char *type);
>  int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
> +int firmware_map_remove(u64 start, u64 end, const char *type);
> 
>  #else /* CONFIG_FIRMWARE_MEMMAP */
> 
> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>  	return 0;
>  }
> 
> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
> +{
> +	return 0;
> +}
> +
>  #endif /* CONFIG_FIRMWARE_MEMMAP */
> 
>  #endif /* _LINUX_FIRMWARE_MAP_H */
> Index: linux-3.5-rc4/drivers/firmware/memmap.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>  	.show = memmap_attr_show,
>  };
> 
> +static void release_firmware_map_entry(struct kobject *kobj)
> +{
> +	/*
> +	 * FIXME : There is no idea.
> +	 *         How to free the entry which allocated bootmem?
> +	 */

I find a function free_bootmem(), but I am not sure whether it can work here.
Another problem: how to check whether the entry uses bootmem?

Thanks
Wen Congyang

> +}
> +
>  static struct kobj_type memmap_ktype = {
> +	.release	= release_firmware_map_entry,
>  	.sysfs_ops	= &memmap_attr_ops,
>  	.default_attrs	= def_attrs,
>  };
> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>  	return 0;
>  }
> 
> +/**
> + * firmware_map_remove_entry() - Does the real work to remove a firmware
> + * memmap entry.
> + * @entry: removed entry.
> + **/
> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
> +{
> +	list_del(&entry->list);
> +}
> +
>  /*
>   * Add memmap entry on sysfs
>   */
> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>  	return 0;
>  }
> 
> +/*
> + * Remove memmap entry on sysfs
> + */
> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
> +{
> +	kobject_put(&entry->kobj);
> +}
> +
> +/*
> + * Search memmap entry
> + */
> +
> +struct firmware_map_entry * __meminit
> +find_firmware_map_entry(u64 start, u64 end, const char *type)
> +{
> +	struct firmware_map_entry *entry;
> +
> +	list_for_each_entry(entry, &map_entries, list)
> +		if ((entry->start == start) && (entry->end == end) &&
> +		    (!strcmp(entry->type, type)))
> +			return entry;
> +
> +	return NULL;
> +}
> +
>  /**
>   * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>   * memory hotplug.
> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>  	return firmware_map_add_entry(start, end, type, entry);
>  }
> 
> +/**
> + * firmware_map_remove() - remove a firmware mapping entry
> + * @start: Start of the memory range.
> + * @end:   End of the memory range (inclusive).
> + * @type:  Type of the memory range.
> + *
> + * removes a firmware mapping entry.
> + *
> + * Returns 0 on success, or -EINVAL if no entry.
> + **/
> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
> +{
> +	struct firmware_map_entry *entry;
> +
> +	entry = find_firmware_map_entry(start, end, type);
> +	if (!entry)
> +		return -EINVAL;
> +
> +	/* remove the memmap entry */
> +	remove_sysfs_fw_map_entry(entry);
> +
> +	firmware_map_remove_entry(entry);
> +
> +	return 0;
> +}
> +
>  /*
>   * Sysfs functions -------------------------------------------------------------
>   */
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
> sysfs files are created. But there is no code to remove these files. The patch
> implements the function to remove them.
> 
> Note : The code does not free firmware_map_entry since there is no way to free
>        memory which is allocated by bootmem.
> 
> CC: David Rientjes <rientjes@google.com>
> CC: Jiang Liu <liuj97@gmail.com>
> CC: Len Brown <len.brown@intel.com>
> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> CC: Paul Mackerras <paulus@samba.org>
> CC: Christoph Lameter <cl@linux.com>
> Cc: Minchan Kim <minchan.kim@gmail.com>
> CC: Andrew Morton <akpm@linux-foundation.org>
> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
> 
> ---
>  drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>  include/linux/firmware-map.h |    6 +++
>  mm/memory_hotplug.c          |    6 +++
>  3 files changed, 81 insertions(+), 1 deletion(-)
> 
> Index: linux-3.5-rc4/mm/memory_hotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
> 
>  int remove_memory(int nid, u64 start, u64 size)
>  {
> -	return -EBUSY;
> +	lock_memory_hotplug();
> +	/* remove memmap entry */
> +	firmware_map_remove(start, start + size - 1, "System RAM");
> +	unlock_memory_hotplug();
> +	return 0;
> 
>  }
>  EXPORT_SYMBOL_GPL(remove_memory);
> Index: linux-3.5-rc4/include/linux/firmware-map.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
> @@ -25,6 +25,7 @@
> 
>  int firmware_map_add_early(u64 start, u64 end, const char *type);
>  int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
> +int firmware_map_remove(u64 start, u64 end, const char *type);
> 
>  #else /* CONFIG_FIRMWARE_MEMMAP */
> 
> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>  	return 0;
>  }
> 
> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
> +{
> +	return 0;
> +}
> +
>  #endif /* CONFIG_FIRMWARE_MEMMAP */
> 
>  #endif /* _LINUX_FIRMWARE_MAP_H */
> Index: linux-3.5-rc4/drivers/firmware/memmap.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>  	.show = memmap_attr_show,
>  };
> 
> +static void release_firmware_map_entry(struct kobject *kobj)
> +{
> +	/*
> +	 * FIXME : There is no idea.
> +	 *         How to free the entry which allocated bootmem?
> +	 */

I find a function free_bootmem(), but I am not sure whether it can work here.
Another problem: how to check whether the entry uses bootmem?

Thanks
Wen Congyang

> +}
> +
>  static struct kobj_type memmap_ktype = {
> +	.release	= release_firmware_map_entry,
>  	.sysfs_ops	= &memmap_attr_ops,
>  	.default_attrs	= def_attrs,
>  };
> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>  	return 0;
>  }
> 
> +/**
> + * firmware_map_remove_entry() - Does the real work to remove a firmware
> + * memmap entry.
> + * @entry: removed entry.
> + **/
> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
> +{
> +	list_del(&entry->list);
> +}
> +
>  /*
>   * Add memmap entry on sysfs
>   */
> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>  	return 0;
>  }
> 
> +/*
> + * Remove memmap entry on sysfs
> + */
> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
> +{
> +	kobject_put(&entry->kobj);
> +}
> +
> +/*
> + * Search memmap entry
> + */
> +
> +struct firmware_map_entry * __meminit
> +find_firmware_map_entry(u64 start, u64 end, const char *type)
> +{
> +	struct firmware_map_entry *entry;
> +
> +	list_for_each_entry(entry, &map_entries, list)
> +		if ((entry->start == start) && (entry->end == end) &&
> +		    (!strcmp(entry->type, type)))
> +			return entry;
> +
> +	return NULL;
> +}
> +
>  /**
>   * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>   * memory hotplug.
> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>  	return firmware_map_add_entry(start, end, type, entry);
>  }
> 
> +/**
> + * firmware_map_remove() - remove a firmware mapping entry
> + * @start: Start of the memory range.
> + * @end:   End of the memory range (inclusive).
> + * @type:  Type of the memory range.
> + *
> + * removes a firmware mapping entry.
> + *
> + * Returns 0 on success, or -EINVAL if no entry.
> + **/
> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
> +{
> +	struct firmware_map_entry *entry;
> +
> +	entry = find_firmware_map_entry(start, end, type);
> +	if (!entry)
> +		return -EINVAL;
> +
> +	/* remove the memmap entry */
> +	remove_sysfs_fw_map_entry(entry);
> +
> +	firmware_map_remove_entry(entry);
> +
> +	return 0;
> +}
> +
>  /*
>   * Sysfs functions -------------------------------------------------------------
>   */
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
> sysfs files are created. But there is no code to remove these files. The patch
> implements the function to remove them.
> 
> Note : The code does not free firmware_map_entry since there is no way to free
>        memory which is allocated by bootmem.
> 
> CC: David Rientjes <rientjes@google.com>
> CC: Jiang Liu <liuj97@gmail.com>
> CC: Len Brown <len.brown@intel.com>
> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> CC: Paul Mackerras <paulus@samba.org>
> CC: Christoph Lameter <cl@linux.com>
> Cc: Minchan Kim <minchan.kim@gmail.com>
> CC: Andrew Morton <akpm@linux-foundation.org>
> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
> 
> ---
>  drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>  include/linux/firmware-map.h |    6 +++
>  mm/memory_hotplug.c          |    6 +++
>  3 files changed, 81 insertions(+), 1 deletion(-)
> 
> Index: linux-3.5-rc4/mm/memory_hotplug.c
> ===================================================================
> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
> 
>  int remove_memory(int nid, u64 start, u64 size)
>  {
> -	return -EBUSY;
> +	lock_memory_hotplug();
> +	/* remove memmap entry */
> +	firmware_map_remove(start, start + size - 1, "System RAM");
> +	unlock_memory_hotplug();
> +	return 0;
> 
>  }
>  EXPORT_SYMBOL_GPL(remove_memory);
> Index: linux-3.5-rc4/include/linux/firmware-map.h
> ===================================================================
> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
> @@ -25,6 +25,7 @@
> 
>  int firmware_map_add_early(u64 start, u64 end, const char *type);
>  int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
> +int firmware_map_remove(u64 start, u64 end, const char *type);
> 
>  #else /* CONFIG_FIRMWARE_MEMMAP */
> 
> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>  	return 0;
>  }
> 
> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
> +{
> +	return 0;
> +}
> +
>  #endif /* CONFIG_FIRMWARE_MEMMAP */
> 
>  #endif /* _LINUX_FIRMWARE_MAP_H */
> Index: linux-3.5-rc4/drivers/firmware/memmap.c
> ===================================================================
> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>  	.show = memmap_attr_show,
>  };
> 
> +static void release_firmware_map_entry(struct kobject *kobj)
> +{
> +	/*
> +	 * FIXME : There is no idea.
> +	 *         How to free the entry which allocated bootmem?
> +	 */

I find a function free_bootmem(), but I am not sure whether it can work here.
Another problem: how to check whether the entry uses bootmem?

Thanks
Wen Congyang

> +}
> +
>  static struct kobj_type memmap_ktype = {
> +	.release	= release_firmware_map_entry,
>  	.sysfs_ops	= &memmap_attr_ops,
>  	.default_attrs	= def_attrs,
>  };
> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>  	return 0;
>  }
> 
> +/**
> + * firmware_map_remove_entry() - Does the real work to remove a firmware
> + * memmap entry.
> + * @entry: removed entry.
> + **/
> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
> +{
> +	list_del(&entry->list);
> +}
> +
>  /*
>   * Add memmap entry on sysfs
>   */
> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>  	return 0;
>  }
> 
> +/*
> + * Remove memmap entry on sysfs
> + */
> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
> +{
> +	kobject_put(&entry->kobj);
> +}
> +
> +/*
> + * Search memmap entry
> + */
> +
> +struct firmware_map_entry * __meminit
> +find_firmware_map_entry(u64 start, u64 end, const char *type)
> +{
> +	struct firmware_map_entry *entry;
> +
> +	list_for_each_entry(entry, &map_entries, list)
> +		if ((entry->start == start) && (entry->end == end) &&
> +		    (!strcmp(entry->type, type)))
> +			return entry;
> +
> +	return NULL;
> +}
> +
>  /**
>   * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>   * memory hotplug.
> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>  	return firmware_map_add_entry(start, end, type, entry);
>  }
> 
> +/**
> + * firmware_map_remove() - remove a firmware mapping entry
> + * @start: Start of the memory range.
> + * @end:   End of the memory range (inclusive).
> + * @type:  Type of the memory range.
> + *
> + * removes a firmware mapping entry.
> + *
> + * Returns 0 on success, or -EINVAL if no entry.
> + **/
> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
> +{
> +	struct firmware_map_entry *entry;
> +
> +	entry = find_firmware_map_entry(start, end, type);
> +	if (!entry)
> +		return -EINVAL;
> +
> +	/* remove the memmap entry */
> +	remove_sysfs_fw_map_entry(entry);
> +
> +	firmware_map_remove_entry(entry);
> +
> +	return 0;
> +}
> +
>  /*
>   * Sysfs functions -------------------------------------------------------------
>   */
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/03 15:21, Wen Congyang wrote:
> At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
>> acpi_memory_device_remove() has been prepared to remove physical memory.
>> But, the function only frees acpi_memory_device currentlry.
>>
>> The patch adds following functions into acpi_memory_device_remove():
>>    - offline memory
>>    - remove physical memory (only return -EBUSY)
>>    - free acpi_memory_device
>>
>> CC: David Rientjes <rientjes@google.com>
>> CC: Jiang Liu <liuj97@gmail.com>
>> CC: Len Brown <len.brown@intel.com>
>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> CC: Paul Mackerras <paulus@samba.org>
>> CC: Christoph Lameter <cl@linux.com>
>> Cc: Minchan Kim <minchan.kim@gmail.com>
>> CC: Andrew Morton <akpm@linux-foundation.org>
>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>
>> ---
>>   drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>>   drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>>   include/linux/memory.h         |    5 +++++
>>   include/linux/memory_hotplug.h |    1 +
>>   mm/memory_hotplug.c            |    8 ++++++++
>>   5 files changed, 77 insertions(+), 1 deletion(-)
>>
>> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
>> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
>> @@ -29,6 +29,7 @@
>>   #include <linux/module.h>
>>   #include <linux/init.h>
>>   #include <linux/types.h>
>> +#include <linux/memory.h>
>>   #include <linux/memory_hotplug.h>
>>   #include <linux/slab.h>
>>   #include <acpi/acpi_drivers.h>
>> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>>   static int acpi_memory_device_remove(struct acpi_device *device, int type)
>>   {
>>   	struct acpi_memory_device *mem_device = NULL;
>> -
>> +	struct acpi_memory_info *info, *tmp;
>> +	int result;
>> +	int node;
>>
>>   	if (!device || !acpi_driver_data(device))
>>   		return -EINVAL;
>>
>>   	mem_device = acpi_driver_data(device);
>> +
>> +	node = acpi_get_node(mem_device->device->handle);
>> +
>> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
>> +		if (!info->enabled)
>> +			continue;
>> +
>> +		if (!is_memblk_offline(info->start_addr, info->length)) {
>> +			result = offline_memory(info->start_addr, info->length);
>> +			if (result)
>> +				return result;
>> +		}
>> +
>> +		result = remove_memory(node, info->start_addr, info->length);
>> +		if (result)
>> +			return result;
>> +
>> +		list_del(&info->list);
>> +		kfree(info);
>> +	}
>> +
>>   	kfree(mem_device);
> 
> The caller does not care the return value, and after this function returns, the
> memory device will be unbound from this driver, so we should free all memory
> allocated for driver data.

We can ignore return value of remove_memory() because I think that it should
return 0. But we cannot ignore return value of offline_memory() because
kernel panic will occurs if kernel removes online memory. How do we deal with
online memory?

>>
>>   	return 0;
>> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
>> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
>> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>>   extern int mem_online_node(int nid);
>>   extern int add_memory(int nid, u64 start, u64 size);
>>   extern int arch_add_memory(int nid, u64 start, u64 size);
>> +extern int remove_memory(int nid, u64 start, u64 size);
>>   extern int offline_memory(u64 start, u64 size);
>>   extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>>   								int nr_pages);
>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
>> @@ -659,6 +659,14 @@ out:
>>   }
>>   EXPORT_SYMBOL_GPL(add_memory);
>>
>> +int remove_memory(int nid, u64 start, u64 size)
>> +{
>> +	return -EBUSY;
>> +
>> +}
>> +EXPORT_SYMBOL_GPL(remove_memory);
>> +
>> +
>>   #ifdef CONFIG_MEMORY_HOTREMOVE
>>   /*
>>    * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
>> Index: linux-3.5-rc4/drivers/base/memory.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
>> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
>> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>>   }
>>   EXPORT_SYMBOL(unregister_memory_isolate_notifier);
>>
>> +bool is_memblk_offline(unsigned long start, unsigned long size)
>> +{
>> +	struct memory_block *mem = NULL;
>> +	struct mem_section *section;
>> +	unsigned long start_pfn, end_pfn;
>> +	unsigned long pfn, section_nr;
>> +
>> +	start_pfn = PFN_DOWN(start);
>> +	end_pfn = start_pfn + PFN_DOWN(start);
>> +
>> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
>> +		section_nr = pfn_to_section_nr(pfn);
>> +		if (!present_section_nr(section_nr));
>> +			continue;
>> +
>> +		section = __nr_to_section(section_nr);
>> +		/* same memblock? */
>> +		if (mem)
>> +			if((section_nr >= mem->start_section_nr) &&
>> +			   (section_nr <= mem->end_section_nr))
>> +				continue;
>> +
>> +		mem = find_memory_block_hinted(section, mem);
> 
> The second parameter should be NULL. Otherwise, the mem->dev.kobj will
> be put twice:
> 1. we put it when mem->state is MEM_OFFLINE
> 2. we put it in find_memory_block_hinted().

Ah, O.K.
How about it?

+bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	struct memory_block *mem = NULL;
+	struct mem_section *section;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pfn, section_nr;
+
+	start_pfn = PFN_DOWN(start);
+	end_pfn = start_pfn + PFN_DOWN(start);
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		section_nr = pfn_to_section_nr(pfn);
+		if (!present_section_nr(section_nr));
+			continue;
+
+		section = __nr_to_section(section_nr);
+		/* same memblock? */
+		if (mem)
+			if((section_nr >= mem->start_section_nr) &&
+			   (section_nr <= mem->end_section_nr))
+				continue;
+
+		mem = find_memory_block_hinted(section, mem);
+		if (!mem)
+			continue;
+		if (mem->state == MEM_OFFLINE)
+			continue;
+
+		kobject_put(&mem->dev.kobj);
+		return false;
+	}
+
+	if (mem)
+		kobject_put(&mem->dev.kobj);
+
+	return true;
+}
+EXPORT_SYMBOL(is_memblk_offline);

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang
> 
>> +		if (!mem)
>> +			continue;
>> +		if (mem->state == MEM_OFFLINE) {
>> +			kobject_put(&mem->dev.kobj);
>> +			continue;
>> +		}
>> +
>> +		kobject_put(&mem->dev.kobj);
>> +		return false;
>> +	}
>> +
>> +	return true;
>> +}
>> +EXPORT_SYMBOL(is_memblk_offline);
>> +
>>   /*
>>    * register_memory - Setup a sysfs device for a memory block
>>    */
>> Index: linux-3.5-rc4/include/linux/memory.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
>> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
>> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>>   {
>>   	return 0;
>>   }
>> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
>> +{
>> +	return false;
>> +}
>>   #else
>>   extern int register_memory_notifier(struct notifier_block *nb);
>>   extern void unregister_memory_notifier(struct notifier_block *nb);
>> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>>   extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>>   							struct memory_block *);
>>   extern struct memory_block *find_memory_block(struct mem_section *);
>> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>>   #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>>   enum mem_add_context { BOOT, HOTPLUG };
>>   #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/03 15:21, Wen Congyang wrote:
> At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
>> acpi_memory_device_remove() has been prepared to remove physical memory.
>> But, the function only frees acpi_memory_device currentlry.
>>
>> The patch adds following functions into acpi_memory_device_remove():
>>    - offline memory
>>    - remove physical memory (only return -EBUSY)
>>    - free acpi_memory_device
>>
>> CC: David Rientjes <rientjes@google.com>
>> CC: Jiang Liu <liuj97@gmail.com>
>> CC: Len Brown <len.brown@intel.com>
>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> CC: Paul Mackerras <paulus@samba.org>
>> CC: Christoph Lameter <cl@linux.com>
>> Cc: Minchan Kim <minchan.kim@gmail.com>
>> CC: Andrew Morton <akpm@linux-foundation.org>
>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>
>> ---
>>   drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>>   drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>>   include/linux/memory.h         |    5 +++++
>>   include/linux/memory_hotplug.h |    1 +
>>   mm/memory_hotplug.c            |    8 ++++++++
>>   5 files changed, 77 insertions(+), 1 deletion(-)
>>
>> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
>> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
>> @@ -29,6 +29,7 @@
>>   #include <linux/module.h>
>>   #include <linux/init.h>
>>   #include <linux/types.h>
>> +#include <linux/memory.h>
>>   #include <linux/memory_hotplug.h>
>>   #include <linux/slab.h>
>>   #include <acpi/acpi_drivers.h>
>> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>>   static int acpi_memory_device_remove(struct acpi_device *device, int type)
>>   {
>>   	struct acpi_memory_device *mem_device = NULL;
>> -
>> +	struct acpi_memory_info *info, *tmp;
>> +	int result;
>> +	int node;
>>
>>   	if (!device || !acpi_driver_data(device))
>>   		return -EINVAL;
>>
>>   	mem_device = acpi_driver_data(device);
>> +
>> +	node = acpi_get_node(mem_device->device->handle);
>> +
>> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
>> +		if (!info->enabled)
>> +			continue;
>> +
>> +		if (!is_memblk_offline(info->start_addr, info->length)) {
>> +			result = offline_memory(info->start_addr, info->length);
>> +			if (result)
>> +				return result;
>> +		}
>> +
>> +		result = remove_memory(node, info->start_addr, info->length);
>> +		if (result)
>> +			return result;
>> +
>> +		list_del(&info->list);
>> +		kfree(info);
>> +	}
>> +
>>   	kfree(mem_device);
> 
> The caller does not care the return value, and after this function returns, the
> memory device will be unbound from this driver, so we should free all memory
> allocated for driver data.

We can ignore return value of remove_memory() because I think that it should
return 0. But we cannot ignore return value of offline_memory() because
kernel panic will occurs if kernel removes online memory. How do we deal with
online memory?

