[patch 122/158] mm: support memblock alloc on the exact node for sparse_buffer_init()

[akpm@linux-foundation.org]

From: Yunfeng Ye <yeyunfeng@huawei.com>
Subject: mm: support memblock alloc on the exact node for sparse_buffer_init()

sparse_buffer_init() use memblock_alloc_try_nid_raw() to allocate memory
for page management structure, if memory allocation fails from specified
node, it will fall back to allocate from other nodes.

Normally, the page management structure will not exceed 2% of the total
memory, but a large continuous block of allocation is needed.  In most
cases, memory allocation from the specified node will succeed, but a node
memory become highly fragmented will fail.  we expect to allocate memory
base section rather than by allocating a large block of memory from other
NUMA nodes

Add memblock_alloc_exact_nid_raw() for this situation, which allocate boot
memory block on the exact node.  If a large contiguous block memory
allocate fail in sparse_buffer_init(), it will fall back to allocate small
block memory base section.

Link: http://lkml.kernel.org/r/66755ea7-ab10-8882-36fd-3e02b03775d5@huawei.com
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/memblock.h |    3 +
 mm/memblock.c            |   65 ++++++++++++++++++++++++++++++-------
 mm/sparse.c              |    2 -
 3 files changed, 58 insertions(+), 12 deletions(-)

--- a/include/linux/memblock.h~mm-support-memblock-alloc-on-the-exact-node-for-sparse_buffer_init
+++ a/include/linux/memblock.h
@@ -358,6 +358,9 @@ static inline phys_addr_t memblock_phys_
 					 MEMBLOCK_ALLOC_ACCESSIBLE);
 }
 
+void *memblock_alloc_exact_nid_raw(phys_addr_t size, phys_addr_t align,
+				 phys_addr_t min_addr, phys_addr_t max_addr,
+				 int nid);
 void *memblock_alloc_try_nid_raw(phys_addr_t size, phys_addr_t align,
 				 phys_addr_t min_addr, phys_addr_t max_addr,
 				 int nid);
--- a/mm/memblock.c~mm-support-memblock-alloc-on-the-exact-node-for-sparse_buffer_init
+++ a/mm/memblock.c
@@ -1319,12 +1319,13 @@ __next_mem_pfn_range_in_zone(u64 *idx, s
  * @start: the lower bound of the memory region to allocate (phys address)
  * @end: the upper bound of the memory region to allocate (phys address)
  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ * @exact_nid: control the allocation fall back to other nodes
  *
  * The allocation is performed from memory region limited by
  * memblock.current_limit if @end == %MEMBLOCK_ALLOC_ACCESSIBLE.
  *
- * If the specified node can not hold the requested memory the
- * allocation falls back to any node in the system
+ * If the specified node can not hold the requested memory and @exact_nid
+ * is false, the allocation falls back to any node in the system.
  *
  * For systems with memory mirroring, the allocation is attempted first
  * from the regions with mirroring enabled and then retried from any
@@ -1338,7 +1339,8 @@ __next_mem_pfn_range_in_zone(u64 *idx, s
  */
 static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
 					phys_addr_t align, phys_addr_t start,
-					phys_addr_t end, int nid)
+					phys_addr_t end, int nid,
+					bool exact_nid)
 {
 	enum memblock_flags flags = choose_memblock_flags();
 	phys_addr_t found;
@@ -1358,7 +1360,7 @@ again:
 	if (found && !memblock_reserve(found, size))
 		goto done;
 
-	if (nid != NUMA_NO_NODE) {
+	if (nid != NUMA_NO_NODE && !exact_nid) {
 		found = memblock_find_in_range_node(size, align, start,
 						    end, NUMA_NO_NODE,
 						    flags);
@@ -1406,7 +1408,8 @@ phys_addr_t __init memblock_phys_alloc_r
 					     phys_addr_t start,
 					     phys_addr_t end)
 {
-	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE);
+	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
+					false);
 }
 
 /**
@@ -1425,7 +1428,7 @@ phys_addr_t __init memblock_phys_alloc_r
 phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
 {
 	return memblock_alloc_range_nid(size, align, 0,
-					MEMBLOCK_ALLOC_ACCESSIBLE, nid);
+					MEMBLOCK_ALLOC_ACCESSIBLE, nid, false);
 }
 
