[PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Alexandre Ghiti]

This series fixes sh and sparc that did not advertise their gigantic page
support and then were not able to allocate and free those pages at runtime.
It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
function.
Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
architectures to free boottime allocated gigantic pages although unrelated.

Changes in v6:
- Remove unnecessary goto since the fallthrough path does the same and is
  the 'normal' behaviour, as suggested by Dave Hensen
- Be more explicit in comment in set_max_huge_page: we return an error
  if alloc_contig_range is not defined and the user tries to allocate a
  gigantic page (we keep the same behaviour as before this patch), but we
  now let her free boottime gigantic page, as suggested by Dave Hensen
- Add Acked-by, thanks. 

Changes in v5:
- Fix bug in previous version thanks to Mike Kravetz
- Fix block comments that did not respect coding style thanks to Dave Hensen
- Define ARCH_HAS_GIGANTIC_PAGE only for sparc64 as advised by David Miller
- Factorize "def_bool" and "depends on" thanks to Vlastimil Babka

Changes in v4 as suggested by Dave Hensen:
- Split previous version into small patches
- Do not compile alloc_gigantic** functions for architectures that do not
  support those pages
- Define correct ARCH_HAS_GIGANTIC_PAGE in all arch that support them to avoid
  useless runtime check
- Add comment in set_max_huge_pages to explain that freeing is possible even
  without CONTIG_ALLOC defined
- Remove gigantic_page_supported function across all archs

Changes in v3 as suggested by Vlastimil Babka and Dave Hansen:
- config definition was wrong and is now in mm/Kconfig
- COMPACTION_CORE was renamed in CONTIG_ALLOC

Changes in v2 as suggested by Vlastimil Babka:
- Get rid of ARCH_HAS_GIGANTIC_PAGE
- Get rid of architecture specific gigantic_page_supported
- Factorize CMA or (MEMORY_ISOLATION && COMPACTION) into COMPACTION_CORE 

Alexandre Ghiti (4):
  sh: Advertise gigantic page support
  sparc: Advertise gigantic page support
  mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC
  hugetlb: allow to free gigantic pages regardless of the configuration

 arch/arm64/Kconfig                           |  2 +-
 arch/arm64/include/asm/hugetlb.h             |  4 --
 arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
 arch/powerpc/platforms/Kconfig.cputype       |  2 +-
 arch/s390/Kconfig                            |  2 +-
 arch/s390/include/asm/hugetlb.h              |  3 --
 arch/sh/Kconfig                              |  1 +
 arch/sparc/Kconfig                           |  1 +
 arch/x86/Kconfig                             |  2 +-
 arch/x86/include/asm/hugetlb.h               |  4 --
 arch/x86/mm/hugetlbpage.c                    |  2 +-
 include/linux/gfp.h                          |  4 +-
 mm/Kconfig                                   |  3 ++
 mm/hugetlb.c                                 | 57 ++++++++++++--------
 mm/page_alloc.c                              |  7 ++-
 15 files changed, 50 insertions(+), 51 deletions(-)

-- 
2.20.1

[PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Alexandre Ghiti]

This series fixes sh and sparc that did not advertise their gigantic page
support and then were not able to allocate and free those pages at runtime.
It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
function.
Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
architectures to free boottime allocated gigantic pages although unrelated.

Changes in v6:
- Remove unnecessary goto since the fallthrough path does the same and is
  the 'normal' behaviour, as suggested by Dave Hensen
- Be more explicit in comment in set_max_huge_page: we return an error
  if alloc_contig_range is not defined and the user tries to allocate a
  gigantic page (we keep the same behaviour as before this patch), but we
  now let her free boottime gigantic page, as suggested by Dave Hensen
- Add Acked-by, thanks. 

Changes in v5:
- Fix bug in previous version thanks to Mike Kravetz
- Fix block comments that did not respect coding style thanks to Dave Hensen
- Define ARCH_HAS_GIGANTIC_PAGE only for sparc64 as advised by David Miller
- Factorize "def_bool" and "depends on" thanks to Vlastimil Babka

Changes in v4 as suggested by Dave Hensen:
- Split previous version into small patches
- Do not compile alloc_gigantic** functions for architectures that do not
  support those pages
- Define correct ARCH_HAS_GIGANTIC_PAGE in all arch that support them to avoid
  useless runtime check
- Add comment in set_max_huge_pages to explain that freeing is possible even
  without CONTIG_ALLOC defined
- Remove gigantic_page_supported function across all archs

Changes in v3 as suggested by Vlastimil Babka and Dave Hansen:
- config definition was wrong and is now in mm/Kconfig
- COMPACTION_CORE was renamed in CONTIG_ALLOC

Changes in v2 as suggested by Vlastimil Babka:
- Get rid of ARCH_HAS_GIGANTIC_PAGE
- Get rid of architecture specific gigantic_page_supported
- Factorize CMA or (MEMORY_ISOLATION && COMPACTION) into COMPACTION_CORE 

Alexandre Ghiti (4):
  sh: Advertise gigantic page support
  sparc: Advertise gigantic page support
  mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC
  hugetlb: allow to free gigantic pages regardless of the configuration

 arch/arm64/Kconfig                           |  2 +-
 arch/arm64/include/asm/hugetlb.h             |  4 --
 arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
 arch/powerpc/platforms/Kconfig.cputype       |  2 +-
 arch/s390/Kconfig                            |  2 +-
 arch/s390/include/asm/hugetlb.h              |  3 --
 arch/sh/Kconfig                              |  1 +
 arch/sparc/Kconfig                           |  1 +
 arch/x86/Kconfig                             |  2 +-
 arch/x86/include/asm/hugetlb.h               |  4 --
 arch/x86/mm/hugetlbpage.c                    |  2 +-
 include/linux/gfp.h                          |  4 +-
 mm/Kconfig                                   |  3 ++
 mm/hugetlb.c                                 | 57 ++++++++++++--------
 mm/page_alloc.c                              |  7 ++-
 15 files changed, 50 insertions(+), 51 deletions(-)

-- 
2.20.1

[PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Alexandre Ghiti]

This series fixes sh and sparc that did not advertise their gigantic page
support and then were not able to allocate and free those pages at runtime.
It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
function.
Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
architectures to free boottime allocated gigantic pages although unrelated.

Changes in v6:
- Remove unnecessary goto since the fallthrough path does the same and is
  the 'normal' behaviour, as suggested by Dave Hensen
- Be more explicit in comment in set_max_huge_page: we return an error
  if alloc_contig_range is not defined and the user tries to allocate a
  gigantic page (we keep the same behaviour as before this patch), but we
  now let her free boottime gigantic page, as suggested by Dave Hensen
- Add Acked-by, thanks. 

Changes in v5:
- Fix bug in previous version thanks to Mike Kravetz
- Fix block comments that did not respect coding style thanks to Dave Hensen
- Define ARCH_HAS_GIGANTIC_PAGE only for sparc64 as advised by David Miller
- Factorize "def_bool" and "depends on" thanks to Vlastimil Babka

Changes in v4 as suggested by Dave Hensen:
- Split previous version into small patches
- Do not compile alloc_gigantic** functions for architectures that do not
  support those pages
- Define correct ARCH_HAS_GIGANTIC_PAGE in all arch that support them to avoid
  useless runtime check
- Add comment in set_max_huge_pages to explain that freeing is possible even
  without CONTIG_ALLOC defined
- Remove gigantic_page_supported function across all archs

Changes in v3 as suggested by Vlastimil Babka and Dave Hansen:
- config definition was wrong and is now in mm/Kconfig
- COMPACTION_CORE was renamed in CONTIG_ALLOC

Changes in v2 as suggested by Vlastimil Babka:
- Get rid of ARCH_HAS_GIGANTIC_PAGE
- Get rid of architecture specific gigantic_page_supported
- Factorize CMA or (MEMORY_ISOLATION && COMPACTION) into COMPACTION_CORE 

Alexandre Ghiti (4):
  sh: Advertise gigantic page support
  sparc: Advertise gigantic page support
  mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC
  hugetlb: allow to free gigantic pages regardless of the configuration

 arch/arm64/Kconfig                           |  2 +-
 arch/arm64/include/asm/hugetlb.h             |  4 --
 arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
 arch/powerpc/platforms/Kconfig.cputype       |  2 +-
 arch/s390/Kconfig                            |  2 +-
 arch/s390/include/asm/hugetlb.h              |  3 --
 arch/sh/Kconfig                              |  1 +
 arch/sparc/Kconfig                           |  1 +
 arch/x86/Kconfig                             |  2 +-
 arch/x86/include/asm/hugetlb.h               |  4 --
 arch/x86/mm/hugetlbpage.c                    |  2 +-
 include/linux/gfp.h                          |  4 +-
 mm/Kconfig                                   |  3 ++
 mm/hugetlb.c                                 | 57 ++++++++++++--------
 mm/page_alloc.c                              |  7 ++-
 15 files changed, 50 insertions(+), 51 deletions(-)

-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v6 1/4] sh: Advertise gigantic page support

[Alexandre Ghiti]

sh actually supports gigantic pages and selecting
ARCH_HAS_GIGANTIC_PAGE allows it to allocate and free
gigantic pages at runtime.

At least sdk7786_defconfig exposes such a configuration with
huge pages of 64MB, pages of 4KB and MAX_ORDER = 11:
HPAGE_SHIFT (26) - PAGE_SHIFT (12) = 14 >= MAX_ORDER (11)

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
---
 arch/sh/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index a9c36f95744a..299a17bed67c 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,6 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
+	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
-- 
2.20.1

[PATCH v6 1/4] sh: Advertise gigantic page support

[Alexandre Ghiti]

sh actually supports gigantic pages and selecting
ARCH_HAS_GIGANTIC_PAGE allows it to allocate and free
gigantic pages at runtime.

At least sdk7786_defconfig exposes such a configuration with
huge pages of 64MB, pages of 4KB and MAX_ORDER = 11:
HPAGE_SHIFT (26) - PAGE_SHIFT (12) = 14 >= MAX_ORDER (11)

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
---
 arch/sh/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index a9c36f95744a..299a17bed67c 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,6 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
+	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
-- 
2.20.1

[PATCH v6 1/4] sh: Advertise gigantic page support

[Alexandre Ghiti]

sh actually supports gigantic pages and selecting
ARCH_HAS_GIGANTIC_PAGE allows it to allocate and free
gigantic pages at runtime.

At least sdk7786_defconfig exposes such a configuration with
huge pages of 64MB, pages of 4KB and MAX_ORDER = 11:
HPAGE_SHIFT (26) - PAGE_SHIFT (12) = 14 >= MAX_ORDER (11)

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
---
 arch/sh/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index a9c36f95744a..299a17bed67c 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,6 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
+	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v6 2/4] sparc: Advertise gigantic page support

[Alexandre Ghiti]

sparc actually supports gigantic pages and selecting
ARCH_HAS_GIGANTIC_PAGE allows it to allocate and free
gigantic pages at runtime.

sparc allows configuration such as huge pages of 16GB,
pages of 8KB and MAX_ORDER = 13 (default):
HPAGE_SHIFT (34) - PAGE_SHIFT (13) = 21 >= MAX_ORDER (13)

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: David S. Miller <davem@davemloft.net>
---
 arch/sparc/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index d5dd652fb8cc..0b7f0e0fefa5 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,6 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
+	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
 
 config ARCH_DEFCONFIG
 	string
-- 
2.20.1

[PATCH v6 2/4] sparc: Advertise gigantic page support

[Alexandre Ghiti]

sparc actually supports gigantic pages and selecting
ARCH_HAS_GIGANTIC_PAGE allows it to allocate and free
gigantic pages at runtime.

sparc allows configuration such as huge pages of 16GB,
pages of 8KB and MAX_ORDER = 13 (default):
HPAGE_SHIFT (34) - PAGE_SHIFT (13) = 21 >= MAX_ORDER (13)

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: David S. Miller <davem@davemloft.net>
---
 arch/sparc/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index d5dd652fb8cc..0b7f0e0fefa5 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,6 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
+	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
 
 config ARCH_DEFCONFIG
 	string
-- 
2.20.1

[PATCH v6 2/4] sparc: Advertise gigantic page support

[Alexandre Ghiti]

sparc actually supports gigantic pages and selecting
ARCH_HAS_GIGANTIC_PAGE allows it to allocate and free
gigantic pages at runtime.

sparc allows configuration such as huge pages of 16GB,
pages of 8KB and MAX_ORDER = 13 (default):
HPAGE_SHIFT (34) - PAGE_SHIFT (13) = 21 >= MAX_ORDER (13)

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: David S. Miller <davem@davemloft.net>
---
 arch/sparc/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index d5dd652fb8cc..0b7f0e0fefa5 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,6 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
+	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
 
 config ARCH_DEFCONFIG
 	string
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v6 3/4] mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC

[Alexandre Ghiti]

This condition allows to define alloc_contig_range, so simplify
it into a more accurate naming.

Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
---
 arch/arm64/Kconfig                     | 2 +-
 arch/powerpc/platforms/Kconfig.cputype | 2 +-
 arch/s390/Kconfig                      | 2 +-
 arch/sh/Kconfig                        | 2 +-
 arch/sparc/Kconfig                     | 2 +-
 arch/x86/Kconfig                       | 2 +-
 arch/x86/mm/hugetlbpage.c              | 2 +-
 include/linux/gfp.h                    | 2 +-
 mm/Kconfig                             | 3 +++
 mm/page_alloc.c                        | 3 +--
 10 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a4168d366127..091a513b93e9 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -18,7 +18,7 @@ config ARM64
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
 	select ARCH_HAS_PTE_SPECIAL
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 8c7464c3f27f..f677c8974212 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
 config PPC_RADIX_MMU
 	bool "Radix MMU Support"
 	depends on PPC_BOOK3S_64
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	default y
 	help
 	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index ed554b09eb3f..1c57b83c76f5 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -69,7 +69,7 @@ config S390
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SET_MEMORY
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 299a17bed67c..c7266302691c 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,7 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 0b7f0e0fefa5..ca33c80870e2 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,7 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 
 config ARCH_DEFCONFIG
 	string
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 68261430fe6e..8ba90f3e0038 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -23,7 +23,7 @@ config X86_64
 	def_bool y
 	depends on 64BIT
 	# Options that are inherently 64-bit kernel only:
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_SUPPORTS_INT128
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_SOFT_DIRTY
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 92e4c4b85bba..fab095362c50 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -203,7 +203,7 @@ static __init int setup_hugepagesz(char *opt)
 }
 __setup("hugepagesz=", setup_hugepagesz);
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
+#ifdef CONFIG_CONTIG_ALLOC
 static __init int gigantic_pages_init(void)
 {
 	/* With compaction or CMA we can allocate gigantic pages at runtime */
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 5f5e25fd6149..1f1ad9aeebb9 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -585,7 +585,7 @@ static inline bool pm_suspended_storage(void)
 }
 #endif /* CONFIG_PM_SLEEP */
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
+#ifdef CONFIG_CONTIG_ALLOC
 /* The below functions must be run on a range from a single zone. */
 extern int alloc_contig_range(unsigned long start, unsigned long end,
 			      unsigned migratetype, gfp_t gfp_mask);
diff --git a/mm/Kconfig b/mm/Kconfig
index 25c71eb8a7db..137eadc18732 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -258,6 +258,9 @@ config ARCH_ENABLE_HUGEPAGE_MIGRATION
 config ARCH_ENABLE_THP_MIGRATION
 	bool
 
+config CONTIG_ALLOC
+       def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
+
 config PHYS_ADDR_T_64BIT
 	def_bool 64BIT
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 35fdde041f5c..ac9c45ffb344 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8024,8 +8024,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 	return true;
 }
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
-
+#ifdef CONFIG_CONTIG_ALLOC
 static unsigned long pfn_max_align_down(unsigned long pfn)
 {
 	return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
-- 
2.20.1

[PATCH v6 3/4] mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC

[Alexandre Ghiti]

This condition allows to define alloc_contig_range, so simplify
it into a more accurate naming.

Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
---
 arch/arm64/Kconfig                     | 2 +-
 arch/powerpc/platforms/Kconfig.cputype | 2 +-
 arch/s390/Kconfig                      | 2 +-
 arch/sh/Kconfig                        | 2 +-
 arch/sparc/Kconfig                     | 2 +-
 arch/x86/Kconfig                       | 2 +-
 arch/x86/mm/hugetlbpage.c              | 2 +-
 include/linux/gfp.h                    | 2 +-
 mm/Kconfig                             | 3 +++
 mm/page_alloc.c                        | 3 +--
 10 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a4168d366127..091a513b93e9 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -18,7 +18,7 @@ config ARM64
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
 	select ARCH_HAS_PTE_SPECIAL
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 8c7464c3f27f..f677c8974212 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
 config PPC_RADIX_MMU
 	bool "Radix MMU Support"
 	depends on PPC_BOOK3S_64
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	default y
 	help
 	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index ed554b09eb3f..1c57b83c76f5 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -69,7 +69,7 @@ config S390
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SET_MEMORY
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 299a17bed67c..c7266302691c 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,7 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 0b7f0e0fefa5..ca33c80870e2 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,7 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 
 config ARCH_DEFCONFIG
 	string
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 68261430fe6e..8ba90f3e0038 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -23,7 +23,7 @@ config X86_64
 	def_bool y
 	depends on 64BIT
 	# Options that are inherently 64-bit kernel only:
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_SUPPORTS_INT128
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_SOFT_DIRTY
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 92e4c4b85bba..fab095362c50 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -203,7 +203,7 @@ static __init int setup_hugepagesz(char *opt)
 }
 __setup("hugepagesz=", setup_hugepagesz);
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
+#ifdef CONFIG_CONTIG_ALLOC
 static __init int gigantic_pages_init(void)
 {
 	/* With compaction or CMA we can allocate gigantic pages at runtime */
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 5f5e25fd6149..1f1ad9aeebb9 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -585,7 +585,7 @@ static inline bool pm_suspended_storage(void)
 }
 #endif /* CONFIG_PM_SLEEP */
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
+#ifdef CONFIG_CONTIG_ALLOC
 /* The below functions must be run on a range from a single zone. */
 extern int alloc_contig_range(unsigned long start, unsigned long end,
 			      unsigned migratetype, gfp_t gfp_mask);
diff --git a/mm/Kconfig b/mm/Kconfig
index 25c71eb8a7db..137eadc18732 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -258,6 +258,9 @@ config ARCH_ENABLE_HUGEPAGE_MIGRATION
 config ARCH_ENABLE_THP_MIGRATION
 	bool
 
+config CONTIG_ALLOC
+       def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
+
 config PHYS_ADDR_T_64BIT
 	def_bool 64BIT
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 35fdde041f5c..ac9c45ffb344 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8024,8 +8024,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 	return true;
 }
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
-
+#ifdef CONFIG_CONTIG_ALLOC
 static unsigned long pfn_max_align_down(unsigned long pfn)
 {
 	return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
-- 
2.20.1

[PATCH v6 3/4] mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC

[Alexandre Ghiti]

This condition allows to define alloc_contig_range, so simplify
it into a more accurate naming.

Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
---
 arch/arm64/Kconfig                     | 2 +-
 arch/powerpc/platforms/Kconfig.cputype | 2 +-
 arch/s390/Kconfig                      | 2 +-
 arch/sh/Kconfig                        | 2 +-
 arch/sparc/Kconfig                     | 2 +-
 arch/x86/Kconfig                       | 2 +-
 arch/x86/mm/hugetlbpage.c              | 2 +-
 include/linux/gfp.h                    | 2 +-
 mm/Kconfig                             | 3 +++
 mm/page_alloc.c                        | 3 +--
 10 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a4168d366127..091a513b93e9 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -18,7 +18,7 @@ config ARM64
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
 	select ARCH_HAS_PTE_SPECIAL
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 8c7464c3f27f..f677c8974212 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
 config PPC_RADIX_MMU
 	bool "Radix MMU Support"
 	depends on PPC_BOOK3S_64
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	default y
 	help
 	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index ed554b09eb3f..1c57b83c76f5 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -69,7 +69,7 @@ config S390
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SET_MEMORY
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 299a17bed67c..c7266302691c 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,7 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 0b7f0e0fefa5..ca33c80870e2 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,7 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 
 config ARCH_DEFCONFIG
 	string
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 68261430fe6e..8ba90f3e0038 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -23,7 +23,7 @@ config X86_64
 	def_bool y
 	depends on 64BIT
 	# Options that are inherently 64-bit kernel only:
-	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
+	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
 	select ARCH_SUPPORTS_INT128
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_SOFT_DIRTY
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 92e4c4b85bba..fab095362c50 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -203,7 +203,7 @@ static __init int setup_hugepagesz(char *opt)
 }
 __setup("hugepagesz=", setup_hugepagesz);
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
+#ifdef CONFIG_CONTIG_ALLOC
 static __init int gigantic_pages_init(void)
 {
 	/* With compaction or CMA we can allocate gigantic pages at runtime */
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 5f5e25fd6149..1f1ad9aeebb9 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -585,7 +585,7 @@ static inline bool pm_suspended_storage(void)
 }
 #endif /* CONFIG_PM_SLEEP */
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
+#ifdef CONFIG_CONTIG_ALLOC
 /* The below functions must be run on a range from a single zone. */
 extern int alloc_contig_range(unsigned long start, unsigned long end,
 			      unsigned migratetype, gfp_t gfp_mask);
diff --git a/mm/Kconfig b/mm/Kconfig
index 25c71eb8a7db..137eadc18732 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -258,6 +258,9 @@ config ARCH_ENABLE_HUGEPAGE_MIGRATION
 config ARCH_ENABLE_THP_MIGRATION
 	bool
 
+config CONTIG_ALLOC
+       def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
+
 config PHYS_ADDR_T_64BIT
 	def_bool 64BIT
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 35fdde041f5c..ac9c45ffb344 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8024,8 +8024,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 	return true;
 }
 
-#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
-
+#ifdef CONFIG_CONTIG_ALLOC
 static unsigned long pfn_max_align_down(unsigned long pfn)
 {
 	return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On systems without CONTIG_ALLOC activated but that support gigantic pages,
boottime reserved gigantic pages can not be freed at all. This patch
simply enables the possibility to hand back those pages to memory
allocator.

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: David S. Miller <davem@davemloft.net> [sparc]
---
 arch/arm64/Kconfig                           |  2 +-
 arch/arm64/include/asm/hugetlb.h             |  4 --
 arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
 arch/powerpc/platforms/Kconfig.cputype       |  2 +-
 arch/s390/Kconfig                            |  2 +-
 arch/s390/include/asm/hugetlb.h              |  3 --
 arch/sh/Kconfig                              |  2 +-
 arch/sparc/Kconfig                           |  2 +-
 arch/x86/Kconfig                             |  2 +-
 arch/x86/include/asm/hugetlb.h               |  4 --
 include/linux/gfp.h                          |  2 +-
 mm/hugetlb.c                                 | 57 ++++++++++++--------
 mm/page_alloc.c                              |  4 +-
 13 files changed, 44 insertions(+), 49 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 091a513b93e9..af687eff884a 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -18,7 +18,7 @@ config ARM64
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
 	select ARCH_HAS_PTE_SPECIAL
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index fb6609875455..59893e766824 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
 
 #include <asm-generic/hugetlb.h>
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
-
 #endif /* __ASM_HUGETLB_H */
diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
index 5b0177733994..d04a0bcc2f1c 100644
--- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
+++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
@@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
 	}
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void)
-{
-	return true;
-}
-#endif
-
 /* hugepd entry valid bit */
 #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
 
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index f677c8974212..dc0328de20cd 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
 config PPC_RADIX_MMU
 	bool "Radix MMU Support"
 	depends on PPC_BOOK3S_64
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	default y
 	help
 	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 1c57b83c76f5..d84e536796b1 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -69,7 +69,7 @@ config S390
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SET_MEMORY
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index 2d1afa58a4b6..bd191560efcf 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -116,7 +116,4 @@ static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
 	return pte_modify(pte, newprot);
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
 #endif /* _ASM_S390_HUGETLB_H */
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index c7266302691c..404b12a0d871 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,7 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index ca33c80870e2..234a6bd46e89 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,7 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 
 config ARCH_DEFCONFIG
 	string
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8ba90f3e0038..ff24eaeef211 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -23,7 +23,7 @@ config X86_64
 	def_bool y
 	depends on 64BIT
 	# Options that are inherently 64-bit kernel only:
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_SUPPORTS_INT128
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_SOFT_DIRTY
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index 7469d321f072..f65cfb48cfdd 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -17,8 +17,4 @@ static inline void arch_clear_hugepage_flags(struct page *page)
 {
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
-
 #endif /* _ASM_X86_HUGETLB_H */
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 1f1ad9aeebb9..58ea44bf75de 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -589,8 +589,8 @@ static inline bool pm_suspended_storage(void)
 /* The below functions must be run on a range from a single zone. */
 extern int alloc_contig_range(unsigned long start, unsigned long end,
 			      unsigned migratetype, gfp_t gfp_mask);
-extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
 #endif
+extern void free_contig_range(unsigned long pfn, unsigned int nr_pages);
 