>>
>>   	return 0;
>> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
>> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
>> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>>   extern int mem_online_node(int nid);
>>   extern int add_memory(int nid, u64 start, u64 size);
>>   extern int arch_add_memory(int nid, u64 start, u64 size);
>> +extern int remove_memory(int nid, u64 start, u64 size);
>>   extern int offline_memory(u64 start, u64 size);
>>   extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>>   								int nr_pages);
>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
>> @@ -659,6 +659,14 @@ out:
>>   }
>>   EXPORT_SYMBOL_GPL(add_memory);
>>
>> +int remove_memory(int nid, u64 start, u64 size)
>> +{
>> +	return -EBUSY;
>> +
>> +}
>> +EXPORT_SYMBOL_GPL(remove_memory);
>> +
>> +
>>   #ifdef CONFIG_MEMORY_HOTREMOVE
>>   /*
>>    * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
>> Index: linux-3.5-rc4/drivers/base/memory.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
>> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
>> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>>   }
>>   EXPORT_SYMBOL(unregister_memory_isolate_notifier);
>>
>> +bool is_memblk_offline(unsigned long start, unsigned long size)
>> +{
>> +	struct memory_block *mem = NULL;
>> +	struct mem_section *section;
>> +	unsigned long start_pfn, end_pfn;
>> +	unsigned long pfn, section_nr;
>> +
>> +	start_pfn = PFN_DOWN(start);
>> +	end_pfn = start_pfn + PFN_DOWN(start);
>> +
>> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
>> +		section_nr = pfn_to_section_nr(pfn);
>> +		if (!present_section_nr(section_nr));
>> +			continue;
>> +
>> +		section = __nr_to_section(section_nr);
>> +		/* same memblock? */
>> +		if (mem)
>> +			if((section_nr >= mem->start_section_nr) &&
>> +			   (section_nr <= mem->end_section_nr))
>> +				continue;
>> +
>> +		mem = find_memory_block_hinted(section, mem);
> 
> The second parameter should be NULL. Otherwise, the mem->dev.kobj will
> be put twice:
> 1. we put it when mem->state is MEM_OFFLINE
> 2. we put it in find_memory_block_hinted().

Ah, O.K.
How about it?

+bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	struct memory_block *mem = NULL;
+	struct mem_section *section;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pfn, section_nr;
+
+	start_pfn = PFN_DOWN(start);
+	end_pfn = start_pfn + PFN_DOWN(start);
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		section_nr = pfn_to_section_nr(pfn);
+		if (!present_section_nr(section_nr));
+			continue;
+
+		section = __nr_to_section(section_nr);
+		/* same memblock? */
+		if (mem)
+			if((section_nr >= mem->start_section_nr) &&
+			   (section_nr <= mem->end_section_nr))
+				continue;
+
+		mem = find_memory_block_hinted(section, mem);
+		if (!mem)
+			continue;
+		if (mem->state == MEM_OFFLINE)
+			continue;
+
+		kobject_put(&mem->dev.kobj);
+		return false;
+	}
+
+	if (mem)
+		kobject_put(&mem->dev.kobj);
+
+	return true;
+}
+EXPORT_SYMBOL(is_memblk_offline);

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang
> 
>> +		if (!mem)
>> +			continue;
>> +		if (mem->state == MEM_OFFLINE) {
>> +			kobject_put(&mem->dev.kobj);
>> +			continue;
>> +		}
>> +
>> +		kobject_put(&mem->dev.kobj);
>> +		return false;
>> +	}
>> +
>> +	return true;
>> +}
>> +EXPORT_SYMBOL(is_memblk_offline);
>> +
>>   /*
>>    * register_memory - Setup a sysfs device for a memory block
>>    */
>> Index: linux-3.5-rc4/include/linux/memory.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
>> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
>> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>>   {
>>   	return 0;
>>   }
>> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
>> +{
>> +	return false;
>> +}
>>   #else
>>   extern int register_memory_notifier(struct notifier_block *nb);
>>   extern void unregister_memory_notifier(struct notifier_block *nb);
>> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>>   extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>>   							struct memory_block *);
>>   extern struct memory_block *find_memory_block(struct mem_section *);
>> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>>   #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>>   enum mem_add_context { BOOT, HOTPLUG };
>>   #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/03 15:21, Wen Congyang wrote:
> At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
>> acpi_memory_device_remove() has been prepared to remove physical memory.
>> But, the function only frees acpi_memory_device currentlry.
>>
>> The patch adds following functions into acpi_memory_device_remove():
>>    - offline memory
>>    - remove physical memory (only return -EBUSY)
>>    - free acpi_memory_device
>>
>> CC: David Rientjes <rientjes@google.com>
>> CC: Jiang Liu <liuj97@gmail.com>
>> CC: Len Brown <len.brown@intel.com>
>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> CC: Paul Mackerras <paulus@samba.org>
>> CC: Christoph Lameter <cl@linux.com>
>> Cc: Minchan Kim <minchan.kim@gmail.com>
>> CC: Andrew Morton <akpm@linux-foundation.org>
>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>
>> ---
>>   drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>>   drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>>   include/linux/memory.h         |    5 +++++
>>   include/linux/memory_hotplug.h |    1 +
>>   mm/memory_hotplug.c            |    8 ++++++++
>>   5 files changed, 77 insertions(+), 1 deletion(-)
>>
>> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
>> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
>> @@ -29,6 +29,7 @@
>>   #include <linux/module.h>
>>   #include <linux/init.h>
>>   #include <linux/types.h>
>> +#include <linux/memory.h>
>>   #include <linux/memory_hotplug.h>
>>   #include <linux/slab.h>
>>   #include <acpi/acpi_drivers.h>
>> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>>   static int acpi_memory_device_remove(struct acpi_device *device, int type)
>>   {
>>   	struct acpi_memory_device *mem_device = NULL;
>> -
>> +	struct acpi_memory_info *info, *tmp;
>> +	int result;
>> +	int node;
>>
>>   	if (!device || !acpi_driver_data(device))
>>   		return -EINVAL;
>>
>>   	mem_device = acpi_driver_data(device);
>> +
>> +	node = acpi_get_node(mem_device->device->handle);
>> +
>> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
>> +		if (!info->enabled)
>> +			continue;
>> +
>> +		if (!is_memblk_offline(info->start_addr, info->length)) {
>> +			result = offline_memory(info->start_addr, info->length);
>> +			if (result)
>> +				return result;
>> +		}
>> +
>> +		result = remove_memory(node, info->start_addr, info->length);
>> +		if (result)
>> +			return result;
>> +
>> +		list_del(&info->list);
>> +		kfree(info);
>> +	}
>> +
>>   	kfree(mem_device);
> 
> The caller does not care the return value, and after this function returns, the
> memory device will be unbound from this driver, so we should free all memory
> allocated for driver data.

We can ignore return value of remove_memory() because I think that it should
return 0. But we cannot ignore return value of offline_memory() because
kernel panic will occurs if kernel removes online memory. How do we deal with
online memory?

>>
>>   	return 0;
>> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
>> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
>> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>>   extern int mem_online_node(int nid);
>>   extern int add_memory(int nid, u64 start, u64 size);
>>   extern int arch_add_memory(int nid, u64 start, u64 size);
>> +extern int remove_memory(int nid, u64 start, u64 size);
>>   extern int offline_memory(u64 start, u64 size);
>>   extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>>   								int nr_pages);
>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
>> @@ -659,6 +659,14 @@ out:
>>   }
>>   EXPORT_SYMBOL_GPL(add_memory);
>>
>> +int remove_memory(int nid, u64 start, u64 size)
>> +{
>> +	return -EBUSY;
>> +
>> +}
>> +EXPORT_SYMBOL_GPL(remove_memory);
>> +
>> +
>>   #ifdef CONFIG_MEMORY_HOTREMOVE
>>   /*
>>    * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
>> Index: linux-3.5-rc4/drivers/base/memory.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
>> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
>> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>>   }
>>   EXPORT_SYMBOL(unregister_memory_isolate_notifier);
>>
>> +bool is_memblk_offline(unsigned long start, unsigned long size)
>> +{
>> +	struct memory_block *mem = NULL;
>> +	struct mem_section *section;
>> +	unsigned long start_pfn, end_pfn;
>> +	unsigned long pfn, section_nr;
>> +
>> +	start_pfn = PFN_DOWN(start);
>> +	end_pfn = start_pfn + PFN_DOWN(start);
>> +
>> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
>> +		section_nr = pfn_to_section_nr(pfn);
>> +		if (!present_section_nr(section_nr));
>> +			continue;
>> +
>> +		section = __nr_to_section(section_nr);
>> +		/* same memblock? */
>> +		if (mem)
>> +			if((section_nr >= mem->start_section_nr) &&
>> +			   (section_nr <= mem->end_section_nr))
>> +				continue;
>> +
>> +		mem = find_memory_block_hinted(section, mem);
> 
> The second parameter should be NULL. Otherwise, the mem->dev.kobj will
> be put twice:
> 1. we put it when mem->state is MEM_OFFLINE
> 2. we put it in find_memory_block_hinted().

Ah, O.K.
How about it?

+bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	struct memory_block *mem = NULL;
+	struct mem_section *section;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pfn, section_nr;
+
+	start_pfn = PFN_DOWN(start);
+	end_pfn = start_pfn + PFN_DOWN(start);
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		section_nr = pfn_to_section_nr(pfn);
+		if (!present_section_nr(section_nr));
+			continue;
+
+		section = __nr_to_section(section_nr);
+		/* same memblock? */
+		if (mem)
+			if((section_nr >= mem->start_section_nr) &&
+			   (section_nr <= mem->end_section_nr))
+				continue;
+
+		mem = find_memory_block_hinted(section, mem);
+		if (!mem)
+			continue;
+		if (mem->state == MEM_OFFLINE)
+			continue;
+
+		kobject_put(&mem->dev.kobj);
+		return false;
+	}
+
+	if (mem)
+		kobject_put(&mem->dev.kobj);
+
+	return true;
+}
+EXPORT_SYMBOL(is_memblk_offline);

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang
> 
>> +		if (!mem)
>> +			continue;
>> +		if (mem->state == MEM_OFFLINE) {
>> +			kobject_put(&mem->dev.kobj);
>> +			continue;
>> +		}
>> +
>> +		kobject_put(&mem->dev.kobj);
>> +		return false;
>> +	}
>> +
>> +	return true;
>> +}
>> +EXPORT_SYMBOL(is_memblk_offline);
>> +
>>   /*
>>    * register_memory - Setup a sysfs device for a memory block
>>    */
>> Index: linux-3.5-rc4/include/linux/memory.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
>> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
>> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>>   {
>>   	return 0;
>>   }
>> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
>> +{
>> +	return false;
>> +}
>>   #else
>>   extern int register_memory_notifier(struct notifier_block *nb);
>>   extern void unregister_memory_notifier(struct notifier_block *nb);
>> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>>   extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>>   							struct memory_block *);
>>   extern struct memory_block *find_memory_block(struct mem_section *);
>> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>>   #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>>   enum mem_add_context { BOOT, HOTPLUG };
>>   #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 



--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/03 15:21, Wen Congyang wrote:
> At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
>> acpi_memory_device_remove() has been prepared to remove physical memory.
>> But, the function only frees acpi_memory_device currentlry.
>>
>> The patch adds following functions into acpi_memory_device_remove():
>>    - offline memory
>>    - remove physical memory (only return -EBUSY)
>>    - free acpi_memory_device
>>
>> CC: David Rientjes <rientjes@google.com>
>> CC: Jiang Liu <liuj97@gmail.com>
>> CC: Len Brown <len.brown@intel.com>
>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> CC: Paul Mackerras <paulus@samba.org>
>> CC: Christoph Lameter <cl@linux.com>
>> Cc: Minchan Kim <minchan.kim@gmail.com>
>> CC: Andrew Morton <akpm@linux-foundation.org>
>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>
>> ---
>>   drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>>   drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>>   include/linux/memory.h         |    5 +++++
>>   include/linux/memory_hotplug.h |    1 +
>>   mm/memory_hotplug.c            |    8 ++++++++
>>   5 files changed, 77 insertions(+), 1 deletion(-)
>>
>> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
>> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
>> @@ -29,6 +29,7 @@
>>   #include <linux/module.h>
>>   #include <linux/init.h>
>>   #include <linux/types.h>
>> +#include <linux/memory.h>
>>   #include <linux/memory_hotplug.h>
>>   #include <linux/slab.h>
>>   #include <acpi/acpi_drivers.h>
>> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>>   static int acpi_memory_device_remove(struct acpi_device *device, int type)
>>   {
>>   	struct acpi_memory_device *mem_device = NULL;
>> -
>> +	struct acpi_memory_info *info, *tmp;
>> +	int result;
>> +	int node;
>>
>>   	if (!device || !acpi_driver_data(device))
>>   		return -EINVAL;
>>
>>   	mem_device = acpi_driver_data(device);
>> +
>> +	node = acpi_get_node(mem_device->device->handle);
>> +
>> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
>> +		if (!info->enabled)
>> +			continue;
>> +
>> +		if (!is_memblk_offline(info->start_addr, info->length)) {
>> +			result = offline_memory(info->start_addr, info->length);
>> +			if (result)
>> +				return result;
>> +		}
>> +
>> +		result = remove_memory(node, info->start_addr, info->length);
>> +		if (result)
>> +			return result;
>> +
>> +		list_del(&info->list);
>> +		kfree(info);
>> +	}
>> +
>>   	kfree(mem_device);
> 
> The caller does not care the return value, and after this function returns, the
> memory device will be unbound from this driver, so we should free all memory
> allocated for driver data.

We can ignore return value of remove_memory() because I think that it should
return 0. But we cannot ignore return value of offline_memory() because
kernel panic will occurs if kernel removes online memory. How do we deal with
online memory?

>>
>>   	return 0;
>> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
>> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
>> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>>   extern int mem_online_node(int nid);
>>   extern int add_memory(int nid, u64 start, u64 size);
>>   extern int arch_add_memory(int nid, u64 start, u64 size);
>> +extern int remove_memory(int nid, u64 start, u64 size);
>>   extern int offline_memory(u64 start, u64 size);
>>   extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>>   								int nr_pages);
>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
>> @@ -659,6 +659,14 @@ out:
>>   }
>>   EXPORT_SYMBOL_GPL(add_memory);
>>
>> +int remove_memory(int nid, u64 start, u64 size)
>> +{
>> +	return -EBUSY;
>> +
>> +}
>> +EXPORT_SYMBOL_GPL(remove_memory);
>> +
>> +
>>   #ifdef CONFIG_MEMORY_HOTREMOVE
>>   /*
>>    * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
>> Index: linux-3.5-rc4/drivers/base/memory.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
>> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
>> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>>   }
>>   EXPORT_SYMBOL(unregister_memory_isolate_notifier);
>>
>> +bool is_memblk_offline(unsigned long start, unsigned long size)
>> +{
>> +	struct memory_block *mem = NULL;
>> +	struct mem_section *section;
>> +	unsigned long start_pfn, end_pfn;
>> +	unsigned long pfn, section_nr;
>> +
>> +	start_pfn = PFN_DOWN(start);
>> +	end_pfn = start_pfn + PFN_DOWN(start);
>> +
>> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
>> +		section_nr = pfn_to_section_nr(pfn);
>> +		if (!present_section_nr(section_nr));
>> +			continue;
>> +
>> +		section = __nr_to_section(section_nr);
>> +		/* same memblock? */
>> +		if (mem)
>> +			if((section_nr >= mem->start_section_nr) &&
>> +			   (section_nr <= mem->end_section_nr))
>> +				continue;
>> +
>> +		mem = find_memory_block_hinted(section, mem);
> 
> The second parameter should be NULL. Otherwise, the mem->dev.kobj will
> be put twice:
> 1. we put it when mem->state is MEM_OFFLINE
> 2. we put it in find_memory_block_hinted().

Ah, O.K.
How about it?

+bool is_memblk_offline(unsigned long start, unsigned long size)
+{
+	struct memory_block *mem = NULL;
+	struct mem_section *section;
+	unsigned long start_pfn, end_pfn;
+	unsigned long pfn, section_nr;
+
+	start_pfn = PFN_DOWN(start);
+	end_pfn = start_pfn + PFN_DOWN(start);
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		section_nr = pfn_to_section_nr(pfn);
+		if (!present_section_nr(section_nr));
+			continue;
+
+		section = __nr_to_section(section_nr);
+		/* same memblock? */
+		if (mem)
+			if((section_nr >= mem->start_section_nr) &&
+			   (section_nr <= mem->end_section_nr))
+				continue;
+
+		mem = find_memory_block_hinted(section, mem);
+		if (!mem)
+			continue;
+		if (mem->state == MEM_OFFLINE)
+			continue;
+
+		kobject_put(&mem->dev.kobj);
+		return false;
+	}
+
+	if (mem)
+		kobject_put(&mem->dev.kobj);
+
+	return true;
+}
+EXPORT_SYMBOL(is_memblk_offline);

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang
> 
>> +		if (!mem)
>> +			continue;
>> +		if (mem->state == MEM_OFFLINE) {
>> +			kobject_put(&mem->dev.kobj);
>> +			continue;
>> +		}
>> +
>> +		kobject_put(&mem->dev.kobj);
>> +		return false;
>> +	}
>> +
>> +	return true;
>> +}
>> +EXPORT_SYMBOL(is_memblk_offline);
>> +
>>   /*
>>    * register_memory - Setup a sysfs device for a memory block
>>    */
>> Index: linux-3.5-rc4/include/linux/memory.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
>> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
>> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>>   {
>>   	return 0;
>>   }
>> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
>> +{
>> +	return false;
>> +}
>>   #else
>>   extern int register_memory_notifier(struct notifier_block *nb);
>>   extern void unregister_memory_notifier(struct notifier_block *nb);
>> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>>   extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>>   							struct memory_block *);
>>   extern struct memory_block *find_memory_block(struct mem_section *);
>> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>>   #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>>   enum mem_add_context { BOOT, HOTPLUG };
>>   #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Wen Congyang]

At 07/03/2012 03:40 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/03 15:21, Wen Congyang wrote:
>> At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
>>> acpi_memory_device_remove() has been prepared to remove physical memory.
>>> But, the function only frees acpi_memory_device currentlry.
>>>
>>> The patch adds following functions into acpi_memory_device_remove():
>>>    - offline memory
>>>    - remove physical memory (only return -EBUSY)
>>>    - free acpi_memory_device
>>>
>>> CC: David Rientjes <rientjes@google.com>
>>> CC: Jiang Liu <liuj97@gmail.com>
>>> CC: Len Brown <len.brown@intel.com>
>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>> CC: Paul Mackerras <paulus@samba.org>
>>> CC: Christoph Lameter <cl@linux.com>
>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>
>>> ---
>>>   drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>>>   drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>>>   include/linux/memory.h         |    5 +++++
>>>   include/linux/memory_hotplug.h |    1 +
>>>   mm/memory_hotplug.c            |    8 ++++++++
>>>   5 files changed, 77 insertions(+), 1 deletion(-)
>>>
>>> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
>>> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
>>> @@ -29,6 +29,7 @@
>>>   #include <linux/module.h>
>>>   #include <linux/init.h>
>>>   #include <linux/types.h>
>>> +#include <linux/memory.h>
>>>   #include <linux/memory_hotplug.h>
>>>   #include <linux/slab.h>
>>>   #include <acpi/acpi_drivers.h>
>>> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>>>   static int acpi_memory_device_remove(struct acpi_device *device, int type)
>>>   {
>>>   	struct acpi_memory_device *mem_device = NULL;
>>> -
>>> +	struct acpi_memory_info *info, *tmp;
>>> +	int result;
>>> +	int node;
>>>
>>>   	if (!device || !acpi_driver_data(device))
>>>   		return -EINVAL;
>>>
>>>   	mem_device = acpi_driver_data(device);
>>> +
>>> +	node = acpi_get_node(mem_device->device->handle);
>>> +
>>> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
>>> +		if (!info->enabled)
>>> +			continue;
>>> +
>>> +		if (!is_memblk_offline(info->start_addr, info->length)) {
>>> +			result = offline_memory(info->start_addr, info->length);
>>> +			if (result)
>>> +				return result;
>>> +		}
>>> +
>>> +		result = remove_memory(node, info->start_addr, info->length);
>>> +		if (result)
>>> +			return result;
>>> +
>>> +		list_del(&info->list);
>>> +		kfree(info);
>>> +	}
>>> +
>>>   	kfree(mem_device);
>>
>> The caller does not care the return value, and after this function returns, the
>> memory device will be unbound from this driver, so we should free all memory
>> allocated for driver data.
> 
> We can ignore return value of remove_memory() because I think that it should
> return 0. But we cannot ignore return value of offline_memory() because
> kernel panic will occurs if kernel removes online memory. How do we deal with
> online memory?

Yes, We can not remove online memory, so just free the memory if offline_memory()
or remove_memory() fails.