 /**
@@ -1435,6 +1438,7 @@ phys_addr_t __init memblock_phys_alloc_t
  * @min_addr: the lower bound of the memory region to allocate (phys address)
  * @max_addr: the upper bound of the memory region to allocate (phys address)
  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ * @exact_nid: control the allocation fall back to other nodes
  *
  * Allocates memory block using memblock_alloc_range_nid() and
  * converts the returned physical address to virtual.
@@ -1450,7 +1454,7 @@ phys_addr_t __init memblock_phys_alloc_t
 static void * __init memblock_alloc_internal(
 				phys_addr_t size, phys_addr_t align,
 				phys_addr_t min_addr, phys_addr_t max_addr,
-				int nid)
+				int nid, bool exact_nid)
 {
 	phys_addr_t alloc;
 
@@ -1465,11 +1469,13 @@ static void * __init memblock_alloc_inte
 	if (max_addr > memblock.current_limit)
 		max_addr = memblock.current_limit;
 
-	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid);
+	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid,
+					exact_nid);
 
 	/* retry allocation without lower limit */
 	if (!alloc && min_addr)
-		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid);
+		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid,
+						exact_nid);
 
 	if (!alloc)
 		return NULL;
@@ -1478,6 +1484,43 @@ static void * __init memblock_alloc_inte
 }
 
 /**
+ * memblock_alloc_exact_nid_raw - allocate boot memory block on the exact node
+ * without zeroing memory
+ * @size: size of memory block to be allocated in bytes
+ * @align: alignment of the region and block's size
+ * @min_addr: the lower bound of the memory region from where the allocation
+ *	  is preferred (phys address)
+ * @max_addr: the upper bound of the memory region from where the allocation
+ *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
+ *	      allocate only from memory limited by memblock.current_limit value
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ *
+ * Public function, provides additional debug information (including caller
+ * info), if enabled. Does not zero allocated memory.
+ *
+ * Return:
+ * Virtual address of allocated memory block on success, NULL on failure.
+ */
+void * __init memblock_alloc_exact_nid_raw(
+			phys_addr_t size, phys_addr_t align,
+			phys_addr_t min_addr, phys_addr_t max_addr,
+			int nid)
+{
+	void *ptr;
+
+	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
+		     __func__, (u64)size, (u64)align, nid, &min_addr,
+		     &max_addr, (void *)_RET_IP_);
+
+	ptr = memblock_alloc_internal(size, align,
+					   min_addr, max_addr, nid, true);
+	if (ptr && size > 0)
+		page_init_poison(ptr, size);
+
+	return ptr;
+}
+
+/**
  * memblock_alloc_try_nid_raw - allocate boot memory block without zeroing
  * memory and without panicking
  * @size: size of memory block to be allocated in bytes
@@ -1508,7 +1551,7 @@ void * __init memblock_alloc_try_nid_raw
 		     &max_addr, (void *)_RET_IP_);
 
 	ptr = memblock_alloc_internal(size, align,
-					   min_addr, max_addr, nid);
+					   min_addr, max_addr, nid, false);
 	if (ptr && size > 0)
 		page_init_poison(ptr, size);
 
@@ -1543,7 +1586,7 @@ void * __init memblock_alloc_try_nid(
 		     __func__, (u64)size, (u64)align, nid, &min_addr,
 		     &max_addr, (void *)_RET_IP_);
 	ptr = memblock_alloc_internal(size, align,
-					   min_addr, max_addr, nid);
+					   min_addr, max_addr, nid, false);
 	if (ptr)
 		memset(ptr, 0, size);
 
--- a/mm/sparse.c~mm-support-memblock-alloc-on-the-exact-node-for-sparse_buffer_init
+++ a/mm/sparse.c
@@ -486,7 +486,7 @@ static void __init sparse_buffer_init(un
 	 * and we want it to be properly aligned to the section size - this is
 	 * especially the case for VMEMMAP which maps memmap to PMDs
 	 */
-	sparsemap_buf = memblock_alloc_try_nid_raw(size, section_map_size(),
+	sparsemap_buf = memblock_alloc_exact_nid_raw(size, section_map_size(),
 					addr, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
 	sparsemap_buf_end = sparsemap_buf + size;
 }
_