 #ifdef CONFIG_CMA
 /* CMA stuff */
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index afef61656c1e..9fc96ef5aa78 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1058,6 +1058,7 @@ static void free_gigantic_page(struct page *page, unsigned int order)
 	free_contig_range(page_to_pfn(page), 1 << order);
 }
 
+#ifdef CONFIG_CONTIG_ALLOC
 static int __alloc_gigantic_page(unsigned long start_pfn,
 				unsigned long nr_pages, gfp_t gfp_mask)
 {
@@ -1142,11 +1143,20 @@ static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
 
 static void prep_new_huge_page(struct hstate *h, struct page *page, int nid);
 static void prep_compound_gigantic_page(struct page *page, unsigned int order);
+#else /* !CONFIG_CONTIG_ALLOC */
+static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
+					int nid, nodemask_t *nodemask)
+{
+	return NULL;
+}
+#endif /* CONFIG_CONTIG_ALLOC */
 
 #else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */
-static inline bool gigantic_page_supported(void) { return false; }
 static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
-		int nid, nodemask_t *nodemask) { return NULL; }
+					int nid, nodemask_t *nodemask)
+{
+	return NULL;
+}
 static inline void free_gigantic_page(struct page *page, unsigned int order) { }
 static inline void destroy_compound_gigantic_page(struct page *page,
 						unsigned int order) { }
@@ -1156,9 +1166,6 @@ static void update_and_free_page(struct hstate *h, struct page *page)
 {
 	int i;
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported())
-		return;
-
 	h->nr_huge_pages--;
 	h->nr_huge_pages_node[page_to_nid(page)]--;
 	for (i = 0; i < pages_per_huge_page(h); i++) {
@@ -2276,13 +2283,27 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed,
 }
 
 #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages)
-static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
-						nodemask_t *nodes_allowed)
+static int set_max_huge_pages(struct hstate *h, unsigned long count,
+			      nodemask_t *nodes_allowed)
 {
 	unsigned long min_count, ret;
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported())
-		return h->max_huge_pages;
+	spin_lock(&hugetlb_lock);
+
+	/*
+	 * Gigantic pages runtime allocation depend on the capability for large
+	 * page range allocation.
+	 * If the system does not provide this feature, return an error when
+	 * the user tries to allocate gigantic pages but let the user free the
+	 * boottime allocated gigantic pages.
+	 */
+	if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) {
+		if (count > persistent_huge_pages(h)) {
+			spin_unlock(&hugetlb_lock);
+			return -EINVAL;
+		}
+		/* Fall through to decrease pool */
+	}
 
 	/*
 	 * Increase the pool size
@@ -2295,7 +2316,6 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 	 * pool might be one hugepage larger than it needs to be, but
 	 * within all the constraints specified by the sysctls.
 	 */
-	spin_lock(&hugetlb_lock);
 	while (h->surplus_huge_pages && count > persistent_huge_pages(h)) {
 		if (!adjust_pool_surplus(h, nodes_allowed, -1))
 			break;
@@ -2350,9 +2370,10 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 			break;
 	}
 out:
-	ret = persistent_huge_pages(h);
+	h->max_huge_pages = persistent_huge_pages(h);
 	spin_unlock(&hugetlb_lock);
-	return ret;
+
+	return 0;
 }
 
 #define HSTATE_ATTR_RO(_name) \
@@ -2404,11 +2425,6 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
 	int err;
 	NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY);
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
-		err = -EINVAL;
-		goto out;
-	}
-
 	if (nid = NUMA_NO_NODE) {
 		/*
 		 * global hstate attribute
@@ -2428,15 +2444,12 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
 	} else
 		nodes_allowed = &node_states[N_MEMORY];
 
-	h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed);
+	err = set_max_huge_pages(h, count, nodes_allowed);
 
 	if (nodes_allowed != &node_states[N_MEMORY])
 		NODEMASK_FREE(nodes_allowed);
 
-	return len;
-out:
-	NODEMASK_FREE(nodes_allowed);
-	return err;
+	return err ? err : len;
 }
 
 static ssize_t nr_hugepages_store_common(bool obey_mempolicy,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ac9c45ffb344..a4547d90fa7a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8234,8 +8234,9 @@ int alloc_contig_range(unsigned long start, unsigned long end,
 				pfn_max_align_up(end), migratetype);
 	return ret;
 }
+#endif /* CONFIG_CONTIG_ALLOC */
 
-void free_contig_range(unsigned long pfn, unsigned nr_pages)
+void free_contig_range(unsigned long pfn, unsigned int nr_pages)
 {
 	unsigned int count = 0;
 
@@ -8247,7 +8248,6 @@ void free_contig_range(unsigned long pfn, unsigned nr_pages)
 	}
 	WARN(count != 0, "%d pages are still in use!\n", count);
 }
-#endif
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 /*
-- 
2.20.1

[PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On systems without CONTIG_ALLOC activated but that support gigantic pages,
boottime reserved gigantic pages can not be freed at all. This patch
simply enables the possibility to hand back those pages to memory
allocator.

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: David S. Miller <davem@davemloft.net> [sparc]
---
 arch/arm64/Kconfig                           |  2 +-
 arch/arm64/include/asm/hugetlb.h             |  4 --
 arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
 arch/powerpc/platforms/Kconfig.cputype       |  2 +-
 arch/s390/Kconfig                            |  2 +-
 arch/s390/include/asm/hugetlb.h              |  3 --
 arch/sh/Kconfig                              |  2 +-
 arch/sparc/Kconfig                           |  2 +-
 arch/x86/Kconfig                             |  2 +-
 arch/x86/include/asm/hugetlb.h               |  4 --
 include/linux/gfp.h                          |  2 +-
 mm/hugetlb.c                                 | 57 ++++++++++++--------
 mm/page_alloc.c                              |  4 +-
 13 files changed, 44 insertions(+), 49 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 091a513b93e9..af687eff884a 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -18,7 +18,7 @@ config ARM64
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
 	select ARCH_HAS_PTE_SPECIAL
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index fb6609875455..59893e766824 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
 
 #include <asm-generic/hugetlb.h>
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
-
 #endif /* __ASM_HUGETLB_H */
diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
index 5b0177733994..d04a0bcc2f1c 100644
--- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
+++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
@@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
 	}
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void)
-{
-	return true;
-}
-#endif
-
 /* hugepd entry valid bit */
 #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
 
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index f677c8974212..dc0328de20cd 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
 config PPC_RADIX_MMU
 	bool "Radix MMU Support"
 	depends on PPC_BOOK3S_64
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	default y
 	help
 	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 1c57b83c76f5..d84e536796b1 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -69,7 +69,7 @@ config S390
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SET_MEMORY
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index 2d1afa58a4b6..bd191560efcf 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -116,7 +116,4 @@ static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
 	return pte_modify(pte, newprot);
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
 #endif /* _ASM_S390_HUGETLB_H */
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index c7266302691c..404b12a0d871 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,7 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index ca33c80870e2..234a6bd46e89 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,7 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 
 config ARCH_DEFCONFIG
 	string
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8ba90f3e0038..ff24eaeef211 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -23,7 +23,7 @@ config X86_64
 	def_bool y
 	depends on 64BIT
 	# Options that are inherently 64-bit kernel only:
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_SUPPORTS_INT128
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_SOFT_DIRTY
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index 7469d321f072..f65cfb48cfdd 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -17,8 +17,4 @@ static inline void arch_clear_hugepage_flags(struct page *page)
 {
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
-
 #endif /* _ASM_X86_HUGETLB_H */
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 1f1ad9aeebb9..58ea44bf75de 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -589,8 +589,8 @@ static inline bool pm_suspended_storage(void)
 /* The below functions must be run on a range from a single zone. */
 extern int alloc_contig_range(unsigned long start, unsigned long end,
 			      unsigned migratetype, gfp_t gfp_mask);
-extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
 #endif
+extern void free_contig_range(unsigned long pfn, unsigned int nr_pages);
 
 #ifdef CONFIG_CMA
 /* CMA stuff */
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index afef61656c1e..9fc96ef5aa78 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1058,6 +1058,7 @@ static void free_gigantic_page(struct page *page, unsigned int order)
 	free_contig_range(page_to_pfn(page), 1 << order);
 }
 
+#ifdef CONFIG_CONTIG_ALLOC
 static int __alloc_gigantic_page(unsigned long start_pfn,
 				unsigned long nr_pages, gfp_t gfp_mask)
 {
@@ -1142,11 +1143,20 @@ static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
 
 static void prep_new_huge_page(struct hstate *h, struct page *page, int nid);
 static void prep_compound_gigantic_page(struct page *page, unsigned int order);
+#else /* !CONFIG_CONTIG_ALLOC */
+static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
+					int nid, nodemask_t *nodemask)
+{
+	return NULL;
+}
+#endif /* CONFIG_CONTIG_ALLOC */
 
 #else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */
-static inline bool gigantic_page_supported(void) { return false; }
 static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
-		int nid, nodemask_t *nodemask) { return NULL; }
+					int nid, nodemask_t *nodemask)
+{
+	return NULL;
+}
 static inline void free_gigantic_page(struct page *page, unsigned int order) { }
 static inline void destroy_compound_gigantic_page(struct page *page,
 						unsigned int order) { }
@@ -1156,9 +1166,6 @@ static void update_and_free_page(struct hstate *h, struct page *page)
 {
 	int i;
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported())
-		return;
-
 	h->nr_huge_pages--;
 	h->nr_huge_pages_node[page_to_nid(page)]--;
 	for (i = 0; i < pages_per_huge_page(h); i++) {
@@ -2276,13 +2283,27 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed,
 }
 
 #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages)
-static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
-						nodemask_t *nodes_allowed)
+static int set_max_huge_pages(struct hstate *h, unsigned long count,
+			      nodemask_t *nodes_allowed)
 {
 	unsigned long min_count, ret;
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported())
-		return h->max_huge_pages;
+	spin_lock(&hugetlb_lock);
+
+	/*
+	 * Gigantic pages runtime allocation depend on the capability for large
+	 * page range allocation.
+	 * If the system does not provide this feature, return an error when
+	 * the user tries to allocate gigantic pages but let the user free the
+	 * boottime allocated gigantic pages.
+	 */
+	if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) {
+		if (count > persistent_huge_pages(h)) {
+			spin_unlock(&hugetlb_lock);
+			return -EINVAL;
+		}
+		/* Fall through to decrease pool */
+	}
 
 	/*
 	 * Increase the pool size
@@ -2295,7 +2316,6 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 	 * pool might be one hugepage larger than it needs to be, but
 	 * within all the constraints specified by the sysctls.
 	 */
-	spin_lock(&hugetlb_lock);
 	while (h->surplus_huge_pages && count > persistent_huge_pages(h)) {
 		if (!adjust_pool_surplus(h, nodes_allowed, -1))
 			break;
@@ -2350,9 +2370,10 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 			break;
 	}
 out:
-	ret = persistent_huge_pages(h);
+	h->max_huge_pages = persistent_huge_pages(h);
 	spin_unlock(&hugetlb_lock);
-	return ret;
+
+	return 0;
 }
 
 #define HSTATE_ATTR_RO(_name) \
@@ -2404,11 +2425,6 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
 	int err;
 	NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY);
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
-		err = -EINVAL;
-		goto out;
-	}
-
 	if (nid == NUMA_NO_NODE) {
 		/*
 		 * global hstate attribute
@@ -2428,15 +2444,12 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
 	} else
 		nodes_allowed = &node_states[N_MEMORY];
 
-	h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed);
+	err = set_max_huge_pages(h, count, nodes_allowed);
 
 	if (nodes_allowed != &node_states[N_MEMORY])
 		NODEMASK_FREE(nodes_allowed);
 
-	return len;
-out:
-	NODEMASK_FREE(nodes_allowed);
-	return err;
+	return err ? err : len;
 }
 
 static ssize_t nr_hugepages_store_common(bool obey_mempolicy,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ac9c45ffb344..a4547d90fa7a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8234,8 +8234,9 @@ int alloc_contig_range(unsigned long start, unsigned long end,
 				pfn_max_align_up(end), migratetype);
 	return ret;
 }
+#endif /* CONFIG_CONTIG_ALLOC */
 
-void free_contig_range(unsigned long pfn, unsigned nr_pages)
+void free_contig_range(unsigned long pfn, unsigned int nr_pages)
 {
 	unsigned int count = 0;
 
@@ -8247,7 +8248,6 @@ void free_contig_range(unsigned long pfn, unsigned nr_pages)
 	}
 	WARN(count != 0, "%d pages are still in use!\n", count);
 }
-#endif
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 /*
-- 
2.20.1

[PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On systems without CONTIG_ALLOC activated but that support gigantic pages,
boottime reserved gigantic pages can not be freed at all. This patch
simply enables the possibility to hand back those pages to memory
allocator.