> 
>>>
>>>   	return 0;
>>> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
>>> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
>>> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>>>   extern int mem_online_node(int nid);
>>>   extern int add_memory(int nid, u64 start, u64 size);
>>>   extern int arch_add_memory(int nid, u64 start, u64 size);
>>> +extern int remove_memory(int nid, u64 start, u64 size);
>>>   extern int offline_memory(u64 start, u64 size);
>>>   extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>>>   								int nr_pages);
>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
>>> @@ -659,6 +659,14 @@ out:
>>>   }
>>>   EXPORT_SYMBOL_GPL(add_memory);
>>>
>>> +int remove_memory(int nid, u64 start, u64 size)
>>> +{
>>> +	return -EBUSY;
>>> +
>>> +}
>>> +EXPORT_SYMBOL_GPL(remove_memory);
>>> +
>>> +
>>>   #ifdef CONFIG_MEMORY_HOTREMOVE
>>>   /*
>>>    * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
>>> Index: linux-3.5-rc4/drivers/base/memory.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
>>> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
>>> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>>>   }
>>>   EXPORT_SYMBOL(unregister_memory_isolate_notifier);
>>>
>>> +bool is_memblk_offline(unsigned long start, unsigned long size)
>>> +{
>>> +	struct memory_block *mem = NULL;
>>> +	struct mem_section *section;
>>> +	unsigned long start_pfn, end_pfn;
>>> +	unsigned long pfn, section_nr;
>>> +
>>> +	start_pfn = PFN_DOWN(start);
>>> +	end_pfn = start_pfn + PFN_DOWN(start);
>>> +
>>> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
>>> +		section_nr = pfn_to_section_nr(pfn);
>>> +		if (!present_section_nr(section_nr));
>>> +			continue;
>>> +
>>> +		section = __nr_to_section(section_nr);
>>> +		/* same memblock? */
>>> +		if (mem)
>>> +			if((section_nr >= mem->start_section_nr) &&
>>> +			   (section_nr <= mem->end_section_nr))
>>> +				continue;
>>> +
>>> +		mem = find_memory_block_hinted(section, mem);
>>
>> The second parameter should be NULL. Otherwise, the mem->dev.kobj will
>> be put twice:
>> 1. we put it when mem->state is MEM_OFFLINE
>> 2. we put it in find_memory_block_hinted().
> 
> Ah, O.K.
> How about it?

This version looks fine to me.

Thanks
Wen Congyang

> 
> +bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	struct memory_block *mem = NULL;
> +	struct mem_section *section;
> +	unsigned long start_pfn, end_pfn;
> +	unsigned long pfn, section_nr;
> +
> +	start_pfn = PFN_DOWN(start);
> +	end_pfn = start_pfn + PFN_DOWN(start);
> +
> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
> +		section_nr = pfn_to_section_nr(pfn);
> +		if (!present_section_nr(section_nr));
> +			continue;
> +
> +		section = __nr_to_section(section_nr);
> +		/* same memblock? */
> +		if (mem)
> +			if((section_nr >= mem->start_section_nr) &&
> +			   (section_nr <= mem->end_section_nr))
> +				continue;
> +
> +		mem = find_memory_block_hinted(section, mem);
> +		if (!mem)
> +			continue;
> +		if (mem->state == MEM_OFFLINE)
> +			continue;
> +
> +		kobject_put(&mem->dev.kobj);
> +		return false;
> +	}
> +
> +	if (mem)
> +		kobject_put(&mem->dev.kobj);
> +
> +	return true;
> +}
> +EXPORT_SYMBOL(is_memblk_offline);
> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang
>>
>>> +		if (!mem)
>>> +			continue;
>>> +		if (mem->state == MEM_OFFLINE) {
>>> +			kobject_put(&mem->dev.kobj);
>>> +			continue;
>>> +		}
>>> +
>>> +		kobject_put(&mem->dev.kobj);
>>> +		return false;
>>> +	}
>>> +
>>> +	return true;
>>> +}
>>> +EXPORT_SYMBOL(is_memblk_offline);
>>> +
>>>   /*
>>>    * register_memory - Setup a sysfs device for a memory block
>>>    */
>>> Index: linux-3.5-rc4/include/linux/memory.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
>>> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
>>> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>>>   {
>>>   	return 0;
>>>   }
>>> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
>>> +{
>>> +	return false;
>>> +}
>>>   #else
>>>   extern int register_memory_notifier(struct notifier_block *nb);
>>>   extern void unregister_memory_notifier(struct notifier_block *nb);
>>> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>>>   extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>>>   							struct memory_block *);
>>>   extern struct memory_block *find_memory_block(struct mem_section *);
>>> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>>>   #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>>>   enum mem_add_context { BOOT, HOTPLUG };
>>>   #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
> 
> 
> 
> 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Wen Congyang]

At 07/03/2012 03:40 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/03 15:21, Wen Congyang wrote:
>> At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
>>> acpi_memory_device_remove() has been prepared to remove physical memory.
>>> But, the function only frees acpi_memory_device currentlry.
>>>
>>> The patch adds following functions into acpi_memory_device_remove():
>>>    - offline memory
>>>    - remove physical memory (only return -EBUSY)
>>>    - free acpi_memory_device
>>>
>>> CC: David Rientjes <rientjes@google.com>
>>> CC: Jiang Liu <liuj97@gmail.com>
>>> CC: Len Brown <len.brown@intel.com>
>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>> CC: Paul Mackerras <paulus@samba.org>
>>> CC: Christoph Lameter <cl@linux.com>
>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>
>>> ---
>>>   drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>>>   drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>>>   include/linux/memory.h         |    5 +++++
>>>   include/linux/memory_hotplug.h |    1 +
>>>   mm/memory_hotplug.c            |    8 ++++++++
>>>   5 files changed, 77 insertions(+), 1 deletion(-)
>>>
>>> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
>>> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
>>> @@ -29,6 +29,7 @@
>>>   #include <linux/module.h>
>>>   #include <linux/init.h>
>>>   #include <linux/types.h>
>>> +#include <linux/memory.h>
>>>   #include <linux/memory_hotplug.h>
>>>   #include <linux/slab.h>
>>>   #include <acpi/acpi_drivers.h>
>>> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>>>   static int acpi_memory_device_remove(struct acpi_device *device, int type)
>>>   {
>>>   	struct acpi_memory_device *mem_device = NULL;
>>> -
>>> +	struct acpi_memory_info *info, *tmp;
>>> +	int result;
>>> +	int node;
>>>
>>>   	if (!device || !acpi_driver_data(device))
>>>   		return -EINVAL;
>>>
>>>   	mem_device = acpi_driver_data(device);
>>> +
>>> +	node = acpi_get_node(mem_device->device->handle);
>>> +
>>> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
>>> +		if (!info->enabled)
>>> +			continue;
>>> +
>>> +		if (!is_memblk_offline(info->start_addr, info->length)) {
>>> +			result = offline_memory(info->start_addr, info->length);
>>> +			if (result)
>>> +				return result;
>>> +		}
>>> +
>>> +		result = remove_memory(node, info->start_addr, info->length);
>>> +		if (result)
>>> +			return result;
>>> +
>>> +		list_del(&info->list);
>>> +		kfree(info);
>>> +	}
>>> +
>>>   	kfree(mem_device);
>>
>> The caller does not care the return value, and after this function returns, the
>> memory device will be unbound from this driver, so we should free all memory
>> allocated for driver data.
> 
> We can ignore return value of remove_memory() because I think that it should
> return 0. But we cannot ignore return value of offline_memory() because
> kernel panic will occurs if kernel removes online memory. How do we deal with
> online memory?

Yes, We can not remove online memory, so just free the memory if offline_memory()
or remove_memory() fails.

> 
>>>
>>>   	return 0;
>>> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
>>> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
>>> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>>>   extern int mem_online_node(int nid);
>>>   extern int add_memory(int nid, u64 start, u64 size);
>>>   extern int arch_add_memory(int nid, u64 start, u64 size);
>>> +extern int remove_memory(int nid, u64 start, u64 size);
>>>   extern int offline_memory(u64 start, u64 size);
>>>   extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>>>   								int nr_pages);
>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
>>> @@ -659,6 +659,14 @@ out:
>>>   }
>>>   EXPORT_SYMBOL_GPL(add_memory);
>>>
>>> +int remove_memory(int nid, u64 start, u64 size)
>>> +{
>>> +	return -EBUSY;
>>> +
>>> +}
>>> +EXPORT_SYMBOL_GPL(remove_memory);
>>> +
>>> +
>>>   #ifdef CONFIG_MEMORY_HOTREMOVE
>>>   /*
>>>    * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
>>> Index: linux-3.5-rc4/drivers/base/memory.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
>>> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
>>> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>>>   }
>>>   EXPORT_SYMBOL(unregister_memory_isolate_notifier);
>>>
>>> +bool is_memblk_offline(unsigned long start, unsigned long size)
>>> +{
>>> +	struct memory_block *mem = NULL;
>>> +	struct mem_section *section;
>>> +	unsigned long start_pfn, end_pfn;
>>> +	unsigned long pfn, section_nr;
>>> +
>>> +	start_pfn = PFN_DOWN(start);
>>> +	end_pfn = start_pfn + PFN_DOWN(start);
>>> +
>>> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
>>> +		section_nr = pfn_to_section_nr(pfn);
>>> +		if (!present_section_nr(section_nr));
>>> +			continue;
>>> +
>>> +		section = __nr_to_section(section_nr);
>>> +		/* same memblock? */
>>> +		if (mem)
>>> +			if((section_nr >= mem->start_section_nr) &&
>>> +			   (section_nr <= mem->end_section_nr))
>>> +				continue;
>>> +
>>> +		mem = find_memory_block_hinted(section, mem);
>>
>> The second parameter should be NULL. Otherwise, the mem->dev.kobj will
>> be put twice:
>> 1. we put it when mem->state is MEM_OFFLINE
>> 2. we put it in find_memory_block_hinted().
> 
> Ah, O.K.
> How about it?

This version looks fine to me.

Thanks
Wen Congyang

> 
> +bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	struct memory_block *mem = NULL;
> +	struct mem_section *section;
> +	unsigned long start_pfn, end_pfn;
> +	unsigned long pfn, section_nr;
> +
> +	start_pfn = PFN_DOWN(start);
> +	end_pfn = start_pfn + PFN_DOWN(start);
> +
> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
> +		section_nr = pfn_to_section_nr(pfn);
> +		if (!present_section_nr(section_nr));
> +			continue;
> +
> +		section = __nr_to_section(section_nr);
> +		/* same memblock? */
> +		if (mem)
> +			if((section_nr >= mem->start_section_nr) &&
> +			   (section_nr <= mem->end_section_nr))
> +				continue;
> +
> +		mem = find_memory_block_hinted(section, mem);
> +		if (!mem)
> +			continue;
> +		if (mem->state == MEM_OFFLINE)
> +			continue;
> +
> +		kobject_put(&mem->dev.kobj);
> +		return false;
> +	}
> +
> +	if (mem)
> +		kobject_put(&mem->dev.kobj);
> +
> +	return true;
> +}
> +EXPORT_SYMBOL(is_memblk_offline);
> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang
>>
>>> +		if (!mem)
>>> +			continue;
>>> +		if (mem->state == MEM_OFFLINE) {
>>> +			kobject_put(&mem->dev.kobj);
>>> +			continue;
>>> +		}
>>> +
>>> +		kobject_put(&mem->dev.kobj);
>>> +		return false;
>>> +	}
>>> +
>>> +	return true;
>>> +}
>>> +EXPORT_SYMBOL(is_memblk_offline);
>>> +
>>>   /*
>>>    * register_memory - Setup a sysfs device for a memory block
>>>    */
>>> Index: linux-3.5-rc4/include/linux/memory.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
>>> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
>>> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>>>   {
>>>   	return 0;
>>>   }
>>> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
>>> +{
>>> +	return false;
>>> +}
>>>   #else
>>>   extern int register_memory_notifier(struct notifier_block *nb);
>>>   extern void unregister_memory_notifier(struct notifier_block *nb);
>>> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>>>   extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>>>   							struct memory_block *);
>>>   extern struct memory_block *find_memory_block(struct mem_section *);
>>> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>>>   #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>>>   enum mem_add_context { BOOT, HOTPLUG };
>>>   #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
> 
> 
> 
> 

Re: [RFC PATCH v2 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove

[Wen Congyang]

At 07/03/2012 03:40 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/03 15:21, Wen Congyang wrote:
>> At 07/03/2012 01:54 PM, Yasuaki Ishimatsu Wrote:
>>> acpi_memory_device_remove() has been prepared to remove physical memory.
>>> But, the function only frees acpi_memory_device currentlry.
>>>
>>> The patch adds following functions into acpi_memory_device_remove():
>>>    - offline memory
>>>    - remove physical memory (only return -EBUSY)
>>>    - free acpi_memory_device
>>>
>>> CC: David Rientjes <rientjes@google.com>
>>> CC: Jiang Liu <liuj97@gmail.com>
>>> CC: Len Brown <len.brown@intel.com>
>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>> CC: Paul Mackerras <paulus@samba.org>
>>> CC: Christoph Lameter <cl@linux.com>
>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>
>>> ---
>>>   drivers/acpi/acpi_memhotplug.c |   26 +++++++++++++++++++++++++-
>>>   drivers/base/memory.c          |   38 ++++++++++++++++++++++++++++++++++++++
>>>   include/linux/memory.h         |    5 +++++
>>>   include/linux/memory_hotplug.h |    1 +
>>>   mm/memory_hotplug.c            |    8 ++++++++
>>>   5 files changed, 77 insertions(+), 1 deletion(-)
>>>
>>> Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:49.458374960 +0900
>>> +++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c	2012-07-03 14:21:58.329264059 +0900
>>> @@ -29,6 +29,7 @@
>>>   #include <linux/module.h>
>>>   #include <linux/init.h>
>>>   #include <linux/types.h>
>>> +#include <linux/memory.h>
>>>   #include <linux/memory_hotplug.h>
>>>   #include <linux/slab.h>
>>>   #include <acpi/acpi_drivers.h>
>>> @@ -452,12 +453,35 @@ static int acpi_memory_device_add(struct
>>>   static int acpi_memory_device_remove(struct acpi_device *device, int type)
>>>   {
>>>   	struct acpi_memory_device *mem_device = NULL;
>>> -
>>> +	struct acpi_memory_info *info, *tmp;
>>> +	int result;
>>> +	int node;
>>>
>>>   	if (!device || !acpi_driver_data(device))
>>>   		return -EINVAL;
>>>
>>>   	mem_device = acpi_driver_data(device);
>>> +
>>> +	node = acpi_get_node(mem_device->device->handle);
>>> +
>>> +	list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
>>> +		if (!info->enabled)
>>> +			continue;
>>> +
>>> +		if (!is_memblk_offline(info->start_addr, info->length)) {
>>> +			result = offline_memory(info->start_addr, info->length);
>>> +			if (result)
>>> +				return result;
>>> +		}
>>> +
>>> +		result = remove_memory(node, info->start_addr, info->length);
>>> +		if (result)
>>> +			return result;
>>> +
>>> +		list_del(&info->list);
>>> +		kfree(info);
>>> +	}
>>> +
>>>   	kfree(mem_device);
>>
>> The caller does not care the return value, and after this function returns, the
>> memory device will be unbound from this driver, so we should free all memory
>> allocated for driver data.
> 
> We can ignore return value of remove_memory() because I think that it should
> return 0. But we cannot ignore return value of offline_memory() because
> kernel panic will occurs if kernel removes online memory. How do we deal with
> online memory?

Yes, We can not remove online memory, so just free the memory if offline_memory()
or remove_memory() fails.

> 
>>>
>>>   	return 0;
>>> Index: linux-3.5-rc4/include/linux/memory_hotplug.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/memory_hotplug.h	2012-07-03 14:21:49.471374796 +0900
>>> +++ linux-3.5-rc4/include/linux/memory_hotplug.h	2012-07-03 14:21:58.330264047 +0900
>>> @@ -233,6 +233,7 @@ static inline int is_mem_section_removab
>>>   extern int mem_online_node(int nid);
>>>   extern int add_memory(int nid, u64 start, u64 size);
>>>   extern int arch_add_memory(int nid, u64 start, u64 size);
>>> +extern int remove_memory(int nid, u64 start, u64 size);
>>>   extern int offline_memory(u64 start, u64 size);
>>>   extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
>>>   								int nr_pages);
>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:21:49.466374860 +0900
>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:21:58.332264022 +0900
>>> @@ -659,6 +659,14 @@ out:
>>>   }
>>>   EXPORT_SYMBOL_GPL(add_memory);
>>>
>>> +int remove_memory(int nid, u64 start, u64 size)
>>> +{
>>> +	return -EBUSY;
>>> +
>>> +}
>>> +EXPORT_SYMBOL_GPL(remove_memory);
>>> +
>>> +
>>>   #ifdef CONFIG_MEMORY_HOTREMOVE
>>>   /*
>>>    * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
>>> Index: linux-3.5-rc4/drivers/base/memory.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/base/memory.c	2012-07-03 14:21:49.459374948 +0900
>>> +++ linux-3.5-rc4/drivers/base/memory.c	2012-07-03 14:21:58.335263984 +0900
>>> @@ -70,6 +70,44 @@ void unregister_memory_isolate_notifier(
>>>   }
>>>   EXPORT_SYMBOL(unregister_memory_isolate_notifier);
>>>
>>> +bool is_memblk_offline(unsigned long start, unsigned long size)
>>> +{
>>> +	struct memory_block *mem = NULL;
>>> +	struct mem_section *section;
>>> +	unsigned long start_pfn, end_pfn;
>>> +	unsigned long pfn, section_nr;
>>> +
>>> +	start_pfn = PFN_DOWN(start);
>>> +	end_pfn = start_pfn + PFN_DOWN(start);
>>> +
>>> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
>>> +		section_nr = pfn_to_section_nr(pfn);
>>> +		if (!present_section_nr(section_nr));
>>> +			continue;
>>> +
>>> +		section = __nr_to_section(section_nr);
>>> +		/* same memblock? */
>>> +		if (mem)
>>> +			if((section_nr >= mem->start_section_nr) &&
>>> +			   (section_nr <= mem->end_section_nr))
>>> +				continue;
>>> +
>>> +		mem = find_memory_block_hinted(section, mem);
>>
>> The second parameter should be NULL. Otherwise, the mem->dev.kobj will
>> be put twice:
>> 1. we put it when mem->state is MEM_OFFLINE
>> 2. we put it in find_memory_block_hinted().
> 
> Ah, O.K.
> How about it?

This version looks fine to me.

Thanks
Wen Congyang

> 
> +bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +	struct memory_block *mem = NULL;
> +	struct mem_section *section;
> +	unsigned long start_pfn, end_pfn;
> +	unsigned long pfn, section_nr;
> +
> +	start_pfn = PFN_DOWN(start);
> +	end_pfn = start_pfn + PFN_DOWN(start);
> +
> +	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
> +		section_nr = pfn_to_section_nr(pfn);
> +		if (!present_section_nr(section_nr));
> +			continue;
> +
> +		section = __nr_to_section(section_nr);
> +		/* same memblock? */
> +		if (mem)
> +			if((section_nr >= mem->start_section_nr) &&
> +			   (section_nr <= mem->end_section_nr))
> +				continue;
> +
> +		mem = find_memory_block_hinted(section, mem);
> +		if (!mem)
> +			continue;
> +		if (mem->state == MEM_OFFLINE)
> +			continue;
> +
> +		kobject_put(&mem->dev.kobj);
> +		return false;
> +	}
> +
> +	if (mem)
> +		kobject_put(&mem->dev.kobj);
> +
> +	return true;
> +}
> +EXPORT_SYMBOL(is_memblk_offline);
> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang
>>
>>> +		if (!mem)
>>> +			continue;
>>> +		if (mem->state == MEM_OFFLINE) {
>>> +			kobject_put(&mem->dev.kobj);
>>> +			continue;
>>> +		}
>>> +
>>> +		kobject_put(&mem->dev.kobj);
>>> +		return false;
>>> +	}
>>> +
>>> +	return true;
>>> +}
>>> +EXPORT_SYMBOL(is_memblk_offline);
>>> +
>>>   /*
>>>    * register_memory - Setup a sysfs device for a memory block
>>>    */
>>> Index: linux-3.5-rc4/include/linux/memory.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/memory.h	2012-07-03 14:21:45.998418215 +0900
>>> +++ linux-3.5-rc4/include/linux/memory.h	2012-07-03 14:21:58.340263922 +0900
>>> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>>>   {
>>>   	return 0;
>>>   }
>>> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
>>> +{
>>> +	return false;
>>> +}
>>>   #else
>>>   extern int register_memory_notifier(struct notifier_block *nb);
>>>   extern void unregister_memory_notifier(struct notifier_block *nb);
>>> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>>>   extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>>>   							struct memory_block *);
>>>   extern struct memory_block *find_memory_block(struct mem_section *);
>>> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>>>   #define CONFIG_MEM_BLOCK_SIZE	(PAGES_PER_SECTION<<PAGE_SHIFT)
>>>   enum mem_add_context { BOOT, HOTPLUG };
>>>   #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
> 
> 
> 
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/03 15:35, Wen Congyang wrote:
> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>> sysfs files are created. But there is no code to remove these files. The patch
>> implements the function to remove them.
>>
>> Note : The code does not free firmware_map_entry since there is no way to free
>>         memory which is allocated by bootmem.
>>
>> CC: David Rientjes <rientjes@google.com>
>> CC: Jiang Liu <liuj97@gmail.com>
>> CC: Len Brown <len.brown@intel.com>
>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> CC: Paul Mackerras <paulus@samba.org>
>> CC: Christoph Lameter <cl@linux.com>
>> Cc: Minchan Kim <minchan.kim@gmail.com>
>> CC: Andrew Morton <akpm@linux-foundation.org>
>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>
>> ---
>>   drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>   include/linux/firmware-map.h |    6 +++
>>   mm/memory_hotplug.c          |    6 +++
>>   3 files changed, 81 insertions(+), 1 deletion(-)
>>
>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>
>>   int remove_memory(int nid, u64 start, u64 size)
>>   {
>> -	return -EBUSY;
>> +	lock_memory_hotplug();
>> +	/* remove memmap entry */
>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>> +	unlock_memory_hotplug();
>> +	return 0;
>>
>>   }
>>   EXPORT_SYMBOL_GPL(remove_memory);
>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>> @@ -25,6 +25,7 @@
>>
>>   int firmware_map_add_early(u64 start, u64 end, const char *type);
>>   int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>
>>   #else /* CONFIG_FIRMWARE_MEMMAP */
>>
>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>   	return 0;
>>   }
>>
>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>> +{
>> +	return 0;
>> +}
>> +
>>   #endif /* CONFIG_FIRMWARE_MEMMAP */
>>
>>   #endif /* _LINUX_FIRMWARE_MAP_H */
>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>   	.show = memmap_attr_show,
>>   };
>>
>> +static void release_firmware_map_entry(struct kobject *kobj)
>> +{
>> +	/*
>> +	 * FIXME : There is no idea.
>> +	 *         How to free the entry which allocated bootmem?
>> +	 */
> 
> I find a function free_bootmem(), but I am not sure whether it can work here.