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: David S. Miller <davem@davemloft.net> [sparc]
---
 arch/arm64/Kconfig                           |  2 +-
 arch/arm64/include/asm/hugetlb.h             |  4 --
 arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
 arch/powerpc/platforms/Kconfig.cputype       |  2 +-
 arch/s390/Kconfig                            |  2 +-
 arch/s390/include/asm/hugetlb.h              |  3 --
 arch/sh/Kconfig                              |  2 +-
 arch/sparc/Kconfig                           |  2 +-
 arch/x86/Kconfig                             |  2 +-
 arch/x86/include/asm/hugetlb.h               |  4 --
 include/linux/gfp.h                          |  2 +-
 mm/hugetlb.c                                 | 57 ++++++++++++--------
 mm/page_alloc.c                              |  4 +-
 13 files changed, 44 insertions(+), 49 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 091a513b93e9..af687eff884a 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -18,7 +18,7 @@ config ARM64
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
 	select ARCH_HAS_PTE_SPECIAL
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index fb6609875455..59893e766824 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
 
 #include <asm-generic/hugetlb.h>
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
-
 #endif /* __ASM_HUGETLB_H */
diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
index 5b0177733994..d04a0bcc2f1c 100644
--- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
+++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
@@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
 	}
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void)
-{
-	return true;
-}
-#endif
-
 /* hugepd entry valid bit */
 #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
 
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index f677c8974212..dc0328de20cd 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
 config PPC_RADIX_MMU
 	bool "Radix MMU Support"
 	depends on PPC_BOOK3S_64
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	default y
 	help
 	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 1c57b83c76f5..d84e536796b1 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -69,7 +69,7 @@ config S390
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SET_MEMORY
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index 2d1afa58a4b6..bd191560efcf 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -116,7 +116,4 @@ static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
 	return pte_modify(pte, newprot);
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
 #endif /* _ASM_S390_HUGETLB_H */
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index c7266302691c..404b12a0d871 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,7 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index ca33c80870e2..234a6bd46e89 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -90,7 +90,7 @@ config SPARC64
 	select ARCH_CLOCKSOURCE_DATA
 	select ARCH_HAS_PTE_SPECIAL
 	select PCI_DOMAINS if PCI
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 
 config ARCH_DEFCONFIG
 	string
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8ba90f3e0038..ff24eaeef211 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -23,7 +23,7 @@ config X86_64
 	def_bool y
 	depends on 64BIT
 	# Options that are inherently 64-bit kernel only:
-	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_SUPPORTS_INT128
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select HAVE_ARCH_SOFT_DIRTY
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index 7469d321f072..f65cfb48cfdd 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -17,8 +17,4 @@ static inline void arch_clear_hugepage_flags(struct page *page)
 {
 }
 
-#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static inline bool gigantic_page_supported(void) { return true; }
-#endif
-
 #endif /* _ASM_X86_HUGETLB_H */
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 1f1ad9aeebb9..58ea44bf75de 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -589,8 +589,8 @@ static inline bool pm_suspended_storage(void)
 /* The below functions must be run on a range from a single zone. */
 extern int alloc_contig_range(unsigned long start, unsigned long end,
 			      unsigned migratetype, gfp_t gfp_mask);
-extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
 #endif
+extern void free_contig_range(unsigned long pfn, unsigned int nr_pages);
 
 #ifdef CONFIG_CMA
 /* CMA stuff */
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index afef61656c1e..9fc96ef5aa78 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1058,6 +1058,7 @@ static void free_gigantic_page(struct page *page, unsigned int order)
 	free_contig_range(page_to_pfn(page), 1 << order);
 }
 
+#ifdef CONFIG_CONTIG_ALLOC
 static int __alloc_gigantic_page(unsigned long start_pfn,
 				unsigned long nr_pages, gfp_t gfp_mask)
 {
@@ -1142,11 +1143,20 @@ static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
 
 static void prep_new_huge_page(struct hstate *h, struct page *page, int nid);
 static void prep_compound_gigantic_page(struct page *page, unsigned int order);
+#else /* !CONFIG_CONTIG_ALLOC */
+static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
+					int nid, nodemask_t *nodemask)
+{
+	return NULL;
+}
+#endif /* CONFIG_CONTIG_ALLOC */
 
 #else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */
-static inline bool gigantic_page_supported(void) { return false; }
 static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
-		int nid, nodemask_t *nodemask) { return NULL; }
+					int nid, nodemask_t *nodemask)
+{
+	return NULL;
+}
 static inline void free_gigantic_page(struct page *page, unsigned int order) { }
 static inline void destroy_compound_gigantic_page(struct page *page,
 						unsigned int order) { }
@@ -1156,9 +1166,6 @@ static void update_and_free_page(struct hstate *h, struct page *page)
 {
 	int i;
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported())
-		return;
-
 	h->nr_huge_pages--;
 	h->nr_huge_pages_node[page_to_nid(page)]--;
 	for (i = 0; i < pages_per_huge_page(h); i++) {
@@ -2276,13 +2283,27 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed,
 }
 
 #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages)
-static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
-						nodemask_t *nodes_allowed)
+static int set_max_huge_pages(struct hstate *h, unsigned long count,
+			      nodemask_t *nodes_allowed)
 {
 	unsigned long min_count, ret;
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported())
-		return h->max_huge_pages;
+	spin_lock(&hugetlb_lock);
+
+	/*
+	 * Gigantic pages runtime allocation depend on the capability for large
+	 * page range allocation.
+	 * If the system does not provide this feature, return an error when
+	 * the user tries to allocate gigantic pages but let the user free the
+	 * boottime allocated gigantic pages.
+	 */
+	if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) {
+		if (count > persistent_huge_pages(h)) {
+			spin_unlock(&hugetlb_lock);
+			return -EINVAL;
+		}
+		/* Fall through to decrease pool */
+	}
 
 	/*
 	 * Increase the pool size
@@ -2295,7 +2316,6 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 	 * pool might be one hugepage larger than it needs to be, but
 	 * within all the constraints specified by the sysctls.
 	 */
-	spin_lock(&hugetlb_lock);
 	while (h->surplus_huge_pages && count > persistent_huge_pages(h)) {
 		if (!adjust_pool_surplus(h, nodes_allowed, -1))
 			break;
@@ -2350,9 +2370,10 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 			break;
 	}
 out:
-	ret = persistent_huge_pages(h);
+	h->max_huge_pages = persistent_huge_pages(h);
 	spin_unlock(&hugetlb_lock);
-	return ret;
+
+	return 0;
 }
 
 #define HSTATE_ATTR_RO(_name) \
@@ -2404,11 +2425,6 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
 	int err;
 	NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY);
 
-	if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
-		err = -EINVAL;
-		goto out;
-	}
-
 	if (nid == NUMA_NO_NODE) {
 		/*
 		 * global hstate attribute
@@ -2428,15 +2444,12 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
 	} else
 		nodes_allowed = &node_states[N_MEMORY];
 
-	h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed);
+	err = set_max_huge_pages(h, count, nodes_allowed);
 
 	if (nodes_allowed != &node_states[N_MEMORY])
 		NODEMASK_FREE(nodes_allowed);
 
-	return len;
-out:
-	NODEMASK_FREE(nodes_allowed);
-	return err;
+	return err ? err : len;
 }
 
 static ssize_t nr_hugepages_store_common(bool obey_mempolicy,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ac9c45ffb344..a4547d90fa7a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8234,8 +8234,9 @@ int alloc_contig_range(unsigned long start, unsigned long end,
 				pfn_max_align_up(end), migratetype);
 	return ret;
 }
+#endif /* CONFIG_CONTIG_ALLOC */
 
-void free_contig_range(unsigned long pfn, unsigned nr_pages)
+void free_contig_range(unsigned long pfn, unsigned int nr_pages)
 {
 	unsigned int count = 0;
 
@@ -8247,7 +8248,6 @@ void free_contig_range(unsigned long pfn, unsigned nr_pages)
 	}
 	WARN(count != 0, "%d pages are still in use!\n", count);
 }
-#endif
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 /*
-- 
2.20.1


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Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Mike Kravetz]

On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
> On systems without CONTIG_ALLOC activated but that support gigantic pages,
> boottime reserved gigantic pages can not be freed at all. This patch
> simply enables the possibility to hand back those pages to memory
> allocator.
> 
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: David S. Miller <davem@davemloft.net> [sparc]

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>

-- 
Mike Kravetz

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Mike Kravetz]

On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
> On systems without CONTIG_ALLOC activated but that support gigantic pages,
> boottime reserved gigantic pages can not be freed at all. This patch
> simply enables the possibility to hand back those pages to memory
> allocator.
> 
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: David S. Miller <davem@davemloft.net> [sparc]

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>

-- 
Mike Kravetz

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Mike Kravetz]

On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
> On systems without CONTIG_ALLOC activated but that support gigantic pages,
> boottime reserved gigantic pages can not be freed at all. This patch
> simply enables the possibility to hand back those pages to memory
> allocator.
> 
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: David S. Miller <davem@davemloft.net> [sparc]

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>

-- 
Mike Kravetz

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Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alex Ghiti]

On 3/8/19 2:05 PM, Mike Kravetz wrote:
> On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
>> On systems without CONTIG_ALLOC activated but that support gigantic pages,
>> boottime reserved gigantic pages can not be freed at all. This patch
>> simply enables the possibility to hand back those pages to memory
>> allocator.
>>
>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Thanks Mike,

Alex

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alex Ghiti]

On 3/8/19 2:05 PM, Mike Kravetz wrote:
> On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
>> On systems without CONTIG_ALLOC activated but that support gigantic pages,
>> boottime reserved gigantic pages can not be freed at all. This patch
>> simply enables the possibility to hand back those pages to memory
>> allocator.
>>
>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Thanks Mike,

Alex

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alex Ghiti]

On 3/8/19 2:05 PM, Mike Kravetz wrote:
> On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
>> On systems without CONTIG_ALLOC activated but that support gigantic pages,
>> boottime reserved gigantic pages can not be freed at all. This patch
>> simply enables the possibility to hand back those pages to memory
>> allocator.
>>
>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Thanks Mike,

Alex

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Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alex Ghiti]

On 3/8/19 2:05 PM, Mike Kravetz wrote:
> On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
>> On systems without CONTIG_ALLOC activated but that support gigantic pages,
>> boottime reserved gigantic pages can not be freed at all. This patch
>> simply enables the possibility to hand back those pages to memory
>> allocator.
>>
>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Thanks Mike,

Alex

Re: [PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Dave Hansen]

On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
> This series fixes sh and sparc that did not advertise their gigantic page
> support and then were not able to allocate and free those pages at runtime.
> It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
> accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
> function.
> Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
> that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
> architectures to free boottime allocated gigantic pages although unrelated.

Looks good, thanks for all the changes.  For everything generic in the
set, plus the x86 bits:

Acked-by: Dave Hansen <dave.hansen@intel.com>

Re: [PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Dave Hansen]

On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
> This series fixes sh and sparc that did not advertise their gigantic page
> support and then were not able to allocate and free those pages at runtime.
> It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
> accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
> function.
> Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
> that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
> architectures to free boottime allocated gigantic pages although unrelated.

Looks good, thanks for all the changes.  For everything generic in the
set, plus the x86 bits:

Acked-by: Dave Hansen <dave.hansen@intel.com>

Re: [PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Dave Hansen]

On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
> This series fixes sh and sparc that did not advertise their gigantic page
> support and then were not able to allocate and free those pages at runtime.
> It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
> accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
> function.
> Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
> that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
> architectures to free boottime allocated gigantic pages although unrelated.