It cannot work here.

> Another problem: how to check whether the entry uses bootmem?

When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
So we can check whether the entry was allocated by bootmem or not.
If the eantry was allocated by kzalloc(), we can free the entry by kfree().
But if the entry was allocated by bootmem, we have no way to free the entry.

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang
> 
>> +}
>> +
>>   static struct kobj_type memmap_ktype = {
>> +	.release	= release_firmware_map_entry,
>>   	.sysfs_ops	= &memmap_attr_ops,
>>   	.default_attrs	= def_attrs,
>>   };
>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>   	return 0;
>>   }
>>
>> +/**
>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>> + * memmap entry.
>> + * @entry: removed entry.
>> + **/
>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>> +{
>> +	list_del(&entry->list);
>> +}
>> +
>>   /*
>>    * Add memmap entry on sysfs
>>    */
>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>   	return 0;
>>   }
>>
>> +/*
>> + * Remove memmap entry on sysfs
>> + */
>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>> +{
>> +	kobject_put(&entry->kobj);
>> +}
>> +
>> +/*
>> + * Search memmap entry
>> + */
>> +
>> +struct firmware_map_entry * __meminit
>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>> +{
>> +	struct firmware_map_entry *entry;
>> +
>> +	list_for_each_entry(entry, &map_entries, list)
>> +		if ((entry->start == start) && (entry->end == end) &&
>> +		    (!strcmp(entry->type, type)))
>> +			return entry;
>> +
>> +	return NULL;
>> +}
>> +
>>   /**
>>    * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>    * memory hotplug.
>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>   	return firmware_map_add_entry(start, end, type, entry);
>>   }
>>
>> +/**
>> + * firmware_map_remove() - remove a firmware mapping entry
>> + * @start: Start of the memory range.
>> + * @end:   End of the memory range (inclusive).
>> + * @type:  Type of the memory range.
>> + *
>> + * removes a firmware mapping entry.
>> + *
>> + * Returns 0 on success, or -EINVAL if no entry.
>> + **/
>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>> +{
>> +	struct firmware_map_entry *entry;
>> +
>> +	entry = find_firmware_map_entry(start, end, type);
>> +	if (!entry)
>> +		return -EINVAL;
>> +
>> +	/* remove the memmap entry */
>> +	remove_sysfs_fw_map_entry(entry);
>> +
>> +	firmware_map_remove_entry(entry);
>> +
>> +	return 0;
>> +}
>> +
>>   /*
>>    * Sysfs functions -------------------------------------------------------------
>>    */
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 



--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/03 15:35, Wen Congyang wrote:
> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>> sysfs files are created. But there is no code to remove these files. The patch
>> implements the function to remove them.
>>
>> Note : The code does not free firmware_map_entry since there is no way to free
>>         memory which is allocated by bootmem.
>>
>> CC: David Rientjes <rientjes@google.com>
>> CC: Jiang Liu <liuj97@gmail.com>
>> CC: Len Brown <len.brown@intel.com>
>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> CC: Paul Mackerras <paulus@samba.org>
>> CC: Christoph Lameter <cl@linux.com>
>> Cc: Minchan Kim <minchan.kim@gmail.com>
>> CC: Andrew Morton <akpm@linux-foundation.org>
>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>
>> ---
>>   drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>   include/linux/firmware-map.h |    6 +++
>>   mm/memory_hotplug.c          |    6 +++
>>   3 files changed, 81 insertions(+), 1 deletion(-)
>>
>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>
>>   int remove_memory(int nid, u64 start, u64 size)
>>   {
>> -	return -EBUSY;
>> +	lock_memory_hotplug();
>> +	/* remove memmap entry */
>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>> +	unlock_memory_hotplug();
>> +	return 0;
>>
>>   }
>>   EXPORT_SYMBOL_GPL(remove_memory);
>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>> @@ -25,6 +25,7 @@
>>
>>   int firmware_map_add_early(u64 start, u64 end, const char *type);
>>   int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>
>>   #else /* CONFIG_FIRMWARE_MEMMAP */
>>
>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>   	return 0;
>>   }
>>
>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>> +{
>> +	return 0;
>> +}
>> +
>>   #endif /* CONFIG_FIRMWARE_MEMMAP */
>>
>>   #endif /* _LINUX_FIRMWARE_MAP_H */
>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>   	.show = memmap_attr_show,
>>   };
>>
>> +static void release_firmware_map_entry(struct kobject *kobj)
>> +{
>> +	/*
>> +	 * FIXME : There is no idea.
>> +	 *         How to free the entry which allocated bootmem?
>> +	 */
> 
> I find a function free_bootmem(), but I am not sure whether it can work here.

It cannot work here.

> Another problem: how to check whether the entry uses bootmem?

When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
So we can check whether the entry was allocated by bootmem or not.
If the eantry was allocated by kzalloc(), we can free the entry by kfree().
But if the entry was allocated by bootmem, we have no way to free the entry.

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang
> 
>> +}
>> +
>>   static struct kobj_type memmap_ktype = {
>> +	.release	= release_firmware_map_entry,
>>   	.sysfs_ops	= &memmap_attr_ops,
>>   	.default_attrs	= def_attrs,
>>   };
>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>   	return 0;
>>   }
>>
>> +/**
>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>> + * memmap entry.
>> + * @entry: removed entry.
>> + **/
>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>> +{
>> +	list_del(&entry->list);
>> +}
>> +
>>   /*
>>    * Add memmap entry on sysfs
>>    */
>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>   	return 0;
>>   }
>>
>> +/*
>> + * Remove memmap entry on sysfs
>> + */
>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>> +{
>> +	kobject_put(&entry->kobj);
>> +}
>> +
>> +/*
>> + * Search memmap entry
>> + */
>> +
>> +struct firmware_map_entry * __meminit
>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>> +{
>> +	struct firmware_map_entry *entry;
>> +
>> +	list_for_each_entry(entry, &map_entries, list)
>> +		if ((entry->start == start) && (entry->end == end) &&
>> +		    (!strcmp(entry->type, type)))
>> +			return entry;
>> +
>> +	return NULL;
>> +}
>> +
>>   /**
>>    * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>    * memory hotplug.
>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>   	return firmware_map_add_entry(start, end, type, entry);
>>   }
>>
>> +/**
>> + * firmware_map_remove() - remove a firmware mapping entry
>> + * @start: Start of the memory range.
>> + * @end:   End of the memory range (inclusive).
>> + * @type:  Type of the memory range.
>> + *
>> + * removes a firmware mapping entry.
>> + *
>> + * Returns 0 on success, or -EINVAL if no entry.
>> + **/
>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>> +{
>> +	struct firmware_map_entry *entry;
>> +
>> +	entry = find_firmware_map_entry(start, end, type);
>> +	if (!entry)
>> +		return -EINVAL;
>> +
>> +	/* remove the memmap entry */
>> +	remove_sysfs_fw_map_entry(entry);
>> +
>> +	firmware_map_remove_entry(entry);
>> +
>> +	return 0;
>> +}
>> +
>>   /*
>>    * Sysfs functions -------------------------------------------------------------
>>    */
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/03 15:35, Wen Congyang wrote:
> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>> sysfs files are created. But there is no code to remove these files. The patch
>> implements the function to remove them.
>>
>> Note : The code does not free firmware_map_entry since there is no way to free
>>         memory which is allocated by bootmem.
>>
>> CC: David Rientjes <rientjes@google.com>
>> CC: Jiang Liu <liuj97@gmail.com>
>> CC: Len Brown <len.brown@intel.com>
>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> CC: Paul Mackerras <paulus@samba.org>
>> CC: Christoph Lameter <cl@linux.com>
>> Cc: Minchan Kim <minchan.kim@gmail.com>
>> CC: Andrew Morton <akpm@linux-foundation.org>
>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>
>> ---
>>   drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>   include/linux/firmware-map.h |    6 +++
>>   mm/memory_hotplug.c          |    6 +++
>>   3 files changed, 81 insertions(+), 1 deletion(-)
>>
>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>
>>   int remove_memory(int nid, u64 start, u64 size)
>>   {
>> -	return -EBUSY;
>> +	lock_memory_hotplug();
>> +	/* remove memmap entry */
>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>> +	unlock_memory_hotplug();
>> +	return 0;
>>
>>   }
>>   EXPORT_SYMBOL_GPL(remove_memory);
>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>> ===================================================================
>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>> @@ -25,6 +25,7 @@
>>
>>   int firmware_map_add_early(u64 start, u64 end, const char *type);
>>   int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>
>>   #else /* CONFIG_FIRMWARE_MEMMAP */
>>
>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>   	return 0;
>>   }
>>
>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>> +{
>> +	return 0;
>> +}
>> +
>>   #endif /* CONFIG_FIRMWARE_MEMMAP */
>>
>>   #endif /* _LINUX_FIRMWARE_MAP_H */
>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>> ===================================================================
>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>   	.show = memmap_attr_show,
>>   };
>>
>> +static void release_firmware_map_entry(struct kobject *kobj)
>> +{
>> +	/*
>> +	 * FIXME : There is no idea.
>> +	 *         How to free the entry which allocated bootmem?
>> +	 */
> 
> I find a function free_bootmem(), but I am not sure whether it can work here.

It cannot work here.

> Another problem: how to check whether the entry uses bootmem?

When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
So we can check whether the entry was allocated by bootmem or not.
If the eantry was allocated by kzalloc(), we can free the entry by kfree().
But if the entry was allocated by bootmem, we have no way to free the entry.

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang
> 
>> +}
>> +
>>   static struct kobj_type memmap_ktype = {
>> +	.release	= release_firmware_map_entry,
>>   	.sysfs_ops	= &memmap_attr_ops,
>>   	.default_attrs	= def_attrs,
>>   };
>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>   	return 0;
>>   }
>>
>> +/**
>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>> + * memmap entry.
>> + * @entry: removed entry.
>> + **/
>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>> +{
>> +	list_del(&entry->list);
>> +}
>> +
>>   /*
>>    * Add memmap entry on sysfs
>>    */
>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>   	return 0;
>>   }
>>
>> +/*
>> + * Remove memmap entry on sysfs
>> + */
>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>> +{
>> +	kobject_put(&entry->kobj);
>> +}
>> +
>> +/*
>> + * Search memmap entry
>> + */
>> +
>> +struct firmware_map_entry * __meminit
>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>> +{
>> +	struct firmware_map_entry *entry;
>> +
>> +	list_for_each_entry(entry, &map_entries, list)
>> +		if ((entry->start == start) && (entry->end == end) &&
>> +		    (!strcmp(entry->type, type)))
>> +			return entry;
>> +
>> +	return NULL;
>> +}
>> +
>>   /**
>>    * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>    * memory hotplug.
>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>   	return firmware_map_add_entry(start, end, type, entry);
>>   }
>>
>> +/**
>> + * firmware_map_remove() - remove a firmware mapping entry
>> + * @start: Start of the memory range.
>> + * @end:   End of the memory range (inclusive).
>> + * @type:  Type of the memory range.
>> + *
>> + * removes a firmware mapping entry.
>> + *
>> + * Returns 0 on success, or -EINVAL if no entry.
>> + **/
>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>> +{
>> +	struct firmware_map_entry *entry;
>> +
>> +	entry = find_firmware_map_entry(start, end, type);
>> +	if (!entry)
>> +		return -EINVAL;
>> +
>> +	/* remove the memmap entry */
>> +	remove_sysfs_fw_map_entry(entry);
>> +
>> +	firmware_map_remove_entry(entry);
>> +
>> +	return 0;
>> +}
>> +
>>   /*
>>    * Sysfs functions -------------------------------------------------------------
>>    */
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/03 15:35, Wen Congyang wrote:
>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>> sysfs files are created. But there is no code to remove these files. The patch
>>> implements the function to remove them.
>>>
>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>         memory which is allocated by bootmem.
>>>
>>> CC: David Rientjes <rientjes@google.com>
>>> CC: Jiang Liu <liuj97@gmail.com>
>>> CC: Len Brown <len.brown@intel.com>
>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>> CC: Paul Mackerras <paulus@samba.org>
>>> CC: Christoph Lameter <cl@linux.com>
>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>
>>> ---
>>>   drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>   include/linux/firmware-map.h |    6 +++
>>>   mm/memory_hotplug.c          |    6 +++
>>>   3 files changed, 81 insertions(+), 1 deletion(-)
>>>
>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>
>>>   int remove_memory(int nid, u64 start, u64 size)
>>>   {
>>> -	return -EBUSY;
>>> +	lock_memory_hotplug();
>>> +	/* remove memmap entry */
>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>> +	unlock_memory_hotplug();
>>> +	return 0;
>>>
>>>   }
>>>   EXPORT_SYMBOL_GPL(remove_memory);
>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>> @@ -25,6 +25,7 @@
>>>
>>>   int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>   int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>
>>>   #else /* CONFIG_FIRMWARE_MEMMAP */
>>>
>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>   	return 0;
>>>   }
>>>
>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>> +{
>>> +	return 0;
>>> +}
>>> +
>>>   #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>
>>>   #endif /* _LINUX_FIRMWARE_MAP_H */
>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>   	.show = memmap_attr_show,
>>>   };
>>>
>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>> +{
>>> +	/*
>>> +	 * FIXME : There is no idea.
>>> +	 *         How to free the entry which allocated bootmem?
>>> +	 */
>>
>> I find a function free_bootmem(), but I am not sure whether it can work here.
> 
> It cannot work here.
> 
>> Another problem: how to check whether the entry uses bootmem?
> 
> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.

This is not true. In my test, I find the page does not have PG_slab sometimes.

Thanks
Wen Congyang.

> So we can check whether the entry was allocated by bootmem or not.
> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
> But if the entry was allocated by bootmem, we have no way to free the entry.
> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang
>>
>>> +}
>>> +
>>>   static struct kobj_type memmap_ktype = {
>>> +	.release	= release_firmware_map_entry,
>>>   	.sysfs_ops	= &memmap_attr_ops,
>>>   	.default_attrs	= def_attrs,
>>>   };
>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>   	return 0;
>>>   }
>>>
>>> +/**
>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>> + * memmap entry.
>>> + * @entry: removed entry.
>>> + **/
>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>> +{
>>> +	list_del(&entry->list);
>>> +}
>>> +
>>>   /*
>>>    * Add memmap entry on sysfs
>>>    */
>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>   	return 0;
>>>   }
>>>
>>> +/*
>>> + * Remove memmap entry on sysfs
>>> + */
>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>> +{
>>> +	kobject_put(&entry->kobj);
>>> +}
>>> +
>>> +/*
>>> + * Search memmap entry
>>> + */
>>> +
>>> +struct firmware_map_entry * __meminit
>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>> +{
>>> +	struct firmware_map_entry *entry;
>>> +
>>> +	list_for_each_entry(entry, &map_entries, list)
>>> +		if ((entry->start == start) && (entry->end == end) &&
>>> +		    (!strcmp(entry->type, type)))
>>> +			return entry;
>>> +
>>> +	return NULL;
>>> +}
>>> +
>>>   /**
>>>    * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>    * memory hotplug.
>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>   	return firmware_map_add_entry(start, end, type, entry);
>>>   }
>>>
>>> +/**
>>> + * firmware_map_remove() - remove a firmware mapping entry
>>> + * @start: Start of the memory range.
>>> + * @end:   End of the memory range (inclusive).
>>> + * @type:  Type of the memory range.
>>> + *
>>> + * removes a firmware mapping entry.
>>> + *
>>> + * Returns 0 on success, or -EINVAL if no entry.
>>> + **/
>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>> +{
>>> +	struct firmware_map_entry *entry;
>>> +
>>> +	entry = find_firmware_map_entry(start, end, type);
>>> +	if (!entry)
>>> +		return -EINVAL;
>>> +
>>> +	/* remove the memmap entry */
>>> +	remove_sysfs_fw_map_entry(entry);
>>> +
>>> +	firmware_map_remove_entry(entry);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>>   /*
>>>    * Sysfs functions -------------------------------------------------------------
>>>    */
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/03 15:35, Wen Congyang wrote:
>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>> sysfs files are created. But there is no code to remove these files. The patch
>>> implements the function to remove them.
>>>
>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>         memory which is allocated by bootmem.
>>>
>>> CC: David Rientjes <rientjes@google.com>
>>> CC: Jiang Liu <liuj97@gmail.com>
>>> CC: Len Brown <len.brown@intel.com>
>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>> CC: Paul Mackerras <paulus@samba.org>
>>> CC: Christoph Lameter <cl@linux.com>
>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>
>>> ---
>>>   drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>   include/linux/firmware-map.h |    6 +++
>>>   mm/memory_hotplug.c          |    6 +++
>>>   3 files changed, 81 insertions(+), 1 deletion(-)
>>>
>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>
>>>   int remove_memory(int nid, u64 start, u64 size)
>>>   {
>>> -	return -EBUSY;
>>> +	lock_memory_hotplug();
>>> +	/* remove memmap entry */
>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>> +	unlock_memory_hotplug();
>>> +	return 0;
>>>
>>>   }
>>>   EXPORT_SYMBOL_GPL(remove_memory);
>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>> @@ -25,6 +25,7 @@
>>>
>>>   int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>   int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>
>>>   #else /* CONFIG_FIRMWARE_MEMMAP */
>>>
>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>   	return 0;
>>>   }
>>>
>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>> +{
>>> +	return 0;
>>> +}
>>> +
>>>   #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>
>>>   #endif /* _LINUX_FIRMWARE_MAP_H */
>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>   	.show = memmap_attr_show,
>>>   };
>>>
>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>> +{
>>> +	/*
>>> +	 * FIXME : There is no idea.
>>> +	 *         How to free the entry which allocated bootmem?
>>> +	 */
>>
>> I find a function free_bootmem(), but I am not sure whether it can work here.
> 
> It cannot work here.
> 
>> Another problem: how to check whether the entry uses bootmem?
> 
> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.

This is not true. In my test, I find the page does not have PG_slab sometimes.

Thanks
Wen Congyang.

> So we can check whether the entry was allocated by bootmem or not.
> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
> But if the entry was allocated by bootmem, we have no way to free the entry.
> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang
>>
>>> +}
>>> +
>>>   static struct kobj_type memmap_ktype = {
>>> +	.release	= release_firmware_map_entry,
>>>   	.sysfs_ops	= &memmap_attr_ops,
>>>   	.default_attrs	= def_attrs,
>>>   };
>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>   	return 0;
>>>   }
>>>
>>> +/**
>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>> + * memmap entry.
>>> + * @entry: removed entry.
>>> + **/
>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>> +{
>>> +	list_del(&entry->list);
>>> +}
>>> +
>>>   /*
>>>    * Add memmap entry on sysfs
>>>    */
>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>   	return 0;
>>>   }
>>>
>>> +/*
>>> + * Remove memmap entry on sysfs
>>> + */
>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>> +{
>>> +	kobject_put(&entry->kobj);
>>> +}
>>> +
>>> +/*
>>> + * Search memmap entry
>>> + */
>>> +
>>> +struct firmware_map_entry * __meminit
>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>> +{
>>> +	struct firmware_map_entry *entry;
>>> +
>>> +	list_for_each_entry(entry, &map_entries, list)
>>> +		if ((entry->start == start) && (entry->end == end) &&
>>> +		    (!strcmp(entry->type, type)))
>>> +			return entry;
>>> +
>>> +	return NULL;
>>> +}
>>> +
>>>   /**
>>>    * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>    * memory hotplug.
>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>   	return firmware_map_add_entry(start, end, type, entry);
>>>   }
>>>
>>> +/**
>>> + * firmware_map_remove() - remove a firmware mapping entry
>>> + * @start: Start of the memory range.
>>> + * @end:   End of the memory range (inclusive).
>>> + * @type:  Type of the memory range.
>>> + *
>>> + * removes a firmware mapping entry.
>>> + *
>>> + * Returns 0 on success, or -EINVAL if no entry.
>>> + **/
>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>> +{
>>> +	struct firmware_map_entry *entry;
>>> +
>>> +	entry = find_firmware_map_entry(start, end, type);
>>> +	if (!entry)
>>> +		return -EINVAL;
>>> +
>>> +	/* remove the memmap entry */
>>> +	remove_sysfs_fw_map_entry(entry);
>>> +
>>> +	firmware_map_remove_entry(entry);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>>   /*
>>>    * Sysfs functions -------------------------------------------------------------
>>>    */
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/03 15:35, Wen Congyang wrote:
>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>> sysfs files are created. But there is no code to remove these files. The patch
>>> implements the function to remove them.
>>>
>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>         memory which is allocated by bootmem.
>>>
>>> CC: David Rientjes <rientjes@google.com>
>>> CC: Jiang Liu <liuj97@gmail.com>
>>> CC: Len Brown <len.brown@intel.com>
>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>> CC: Paul Mackerras <paulus@samba.org>
>>> CC: Christoph Lameter <cl@linux.com>
>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>
>>> ---
>>>   drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>   include/linux/firmware-map.h |    6 +++
>>>   mm/memory_hotplug.c          |    6 +++
>>>   3 files changed, 81 insertions(+), 1 deletion(-)
>>>
>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>
>>>   int remove_memory(int nid, u64 start, u64 size)
>>>   {
>>> -	return -EBUSY;
>>> +	lock_memory_hotplug();
>>> +	/* remove memmap entry */
>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>> +	unlock_memory_hotplug();
>>> +	return 0;
>>>
>>>   }
>>>   EXPORT_SYMBOL_GPL(remove_memory);
>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>> @@ -25,6 +25,7 @@
>>>
>>>   int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>   int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>
>>>   #else /* CONFIG_FIRMWARE_MEMMAP */
>>>
>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>   	return 0;
>>>   }
>>>
>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>> +{
>>> +	return 0;
>>> +}
>>> +
>>>   #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>
>>>   #endif /* _LINUX_FIRMWARE_MAP_H */
>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>> ===================================================================
>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>   	.show = memmap_attr_show,
>>>   };
>>>
>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>> +{
>>> +	/*
>>> +	 * FIXME : There is no idea.
>>> +	 *         How to free the entry which allocated bootmem?
>>> +	 */
>>
>> I find a function free_bootmem(), but I am not sure whether it can work here.
> 
> It cannot work here.
> 
>> Another problem: how to check whether the entry uses bootmem?
> 
> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.

This is not true. In my test, I find the page does not have PG_slab sometimes.

Thanks
Wen Congyang.

> So we can check whether the entry was allocated by bootmem or not.
> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
> But if the entry was allocated by bootmem, we have no way to free the entry.
> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang
>>
>>> +}
>>> +
>>>   static struct kobj_type memmap_ktype = {
>>> +	.release	= release_firmware_map_entry,
>>>   	.sysfs_ops	= &memmap_attr_ops,
>>>   	.default_attrs	= def_attrs,
>>>   };
>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>   	return 0;
>>>   }
>>>
>>> +/**
>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>> + * memmap entry.
>>> + * @entry: removed entry.
>>> + **/
>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>> +{
>>> +	list_del(&entry->list);
>>> +}
>>> +
>>>   /*
>>>    * Add memmap entry on sysfs
>>>    */
>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>   	return 0;
>>>   }
>>>
>>> +/*
>>> + * Remove memmap entry on sysfs
>>> + */
>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>> +{
>>> +	kobject_put(&entry->kobj);
>>> +}
>>> +
>>> +/*
>>> + * Search memmap entry
>>> + */
>>> +
>>> +struct firmware_map_entry * __meminit
>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>> +{
>>> +	struct firmware_map_entry *entry;
>>> +
>>> +	list_for_each_entry(entry, &map_entries, list)
>>> +		if ((entry->start == start) && (entry->end == end) &&
>>> +		    (!strcmp(entry->type, type)))
>>> +			return entry;
>>> +
>>> +	return NULL;
>>> +}
>>> +
>>>   /**
>>>    * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>    * memory hotplug.
>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>   	return firmware_map_add_entry(start, end, type, entry);
>>>   }
>>>
>>> +/**
>>> + * firmware_map_remove() - remove a firmware mapping entry
>>> + * @start: Start of the memory range.
>>> + * @end:   End of the memory range (inclusive).
>>> + * @type:  Type of the memory range.
>>> + *
>>> + * removes a firmware mapping entry.
>>> + *
>>> + * Returns 0 on success, or -EINVAL if no entry.
>>> + **/
>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>> +{
>>> +	struct firmware_map_entry *entry;
>>> +
>>> +	entry = find_firmware_map_entry(start, end, type);
>>> +	if (!entry)
>>> +		return -EINVAL;
>>> +
>>> +	/* remove the memmap entry */
>>> +	remove_sysfs_fw_map_entry(entry);
>>> +
>>> +	firmware_map_remove_entry(entry);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>>   /*
>>>    * Sysfs functions -------------------------------------------------------------
>>>    */
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/04 14:08, Wen Congyang wrote:
> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/03 15:35, Wen Congyang wrote:
>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>> implements the function to remove them.
>>>>
>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>          memory which is allocated by bootmem.
>>>>
>>>> CC: David Rientjes <rientjes@google.com>
>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>> CC: Len Brown <len.brown@intel.com>
>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>> CC: Paul Mackerras <paulus@samba.org>
>>>> CC: Christoph Lameter <cl@linux.com>
>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>
>>>> ---
>>>>    drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>    include/linux/firmware-map.h |    6 +++
>>>>    mm/memory_hotplug.c          |    6 +++
>>>>    3 files changed, 81 insertions(+), 1 deletion(-)
>>>>
>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>
>>>>    int remove_memory(int nid, u64 start, u64 size)
>>>>    {
>>>> -	return -EBUSY;
>>>> +	lock_memory_hotplug();
>>>> +	/* remove memmap entry */
>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>> +	unlock_memory_hotplug();
>>>> +	return 0;
>>>>
>>>>    }
>>>>    EXPORT_SYMBOL_GPL(remove_memory);
>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>> @@ -25,6 +25,7 @@
>>>>
>>>>    int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>    int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>
>>>>    #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>
>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>    	return 0;
>>>>    }
>>>>
>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	return 0;
>>>> +}
>>>> +
>>>>    #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>
>>>>    #endif /* _LINUX_FIRMWARE_MAP_H */
>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>    	.show = memmap_attr_show,
>>>>    };
>>>>
>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>> +{
>>>> +	/*
>>>> +	 * FIXME : There is no idea.
>>>> +	 *         How to free the entry which allocated bootmem?
>>>> +	 */
>>>
>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>
>> It cannot work here.
>>
>>> Another problem: how to check whether the entry uses bootmem?
>>
>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
> 
> This is not true. In my test, I find the page does not have PG_slab sometimes.

I think that it depends on the allocated size. firmware_map_entry size is
smaller than PAGE_SIZE. So the page has PG_Slab.

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang.
> 
>> So we can check whether the entry was allocated by bootmem or not.
>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>
>> Thanks,
>> Yasuaki Ishimatsu
>>
>>>
>>> Thanks
>>> Wen Congyang
>>>
>>>> +}
>>>> +
>>>>    static struct kobj_type memmap_ktype = {
>>>> +	.release	= release_firmware_map_entry,
>>>>    	.sysfs_ops	= &memmap_attr_ops,
>>>>    	.default_attrs	= def_attrs,
>>>>    };
>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>    	return 0;
>>>>    }
>>>>
>>>> +/**
>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>> + * memmap entry.
>>>> + * @entry: removed entry.
>>>> + **/
>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>> +{
>>>> +	list_del(&entry->list);
>>>> +}
>>>> +
>>>>    /*
>>>>     * Add memmap entry on sysfs
>>>>     */
>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>    	return 0;
>>>>    }
>>>>
>>>> +/*
>>>> + * Remove memmap entry on sysfs
>>>> + */
>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>> +{
>>>> +	kobject_put(&entry->kobj);
>>>> +}
>>>> +
>>>> +/*
>>>> + * Search memmap entry
>>>> + */
>>>> +
>>>> +struct firmware_map_entry * __meminit
>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	struct firmware_map_entry *entry;
>>>> +
>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>> +		    (!strcmp(entry->type, type)))
>>>> +			return entry;
>>>> +
>>>> +	return NULL;
>>>> +}
>>>> +
>>>>    /**
>>>>     * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>     * memory hotplug.
>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>    	return firmware_map_add_entry(start, end, type, entry);
>>>>    }
>>>>
>>>> +/**
>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>> + * @start: Start of the memory range.
>>>> + * @end:   End of the memory range (inclusive).
>>>> + * @type:  Type of the memory range.
>>>> + *
>>>> + * removes a firmware mapping entry.
>>>> + *
>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>> + **/
>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	struct firmware_map_entry *entry;
>>>> +
>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>> +	if (!entry)
>>>> +		return -EINVAL;
>>>> +
>>>> +	/* remove the memmap entry */
>>>> +	remove_sysfs_fw_map_entry(entry);
>>>> +
>>>> +	firmware_map_remove_entry(entry);
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>>    /*
>>>>     * Sysfs functions -------------------------------------------------------------
>>>>     */
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>>
>>
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 



--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/04 14:08, Wen Congyang wrote:
> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/03 15:35, Wen Congyang wrote:
>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>> implements the function to remove them.
>>>>
>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>          memory which is allocated by bootmem.
>>>>
>>>> CC: David Rientjes <rientjes@google.com>
>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>> CC: Len Brown <len.brown@intel.com>
>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>> CC: Paul Mackerras <paulus@samba.org>
>>>> CC: Christoph Lameter <cl@linux.com>
>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>
>>>> ---
>>>>    drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>    include/linux/firmware-map.h |    6 +++
>>>>    mm/memory_hotplug.c          |    6 +++
>>>>    3 files changed, 81 insertions(+), 1 deletion(-)
>>>>
>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>
>>>>    int remove_memory(int nid, u64 start, u64 size)
>>>>    {
>>>> -	return -EBUSY;
>>>> +	lock_memory_hotplug();
>>>> +	/* remove memmap entry */
>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>> +	unlock_memory_hotplug();
>>>> +	return 0;
>>>>
>>>>    }
>>>>    EXPORT_SYMBOL_GPL(remove_memory);
>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>> @@ -25,6 +25,7 @@
>>>>
>>>>    int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>    int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>
>>>>    #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>
>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>    	return 0;
>>>>    }
>>>>
>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	return 0;
>>>> +}
>>>> +
>>>>    #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>
>>>>    #endif /* _LINUX_FIRMWARE_MAP_H */
>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>    	.show = memmap_attr_show,
>>>>    };
>>>>
>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>> +{
>>>> +	/*
>>>> +	 * FIXME : There is no idea.
>>>> +	 *         How to free the entry which allocated bootmem?
>>>> +	 */
>>>
>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>
>> It cannot work here.
>>
>>> Another problem: how to check whether the entry uses bootmem?
>>
>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
> 
> This is not true. In my test, I find the page does not have PG_slab sometimes.

I think that it depends on the allocated size. firmware_map_entry size is
smaller than PAGE_SIZE. So the page has PG_Slab.

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang.
> 
>> So we can check whether the entry was allocated by bootmem or not.
>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>
>> Thanks,
>> Yasuaki Ishimatsu
>>
>>>
>>> Thanks
>>> Wen Congyang
>>>
>>>> +}
>>>> +
>>>>    static struct kobj_type memmap_ktype = {
>>>> +	.release	= release_firmware_map_entry,
>>>>    	.sysfs_ops	= &memmap_attr_ops,
>>>>    	.default_attrs	= def_attrs,
>>>>    };
>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>    	return 0;
>>>>    }
>>>>
>>>> +/**
>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>> + * memmap entry.
>>>> + * @entry: removed entry.
>>>> + **/
>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>> +{
>>>> +	list_del(&entry->list);
>>>> +}
>>>> +
>>>>    /*
>>>>     * Add memmap entry on sysfs
>>>>     */
>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>    	return 0;
>>>>    }
>>>>
>>>> +/*
>>>> + * Remove memmap entry on sysfs
>>>> + */
>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>> +{
>>>> +	kobject_put(&entry->kobj);
>>>> +}
>>>> +
>>>> +/*
>>>> + * Search memmap entry
>>>> + */
>>>> +
>>>> +struct firmware_map_entry * __meminit
>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	struct firmware_map_entry *entry;
>>>> +
>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>> +		    (!strcmp(entry->type, type)))
>>>> +			return entry;
>>>> +
>>>> +	return NULL;
>>>> +}
>>>> +
>>>>    /**
>>>>     * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>     * memory hotplug.
>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>    	return firmware_map_add_entry(start, end, type, entry);
>>>>    }
>>>>
>>>> +/**
>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>> + * @start: Start of the memory range.
>>>> + * @end:   End of the memory range (inclusive).
>>>> + * @type:  Type of the memory range.
>>>> + *
>>>> + * removes a firmware mapping entry.
>>>> + *
>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>> + **/
>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	struct firmware_map_entry *entry;
>>>> +
>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>> +	if (!entry)
>>>> +		return -EINVAL;
>>>> +
>>>> +	/* remove the memmap entry */
>>>> +	remove_sysfs_fw_map_entry(entry);
>>>> +
>>>> +	firmware_map_remove_entry(entry);
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>>    /*
>>>>     * Sysfs functions -------------------------------------------------------------
>>>>     */
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>>
>>
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/04 14:08, Wen Congyang wrote:
> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/03 15:35, Wen Congyang wrote:
>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>> implements the function to remove them.
>>>>
>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>          memory which is allocated by bootmem.
>>>>
>>>> CC: David Rientjes <rientjes@google.com>
>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>> CC: Len Brown <len.brown@intel.com>
>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>> CC: Paul Mackerras <paulus@samba.org>
>>>> CC: Christoph Lameter <cl@linux.com>
>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>
>>>> ---
>>>>    drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>    include/linux/firmware-map.h |    6 +++
>>>>    mm/memory_hotplug.c          |    6 +++
>>>>    3 files changed, 81 insertions(+), 1 deletion(-)
>>>>
>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>
>>>>    int remove_memory(int nid, u64 start, u64 size)
>>>>    {
>>>> -	return -EBUSY;
>>>> +	lock_memory_hotplug();
>>>> +	/* remove memmap entry */
>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>> +	unlock_memory_hotplug();
>>>> +	return 0;
>>>>
>>>>    }
>>>>    EXPORT_SYMBOL_GPL(remove_memory);
>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>> @@ -25,6 +25,7 @@
>>>>
>>>>    int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>    int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>
>>>>    #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>
>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>    	return 0;
>>>>    }
>>>>
>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	return 0;
>>>> +}
>>>> +
>>>>    #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>
>>>>    #endif /* _LINUX_FIRMWARE_MAP_H */
>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>> ===================================================================
>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>    	.show = memmap_attr_show,
>>>>    };
>>>>
>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>> +{
>>>> +	/*
>>>> +	 * FIXME : There is no idea.
>>>> +	 *         How to free the entry which allocated bootmem?
>>>> +	 */
>>>
>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>
>> It cannot work here.
>>
>>> Another problem: how to check whether the entry uses bootmem?
>>
>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
> 
> This is not true. In my test, I find the page does not have PG_slab sometimes.

I think that it depends on the allocated size. firmware_map_entry size is
smaller than PAGE_SIZE. So the page has PG_Slab.

Thanks,
Yasuaki Ishimatsu

> 
> Thanks
> Wen Congyang.
> 
>> So we can check whether the entry was allocated by bootmem or not.
>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>
>> Thanks,
>> Yasuaki Ishimatsu
>>
>>>
>>> Thanks
>>> Wen Congyang
>>>
>>>> +}
>>>> +
>>>>    static struct kobj_type memmap_ktype = {
>>>> +	.release	= release_firmware_map_entry,
>>>>    	.sysfs_ops	= &memmap_attr_ops,
>>>>    	.default_attrs	= def_attrs,
>>>>    };
>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>    	return 0;
>>>>    }
>>>>
>>>> +/**
>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>> + * memmap entry.
>>>> + * @entry: removed entry.
>>>> + **/
>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>> +{
>>>> +	list_del(&entry->list);
>>>> +}
>>>> +
>>>>    /*
>>>>     * Add memmap entry on sysfs
>>>>     */
>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>    	return 0;
>>>>    }
>>>>
>>>> +/*
>>>> + * Remove memmap entry on sysfs
>>>> + */
>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>> +{
>>>> +	kobject_put(&entry->kobj);
>>>> +}
>>>> +
>>>> +/*
>>>> + * Search memmap entry
>>>> + */
>>>> +
>>>> +struct firmware_map_entry * __meminit
>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	struct firmware_map_entry *entry;
>>>> +
>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>> +		    (!strcmp(entry->type, type)))
>>>> +			return entry;
>>>> +
>>>> +	return NULL;
>>>> +}
>>>> +
>>>>    /**
>>>>     * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>     * memory hotplug.
>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>    	return firmware_map_add_entry(start, end, type, entry);
>>>>    }
>>>>
>>>> +/**
>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>> + * @start: Start of the memory range.
>>>> + * @end:   End of the memory range (inclusive).
>>>> + * @type:  Type of the memory range.
>>>> + *
>>>> + * removes a firmware mapping entry.
>>>> + *
>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>> + **/
>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>> +{
>>>> +	struct firmware_map_entry *entry;
>>>> +
>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>> +	if (!entry)
>>>> +		return -EINVAL;
>>>> +
>>>> +	/* remove the memmap entry */
>>>> +	remove_sysfs_fw_map_entry(entry);
>>>> +
>>>> +	firmware_map_remove_entry(entry);
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>>    /*
>>>>     * Sysfs functions -------------------------------------------------------------
>>>>     */
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>>
>>
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/04 14:08, Wen Congyang wrote:
>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>> Hi Wen,
>>>
>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>> implements the function to remove them.
>>>>>
>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>          memory which is allocated by bootmem.
>>>>>
>>>>> CC: David Rientjes <rientjes@google.com>
>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>> CC: Len Brown <len.brown@intel.com>
>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>
>>>>> ---
>>>>>    drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>    include/linux/firmware-map.h |    6 +++
>>>>>    mm/memory_hotplug.c          |    6 +++
>>>>>    3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>
>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>
>>>>>    int remove_memory(int nid, u64 start, u64 size)
>>>>>    {
>>>>> -	return -EBUSY;
>>>>> +	lock_memory_hotplug();
>>>>> +	/* remove memmap entry */
>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>> +	unlock_memory_hotplug();
>>>>> +	return 0;
>>>>>
>>>>>    }
>>>>>    EXPORT_SYMBOL_GPL(remove_memory);
>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>> @@ -25,6 +25,7 @@
>>>>>
>>>>>    int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>    int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>
>>>>>    #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>
>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>>    #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>
>>>>>    #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>    	.show = memmap_attr_show,
>>>>>    };
>>>>>
>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>> +{
>>>>> +	/*
>>>>> +	 * FIXME : There is no idea.
>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>> +	 */
>>>>
>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>
>>> It cannot work here.
>>>
>>>> Another problem: how to check whether the entry uses bootmem?
>>>
>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>
>> This is not true. In my test, I find the page does not have PG_slab sometimes.
> 
> I think that it depends on the allocated size. firmware_map_entry size is
> smaller than PAGE_SIZE. So the page has PG_Slab.

In my test, I add printk in the function firmware_map_add_hotplug() to display
page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
to verify it).

Thanks
Wen Congyang

> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang.
>>
>>> So we can check whether the entry was allocated by bootmem or not.
>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>
>>> Thanks,
>>> Yasuaki Ishimatsu
>>>
>>>>
>>>> Thanks
>>>> Wen Congyang
>>>>
>>>>> +}
>>>>> +
>>>>>    static struct kobj_type memmap_ktype = {
>>>>> +	.release	= release_firmware_map_entry,
>>>>>    	.sysfs_ops	= &memmap_attr_ops,
>>>>>    	.default_attrs	= def_attrs,
>>>>>    };
>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +/**
>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>> + * memmap entry.
>>>>> + * @entry: removed entry.
>>>>> + **/
>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>> +{
>>>>> +	list_del(&entry->list);
>>>>> +}
>>>>> +
>>>>>    /*
>>>>>     * Add memmap entry on sysfs
>>>>>     */
>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +/*
>>>>> + * Remove memmap entry on sysfs
>>>>> + */
>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>> +{
>>>>> +	kobject_put(&entry->kobj);
>>>>> +}
>>>>> +
>>>>> +/*
>>>>> + * Search memmap entry
>>>>> + */
>>>>> +
>>>>> +struct firmware_map_entry * __meminit
>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	struct firmware_map_entry *entry;
>>>>> +
>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>> +		    (!strcmp(entry->type, type)))
>>>>> +			return entry;
>>>>> +
>>>>> +	return NULL;
>>>>> +}
>>>>> +
>>>>>    /**
>>>>>     * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>     * memory hotplug.
>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>    	return firmware_map_add_entry(start, end, type, entry);
>>>>>    }
>>>>>
>>>>> +/**
>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>> + * @start: Start of the memory range.
>>>>> + * @end:   End of the memory range (inclusive).
>>>>> + * @type:  Type of the memory range.
>>>>> + *
>>>>> + * removes a firmware mapping entry.
>>>>> + *
>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>> + **/
>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	struct firmware_map_entry *entry;
>>>>> +
>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>> +	if (!entry)
>>>>> +		return -EINVAL;
>>>>> +
>>>>> +	/* remove the memmap entry */
>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>> +
>>>>> +	firmware_map_remove_entry(entry);
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>>    /*
>>>>>     * Sysfs functions -------------------------------------------------------------
>>>>>     */
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>>
>>>
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/04 14:08, Wen Congyang wrote:
>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>> Hi Wen,
>>>
>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>> implements the function to remove them.
>>>>>
>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>          memory which is allocated by bootmem.
>>>>>
>>>>> CC: David Rientjes <rientjes@google.com>
>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>> CC: Len Brown <len.brown@intel.com>
>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>
>>>>> ---
>>>>>    drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>    include/linux/firmware-map.h |    6 +++
>>>>>    mm/memory_hotplug.c          |    6 +++
>>>>>    3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>
>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>
>>>>>    int remove_memory(int nid, u64 start, u64 size)
>>>>>    {
>>>>> -	return -EBUSY;
>>>>> +	lock_memory_hotplug();
>>>>> +	/* remove memmap entry */
>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>> +	unlock_memory_hotplug();
>>>>> +	return 0;
>>>>>
>>>>>    }
>>>>>    EXPORT_SYMBOL_GPL(remove_memory);
>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>> @@ -25,6 +25,7 @@
>>>>>
>>>>>    int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>    int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>
>>>>>    #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>
>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>>    #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>
>>>>>    #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>    	.show = memmap_attr_show,
>>>>>    };
>>>>>
>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>> +{
>>>>> +	/*
>>>>> +	 * FIXME : There is no idea.
>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>> +	 */
>>>>
>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>
>>> It cannot work here.
>>>
>>>> Another problem: how to check whether the entry uses bootmem?
>>>
>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>
>> This is not true. In my test, I find the page does not have PG_slab sometimes.
> 
> I think that it depends on the allocated size. firmware_map_entry size is
> smaller than PAGE_SIZE. So the page has PG_Slab.