Looks good, thanks for all the changes.  For everything generic in the
set, plus the x86 bits:

Acked-by: Dave Hansen <dave.hansen@intel.com>

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Re: [PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Alexandre Ghiti]

On 03/13/2019 05:41 PM, Dave Hansen wrote:
> On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
>> This series fixes sh and sparc that did not advertise their gigantic page
>> support and then were not able to allocate and free those pages at runtime.
>> It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
>> accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
>> function.
>> Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
>> that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
>> architectures to free boottime allocated gigantic pages although unrelated.
> Looks good, thanks for all the changes.  For everything generic in the
> set, plus the x86 bits:
>
> Acked-by: Dave Hansen <dave.hansen@intel.com>

Thanks Dave,

Alex

Re: [PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Alexandre Ghiti]

On 03/13/2019 05:41 PM, Dave Hansen wrote:
> On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
>> This series fixes sh and sparc that did not advertise their gigantic page
>> support and then were not able to allocate and free those pages at runtime.
>> It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
>> accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
>> function.
>> Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
>> that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
>> architectures to free boottime allocated gigantic pages although unrelated.
> Looks good, thanks for all the changes.  For everything generic in the
> set, plus the x86 bits:
>
> Acked-by: Dave Hansen <dave.hansen@intel.com>

Thanks Dave,

Alex

Re: [PATCH v6 0/4] Fix free/allocation of runtime gigantic pages

[Alexandre Ghiti]

On 03/13/2019 05:41 PM, Dave Hansen wrote:
> On 3/7/19 5:20 AM, Alexandre Ghiti wrote:
>> This series fixes sh and sparc that did not advertise their gigantic page
>> support and then were not able to allocate and free those pages at runtime.
>> It renames MEMORY_ISOLATION && COMPACTION || CMA condition into the more
>> accurate CONTIG_ALLOC, since it allows the definition of alloc_contig_range
>> function.
>> Finally, it then fixes the wrong definition of ARCH_HAS_GIGANTIC_PAGE config
>> that, without MEMORY_ISOLATION && COMPACTION || CMA defined, did not allow
>> architectures to free boottime allocated gigantic pages although unrelated.
> Looks good, thanks for all the changes.  For everything generic in the
> set, plus the x86 bits:
>
> Acked-by: Dave Hansen <dave.hansen@intel.com>

Thanks Dave,

Alex

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Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Michael Ellerman]

[ Cc += Aneesh ]

Alexandre Ghiti <alex@ghiti.fr> writes:
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index 5b0177733994..d04a0bcc2f1c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>  	}
>  }
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void)
> -{
> -	return true;
> -}
> -#endif

This is going to clash with:

  https://patchwork.ozlabs.org/patch/1047003/

Which does:

@@ -35,6 +35,13 @@  static inline int hstate_get_psize(struct hstate *hstate)
 #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
 static inline bool gigantic_page_supported(void)
 {
+	/*
+	 * We used gigantic page reservation with hypervisor assist in some case.
+	 * We cannot use runtime allocation of gigantic pages in those platforms
+	 * This is hash translation mode LPARs.
+	 */
+	if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+		return false;
 	return true;
 }
 #endif


Not sure how to resolve it.

cheers

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Michael Ellerman]

[ Cc += Aneesh ]

Alexandre Ghiti <alex@ghiti.fr> writes:
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index 5b0177733994..d04a0bcc2f1c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>  	}
>  }
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void)
> -{
> -	return true;
> -}
> -#endif

This is going to clash with:

  https://patchwork.ozlabs.org/patch/1047003/

Which does:

@@ -35,6 +35,13 @@  static inline int hstate_get_psize(struct hstate *hstate)
 #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
 static inline bool gigantic_page_supported(void)
 {
+	/*
+	 * We used gigantic page reservation with hypervisor assist in some case.
+	 * We cannot use runtime allocation of gigantic pages in those platforms
+	 * This is hash translation mode LPARs.
+	 */
+	if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+		return false;
 	return true;
 }
 #endif


Not sure how to resolve it.

cheers

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Michael Ellerman]

[ Cc += Aneesh ]

Alexandre Ghiti <alex@ghiti.fr> writes:
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index 5b0177733994..d04a0bcc2f1c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>  	}
>  }
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void)
> -{
> -	return true;
> -}
> -#endif

This is going to clash with:

  https://patchwork.ozlabs.org/patch/1047003/

Which does:

@@ -35,6 +35,13 @@  static inline int hstate_get_psize(struct hstate *hstate)
 #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
 static inline bool gigantic_page_supported(void)
 {
+	/*
+	 * We used gigantic page reservation with hypervisor assist in some case.
+	 * We cannot use runtime allocation of gigantic pages in those platforms
+	 * This is hash translation mode LPARs.
+	 */
+	if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+		return false;
 	return true;
 }
 #endif


Not sure how to resolve it.

cheers

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Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Michael Ellerman]

[ Cc += Aneesh ]

Alexandre Ghiti <alex@ghiti.fr> writes:
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index 5b0177733994..d04a0bcc2f1c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>  	}
>  }
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void)
> -{
> -	return true;
> -}
> -#endif

This is going to clash with:

  https://patchwork.ozlabs.org/patch/1047003/

Which does:

@@ -35,6 +35,13 @@  static inline int hstate_get_psize(struct hstate *hstate)
 #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
 static inline bool gigantic_page_supported(void)
 {
+	/*
+	 * We used gigantic page reservation with hypervisor assist in some case.
+	 * We cannot use runtime allocation of gigantic pages in those platforms
+	 * This is hash translation mode LPARs.
+	 */
+	if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+		return false;
 	return true;
 }
 #endif


Not sure how to resolve it.

cheers

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Re: [PATCH v6 3/4] mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC

[Aneesh Kumar K.V]

Alexandre Ghiti <alex@ghiti.fr> writes:

> This condition allows to define alloc_contig_range, so simplify
> it into a more accurate naming.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>

>
> Suggested-by: Vlastimil Babka <vbabka@suse.cz>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: Vlastimil Babka <vbabka@suse.cz>
> ---
>  arch/arm64/Kconfig                     | 2 +-
>  arch/powerpc/platforms/Kconfig.cputype | 2 +-
>  arch/s390/Kconfig                      | 2 +-
>  arch/sh/Kconfig                        | 2 +-
>  arch/sparc/Kconfig                     | 2 +-
>  arch/x86/Kconfig                       | 2 +-
>  arch/x86/mm/hugetlbpage.c              | 2 +-
>  include/linux/gfp.h                    | 2 +-
>  mm/Kconfig                             | 3 +++
>  mm/page_alloc.c                        | 3 +--
>  10 files changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index a4168d366127..091a513b93e9 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -18,7 +18,7 @@ config ARM64
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>  	select ARCH_HAS_PTE_SPECIAL
> diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
> index 8c7464c3f27f..f677c8974212 100644
> --- a/arch/powerpc/platforms/Kconfig.cputype
> +++ b/arch/powerpc/platforms/Kconfig.cputype
> @@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
>  config PPC_RADIX_MMU
>  	bool "Radix MMU Support"
>  	depends on PPC_BOOK3S_64
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	default y
>  	help
>  	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index ed554b09eb3f..1c57b83c76f5 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -69,7 +69,7 @@ config S390
>  	select ARCH_HAS_ELF_RANDOMIZE
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_PTE_SPECIAL
>  	select ARCH_HAS_SET_MEMORY
> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> index 299a17bed67c..c7266302691c 100644
> --- a/arch/sh/Kconfig
> +++ b/arch/sh/Kconfig
> @@ -53,7 +53,7 @@ config SUPERH
>  	select HAVE_FUTEX_CMPXCHG if FUTEX
>  	select HAVE_NMI
>  	select NEED_SG_DMA_LENGTH
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  
>  	help
>  	  The SuperH is a RISC processor targeted for use in embedded systems
> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
> index 0b7f0e0fefa5..ca33c80870e2 100644
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -90,7 +90,7 @@ config SPARC64
>  	select ARCH_CLOCKSOURCE_DATA
>  	select ARCH_HAS_PTE_SPECIAL
>  	select PCI_DOMAINS if PCI
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  
>  config ARCH_DEFCONFIG
>  	string
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 68261430fe6e..8ba90f3e0038 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -23,7 +23,7 @@ config X86_64
>  	def_bool y
>  	depends on 64BIT
>  	# Options that are inherently 64-bit kernel only:
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_SUPPORTS_INT128
>  	select ARCH_USE_CMPXCHG_LOCKREF
>  	select HAVE_ARCH_SOFT_DIRTY
> diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
> index 92e4c4b85bba..fab095362c50 100644
> --- a/arch/x86/mm/hugetlbpage.c
> +++ b/arch/x86/mm/hugetlbpage.c
> @@ -203,7 +203,7 @@ static __init int setup_hugepagesz(char *opt)
>  }
>  __setup("hugepagesz=", setup_hugepagesz);
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> +#ifdef CONFIG_CONTIG_ALLOC
>  static __init int gigantic_pages_init(void)
>  {
>  	/* With compaction or CMA we can allocate gigantic pages at runtime */
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index 5f5e25fd6149..1f1ad9aeebb9 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -585,7 +585,7 @@ static inline bool pm_suspended_storage(void)
>  }
>  #endif /* CONFIG_PM_SLEEP */
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> +#ifdef CONFIG_CONTIG_ALLOC
>  /* The below functions must be run on a range from a single zone. */
>  extern int alloc_contig_range(unsigned long start, unsigned long end,
>  			      unsigned migratetype, gfp_t gfp_mask);
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 25c71eb8a7db..137eadc18732 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -258,6 +258,9 @@ config ARCH_ENABLE_HUGEPAGE_MIGRATION
>  config ARCH_ENABLE_THP_MIGRATION
>  	bool
>  
> +config CONTIG_ALLOC
> +       def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
> +
>  config PHYS_ADDR_T_64BIT
>  	def_bool 64BIT
>  
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 35fdde041f5c..ac9c45ffb344 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -8024,8 +8024,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
>  	return true;
>  }
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> -
> +#ifdef CONFIG_CONTIG_ALLOC
>  static unsigned long pfn_max_align_down(unsigned long pfn)
>  {
>  	return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
> -- 
> 2.20.1

Re: [PATCH v6 3/4] mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC

[Aneesh Kumar K.V]

Alexandre Ghiti <alex@ghiti.fr> writes:

> This condition allows to define alloc_contig_range, so simplify
> it into a more accurate naming.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>

>
> Suggested-by: Vlastimil Babka <vbabka@suse.cz>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: Vlastimil Babka <vbabka@suse.cz>
> ---
>  arch/arm64/Kconfig                     | 2 +-
>  arch/powerpc/platforms/Kconfig.cputype | 2 +-
>  arch/s390/Kconfig                      | 2 +-
>  arch/sh/Kconfig                        | 2 +-
>  arch/sparc/Kconfig                     | 2 +-
>  arch/x86/Kconfig                       | 2 +-
>  arch/x86/mm/hugetlbpage.c              | 2 +-
>  include/linux/gfp.h                    | 2 +-
>  mm/Kconfig                             | 3 +++
>  mm/page_alloc.c                        | 3 +--
>  10 files changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index a4168d366127..091a513b93e9 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -18,7 +18,7 @@ config ARM64
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>  	select ARCH_HAS_PTE_SPECIAL
> diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
> index 8c7464c3f27f..f677c8974212 100644
> --- a/arch/powerpc/platforms/Kconfig.cputype
> +++ b/arch/powerpc/platforms/Kconfig.cputype
> @@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
>  config PPC_RADIX_MMU
>  	bool "Radix MMU Support"
>  	depends on PPC_BOOK3S_64
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	default y
>  	help
>  	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index ed554b09eb3f..1c57b83c76f5 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -69,7 +69,7 @@ config S390
>  	select ARCH_HAS_ELF_RANDOMIZE
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_PTE_SPECIAL
>  	select ARCH_HAS_SET_MEMORY
> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> index 299a17bed67c..c7266302691c 100644
> --- a/arch/sh/Kconfig
> +++ b/arch/sh/Kconfig
> @@ -53,7 +53,7 @@ config SUPERH
>  	select HAVE_FUTEX_CMPXCHG if FUTEX
>  	select HAVE_NMI
>  	select NEED_SG_DMA_LENGTH
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  
>  	help
>  	  The SuperH is a RISC processor targeted for use in embedded systems
> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
> index 0b7f0e0fefa5..ca33c80870e2 100644
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -90,7 +90,7 @@ config SPARC64
>  	select ARCH_CLOCKSOURCE_DATA
>  	select ARCH_HAS_PTE_SPECIAL
>  	select PCI_DOMAINS if PCI
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  
>  config ARCH_DEFCONFIG
>  	string
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 68261430fe6e..8ba90f3e0038 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -23,7 +23,7 @@ config X86_64
>  	def_bool y
>  	depends on 64BIT
>  	# Options that are inherently 64-bit kernel only:
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_SUPPORTS_INT128
>  	select ARCH_USE_CMPXCHG_LOCKREF
>  	select HAVE_ARCH_SOFT_DIRTY
> diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
> index 92e4c4b85bba..fab095362c50 100644
> --- a/arch/x86/mm/hugetlbpage.c
> +++ b/arch/x86/mm/hugetlbpage.c
> @@ -203,7 +203,7 @@ static __init int setup_hugepagesz(char *opt)
>  }
>  __setup("hugepagesz=", setup_hugepagesz);
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> +#ifdef CONFIG_CONTIG_ALLOC
>  static __init int gigantic_pages_init(void)
>  {
>  	/* With compaction or CMA we can allocate gigantic pages at runtime */
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index 5f5e25fd6149..1f1ad9aeebb9 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -585,7 +585,7 @@ static inline bool pm_suspended_storage(void)
>  }
>  #endif /* CONFIG_PM_SLEEP */
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> +#ifdef CONFIG_CONTIG_ALLOC
>  /* The below functions must be run on a range from a single zone. */
>  extern int alloc_contig_range(unsigned long start, unsigned long end,
>  			      unsigned migratetype, gfp_t gfp_mask);
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 25c71eb8a7db..137eadc18732 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -258,6 +258,9 @@ config ARCH_ENABLE_HUGEPAGE_MIGRATION
>  config ARCH_ENABLE_THP_MIGRATION
>  	bool
>  
> +config CONTIG_ALLOC
> +       def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
> +
>  config PHYS_ADDR_T_64BIT
>  	def_bool 64BIT
>  
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 35fdde041f5c..ac9c45ffb344 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -8024,8 +8024,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
>  	return true;
>  }
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> -
> +#ifdef CONFIG_CONTIG_ALLOC
>  static unsigned long pfn_max_align_down(unsigned long pfn)
>  {
>  	return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
> -- 
> 2.20.1