In my test, I add printk in the function firmware_map_add_hotplug() to display
page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
to verify it).

Thanks
Wen Congyang

> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang.
>>
>>> So we can check whether the entry was allocated by bootmem or not.
>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>
>>> Thanks,
>>> Yasuaki Ishimatsu
>>>
>>>>
>>>> Thanks
>>>> Wen Congyang
>>>>
>>>>> +}
>>>>> +
>>>>>    static struct kobj_type memmap_ktype = {
>>>>> +	.release	= release_firmware_map_entry,
>>>>>    	.sysfs_ops	= &memmap_attr_ops,
>>>>>    	.default_attrs	= def_attrs,
>>>>>    };
>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +/**
>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>> + * memmap entry.
>>>>> + * @entry: removed entry.
>>>>> + **/
>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>> +{
>>>>> +	list_del(&entry->list);
>>>>> +}
>>>>> +
>>>>>    /*
>>>>>     * Add memmap entry on sysfs
>>>>>     */
>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +/*
>>>>> + * Remove memmap entry on sysfs
>>>>> + */
>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>> +{
>>>>> +	kobject_put(&entry->kobj);
>>>>> +}
>>>>> +
>>>>> +/*
>>>>> + * Search memmap entry
>>>>> + */
>>>>> +
>>>>> +struct firmware_map_entry * __meminit
>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	struct firmware_map_entry *entry;
>>>>> +
>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>> +		    (!strcmp(entry->type, type)))
>>>>> +			return entry;
>>>>> +
>>>>> +	return NULL;
>>>>> +}
>>>>> +
>>>>>    /**
>>>>>     * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>     * memory hotplug.
>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>    	return firmware_map_add_entry(start, end, type, entry);
>>>>>    }
>>>>>
>>>>> +/**
>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>> + * @start: Start of the memory range.
>>>>> + * @end:   End of the memory range (inclusive).
>>>>> + * @type:  Type of the memory range.
>>>>> + *
>>>>> + * removes a firmware mapping entry.
>>>>> + *
>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>> + **/
>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	struct firmware_map_entry *entry;
>>>>> +
>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>> +	if (!entry)
>>>>> +		return -EINVAL;
>>>>> +
>>>>> +	/* remove the memmap entry */
>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>> +
>>>>> +	firmware_map_remove_entry(entry);
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>>    /*
>>>>>     * Sysfs functions -------------------------------------------------------------
>>>>>     */
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>>
>>>
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/04 14:08, Wen Congyang wrote:
>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>> Hi Wen,
>>>
>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>> implements the function to remove them.
>>>>>
>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>          memory which is allocated by bootmem.
>>>>>
>>>>> CC: David Rientjes <rientjes@google.com>
>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>> CC: Len Brown <len.brown@intel.com>
>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>
>>>>> ---
>>>>>    drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>    include/linux/firmware-map.h |    6 +++
>>>>>    mm/memory_hotplug.c          |    6 +++
>>>>>    3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>
>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>
>>>>>    int remove_memory(int nid, u64 start, u64 size)
>>>>>    {
>>>>> -	return -EBUSY;
>>>>> +	lock_memory_hotplug();
>>>>> +	/* remove memmap entry */
>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>> +	unlock_memory_hotplug();
>>>>> +	return 0;
>>>>>
>>>>>    }
>>>>>    EXPORT_SYMBOL_GPL(remove_memory);
>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>> @@ -25,6 +25,7 @@
>>>>>
>>>>>    int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>    int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>
>>>>>    #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>
>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>>    #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>
>>>>>    #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>> ===================================================================
>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>    	.show = memmap_attr_show,
>>>>>    };
>>>>>
>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>> +{
>>>>> +	/*
>>>>> +	 * FIXME : There is no idea.
>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>> +	 */
>>>>
>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>
>>> It cannot work here.
>>>
>>>> Another problem: how to check whether the entry uses bootmem?
>>>
>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>
>> This is not true. In my test, I find the page does not have PG_slab sometimes.
> 
> I think that it depends on the allocated size. firmware_map_entry size is
> smaller than PAGE_SIZE. So the page has PG_Slab.

In my test, I add printk in the function firmware_map_add_hotplug() to display
page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
to verify it).

Thanks
Wen Congyang

> 
> Thanks,
> Yasuaki Ishimatsu
> 
>>
>> Thanks
>> Wen Congyang.
>>
>>> So we can check whether the entry was allocated by bootmem or not.
>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>
>>> Thanks,
>>> Yasuaki Ishimatsu
>>>
>>>>
>>>> Thanks
>>>> Wen Congyang
>>>>
>>>>> +}
>>>>> +
>>>>>    static struct kobj_type memmap_ktype = {
>>>>> +	.release	= release_firmware_map_entry,
>>>>>    	.sysfs_ops	= &memmap_attr_ops,
>>>>>    	.default_attrs	= def_attrs,
>>>>>    };
>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +/**
>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>> + * memmap entry.
>>>>> + * @entry: removed entry.
>>>>> + **/
>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>> +{
>>>>> +	list_del(&entry->list);
>>>>> +}
>>>>> +
>>>>>    /*
>>>>>     * Add memmap entry on sysfs
>>>>>     */
>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>    	return 0;
>>>>>    }
>>>>>
>>>>> +/*
>>>>> + * Remove memmap entry on sysfs
>>>>> + */
>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>> +{
>>>>> +	kobject_put(&entry->kobj);
>>>>> +}
>>>>> +
>>>>> +/*
>>>>> + * Search memmap entry
>>>>> + */
>>>>> +
>>>>> +struct firmware_map_entry * __meminit
>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	struct firmware_map_entry *entry;
>>>>> +
>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>> +		    (!strcmp(entry->type, type)))
>>>>> +			return entry;
>>>>> +
>>>>> +	return NULL;
>>>>> +}
>>>>> +
>>>>>    /**
>>>>>     * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>     * memory hotplug.
>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>    	return firmware_map_add_entry(start, end, type, entry);
>>>>>    }
>>>>>
>>>>> +/**
>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>> + * @start: Start of the memory range.
>>>>> + * @end:   End of the memory range (inclusive).
>>>>> + * @type:  Type of the memory range.
>>>>> + *
>>>>> + * removes a firmware mapping entry.
>>>>> + *
>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>> + **/
>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>> +{
>>>>> +	struct firmware_map_entry *entry;
>>>>> +
>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>> +	if (!entry)
>>>>> +		return -EINVAL;
>>>>> +
>>>>> +	/* remove the memmap entry */
>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>> +
>>>>> +	firmware_map_remove_entry(entry);
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>>    /*
>>>>>     * Sysfs functions -------------------------------------------------------------
>>>>>     */
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>>
>>>
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/04 19:01, Wen Congyang wrote:
> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/04 14:08, Wen Congyang wrote:
>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>> Hi Wen,
>>>>
>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>> implements the function to remove them.
>>>>>>
>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>           memory which is allocated by bootmem.
>>>>>>
>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>
>>>>>> ---
>>>>>>     drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>     include/linux/firmware-map.h |    6 +++
>>>>>>     mm/memory_hotplug.c          |    6 +++
>>>>>>     3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>
>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>
>>>>>>     int remove_memory(int nid, u64 start, u64 size)
>>>>>>     {
>>>>>> -	return -EBUSY;
>>>>>> +	lock_memory_hotplug();
>>>>>> +	/* remove memmap entry */
>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>> +	unlock_memory_hotplug();
>>>>>> +	return 0;
>>>>>>
>>>>>>     }
>>>>>>     EXPORT_SYMBOL_GPL(remove_memory);
>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>> @@ -25,6 +25,7 @@
>>>>>>
>>>>>>     int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>     int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>
>>>>>>     #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>
>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	return 0;
>>>>>> +}
>>>>>> +
>>>>>>     #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>
>>>>>>     #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>     	.show = memmap_attr_show,
>>>>>>     };
>>>>>>
>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>> +{
>>>>>> +	/*
>>>>>> +	 * FIXME : There is no idea.
>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>> +	 */
>>>>>
>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>
>>>> It cannot work here.
>>>>
>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>
>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>
>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>
>> I think that it depends on the allocated size. firmware_map_entry size is
>> smaller than PAGE_SIZE. So the page has PG_Slab.
> 
> In my test, I add printk in the function firmware_map_add_hotplug() to display
> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
> to verify it).

How did you check it? Could you send your debug patch?

Thanks,
Yasuaki Ishimatsu

> Thanks
> Wen Congyang
> 
>>
>> Thanks,
>> Yasuaki Ishimatsu
>>
>>>
>>> Thanks
>>> Wen Congyang.
>>>
>>>> So we can check whether the entry was allocated by bootmem or not.
>>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>>
>>>> Thanks,
>>>> Yasuaki Ishimatsu
>>>>
>>>>>
>>>>> Thanks
>>>>> Wen Congyang
>>>>>
>>>>>> +}
>>>>>> +
>>>>>>     static struct kobj_type memmap_ktype = {
>>>>>> +	.release	= release_firmware_map_entry,
>>>>>>     	.sysfs_ops	= &memmap_attr_ops,
>>>>>>     	.default_attrs	= def_attrs,
>>>>>>     };
>>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +/**
>>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>>> + * memmap entry.
>>>>>> + * @entry: removed entry.
>>>>>> + **/
>>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>>> +{
>>>>>> +	list_del(&entry->list);
>>>>>> +}
>>>>>> +
>>>>>>     /*
>>>>>>      * Add memmap entry on sysfs
>>>>>>      */
>>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +/*
>>>>>> + * Remove memmap entry on sysfs
>>>>>> + */
>>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>>> +{
>>>>>> +	kobject_put(&entry->kobj);
>>>>>> +}
>>>>>> +
>>>>>> +/*
>>>>>> + * Search memmap entry
>>>>>> + */
>>>>>> +
>>>>>> +struct firmware_map_entry * __meminit
>>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	struct firmware_map_entry *entry;
>>>>>> +
>>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>>> +		    (!strcmp(entry->type, type)))
>>>>>> +			return entry;
>>>>>> +
>>>>>> +	return NULL;
>>>>>> +}
>>>>>> +
>>>>>>     /**
>>>>>>      * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>>      * memory hotplug.
>>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>>     	return firmware_map_add_entry(start, end, type, entry);
>>>>>>     }
>>>>>>
>>>>>> +/**
>>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>>> + * @start: Start of the memory range.
>>>>>> + * @end:   End of the memory range (inclusive).
>>>>>> + * @type:  Type of the memory range.
>>>>>> + *
>>>>>> + * removes a firmware mapping entry.
>>>>>> + *
>>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>>> + **/
>>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	struct firmware_map_entry *entry;
>>>>>> +
>>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>>> +	if (!entry)
>>>>>> +		return -EINVAL;
>>>>>> +
>>>>>> +	/* remove the memmap entry */
>>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>>> +
>>>>>> +	firmware_map_remove_entry(entry);
>>>>>> +
>>>>>> +	return 0;
>>>>>> +}
>>>>>> +
>>>>>>     /*
>>>>>>      * Sysfs functions -------------------------------------------------------------
>>>>>>      */
>>>>>>
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>>
>>
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 



--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/04 19:01, Wen Congyang wrote:
> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/04 14:08, Wen Congyang wrote:
>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>> Hi Wen,
>>>>
>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>> implements the function to remove them.
>>>>>>
>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>           memory which is allocated by bootmem.
>>>>>>
>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>
>>>>>> ---
>>>>>>     drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>     include/linux/firmware-map.h |    6 +++
>>>>>>     mm/memory_hotplug.c          |    6 +++
>>>>>>     3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>
>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>
>>>>>>     int remove_memory(int nid, u64 start, u64 size)
>>>>>>     {
>>>>>> -	return -EBUSY;
>>>>>> +	lock_memory_hotplug();
>>>>>> +	/* remove memmap entry */
>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>> +	unlock_memory_hotplug();
>>>>>> +	return 0;
>>>>>>
>>>>>>     }
>>>>>>     EXPORT_SYMBOL_GPL(remove_memory);
>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>> @@ -25,6 +25,7 @@
>>>>>>
>>>>>>     int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>     int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>
>>>>>>     #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>
>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	return 0;
>>>>>> +}
>>>>>> +
>>>>>>     #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>
>>>>>>     #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>     	.show = memmap_attr_show,
>>>>>>     };
>>>>>>
>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>> +{
>>>>>> +	/*
>>>>>> +	 * FIXME : There is no idea.
>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>> +	 */
>>>>>
>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>
>>>> It cannot work here.
>>>>
>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>
>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>
>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>
>> I think that it depends on the allocated size. firmware_map_entry size is
>> smaller than PAGE_SIZE. So the page has PG_Slab.
> 
> In my test, I add printk in the function firmware_map_add_hotplug() to display
> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
> to verify it).

How did you check it? Could you send your debug patch?

Thanks,
Yasuaki Ishimatsu

> Thanks
> Wen Congyang
> 
>>
>> Thanks,
>> Yasuaki Ishimatsu
>>
>>>
>>> Thanks
>>> Wen Congyang.
>>>
>>>> So we can check whether the entry was allocated by bootmem or not.
>>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>>
>>>> Thanks,
>>>> Yasuaki Ishimatsu
>>>>
>>>>>
>>>>> Thanks
>>>>> Wen Congyang
>>>>>
>>>>>> +}
>>>>>> +
>>>>>>     static struct kobj_type memmap_ktype = {
>>>>>> +	.release	= release_firmware_map_entry,
>>>>>>     	.sysfs_ops	= &memmap_attr_ops,
>>>>>>     	.default_attrs	= def_attrs,
>>>>>>     };
>>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +/**
>>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>>> + * memmap entry.
>>>>>> + * @entry: removed entry.
>>>>>> + **/
>>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>>> +{
>>>>>> +	list_del(&entry->list);
>>>>>> +}
>>>>>> +
>>>>>>     /*
>>>>>>      * Add memmap entry on sysfs
>>>>>>      */
>>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +/*
>>>>>> + * Remove memmap entry on sysfs
>>>>>> + */
>>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>>> +{
>>>>>> +	kobject_put(&entry->kobj);
>>>>>> +}
>>>>>> +
>>>>>> +/*
>>>>>> + * Search memmap entry
>>>>>> + */
>>>>>> +
>>>>>> +struct firmware_map_entry * __meminit
>>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	struct firmware_map_entry *entry;
>>>>>> +
>>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>>> +		    (!strcmp(entry->type, type)))
>>>>>> +			return entry;
>>>>>> +
>>>>>> +	return NULL;
>>>>>> +}
>>>>>> +
>>>>>>     /**
>>>>>>      * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>>      * memory hotplug.
>>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>>     	return firmware_map_add_entry(start, end, type, entry);
>>>>>>     }
>>>>>>
>>>>>> +/**
>>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>>> + * @start: Start of the memory range.
>>>>>> + * @end:   End of the memory range (inclusive).
>>>>>> + * @type:  Type of the memory range.
>>>>>> + *
>>>>>> + * removes a firmware mapping entry.
>>>>>> + *
>>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>>> + **/
>>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	struct firmware_map_entry *entry;
>>>>>> +
>>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>>> +	if (!entry)
>>>>>> +		return -EINVAL;
>>>>>> +
>>>>>> +	/* remove the memmap entry */
>>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>>> +
>>>>>> +	firmware_map_remove_entry(entry);
>>>>>> +
>>>>>> +	return 0;
>>>>>> +}
>>>>>> +
>>>>>>     /*
>>>>>>      * Sysfs functions -------------------------------------------------------------
>>>>>>      */
>>>>>>
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>>
>>
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/04 19:01, Wen Congyang wrote:
> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/04 14:08, Wen Congyang wrote:
>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>> Hi Wen,
>>>>
>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>> implements the function to remove them.
>>>>>>
>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>           memory which is allocated by bootmem.
>>>>>>
>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>
>>>>>> ---
>>>>>>     drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>     include/linux/firmware-map.h |    6 +++
>>>>>>     mm/memory_hotplug.c          |    6 +++
>>>>>>     3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>
>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>
>>>>>>     int remove_memory(int nid, u64 start, u64 size)
>>>>>>     {
>>>>>> -	return -EBUSY;
>>>>>> +	lock_memory_hotplug();
>>>>>> +	/* remove memmap entry */
>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>> +	unlock_memory_hotplug();
>>>>>> +	return 0;
>>>>>>
>>>>>>     }
>>>>>>     EXPORT_SYMBOL_GPL(remove_memory);
>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>> @@ -25,6 +25,7 @@
>>>>>>
>>>>>>     int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>     int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>
>>>>>>     #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>
>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	return 0;
>>>>>> +}
>>>>>> +
>>>>>>     #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>
>>>>>>     #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>> ===================================================================
>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>     	.show = memmap_attr_show,
>>>>>>     };
>>>>>>
>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>> +{
>>>>>> +	/*
>>>>>> +	 * FIXME : There is no idea.
>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>> +	 */
>>>>>
>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>
>>>> It cannot work here.
>>>>
>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>
>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>
>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>
>> I think that it depends on the allocated size. firmware_map_entry size is
>> smaller than PAGE_SIZE. So the page has PG_Slab.
> 
> In my test, I add printk in the function firmware_map_add_hotplug() to display
> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
> to verify it).

How did you check it? Could you send your debug patch?

Thanks,
Yasuaki Ishimatsu

> Thanks
> Wen Congyang
> 
>>
>> Thanks,
>> Yasuaki Ishimatsu
>>
>>>
>>> Thanks
>>> Wen Congyang.
>>>
>>>> So we can check whether the entry was allocated by bootmem or not.
>>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>>
>>>> Thanks,
>>>> Yasuaki Ishimatsu
>>>>
>>>>>
>>>>> Thanks
>>>>> Wen Congyang
>>>>>
>>>>>> +}
>>>>>> +
>>>>>>     static struct kobj_type memmap_ktype = {
>>>>>> +	.release	= release_firmware_map_entry,
>>>>>>     	.sysfs_ops	= &memmap_attr_ops,
>>>>>>     	.default_attrs	= def_attrs,
>>>>>>     };
>>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +/**
>>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>>> + * memmap entry.
>>>>>> + * @entry: removed entry.
>>>>>> + **/
>>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>>> +{
>>>>>> +	list_del(&entry->list);
>>>>>> +}
>>>>>> +
>>>>>>     /*
>>>>>>      * Add memmap entry on sysfs
>>>>>>      */
>>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>>     	return 0;
>>>>>>     }
>>>>>>
>>>>>> +/*
>>>>>> + * Remove memmap entry on sysfs
>>>>>> + */
>>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>>> +{
>>>>>> +	kobject_put(&entry->kobj);
>>>>>> +}
>>>>>> +
>>>>>> +/*
>>>>>> + * Search memmap entry
>>>>>> + */
>>>>>> +
>>>>>> +struct firmware_map_entry * __meminit
>>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	struct firmware_map_entry *entry;
>>>>>> +
>>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>>> +		    (!strcmp(entry->type, type)))
>>>>>> +			return entry;
>>>>>> +
>>>>>> +	return NULL;
>>>>>> +}
>>>>>> +
>>>>>>     /**
>>>>>>      * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>>      * memory hotplug.
>>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>>     	return firmware_map_add_entry(start, end, type, entry);
>>>>>>     }
>>>>>>
>>>>>> +/**
>>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>>> + * @start: Start of the memory range.
>>>>>> + * @end:   End of the memory range (inclusive).
>>>>>> + * @type:  Type of the memory range.
>>>>>> + *
>>>>>> + * removes a firmware mapping entry.
>>>>>> + *
>>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>>> + **/
>>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>> +{
>>>>>> +	struct firmware_map_entry *entry;
>>>>>> +
>>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>>> +	if (!entry)
>>>>>> +		return -EINVAL;
>>>>>> +
>>>>>> +	/* remove the memmap entry */
>>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>>> +
>>>>>> +	firmware_map_remove_entry(entry);
>>>>>> +
>>>>>> +	return 0;
>>>>>> +}
>>>>>> +
>>>>>>     /*
>>>>>>      * Sysfs functions -------------------------------------------------------------
>>>>>>      */
>>>>>>
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>
>>
>>
>>
>>
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/06/2012 04:27 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/04 19:01, Wen Congyang wrote:
>> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>>> Hi Wen,
>>>
>>> 2012/07/04 14:08, Wen Congyang wrote:
>>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>>> Hi Wen,
>>>>>
>>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>>> implements the function to remove them.
>>>>>>>
>>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>>           memory which is allocated by bootmem.
>>>>>>>
>>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>>
>>>>>>> ---
>>>>>>>     drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>>     include/linux/firmware-map.h |    6 +++
>>>>>>>     mm/memory_hotplug.c          |    6 +++
>>>>>>>     3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>>
>>>>>>>     int remove_memory(int nid, u64 start, u64 size)
>>>>>>>     {
>>>>>>> -	return -EBUSY;
>>>>>>> +	lock_memory_hotplug();
>>>>>>> +	/* remove memmap entry */
>>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>>> +	unlock_memory_hotplug();
>>>>>>> +	return 0;
>>>>>>>
>>>>>>>     }
>>>>>>>     EXPORT_SYMBOL_GPL(remove_memory);
>>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>>> @@ -25,6 +25,7 @@
>>>>>>>
>>>>>>>     int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>>     int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>>
>>>>>>>     #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>
>>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	return 0;
>>>>>>> +}
>>>>>>> +
>>>>>>>     #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>
>>>>>>>     #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>>     	.show = memmap_attr_show,
>>>>>>>     };
>>>>>>>
>>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>>> +{
>>>>>>> +	/*
>>>>>>> +	 * FIXME : There is no idea.
>>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>>> +	 */
>>>>>>
>>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>>
>>>>> It cannot work here.
>>>>>
>>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>>
>>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>>
>>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>>
>>> I think that it depends on the allocated size. firmware_map_entry size is
>>> smaller than PAGE_SIZE. So the page has PG_Slab.
>>
>> In my test, I add printk in the function firmware_map_add_hotplug() to display
>> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
>> to verify it).
> 
> How did you check it? Could you send your debug patch?