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Re: [PATCH v6 3/4] mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC

[Aneesh Kumar K.V]

Alexandre Ghiti <alex@ghiti.fr> writes:

> This condition allows to define alloc_contig_range, so simplify
> it into a more accurate naming.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>

>
> Suggested-by: Vlastimil Babka <vbabka@suse.cz>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: Vlastimil Babka <vbabka@suse.cz>
> ---
>  arch/arm64/Kconfig                     | 2 +-
>  arch/powerpc/platforms/Kconfig.cputype | 2 +-
>  arch/s390/Kconfig                      | 2 +-
>  arch/sh/Kconfig                        | 2 +-
>  arch/sparc/Kconfig                     | 2 +-
>  arch/x86/Kconfig                       | 2 +-
>  arch/x86/mm/hugetlbpage.c              | 2 +-
>  include/linux/gfp.h                    | 2 +-
>  mm/Kconfig                             | 3 +++
>  mm/page_alloc.c                        | 3 +--
>  10 files changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index a4168d366127..091a513b93e9 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -18,7 +18,7 @@ config ARM64
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>  	select ARCH_HAS_PTE_SPECIAL
> diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
> index 8c7464c3f27f..f677c8974212 100644
> --- a/arch/powerpc/platforms/Kconfig.cputype
> +++ b/arch/powerpc/platforms/Kconfig.cputype
> @@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
>  config PPC_RADIX_MMU
>  	bool "Radix MMU Support"
>  	depends on PPC_BOOK3S_64
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	default y
>  	help
>  	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index ed554b09eb3f..1c57b83c76f5 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -69,7 +69,7 @@ config S390
>  	select ARCH_HAS_ELF_RANDOMIZE
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_PTE_SPECIAL
>  	select ARCH_HAS_SET_MEMORY
> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> index 299a17bed67c..c7266302691c 100644
> --- a/arch/sh/Kconfig
> +++ b/arch/sh/Kconfig
> @@ -53,7 +53,7 @@ config SUPERH
>  	select HAVE_FUTEX_CMPXCHG if FUTEX
>  	select HAVE_NMI
>  	select NEED_SG_DMA_LENGTH
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  
>  	help
>  	  The SuperH is a RISC processor targeted for use in embedded systems
> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
> index 0b7f0e0fefa5..ca33c80870e2 100644
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -90,7 +90,7 @@ config SPARC64
>  	select ARCH_CLOCKSOURCE_DATA
>  	select ARCH_HAS_PTE_SPECIAL
>  	select PCI_DOMAINS if PCI
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  
>  config ARCH_DEFCONFIG
>  	string
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 68261430fe6e..8ba90f3e0038 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -23,7 +23,7 @@ config X86_64
>  	def_bool y
>  	depends on 64BIT
>  	# Options that are inherently 64-bit kernel only:
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_SUPPORTS_INT128
>  	select ARCH_USE_CMPXCHG_LOCKREF
>  	select HAVE_ARCH_SOFT_DIRTY
> diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
> index 92e4c4b85bba..fab095362c50 100644
> --- a/arch/x86/mm/hugetlbpage.c
> +++ b/arch/x86/mm/hugetlbpage.c
> @@ -203,7 +203,7 @@ static __init int setup_hugepagesz(char *opt)
>  }
>  __setup("hugepagesz=", setup_hugepagesz);
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> +#ifdef CONFIG_CONTIG_ALLOC
>  static __init int gigantic_pages_init(void)
>  {
>  	/* With compaction or CMA we can allocate gigantic pages at runtime */
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index 5f5e25fd6149..1f1ad9aeebb9 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -585,7 +585,7 @@ static inline bool pm_suspended_storage(void)
>  }
>  #endif /* CONFIG_PM_SLEEP */
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> +#ifdef CONFIG_CONTIG_ALLOC
>  /* The below functions must be run on a range from a single zone. */
>  extern int alloc_contig_range(unsigned long start, unsigned long end,
>  			      unsigned migratetype, gfp_t gfp_mask);
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 25c71eb8a7db..137eadc18732 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -258,6 +258,9 @@ config ARCH_ENABLE_HUGEPAGE_MIGRATION
>  config ARCH_ENABLE_THP_MIGRATION
>  	bool
>  
> +config CONTIG_ALLOC
> +       def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
> +
>  config PHYS_ADDR_T_64BIT
>  	def_bool 64BIT
>  
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 35fdde041f5c..ac9c45ffb344 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -8024,8 +8024,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
>  	return true;
>  }
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> -
> +#ifdef CONFIG_CONTIG_ALLOC
>  static unsigned long pfn_max_align_down(unsigned long pfn)
>  {
>  	return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
> -- 
> 2.20.1


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Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

Alexandre Ghiti <alex@ghiti.fr> writes:

> On systems without CONTIG_ALLOC activated but that support gigantic pages,
> boottime reserved gigantic pages can not be freed at all. This patch
> simply enables the possibility to hand back those pages to memory
> allocator.
>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
> ---
>  arch/arm64/Kconfig                           |  2 +-
>  arch/arm64/include/asm/hugetlb.h             |  4 --
>  arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>  arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>  arch/s390/Kconfig                            |  2 +-
>  arch/s390/include/asm/hugetlb.h              |  3 --
>  arch/sh/Kconfig                              |  2 +-
>  arch/sparc/Kconfig                           |  2 +-
>  arch/x86/Kconfig                             |  2 +-
>  arch/x86/include/asm/hugetlb.h               |  4 --
>  include/linux/gfp.h                          |  2 +-
>  mm/hugetlb.c                                 | 57 ++++++++++++--------
>  mm/page_alloc.c                              |  4 +-
>  13 files changed, 44 insertions(+), 49 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 091a513b93e9..af687eff884a 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -18,7 +18,7 @@ config ARM64
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
> +	select ARCH_HAS_GIGANTIC_PAGE
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>  	select ARCH_HAS_PTE_SPECIAL
> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
> index fb6609875455..59893e766824 100644
> --- a/arch/arm64/include/asm/hugetlb.h
> +++ b/arch/arm64/include/asm/hugetlb.h
> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
>  
>  #include <asm-generic/hugetlb.h>
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void) { return true; }
> -#endif
> -
>  #endif /* __ASM_HUGETLB_H */
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index 5b0177733994..d04a0bcc2f1c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>  	}
>  }
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void)
> -{
> -	return true;
> -}
> -#endif
> -
>  /* hugepd entry valid bit */
>  #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
>  

As explained in https://patchwork.ozlabs.org/patch/1047003/
architectures like ppc64 have a hypervisor assisted mechanism to indicate
where to find gigantic huge pages(16G pages). At this point, we don't use this
reserved pages for anything other than hugetlb backing and hence there
is no runtime free of this pages needed ( Also we don't do
runtime allocation of them).

I guess you can still achieve what you want to do in this patch by
keeping gigantic_page_supported()?

NOTE: We should rename gigantic_page_supported to be more specific to
support for runtime_alloc/free of gigantic pages

-aneesh

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

Alexandre Ghiti <alex@ghiti.fr> writes:

> On systems without CONTIG_ALLOC activated but that support gigantic pages,
> boottime reserved gigantic pages can not be freed at all. This patch
> simply enables the possibility to hand back those pages to memory
> allocator.
>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
> ---
>  arch/arm64/Kconfig                           |  2 +-
>  arch/arm64/include/asm/hugetlb.h             |  4 --
>  arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>  arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>  arch/s390/Kconfig                            |  2 +-
>  arch/s390/include/asm/hugetlb.h              |  3 --
>  arch/sh/Kconfig                              |  2 +-
>  arch/sparc/Kconfig                           |  2 +-
>  arch/x86/Kconfig                             |  2 +-
>  arch/x86/include/asm/hugetlb.h               |  4 --
>  include/linux/gfp.h                          |  2 +-
>  mm/hugetlb.c                                 | 57 ++++++++++++--------
>  mm/page_alloc.c                              |  4 +-
>  13 files changed, 44 insertions(+), 49 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 091a513b93e9..af687eff884a 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -18,7 +18,7 @@ config ARM64
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
> +	select ARCH_HAS_GIGANTIC_PAGE
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>  	select ARCH_HAS_PTE_SPECIAL
> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
> index fb6609875455..59893e766824 100644
> --- a/arch/arm64/include/asm/hugetlb.h
> +++ b/arch/arm64/include/asm/hugetlb.h
> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
>  
>  #include <asm-generic/hugetlb.h>
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void) { return true; }
> -#endif
> -
>  #endif /* __ASM_HUGETLB_H */
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index 5b0177733994..d04a0bcc2f1c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>  	}
>  }
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void)
> -{
> -	return true;
> -}
> -#endif
> -
>  /* hugepd entry valid bit */
>  #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
>  

As explained in https://patchwork.ozlabs.org/patch/1047003/
architectures like ppc64 have a hypervisor assisted mechanism to indicate
where to find gigantic huge pages(16G pages). At this point, we don't use this
reserved pages for anything other than hugetlb backing and hence there
is no runtime free of this pages needed ( Also we don't do
runtime allocation of them).

I guess you can still achieve what you want to do in this patch by
keeping gigantic_page_supported()?

NOTE: We should rename gigantic_page_supported to be more specific to
support for runtime_alloc/free of gigantic pages

-aneesh


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

Alexandre Ghiti <alex@ghiti.fr> writes:

> On systems without CONTIG_ALLOC activated but that support gigantic pages,
> boottime reserved gigantic pages can not be freed at all. This patch
> simply enables the possibility to hand back those pages to memory
> allocator.
>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
> ---
>  arch/arm64/Kconfig                           |  2 +-
>  arch/arm64/include/asm/hugetlb.h             |  4 --
>  arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>  arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>  arch/s390/Kconfig                            |  2 +-
>  arch/s390/include/asm/hugetlb.h              |  3 --
>  arch/sh/Kconfig                              |  2 +-
>  arch/sparc/Kconfig                           |  2 +-
>  arch/x86/Kconfig                             |  2 +-
>  arch/x86/include/asm/hugetlb.h               |  4 --
>  include/linux/gfp.h                          |  2 +-
>  mm/hugetlb.c                                 | 57 ++++++++++++--------
>  mm/page_alloc.c                              |  4 +-
>  13 files changed, 44 insertions(+), 49 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 091a513b93e9..af687eff884a 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -18,7 +18,7 @@ config ARM64
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
> +	select ARCH_HAS_GIGANTIC_PAGE
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>  	select ARCH_HAS_PTE_SPECIAL
> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
> index fb6609875455..59893e766824 100644
> --- a/arch/arm64/include/asm/hugetlb.h
> +++ b/arch/arm64/include/asm/hugetlb.h
> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
>  
>  #include <asm-generic/hugetlb.h>
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void) { return true; }
> -#endif
> -
>  #endif /* __ASM_HUGETLB_H */
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index 5b0177733994..d04a0bcc2f1c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>  	}
>  }
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void)
> -{
> -	return true;
> -}
> -#endif
> -
>  /* hugepd entry valid bit */
>  #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
>  

As explained in https://patchwork.ozlabs.org/patch/1047003/
architectures like ppc64 have a hypervisor assisted mechanism to indicate
where to find gigantic huge pages(16G pages). At this point, we don't use this
reserved pages for anything other than hugetlb backing and hence there
is no runtime free of this pages needed ( Also we don't do
runtime allocation of them).

I guess you can still achieve what you want to do in this patch by
keeping gigantic_page_supported()?

NOTE: We should rename gigantic_page_supported to be more specific to
support for runtime_alloc/free of gigantic pages

-aneesh


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

Alexandre Ghiti <alex@ghiti.fr> writes:

> On systems without CONTIG_ALLOC activated but that support gigantic pages,
> boottime reserved gigantic pages can not be freed at all. This patch
> simply enables the possibility to hand back those pages to memory
> allocator.
>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
> ---
>  arch/arm64/Kconfig                           |  2 +-
>  arch/arm64/include/asm/hugetlb.h             |  4 --
>  arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>  arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>  arch/s390/Kconfig                            |  2 +-
>  arch/s390/include/asm/hugetlb.h              |  3 --
>  arch/sh/Kconfig                              |  2 +-
>  arch/sparc/Kconfig                           |  2 +-
>  arch/x86/Kconfig                             |  2 +-
>  arch/x86/include/asm/hugetlb.h               |  4 --
>  include/linux/gfp.h                          |  2 +-
>  mm/hugetlb.c                                 | 57 ++++++++++++--------
>  mm/page_alloc.c                              |  4 +-
>  13 files changed, 44 insertions(+), 49 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 091a513b93e9..af687eff884a 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -18,7 +18,7 @@ config ARM64
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
> +	select ARCH_HAS_GIGANTIC_PAGE
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>  	select ARCH_HAS_PTE_SPECIAL
> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
> index fb6609875455..59893e766824 100644
> --- a/arch/arm64/include/asm/hugetlb.h
> +++ b/arch/arm64/include/asm/hugetlb.h
> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
>  
>  #include <asm-generic/hugetlb.h>
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void) { return true; }
> -#endif
> -
>  #endif /* __ASM_HUGETLB_H */
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index 5b0177733994..d04a0bcc2f1c 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>  	}
>  }
>  
> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> -static inline bool gigantic_page_supported(void)
> -{
> -	return true;
> -}
> -#endif
> -
>  /* hugepd entry valid bit */
>  #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
>  

As explained in https://patchwork.ozlabs.org/patch/1047003/
architectures like ppc64 have a hypervisor assisted mechanism to indicate
where to find gigantic huge pages(16G pages). At this point, we don't use this
reserved pages for anything other than hugetlb backing and hence there
is no runtime free of this pages needed ( Also we don't do
runtime allocation of them).

I guess you can still achieve what you want to do in this patch by
keeping gigantic_page_supported()?

NOTE: We should rename gigantic_page_supported to be more specific to
support for runtime_alloc/free of gigantic pages

-aneesh

Re: [PATCH v6 3/4] mm: Simplify MEMORY_ISOLATION && COMPACTION || CMA into CONTIG_ALLOC

[Aneesh Kumar K.V]

Alexandre Ghiti <alex@ghiti.fr> writes:

> This condition allows to define alloc_contig_range, so simplify
> it into a more accurate naming.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>

>
> Suggested-by: Vlastimil Babka <vbabka@suse.cz>
> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: Vlastimil Babka <vbabka@suse.cz>
> ---
>  arch/arm64/Kconfig                     | 2 +-
>  arch/powerpc/platforms/Kconfig.cputype | 2 +-
>  arch/s390/Kconfig                      | 2 +-
>  arch/sh/Kconfig                        | 2 +-
>  arch/sparc/Kconfig                     | 2 +-
>  arch/x86/Kconfig                       | 2 +-
>  arch/x86/mm/hugetlbpage.c              | 2 +-
>  include/linux/gfp.h                    | 2 +-
>  mm/Kconfig                             | 3 +++
>  mm/page_alloc.c                        | 3 +--
>  10 files changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index a4168d366127..091a513b93e9 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -18,7 +18,7 @@ config ARM64
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>  	select ARCH_HAS_PTE_SPECIAL
> diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
> index 8c7464c3f27f..f677c8974212 100644
> --- a/arch/powerpc/platforms/Kconfig.cputype
> +++ b/arch/powerpc/platforms/Kconfig.cputype
> @@ -319,7 +319,7 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK
>  config PPC_RADIX_MMU
>  	bool "Radix MMU Support"
>  	depends on PPC_BOOK3S_64
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	default y
>  	help
>  	  Enable support for the Power ISA 3.0 Radix style MMU. Currently this
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index ed554b09eb3f..1c57b83c76f5 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -69,7 +69,7 @@ config S390
>  	select ARCH_HAS_ELF_RANDOMIZE
>  	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_HAS_KCOV
>  	select ARCH_HAS_PTE_SPECIAL
>  	select ARCH_HAS_SET_MEMORY
> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> index 299a17bed67c..c7266302691c 100644
> --- a/arch/sh/Kconfig
> +++ b/arch/sh/Kconfig
> @@ -53,7 +53,7 @@ config SUPERH
>  	select HAVE_FUTEX_CMPXCHG if FUTEX
>  	select HAVE_NMI
>  	select NEED_SG_DMA_LENGTH
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  
>  	help
>  	  The SuperH is a RISC processor targeted for use in embedded systems
> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
> index 0b7f0e0fefa5..ca33c80870e2 100644
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -90,7 +90,7 @@ config SPARC64
>  	select ARCH_CLOCKSOURCE_DATA
>  	select ARCH_HAS_PTE_SPECIAL
>  	select PCI_DOMAINS if PCI
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  
>  config ARCH_DEFCONFIG
>  	string
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 68261430fe6e..8ba90f3e0038 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -23,7 +23,7 @@ config X86_64
>  	def_bool y
>  	depends on 64BIT
>  	# Options that are inherently 64-bit kernel only:
> -	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
> +	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>  	select ARCH_SUPPORTS_INT128
>  	select ARCH_USE_CMPXCHG_LOCKREF
>  	select HAVE_ARCH_SOFT_DIRTY
> diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
> index 92e4c4b85bba..fab095362c50 100644
> --- a/arch/x86/mm/hugetlbpage.c
> +++ b/arch/x86/mm/hugetlbpage.c
> @@ -203,7 +203,7 @@ static __init int setup_hugepagesz(char *opt)
>  }
>  __setup("hugepagesz=", setup_hugepagesz);
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> +#ifdef CONFIG_CONTIG_ALLOC
>  static __init int gigantic_pages_init(void)
>  {
>  	/* With compaction or CMA we can allocate gigantic pages at runtime */
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index 5f5e25fd6149..1f1ad9aeebb9 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -585,7 +585,7 @@ static inline bool pm_suspended_storage(void)
>  }
>  #endif /* CONFIG_PM_SLEEP */
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> +#ifdef CONFIG_CONTIG_ALLOC
>  /* The below functions must be run on a range from a single zone. */
>  extern int alloc_contig_range(unsigned long start, unsigned long end,
>  			      unsigned migratetype, gfp_t gfp_mask);
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 25c71eb8a7db..137eadc18732 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -258,6 +258,9 @@ config ARCH_ENABLE_HUGEPAGE_MIGRATION
>  config ARCH_ENABLE_THP_MIGRATION
>  	bool
>  
> +config CONTIG_ALLOC
> +       def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
> +
>  config PHYS_ADDR_T_64BIT
>  	def_bool 64BIT
>  
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 35fdde041f5c..ac9c45ffb344 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -8024,8 +8024,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
>  	return true;
>  }
>  
> -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
> -
> +#ifdef CONFIG_CONTIG_ALLOC
>  static unsigned long pfn_max_align_down(unsigned long pfn)
>  {
>  	return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
> -- 
> 2.20.1

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
> Alexandre Ghiti <alex@ghiti.fr> writes:
>
>> On systems without CONTIG_ALLOC activated but that support gigantic pages,
>> boottime reserved gigantic pages can not be freed at all. This patch
>> simply enables the possibility to hand back those pages to memory
>> allocator.
>>
>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>> ---
>>   arch/arm64/Kconfig                           |  2 +-
>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>   arch/s390/Kconfig                            |  2 +-
>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>   arch/sh/Kconfig                              |  2 +-
>>   arch/sparc/Kconfig                           |  2 +-
>>   arch/x86/Kconfig                             |  2 +-
>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>   include/linux/gfp.h                          |  2 +-
>>   mm/hugetlb.c                                 | 57 ++++++++++++--------
>>   mm/page_alloc.c                              |  4 +-
>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>
>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>> index 091a513b93e9..af687eff884a 100644
>> --- a/arch/arm64/Kconfig
>> +++ b/arch/arm64/Kconfig
>> @@ -18,7 +18,7 @@ config ARM64
>>   	select ARCH_HAS_FAST_MULTIPLIER
>>   	select ARCH_HAS_FORTIFY_SOURCE
>>   	select ARCH_HAS_GCOV_PROFILE_ALL
>> -	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>> +	select ARCH_HAS_GIGANTIC_PAGE
>>   	select ARCH_HAS_KCOV
>>   	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>   	select ARCH_HAS_PTE_SPECIAL
>> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
>> index fb6609875455..59893e766824 100644
>> --- a/arch/arm64/include/asm/hugetlb.h
>> +++ b/arch/arm64/include/asm/hugetlb.h
>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
>>   
>>   #include <asm-generic/hugetlb.h>
>>   
>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> -static inline bool gigantic_page_supported(void) { return true; }
>> -#endif
>> -
>>   #endif /* __ASM_HUGETLB_H */
>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> index 5b0177733994..d04a0bcc2f1c 100644
>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>>   	}
>>   }
>>   
>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> -static inline bool gigantic_page_supported(void)
>> -{
>> -	return true;
>> -}
>> -#endif
>> -
>>   /* hugepd entry valid bit */
>>   #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
>>   
> As explained in https://patchwork.ozlabs.org/patch/1047003/
> architectures like ppc64 have a hypervisor assisted mechanism to indicate
> where to find gigantic huge pages(16G pages). At this point, we don't use this
> reserved pages for anything other than hugetlb backing and hence there
> is no runtime free of this pages needed ( Also we don't do
> runtime allocation of them).
>
> I guess you can still achieve what you want to do in this patch by
> keeping gigantic_page_supported()?
>
> NOTE: We should rename gigantic_page_supported to be more specific to
> support for runtime_alloc/free of gigantic pages
>
> -aneesh
>
Thanks for noticing Aneesh.