When the memory is not allocated from slab, the flags is 0x10000000008000.

>From 8dd51368d6c03edf7edc89cab17441e3741c39c7 Mon Sep 17 00:00:00 2001
From: Wen Congyang <wency@cn.fujitsu.com>
Date: Wed, 4 Jul 2012 16:05:26 +0800
Subject: [PATCH] debug

---
 drivers/firmware/memmap.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
index adc0710..993ba3f 100644
--- a/drivers/firmware/memmap.c
+++ b/drivers/firmware/memmap.c
@@ -21,6 +21,7 @@
 #include <linux/types.h>
 #include <linux/bootmem.h>
 #include <linux/slab.h>
+#include <linux/mm.h>
 
 /*
  * Data types ------------------------------------------------------------------
@@ -160,11 +161,17 @@ static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry)
 int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)
 {
 	struct firmware_map_entry *entry;
+	struct page *entry_page;
 
 	entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
 	if (!entry)
 		return -ENOMEM;
 
+	entry_page = virt_to_page(entry);
+	printk(KERN_WARNING "flags: %lx\n", entry_page->flags);
+	if (PageSlab(entry_page)) {
+		printk(KERN_WARNING "page is allocated from slab\n");
+	}
 	firmware_map_add_entry(start, end, type, entry);
 	/* create the memmap entry */
 	add_sysfs_fw_map_entry(entry);
-- 
1.7.1

Thanks
Wen Congyang

> 
> Thanks,
> Yasuaki Ishimatsu
> 
>> Thanks
>> Wen Congyang
>>
>>>
>>> Thanks,
>>> Yasuaki Ishimatsu
>>>
>>>>
>>>> Thanks
>>>> Wen Congyang.
>>>>
>>>>> So we can check whether the entry was allocated by bootmem or not.
>>>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>>>
>>>>> Thanks,
>>>>> Yasuaki Ishimatsu
>>>>>
>>>>>>
>>>>>> Thanks
>>>>>> Wen Congyang
>>>>>>
>>>>>>> +}
>>>>>>> +
>>>>>>>     static struct kobj_type memmap_ktype = {
>>>>>>> +	.release	= release_firmware_map_entry,
>>>>>>>     	.sysfs_ops	= &memmap_attr_ops,
>>>>>>>     	.default_attrs	= def_attrs,
>>>>>>>     };
>>>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +/**
>>>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>>>> + * memmap entry.
>>>>>>> + * @entry: removed entry.
>>>>>>> + **/
>>>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>>>> +{
>>>>>>> +	list_del(&entry->list);
>>>>>>> +}
>>>>>>> +
>>>>>>>     /*
>>>>>>>      * Add memmap entry on sysfs
>>>>>>>      */
>>>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +/*
>>>>>>> + * Remove memmap entry on sysfs
>>>>>>> + */
>>>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>>>> +{
>>>>>>> +	kobject_put(&entry->kobj);
>>>>>>> +}
>>>>>>> +
>>>>>>> +/*
>>>>>>> + * Search memmap entry
>>>>>>> + */
>>>>>>> +
>>>>>>> +struct firmware_map_entry * __meminit
>>>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	struct firmware_map_entry *entry;
>>>>>>> +
>>>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>>>> +		    (!strcmp(entry->type, type)))
>>>>>>> +			return entry;
>>>>>>> +
>>>>>>> +	return NULL;
>>>>>>> +}
>>>>>>> +
>>>>>>>     /**
>>>>>>>      * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>>>      * memory hotplug.
>>>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>>>     	return firmware_map_add_entry(start, end, type, entry);
>>>>>>>     }
>>>>>>>
>>>>>>> +/**
>>>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>>>> + * @start: Start of the memory range.
>>>>>>> + * @end:   End of the memory range (inclusive).
>>>>>>> + * @type:  Type of the memory range.
>>>>>>> + *
>>>>>>> + * removes a firmware mapping entry.
>>>>>>> + *
>>>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>>>> + **/
>>>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	struct firmware_map_entry *entry;
>>>>>>> +
>>>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>>>> +	if (!entry)
>>>>>>> +		return -EINVAL;
>>>>>>> +
>>>>>>> +	/* remove the memmap entry */
>>>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>>>> +
>>>>>>> +	firmware_map_remove_entry(entry);
>>>>>>> +
>>>>>>> +	return 0;
>>>>>>> +}
>>>>>>> +
>>>>>>>     /*
>>>>>>>      * Sysfs functions -------------------------------------------------------------
>>>>>>>      */
>>>>>>>
>>>>>>> --
>>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>>
>>>>>>
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>>
>>>
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/06/2012 04:27 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/04 19:01, Wen Congyang wrote:
>> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>>> Hi Wen,
>>>
>>> 2012/07/04 14:08, Wen Congyang wrote:
>>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>>> Hi Wen,
>>>>>
>>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>>> implements the function to remove them.
>>>>>>>
>>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>>           memory which is allocated by bootmem.
>>>>>>>
>>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>>
>>>>>>> ---
>>>>>>>     drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>>     include/linux/firmware-map.h |    6 +++
>>>>>>>     mm/memory_hotplug.c          |    6 +++
>>>>>>>     3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>>
>>>>>>>     int remove_memory(int nid, u64 start, u64 size)
>>>>>>>     {
>>>>>>> -	return -EBUSY;
>>>>>>> +	lock_memory_hotplug();
>>>>>>> +	/* remove memmap entry */
>>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>>> +	unlock_memory_hotplug();
>>>>>>> +	return 0;
>>>>>>>
>>>>>>>     }
>>>>>>>     EXPORT_SYMBOL_GPL(remove_memory);
>>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>>> @@ -25,6 +25,7 @@
>>>>>>>
>>>>>>>     int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>>     int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>>
>>>>>>>     #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>
>>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	return 0;
>>>>>>> +}
>>>>>>> +
>>>>>>>     #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>
>>>>>>>     #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>>     	.show = memmap_attr_show,
>>>>>>>     };
>>>>>>>
>>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>>> +{
>>>>>>> +	/*
>>>>>>> +	 * FIXME : There is no idea.
>>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>>> +	 */
>>>>>>
>>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>>
>>>>> It cannot work here.
>>>>>
>>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>>
>>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>>
>>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>>
>>> I think that it depends on the allocated size. firmware_map_entry size is
>>> smaller than PAGE_SIZE. So the page has PG_Slab.
>>
>> In my test, I add printk in the function firmware_map_add_hotplug() to display
>> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
>> to verify it).
> 
> How did you check it? Could you send your debug patch?

When the memory is not allocated from slab, the flags is 0x10000000008000.

>From 8dd51368d6c03edf7edc89cab17441e3741c39c7 Mon Sep 17 00:00:00 2001
From: Wen Congyang <wency@cn.fujitsu.com>
Date: Wed, 4 Jul 2012 16:05:26 +0800
Subject: [PATCH] debug

---
 drivers/firmware/memmap.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
index adc0710..993ba3f 100644
--- a/drivers/firmware/memmap.c
+++ b/drivers/firmware/memmap.c
@@ -21,6 +21,7 @@
 #include <linux/types.h>
 #include <linux/bootmem.h>
 #include <linux/slab.h>
+#include <linux/mm.h>
 
 /*
  * Data types ------------------------------------------------------------------
@@ -160,11 +161,17 @@ static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry)
 int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)
 {
 	struct firmware_map_entry *entry;
+	struct page *entry_page;
 
 	entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
 	if (!entry)
 		return -ENOMEM;
 
+	entry_page = virt_to_page(entry);
+	printk(KERN_WARNING "flags: %lx\n", entry_page->flags);
+	if (PageSlab(entry_page)) {
+		printk(KERN_WARNING "page is allocated from slab\n");
+	}
 	firmware_map_add_entry(start, end, type, entry);
 	/* create the memmap entry */
 	add_sysfs_fw_map_entry(entry);
-- 
1.7.1

Thanks
Wen Congyang

> 
> Thanks,
> Yasuaki Ishimatsu
> 
>> Thanks
>> Wen Congyang
>>
>>>
>>> Thanks,
>>> Yasuaki Ishimatsu
>>>
>>>>
>>>> Thanks
>>>> Wen Congyang.
>>>>
>>>>> So we can check whether the entry was allocated by bootmem or not.
>>>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>>>
>>>>> Thanks,
>>>>> Yasuaki Ishimatsu
>>>>>
>>>>>>
>>>>>> Thanks
>>>>>> Wen Congyang
>>>>>>
>>>>>>> +}
>>>>>>> +
>>>>>>>     static struct kobj_type memmap_ktype = {
>>>>>>> +	.release	= release_firmware_map_entry,
>>>>>>>     	.sysfs_ops	= &memmap_attr_ops,
>>>>>>>     	.default_attrs	= def_attrs,
>>>>>>>     };
>>>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +/**
>>>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>>>> + * memmap entry.
>>>>>>> + * @entry: removed entry.
>>>>>>> + **/
>>>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>>>> +{
>>>>>>> +	list_del(&entry->list);
>>>>>>> +}
>>>>>>> +
>>>>>>>     /*
>>>>>>>      * Add memmap entry on sysfs
>>>>>>>      */
>>>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +/*
>>>>>>> + * Remove memmap entry on sysfs
>>>>>>> + */
>>>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>>>> +{
>>>>>>> +	kobject_put(&entry->kobj);
>>>>>>> +}
>>>>>>> +
>>>>>>> +/*
>>>>>>> + * Search memmap entry
>>>>>>> + */
>>>>>>> +
>>>>>>> +struct firmware_map_entry * __meminit
>>>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	struct firmware_map_entry *entry;
>>>>>>> +
>>>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>>>> +		    (!strcmp(entry->type, type)))
>>>>>>> +			return entry;
>>>>>>> +
>>>>>>> +	return NULL;
>>>>>>> +}
>>>>>>> +
>>>>>>>     /**
>>>>>>>      * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>>>      * memory hotplug.
>>>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>>>     	return firmware_map_add_entry(start, end, type, entry);
>>>>>>>     }
>>>>>>>
>>>>>>> +/**
>>>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>>>> + * @start: Start of the memory range.
>>>>>>> + * @end:   End of the memory range (inclusive).
>>>>>>> + * @type:  Type of the memory range.
>>>>>>> + *
>>>>>>> + * removes a firmware mapping entry.
>>>>>>> + *
>>>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>>>> + **/
>>>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	struct firmware_map_entry *entry;
>>>>>>> +
>>>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>>>> +	if (!entry)
>>>>>>> +		return -EINVAL;
>>>>>>> +
>>>>>>> +	/* remove the memmap entry */
>>>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>>>> +
>>>>>>> +	firmware_map_remove_entry(entry);
>>>>>>> +
>>>>>>> +	return 0;
>>>>>>> +}
>>>>>>> +
>>>>>>>     /*
>>>>>>>      * Sysfs functions -------------------------------------------------------------
>>>>>>>      */
>>>>>>>
>>>>>>> --
>>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>>
>>>>>>
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>>
>>>
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/06/2012 04:27 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/04 19:01, Wen Congyang wrote:
>> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>>> Hi Wen,
>>>
>>> 2012/07/04 14:08, Wen Congyang wrote:
>>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>>> Hi Wen,
>>>>>
>>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>>> implements the function to remove them.
>>>>>>>
>>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>>           memory which is allocated by bootmem.
>>>>>>>
>>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>>
>>>>>>> ---
>>>>>>>     drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>>     include/linux/firmware-map.h |    6 +++
>>>>>>>     mm/memory_hotplug.c          |    6 +++
>>>>>>>     3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>>
>>>>>>>     int remove_memory(int nid, u64 start, u64 size)
>>>>>>>     {
>>>>>>> -	return -EBUSY;
>>>>>>> +	lock_memory_hotplug();
>>>>>>> +	/* remove memmap entry */
>>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>>> +	unlock_memory_hotplug();
>>>>>>> +	return 0;
>>>>>>>
>>>>>>>     }
>>>>>>>     EXPORT_SYMBOL_GPL(remove_memory);
>>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>>> @@ -25,6 +25,7 @@
>>>>>>>
>>>>>>>     int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>>     int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>>
>>>>>>>     #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>
>>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	return 0;
>>>>>>> +}
>>>>>>> +
>>>>>>>     #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>
>>>>>>>     #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>>     	.show = memmap_attr_show,
>>>>>>>     };
>>>>>>>
>>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>>> +{
>>>>>>> +	/*
>>>>>>> +	 * FIXME : There is no idea.
>>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>>> +	 */
>>>>>>
>>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>>
>>>>> It cannot work here.
>>>>>
>>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>>
>>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>>
>>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>>
>>> I think that it depends on the allocated size. firmware_map_entry size is
>>> smaller than PAGE_SIZE. So the page has PG_Slab.
>>
>> In my test, I add printk in the function firmware_map_add_hotplug() to display
>> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
>> to verify it).
> 
> How did you check it? Could you send your debug patch?

When the memory is not allocated from slab, the flags is 0x10000000008000.

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Wen Congyang]

At 07/06/2012 04:27 PM, Yasuaki Ishimatsu Wrote:
> Hi Wen,
> 
> 2012/07/04 19:01, Wen Congyang wrote:
>> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>>> Hi Wen,
>>>
>>> 2012/07/04 14:08, Wen Congyang wrote:
>>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>>> Hi Wen,
>>>>>
>>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>>> implements the function to remove them.
>>>>>>>
>>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>>           memory which is allocated by bootmem.
>>>>>>>
>>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>>
>>>>>>> ---
>>>>>>>     drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>>     include/linux/firmware-map.h |    6 +++
>>>>>>>     mm/memory_hotplug.c          |    6 +++
>>>>>>>     3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>>
>>>>>>>     int remove_memory(int nid, u64 start, u64 size)
>>>>>>>     {
>>>>>>> -	return -EBUSY;
>>>>>>> +	lock_memory_hotplug();
>>>>>>> +	/* remove memmap entry */
>>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>>> +	unlock_memory_hotplug();
>>>>>>> +	return 0;
>>>>>>>
>>>>>>>     }
>>>>>>>     EXPORT_SYMBOL_GPL(remove_memory);
>>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>>> @@ -25,6 +25,7 @@
>>>>>>>
>>>>>>>     int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>>     int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>>
>>>>>>>     #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>
>>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	return 0;
>>>>>>> +}
>>>>>>> +
>>>>>>>     #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>
>>>>>>>     #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>>> ===================================================================
>>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>>     	.show = memmap_attr_show,
>>>>>>>     };
>>>>>>>
>>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>>> +{
>>>>>>> +	/*
>>>>>>> +	 * FIXME : There is no idea.
>>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>>> +	 */
>>>>>>
>>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>>
>>>>> It cannot work here.
>>>>>
>>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>>
>>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>>
>>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>>
>>> I think that it depends on the allocated size. firmware_map_entry size is
>>> smaller than PAGE_SIZE. So the page has PG_Slab.
>>
>> In my test, I add printk in the function firmware_map_add_hotplug() to display
>> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
>> to verify it).
> 
> How did you check it? Could you send your debug patch?

When the memory is not allocated from slab, the flags is 0x10000000008000.

>From 8dd51368d6c03edf7edc89cab17441e3741c39c7 Mon Sep 17 00:00:00 2001
From: Wen Congyang <wency@cn.fujitsu.com>
Date: Wed, 4 Jul 2012 16:05:26 +0800
Subject: [PATCH] debug

---
 drivers/firmware/memmap.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
index adc0710..993ba3f 100644
--- a/drivers/firmware/memmap.c
+++ b/drivers/firmware/memmap.c
@@ -21,6 +21,7 @@
 #include <linux/types.h>
 #include <linux/bootmem.h>
 #include <linux/slab.h>
+#include <linux/mm.h>
 
 /*
  * Data types ------------------------------------------------------------------
@@ -160,11 +161,17 @@ static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry)
 int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)
 {
 	struct firmware_map_entry *entry;
+	struct page *entry_page;
 
 	entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
 	if (!entry)
 		return -ENOMEM;
 
+	entry_page = virt_to_page(entry);
+	printk(KERN_WARNING "flags: %lx\n", entry_page->flags);
+	if (PageSlab(entry_page)) {
+		printk(KERN_WARNING "page is allocated from slab\n");
+	}
 	firmware_map_add_entry(start, end, type, entry);
 	/* create the memmap entry */
 	add_sysfs_fw_map_entry(entry);
-- 
1.7.1

Thanks
Wen Congyang

> 
> Thanks,
> Yasuaki Ishimatsu
> 
>> Thanks
>> Wen Congyang
>>
>>>
>>> Thanks,
>>> Yasuaki Ishimatsu
>>>
>>>>
>>>> Thanks
>>>> Wen Congyang.
>>>>
>>>>> So we can check whether the entry was allocated by bootmem or not.
>>>>> If the eantry was allocated by kzalloc(), we can free the entry by kfree().
>>>>> But if the entry was allocated by bootmem, we have no way to free the entry.
>>>>>
>>>>> Thanks,
>>>>> Yasuaki Ishimatsu
>>>>>
>>>>>>
>>>>>> Thanks
>>>>>> Wen Congyang
>>>>>>
>>>>>>> +}
>>>>>>> +
>>>>>>>     static struct kobj_type memmap_ktype = {
>>>>>>> +	.release	= release_firmware_map_entry,
>>>>>>>     	.sysfs_ops	= &memmap_attr_ops,
>>>>>>>     	.default_attrs	= def_attrs,
>>>>>>>     };
>>>>>>> @@ -123,6 +132,16 @@ static int firmware_map_add_entry(u64 st
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +/**
>>>>>>> + * firmware_map_remove_entry() - Does the real work to remove a firmware
>>>>>>> + * memmap entry.
>>>>>>> + * @entry: removed entry.
>>>>>>> + **/
>>>>>>> +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
>>>>>>> +{
>>>>>>> +	list_del(&entry->list);
>>>>>>> +}
>>>>>>> +
>>>>>>>     /*
>>>>>>>      * Add memmap entry on sysfs
>>>>>>>      */
>>>>>>> @@ -144,6 +163,31 @@ static int add_sysfs_fw_map_entry(struct
>>>>>>>     	return 0;
>>>>>>>     }
>>>>>>>
>>>>>>> +/*
>>>>>>> + * Remove memmap entry on sysfs
>>>>>>> + */
>>>>>>> +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>>>>>>> +{
>>>>>>> +	kobject_put(&entry->kobj);
>>>>>>> +}
>>>>>>> +
>>>>>>> +/*
>>>>>>> + * Search memmap entry
>>>>>>> + */
>>>>>>> +
>>>>>>> +struct firmware_map_entry * __meminit
>>>>>>> +find_firmware_map_entry(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	struct firmware_map_entry *entry;
>>>>>>> +
>>>>>>> +	list_for_each_entry(entry, &map_entries, list)
>>>>>>> +		if ((entry->start == start) && (entry->end == end) &&
>>>>>>> +		    (!strcmp(entry->type, type)))
>>>>>>> +			return entry;
>>>>>>> +
>>>>>>> +	return NULL;
>>>>>>> +}
>>>>>>> +
>>>>>>>     /**
>>>>>>>      * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do
>>>>>>>      * memory hotplug.
>>>>>>> @@ -196,6 +240,32 @@ int __init firmware_map_add_early(u64 st
>>>>>>>     	return firmware_map_add_entry(start, end, type, entry);
>>>>>>>     }
>>>>>>>
>>>>>>> +/**
>>>>>>> + * firmware_map_remove() - remove a firmware mapping entry
>>>>>>> + * @start: Start of the memory range.
>>>>>>> + * @end:   End of the memory range (inclusive).
>>>>>>> + * @type:  Type of the memory range.
>>>>>>> + *
>>>>>>> + * removes a firmware mapping entry.
>>>>>>> + *
>>>>>>> + * Returns 0 on success, or -EINVAL if no entry.
>>>>>>> + **/
>>>>>>> +int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>> +{
>>>>>>> +	struct firmware_map_entry *entry;
>>>>>>> +
>>>>>>> +	entry = find_firmware_map_entry(start, end, type);
>>>>>>> +	if (!entry)
>>>>>>> +		return -EINVAL;
>>>>>>> +
>>>>>>> +	/* remove the memmap entry */
>>>>>>> +	remove_sysfs_fw_map_entry(entry);
>>>>>>> +
>>>>>>> +	firmware_map_remove_entry(entry);
>>>>>>> +
>>>>>>> +	return 0;
>>>>>>> +}
>>>>>>> +
>>>>>>>     /*
>>>>>>>      * Sysfs functions -------------------------------------------------------------
>>>>>>>      */
>>>>>>>
>>>>>>> --
>>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>>
>>>>>>
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>> Please read the FAQ at  http://www.tux.org/lkml/
>>>>
>>>
>>>
>>>
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>
> 
> 
> 
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/06 18:20, Wen Congyang wrote:
> At 07/06/2012 04:27 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/04 19:01, Wen Congyang wrote:
>>> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>>>> Hi Wen,
>>>>
>>>> 2012/07/04 14:08, Wen Congyang wrote:
>>>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>>>> Hi Wen,
>>>>>>
>>>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>>>> implements the function to remove them.
>>>>>>>>
>>>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>>>            memory which is allocated by bootmem.
>>>>>>>>
>>>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>>>
>>>>>>>> ---
>>>>>>>>      drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>>>      include/linux/firmware-map.h |    6 +++
>>>>>>>>      mm/memory_hotplug.c          |    6 +++
>>>>>>>>      3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>>>
>>>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>>>
>>>>>>>>      int remove_memory(int nid, u64 start, u64 size)
>>>>>>>>      {
>>>>>>>> -	return -EBUSY;
>>>>>>>> +	lock_memory_hotplug();
>>>>>>>> +	/* remove memmap entry */
>>>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>>>> +	unlock_memory_hotplug();
>>>>>>>> +	return 0;
>>>>>>>>
>>>>>>>>      }
>>>>>>>>      EXPORT_SYMBOL_GPL(remove_memory);
>>>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>>>> @@ -25,6 +25,7 @@
>>>>>>>>
>>>>>>>>      int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>>>      int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>>>
>>>>>>>>      #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>>
>>>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>>>      	return 0;
>>>>>>>>      }
>>>>>>>>
>>>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>>> +{
>>>>>>>> +	return 0;
>>>>>>>> +}
>>>>>>>> +
>>>>>>>>      #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>>
>>>>>>>>      #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>>>      	.show = memmap_attr_show,
>>>>>>>>      };
>>>>>>>>
>>>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>>>> +{
>>>>>>>> +	/*
>>>>>>>> +	 * FIXME : There is no idea.
>>>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>>>> +	 */
>>>>>>>
>>>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>>>
>>>>>> It cannot work here.
>>>>>>
>>>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>>>
>>>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>>>
>>>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>>>
>>>> I think that it depends on the allocated size. firmware_map_entry size is
>>>> smaller than PAGE_SIZE. So the page has PG_Slab.
>>>
>>> In my test, I add printk in the function firmware_map_add_hotplug() to display
>>> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
>>> to verify it).
>>
>> How did you check it? Could you send your debug patch?
> 
> When the memory is not allocated from slab, the flags is 0x10000000008000.

Thank you for sending the patch.
I think the page to not have PageSlab is a compound page. So we can check
whether the entry is allocate from bootmem or not as follow:

static void release_firmware_map_entry(struct kobject *kobj)
{
	struct firmware_map_entry *entry = to_memmap_entry(kobj);
	struct page *head_page;

	head_page = virt_to_head_page(entry);
	if (PageSlab(head_page))
		kfree(etnry);
	else
		/* the entry is allocated from bootmem */
}

Thanks,
Yasuaki Ishimatsu

> 
>  From 8dd51368d6c03edf7edc89cab17441e3741c39c7 Mon Sep 17 00:00:00 2001
> From: Wen Congyang <wency@cn.fujitsu.com>
> Date: Wed, 4 Jul 2012 16:05:26 +0800
> Subject: [PATCH] debug
> 
> ---
>   drivers/firmware/memmap.c |    7 +++++++
>   1 files changed, 7 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
> index adc0710..993ba3f 100644
> --- a/drivers/firmware/memmap.c
> +++ b/drivers/firmware/memmap.c
> @@ -21,6 +21,7 @@
>   #include <linux/types.h>
>   #include <linux/bootmem.h>
>   #include <linux/slab.h>
> +#include <linux/mm.h>
>   
>   /*
>    * Data types ------------------------------------------------------------------
> @@ -160,11 +161,17 @@ static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>   int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)
>   {
>   	struct firmware_map_entry *entry;
> +	struct page *entry_page;
>   
>   	entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
>   	if (!entry)
>   		return -ENOMEM;
>   
> +	entry_page = virt_to_page(entry);
> +	printk(KERN_WARNING "flags: %lx\n", entry_page->flags);
> +	if (PageSlab(entry_page)) {
> +		printk(KERN_WARNING "page is allocated from slab\n");
> +	}
>   	firmware_map_add_entry(start, end, type, entry);
>   	/* create the memmap entry */
>   	add_sysfs_fw_map_entry(entry);
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/06 18:20, Wen Congyang wrote:
> At 07/06/2012 04:27 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/04 19:01, Wen Congyang wrote:
>>> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>>>> Hi Wen,
>>>>
>>>> 2012/07/04 14:08, Wen Congyang wrote:
>>>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>>>> Hi Wen,
>>>>>>
>>>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>>>> implements the function to remove them.
>>>>>>>>
>>>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>>>            memory which is allocated by bootmem.
>>>>>>>>
>>>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>>>
>>>>>>>> ---
>>>>>>>>      drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>>>      include/linux/firmware-map.h |    6 +++
>>>>>>>>      mm/memory_hotplug.c          |    6 +++
>>>>>>>>      3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>>>
>>>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>>>
>>>>>>>>      int remove_memory(int nid, u64 start, u64 size)
>>>>>>>>      {
>>>>>>>> -	return -EBUSY;
>>>>>>>> +	lock_memory_hotplug();
>>>>>>>> +	/* remove memmap entry */
>>>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>>>> +	unlock_memory_hotplug();
>>>>>>>> +	return 0;
>>>>>>>>
>>>>>>>>      }
>>>>>>>>      EXPORT_SYMBOL_GPL(remove_memory);
>>>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>>>> @@ -25,6 +25,7 @@
>>>>>>>>
>>>>>>>>      int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>>>      int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>>>
>>>>>>>>      #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>>
>>>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>>>      	return 0;
>>>>>>>>      }
>>>>>>>>
>>>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>>> +{
>>>>>>>> +	return 0;
>>>>>>>> +}
>>>>>>>> +
>>>>>>>>      #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>>
>>>>>>>>      #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>>>      	.show = memmap_attr_show,
>>>>>>>>      };
>>>>>>>>
>>>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>>>> +{
>>>>>>>> +	/*
>>>>>>>> +	 * FIXME : There is no idea.
>>>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>>>> +	 */
>>>>>>>
>>>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>>>
>>>>>> It cannot work here.
>>>>>>
>>>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>>>
>>>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>>>
>>>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>>>
>>>> I think that it depends on the allocated size. firmware_map_entry size is
>>>> smaller than PAGE_SIZE. So the page has PG_Slab.
>>>
>>> In my test, I add printk in the function firmware_map_add_hotplug() to display
>>> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
>>> to verify it).
>>
>> How did you check it? Could you send your debug patch?
> 
> When the memory is not allocated from slab, the flags is 0x10000000008000.

Thank you for sending the patch.
I think the page to not have PageSlab is a compound page. So we can check
whether the entry is allocate from bootmem or not as follow:

static void release_firmware_map_entry(struct kobject *kobj)
{
	struct firmware_map_entry *entry = to_memmap_entry(kobj);
	struct page *head_page;

	head_page = virt_to_head_page(entry);
	if (PageSlab(head_page))
		kfree(etnry);
	else
		/* the entry is allocated from bootmem */
}

Thanks,
Yasuaki Ishimatsu

> 
>  From 8dd51368d6c03edf7edc89cab17441e3741c39c7 Mon Sep 17 00:00:00 2001
> From: Wen Congyang <wency@cn.fujitsu.com>
> Date: Wed, 4 Jul 2012 16:05:26 +0800
> Subject: [PATCH] debug
> 
> ---
>   drivers/firmware/memmap.c |    7 +++++++
>   1 files changed, 7 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
> index adc0710..993ba3f 100644
> --- a/drivers/firmware/memmap.c
> +++ b/drivers/firmware/memmap.c
> @@ -21,6 +21,7 @@
>   #include <linux/types.h>
>   #include <linux/bootmem.h>
>   #include <linux/slab.h>
> +#include <linux/mm.h>
>   
>   /*
>    * Data types ------------------------------------------------------------------
> @@ -160,11 +161,17 @@ static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>   int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)
>   {
>   	struct firmware_map_entry *entry;
> +	struct page *entry_page;
>   
>   	entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
>   	if (!entry)
>   		return -ENOMEM;
>   
> +	entry_page = virt_to_page(entry);
> +	printk(KERN_WARNING "flags: %lx\n", entry_page->flags);
> +	if (PageSlab(entry_page)) {
> +		printk(KERN_WARNING "page is allocated from slab\n");
> +	}
>   	firmware_map_add_entry(start, end, type, entry);
>   	/* create the memmap entry */
>   	add_sysfs_fw_map_entry(entry);
> 

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/06 18:20, Wen Congyang wrote:
> At 07/06/2012 04:27 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/04 19:01, Wen Congyang wrote:
>>> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>>>> Hi Wen,
>>>>
>>>> 2012/07/04 14:08, Wen Congyang wrote:
>>>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>>>> Hi Wen,
>>>>>>
>>>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>>>> implements the function to remove them.
>>>>>>>>
>>>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>>>            memory which is allocated by bootmem.
>>>>>>>>
>>>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>>>
>>>>>>>> ---
>>>>>>>>      drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>>>      include/linux/firmware-map.h |    6 +++
>>>>>>>>      mm/memory_hotplug.c          |    6 +++
>>>>>>>>      3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>>>
>>>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>>>
>>>>>>>>      int remove_memory(int nid, u64 start, u64 size)
>>>>>>>>      {
>>>>>>>> -	return -EBUSY;
>>>>>>>> +	lock_memory_hotplug();
>>>>>>>> +	/* remove memmap entry */
>>>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>>>> +	unlock_memory_hotplug();
>>>>>>>> +	return 0;
>>>>>>>>
>>>>>>>>      }
>>>>>>>>      EXPORT_SYMBOL_GPL(remove_memory);
>>>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>>>> @@ -25,6 +25,7 @@
>>>>>>>>
>>>>>>>>      int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>>>      int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>>>
>>>>>>>>      #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>>
>>>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>>>      	return 0;
>>>>>>>>      }
>>>>>>>>
>>>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>>> +{
>>>>>>>> +	return 0;
>>>>>>>> +}
>>>>>>>> +
>>>>>>>>      #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>>
>>>>>>>>      #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>>>      	.show = memmap_attr_show,
>>>>>>>>      };
>>>>>>>>
>>>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>>>> +{
>>>>>>>> +	/*
>>>>>>>> +	 * FIXME : There is no idea.
>>>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>>>> +	 */
>>>>>>>
>>>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>>>
>>>>>> It cannot work here.
>>>>>>
>>>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>>>
>>>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>>>
>>>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>>>
>>>> I think that it depends on the allocated size. firmware_map_entry size is
>>>> smaller than PAGE_SIZE. So the page has PG_Slab.
>>>
>>> In my test, I add printk in the function firmware_map_add_hotplug() to display
>>> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
>>> to verify it).
>>
>> How did you check it? Could you send your debug patch?
> 
> When the memory is not allocated from slab, the flags is 0x10000000008000.

Thank you for sending the patch.
I think the page to not have PageSlab is a compound page. So we can check
whether the entry is allocate from bootmem or not as follow:

static void release_firmware_map_entry(struct kobject *kobj)
{
	struct firmware_map_entry *entry = to_memmap_entry(kobj);
	struct page *head_page;

	head_page = virt_to_head_page(entry);
	if (PageSlab(head_page))
		kfree(etnry);
	else
		/* the entry is allocated from bootmem */
}

Thanks,
Yasuaki Ishimatsu

> 
>  From 8dd51368d6c03edf7edc89cab17441e3741c39c7 Mon Sep 17 00:00:00 2001
> From: Wen Congyang <wency@cn.fujitsu.com>
> Date: Wed, 4 Jul 2012 16:05:26 +0800
> Subject: [PATCH] debug
> 
> ---
>   drivers/firmware/memmap.c |    7 +++++++
>   1 files changed, 7 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
> index adc0710..993ba3f 100644
> --- a/drivers/firmware/memmap.c
> +++ b/drivers/firmware/memmap.c
> @@ -21,6 +21,7 @@
>   #include <linux/types.h>
>   #include <linux/bootmem.h>
>   #include <linux/slab.h>
> +#include <linux/mm.h>
>   
>   /*
>    * Data types ------------------------------------------------------------------
> @@ -160,11 +161,17 @@ static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>   int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)
>   {
>   	struct firmware_map_entry *entry;
> +	struct page *entry_page;
>   
>   	entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
>   	if (!entry)
>   		return -ENOMEM;
>   
> +	entry_page = virt_to_page(entry);
> +	printk(KERN_WARNING "flags: %lx\n", entry_page->flags);
> +	if (PageSlab(entry_page)) {
> +		printk(KERN_WARNING "page is allocated from slab\n");
> +	}
>   	firmware_map_add_entry(start, end, type, entry);
>   	/* create the memmap entry */
>   	add_sysfs_fw_map_entry(entry);
> 



--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

Re: [RFC PATCH v2 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs

[Yasuaki Ishimatsu]

Hi Wen,

2012/07/06 18:20, Wen Congyang wrote:
> At 07/06/2012 04:27 PM, Yasuaki Ishimatsu Wrote:
>> Hi Wen,
>>
>> 2012/07/04 19:01, Wen Congyang wrote:
>>> At 07/04/2012 01:52 PM, Yasuaki Ishimatsu Wrote:
>>>> Hi Wen,
>>>>
>>>> 2012/07/04 14:08, Wen Congyang wrote:
>>>>> At 07/04/2012 12:45 PM, Yasuaki Ishimatsu Wrote:
>>>>>> Hi Wen,
>>>>>>
>>>>>> 2012/07/03 15:35, Wen Congyang wrote:
>>>>>>> At 07/03/2012 01:56 PM, Yasuaki Ishimatsu Wrote:
>>>>>>>> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
>>>>>>>> sysfs files are created. But there is no code to remove these files. The patch
>>>>>>>> implements the function to remove them.
>>>>>>>>
>>>>>>>> Note : The code does not free firmware_map_entry since there is no way to free
>>>>>>>>            memory which is allocated by bootmem.
>>>>>>>>
>>>>>>>> CC: David Rientjes <rientjes@google.com>
>>>>>>>> CC: Jiang Liu <liuj97@gmail.com>
>>>>>>>> CC: Len Brown <len.brown@intel.com>
>>>>>>>> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>>>>>>> CC: Paul Mackerras <paulus@samba.org>
>>>>>>>> CC: Christoph Lameter <cl@linux.com>
>>>>>>>> Cc: Minchan Kim <minchan.kim@gmail.com>
>>>>>>>> CC: Andrew Morton <akpm@linux-foundation.org>
>>>>>>>> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>>>>>> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>>>>>>>>
>>>>>>>> ---
>>>>>>>>      drivers/firmware/memmap.c    |   70 +++++++++++++++++++++++++++++++++++++++++++
>>>>>>>>      include/linux/firmware-map.h |    6 +++
>>>>>>>>      mm/memory_hotplug.c          |    6 +++
>>>>>>>>      3 files changed, 81 insertions(+), 1 deletion(-)
>>>>>>>>
>>>>>>>> Index: linux-3.5-rc4/mm/memory_hotplug.c
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/mm/memory_hotplug.c	2012-07-03 14:22:00.190240794 +0900
>>>>>>>> +++ linux-3.5-rc4/mm/memory_hotplug.c	2012-07-03 14:22:03.549198802 +0900
>>>>>>>> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory);
>>>>>>>>
>>>>>>>>      int remove_memory(int nid, u64 start, u64 size)
>>>>>>>>      {
>>>>>>>> -	return -EBUSY;
>>>>>>>> +	lock_memory_hotplug();
>>>>>>>> +	/* remove memmap entry */
>>>>>>>> +	firmware_map_remove(start, start + size - 1, "System RAM");
>>>>>>>> +	unlock_memory_hotplug();
>>>>>>>> +	return 0;
>>>>>>>>
>>>>>>>>      }
>>>>>>>>      EXPORT_SYMBOL_GPL(remove_memory);
>>>>>>>> Index: linux-3.5-rc4/include/linux/firmware-map.h
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/include/linux/firmware-map.h	2012-07-03 14:21:45.766421116 +0900
>>>>>>>> +++ linux-3.5-rc4/include/linux/firmware-map.h	2012-07-03 14:22:03.550198789 +0900
>>>>>>>> @@ -25,6 +25,7 @@
>>>>>>>>
>>>>>>>>      int firmware_map_add_early(u64 start, u64 end, const char *type);
>>>>>>>>      int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
>>>>>>>> +int firmware_map_remove(u64 start, u64 end, const char *type);
>>>>>>>>
>>>>>>>>      #else /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>>
>>>>>>>> @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl
>>>>>>>>      	return 0;
>>>>>>>>      }
>>>>>>>>
>>>>>>>> +static inline int firmware_map_remove(u64 start, u64 end, const char *type)
>>>>>>>> +{
>>>>>>>> +	return 0;
>>>>>>>> +}
>>>>>>>> +
>>>>>>>>      #endif /* CONFIG_FIRMWARE_MEMMAP */
>>>>>>>>
>>>>>>>>      #endif /* _LINUX_FIRMWARE_MAP_H */
>>>>>>>> Index: linux-3.5-rc4/drivers/firmware/memmap.c
>>>>>>>> ===================================================================
>>>>>>>> --- linux-3.5-rc4.orig/drivers/firmware/memmap.c	2012-07-03 14:21:45.761421180 +0900
>>>>>>>> +++ linux-3.5-rc4/drivers/firmware/memmap.c	2012-07-03 14:22:03.569198549 +0900
>>>>>>>> @@ -79,7 +79,16 @@ static const struct sysfs_ops memmap_att
>>>>>>>>      	.show = memmap_attr_show,
>>>>>>>>      };
>>>>>>>>
>>>>>>>> +static void release_firmware_map_entry(struct kobject *kobj)
>>>>>>>> +{
>>>>>>>> +	/*
>>>>>>>> +	 * FIXME : There is no idea.
>>>>>>>> +	 *         How to free the entry which allocated bootmem?
>>>>>>>> +	 */
>>>>>>>
>>>>>>> I find a function free_bootmem(), but I am not sure whether it can work here.
>>>>>>
>>>>>> It cannot work here.
>>>>>>
>>>>>>> Another problem: how to check whether the entry uses bootmem?
>>>>>>
>>>>>> When firmware_map_entry is allocated by kzalloc(), the page has PG_slab.
>>>>>
>>>>> This is not true. In my test, I find the page does not have PG_slab sometimes.
>>>>
>>>> I think that it depends on the allocated size. firmware_map_entry size is
>>>> smaller than PAGE_SIZE. So the page has PG_Slab.
>>>
>>> In my test, I add printk in the function firmware_map_add_hotplug() to display
>>> page's flags. And sometimes the page is not allocated by slab(I use PageSlab()
>>> to verify it).
>>
>> How did you check it? Could you send your debug patch?
> 
> When the memory is not allocated from slab, the flags is 0x10000000008000.

Thank you for sending the patch.
I think the page to not have PageSlab is a compound page. So we can check
whether the entry is allocate from bootmem or not as follow:

static void release_firmware_map_entry(struct kobject *kobj)
{
	struct firmware_map_entry *entry = to_memmap_entry(kobj);
	struct page *head_page;

	head_page = virt_to_head_page(entry);
	if (PageSlab(head_page))
		kfree(etnry);
	else
		/* the entry is allocated from bootmem */
}

Thanks,
Yasuaki Ishimatsu

> 
>  From 8dd51368d6c03edf7edc89cab17441e3741c39c7 Mon Sep 17 00:00:00 2001
> From: Wen Congyang <wency@cn.fujitsu.com>
> Date: Wed, 4 Jul 2012 16:05:26 +0800
> Subject: [PATCH] debug
> 
> ---
>   drivers/firmware/memmap.c |    7 +++++++
>   1 files changed, 7 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
> index adc0710..993ba3f 100644
> --- a/drivers/firmware/memmap.c
> +++ b/drivers/firmware/memmap.c
> @@ -21,6 +21,7 @@
>   #include <linux/types.h>
>   #include <linux/bootmem.h>
>   #include <linux/slab.h>
> +#include <linux/mm.h>
>   
>   /*
>    * Data types ------------------------------------------------------------------
> @@ -160,11 +161,17 @@ static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry)
>   int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)
>   {
>   	struct firmware_map_entry *entry;
> +	struct page *entry_page;
>   
>   	entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
>   	if (!entry)
>   		return -ENOMEM;
>   
> +	entry_page = virt_to_page(entry);
> +	printk(KERN_WARNING "flags: %lx\n", entry_page->flags);
> +	if (PageSlab(entry_page)) {
> +		printk(KERN_WARNING "page is allocated from slab\n");
> +	}
>   	firmware_map_add_entry(start, end, type, entry);
>   	/* create the memmap entry */
>   	add_sysfs_fw_map_entry(entry);
>