I can't find a better solution than bringing back 
gigantic_page_supported check,
since it is must be done at runtime in your case.
I'm not sure of one thing though: you say that freeing boottime gigantic 
pages
is not needed, but is it forbidden ? Just to know where the check and 
what its
new name should be.
Is something like that (on top of this series) ok for you (and everyone 
else) before
I send a v7:

diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
b/arch/powerpc/include/asm/book3s/64/hugetlb.h
index d04a0bc..d121559 100644
--- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
+++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
@@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate *hstate)
  /* hugepd entry valid bit */
  #define HUGEPD_VAL_BITS                (0x8000000000000000UL)

+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
+static inline bool gigantic_page_supported(void)
+{
+       /*
+        * We used gigantic page reservation with hypervisor assist in 
some case.
+        * We cannot use runtime allocation of gigantic pages in those 
platforms
+        * This is hash translation mode LPARs.
+        */
+       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+               return false;
+
+       return true;
+}
+#endif
+
  #endif
diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
index 71d7b77..7d12e73 100644
--- a/include/asm-generic/hugetlb.h
+++ b/include/asm-generic/hugetlb.h
@@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
  }
  #endif

+#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+static inline bool gigantic_page_supported(void)
+{
+        return true;
+}
+#else
+static inline bool gigantic_page_supported(void)
+{
+        return false;
+}
+#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
+#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
+
  #endif /* _ASM_GENERIC_HUGETLB_H */
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 9fc96ef..cfbbafe 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2425,6 +2425,11 @@ static ssize_t __nr_hugepages_store_common(bool 
obey_mempolicy,
         int err;
         NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
__GFP_NORETRY);

+       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
+               err = -EINVAL;
+               goto out;
+       }
+
         if (nid = NUMA_NO_NODE) {
                 /*
                  * global hstate attribute
@@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
obey_mempolicy,

         err = set_max_huge_pages(h, count, nodes_allowed);

+out:
         if (nodes_allowed != &node_states[N_MEMORY])
                 NODEMASK_FREE(nodes_allowed);

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
> Alexandre Ghiti <alex@ghiti.fr> writes:
>
>> On systems without CONTIG_ALLOC activated but that support gigantic pages,
>> boottime reserved gigantic pages can not be freed at all. This patch
>> simply enables the possibility to hand back those pages to memory
>> allocator.
>>
>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>> ---
>>   arch/arm64/Kconfig                           |  2 +-
>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>   arch/s390/Kconfig                            |  2 +-
>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>   arch/sh/Kconfig                              |  2 +-
>>   arch/sparc/Kconfig                           |  2 +-
>>   arch/x86/Kconfig                             |  2 +-
>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>   include/linux/gfp.h                          |  2 +-
>>   mm/hugetlb.c                                 | 57 ++++++++++++--------
>>   mm/page_alloc.c                              |  4 +-
>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>
>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>> index 091a513b93e9..af687eff884a 100644
>> --- a/arch/arm64/Kconfig
>> +++ b/arch/arm64/Kconfig
>> @@ -18,7 +18,7 @@ config ARM64
>>   	select ARCH_HAS_FAST_MULTIPLIER
>>   	select ARCH_HAS_FORTIFY_SOURCE
>>   	select ARCH_HAS_GCOV_PROFILE_ALL
>> -	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>> +	select ARCH_HAS_GIGANTIC_PAGE
>>   	select ARCH_HAS_KCOV
>>   	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>   	select ARCH_HAS_PTE_SPECIAL
>> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
>> index fb6609875455..59893e766824 100644
>> --- a/arch/arm64/include/asm/hugetlb.h
>> +++ b/arch/arm64/include/asm/hugetlb.h
>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
>>   
>>   #include <asm-generic/hugetlb.h>
>>   
>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> -static inline bool gigantic_page_supported(void) { return true; }
>> -#endif
>> -
>>   #endif /* __ASM_HUGETLB_H */
>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> index 5b0177733994..d04a0bcc2f1c 100644
>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>>   	}
>>   }
>>   
>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> -static inline bool gigantic_page_supported(void)
>> -{
>> -	return true;
>> -}
>> -#endif
>> -
>>   /* hugepd entry valid bit */
>>   #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
>>   
> As explained in https://patchwork.ozlabs.org/patch/1047003/
> architectures like ppc64 have a hypervisor assisted mechanism to indicate
> where to find gigantic huge pages(16G pages). At this point, we don't use this
> reserved pages for anything other than hugetlb backing and hence there
> is no runtime free of this pages needed ( Also we don't do
> runtime allocation of them).
>
> I guess you can still achieve what you want to do in this patch by
> keeping gigantic_page_supported()?
>
> NOTE: We should rename gigantic_page_supported to be more specific to
> support for runtime_alloc/free of gigantic pages
>
> -aneesh
>
Thanks for noticing Aneesh.

I can't find a better solution than bringing back 
gigantic_page_supported check,
since it is must be done at runtime in your case.
I'm not sure of one thing though: you say that freeing boottime gigantic 
pages
is not needed, but is it forbidden ? Just to know where the check and 
what its
new name should be.
Is something like that (on top of this series) ok for you (and everyone 
else) before
I send a v7:

diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
b/arch/powerpc/include/asm/book3s/64/hugetlb.h
index d04a0bc..d121559 100644
--- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
+++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
@@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate *hstate)
  /* hugepd entry valid bit */
  #define HUGEPD_VAL_BITS                (0x8000000000000000UL)

+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
+static inline bool gigantic_page_supported(void)
+{
+       /*
+        * We used gigantic page reservation with hypervisor assist in 
some case.
+        * We cannot use runtime allocation of gigantic pages in those 
platforms
+        * This is hash translation mode LPARs.
+        */
+       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+               return false;
+
+       return true;
+}
+#endif
+
  #endif
diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
index 71d7b77..7d12e73 100644
--- a/include/asm-generic/hugetlb.h
+++ b/include/asm-generic/hugetlb.h
@@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
  }
  #endif

+#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+static inline bool gigantic_page_supported(void)
+{
+        return true;
+}
+#else
+static inline bool gigantic_page_supported(void)
+{
+        return false;
+}
+#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
+#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
+
  #endif /* _ASM_GENERIC_HUGETLB_H */
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 9fc96ef..cfbbafe 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2425,6 +2425,11 @@ static ssize_t __nr_hugepages_store_common(bool 
obey_mempolicy,
         int err;
         NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
__GFP_NORETRY);

+       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
+               err = -EINVAL;
+               goto out;
+       }
+
         if (nid == NUMA_NO_NODE) {
                 /*
                  * global hstate attribute
@@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
obey_mempolicy,

         err = set_max_huge_pages(h, count, nodes_allowed);

+out:
         if (nodes_allowed != &node_states[N_MEMORY])
                 NODEMASK_FREE(nodes_allowed);

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
> Alexandre Ghiti <alex@ghiti.fr> writes:
>
>> On systems without CONTIG_ALLOC activated but that support gigantic pages,
>> boottime reserved gigantic pages can not be freed at all. This patch
>> simply enables the possibility to hand back those pages to memory
>> allocator.
>>
>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>> ---
>>   arch/arm64/Kconfig                           |  2 +-
>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>   arch/s390/Kconfig                            |  2 +-
>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>   arch/sh/Kconfig                              |  2 +-
>>   arch/sparc/Kconfig                           |  2 +-
>>   arch/x86/Kconfig                             |  2 +-
>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>   include/linux/gfp.h                          |  2 +-
>>   mm/hugetlb.c                                 | 57 ++++++++++++--------
>>   mm/page_alloc.c                              |  4 +-
>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>
>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>> index 091a513b93e9..af687eff884a 100644
>> --- a/arch/arm64/Kconfig
>> +++ b/arch/arm64/Kconfig
>> @@ -18,7 +18,7 @@ config ARM64
>>   	select ARCH_HAS_FAST_MULTIPLIER
>>   	select ARCH_HAS_FORTIFY_SOURCE
>>   	select ARCH_HAS_GCOV_PROFILE_ALL
>> -	select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>> +	select ARCH_HAS_GIGANTIC_PAGE
>>   	select ARCH_HAS_KCOV
>>   	select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>   	select ARCH_HAS_PTE_SPECIAL
>> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
>> index fb6609875455..59893e766824 100644
>> --- a/arch/arm64/include/asm/hugetlb.h
>> +++ b/arch/arm64/include/asm/hugetlb.h
>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
>>   
>>   #include <asm-generic/hugetlb.h>
>>   
>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> -static inline bool gigantic_page_supported(void) { return true; }
>> -#endif
>> -
>>   #endif /* __ASM_HUGETLB_H */
>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> index 5b0177733994..d04a0bcc2f1c 100644
>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate *hstate)
>>   	}
>>   }
>>   
>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> -static inline bool gigantic_page_supported(void)
>> -{
>> -	return true;
>> -}
>> -#endif
>> -
>>   /* hugepd entry valid bit */
>>   #define HUGEPD_VAL_BITS		(0x8000000000000000UL)
>>   
> As explained in https://patchwork.ozlabs.org/patch/1047003/
> architectures like ppc64 have a hypervisor assisted mechanism to indicate
> where to find gigantic huge pages(16G pages). At this point, we don't use this
> reserved pages for anything other than hugetlb backing and hence there
> is no runtime free of this pages needed ( Also we don't do
> runtime allocation of them).
>
> I guess you can still achieve what you want to do in this patch by
> keeping gigantic_page_supported()?
>
> NOTE: We should rename gigantic_page_supported to be more specific to
> support for runtime_alloc/free of gigantic pages
>
> -aneesh
>
Thanks for noticing Aneesh.

I can't find a better solution than bringing back 
gigantic_page_supported check,
since it is must be done at runtime in your case.
I'm not sure of one thing though: you say that freeing boottime gigantic 
pages
is not needed, but is it forbidden ? Just to know where the check and 
what its
new name should be.
Is something like that (on top of this series) ok for you (and everyone 
else) before
I send a v7:

diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
b/arch/powerpc/include/asm/book3s/64/hugetlb.h
index d04a0bc..d121559 100644
--- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
+++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
@@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate *hstate)
  /* hugepd entry valid bit */
  #define HUGEPD_VAL_BITS                (0x8000000000000000UL)

+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
+static inline bool gigantic_page_supported(void)
+{
+       /*
+        * We used gigantic page reservation with hypervisor assist in 
some case.
+        * We cannot use runtime allocation of gigantic pages in those 
platforms
+        * This is hash translation mode LPARs.
+        */
+       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+               return false;
+
+       return true;
+}
+#endif
+
  #endif
diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
index 71d7b77..7d12e73 100644
--- a/include/asm-generic/hugetlb.h
+++ b/include/asm-generic/hugetlb.h
@@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
  }
  #endif

+#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+static inline bool gigantic_page_supported(void)
+{
+        return true;
+}
+#else
+static inline bool gigantic_page_supported(void)
+{
+        return false;
+}
+#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
+#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
+
  #endif /* _ASM_GENERIC_HUGETLB_H */
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 9fc96ef..cfbbafe 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2425,6 +2425,11 @@ static ssize_t __nr_hugepages_store_common(bool 
obey_mempolicy,
         int err;
         NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
__GFP_NORETRY);

+       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
+               err = -EINVAL;
+               goto out;
+       }
+
         if (nid == NUMA_NO_NODE) {
                 /*
                  * global hstate attribute
@@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
obey_mempolicy,

         err = set_max_huge_pages(h, count, nodes_allowed);

+out:
         if (nodes_allowed != &node_states[N_MEMORY])
                 NODEMASK_FREE(nodes_allowed);










_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>
>>> On systems without CONTIG_ALLOC activated but that support gigantic 
>>> pages,
>>> boottime reserved gigantic pages can not be freed at all. This patch
>>> simply enables the possibility to hand back those pages to memory
>>> allocator.
>>>
>>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>>> ---
>>>   arch/arm64/Kconfig                           |  2 +-
>>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>>   arch/s390/Kconfig                            |  2 +-
>>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>>   arch/sh/Kconfig                              |  2 +-
>>>   arch/sparc/Kconfig                           |  2 +-
>>>   arch/x86/Kconfig                             |  2 +-
>>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>>   include/linux/gfp.h                          |  2 +-
>>>   mm/hugetlb.c                                 | 57 ++++++++++++--------
>>>   mm/page_alloc.c                              |  4 +-
>>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>>
>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>>> index 091a513b93e9..af687eff884a 100644
>>> --- a/arch/arm64/Kconfig
>>> +++ b/arch/arm64/Kconfig
>>> @@ -18,7 +18,7 @@ config ARM64
>>>       select ARCH_HAS_FAST_MULTIPLIER
>>>       select ARCH_HAS_FORTIFY_SOURCE
>>>       select ARCH_HAS_GCOV_PROFILE_ALL
>>> -    select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>>> +    select ARCH_HAS_GIGANTIC_PAGE
>>>       select ARCH_HAS_KCOV
>>>       select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>>       select ARCH_HAS_PTE_SPECIAL
>>> diff --git a/arch/arm64/include/asm/hugetlb.h 
>>> b/arch/arm64/include/asm/hugetlb.h
>>> index fb6609875455..59893e766824 100644
>>> --- a/arch/arm64/include/asm/hugetlb.h
>>> +++ b/arch/arm64/include/asm/hugetlb.h
>>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct 
>>> *mm, unsigned long addr,
>>>   #include <asm-generic/hugetlb.h>
>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>> -static inline bool gigantic_page_supported(void) { return true; }
>>> -#endif
>>> -
>>>   #endif /* __ASM_HUGETLB_H */
>>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> index 5b0177733994..d04a0bcc2f1c 100644
>>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate 
>>> *hstate)
>>>       }
>>>   }
>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>> -static inline bool gigantic_page_supported(void)
>>> -{
>>> -    return true;
>>> -}
>>> -#endif
>>> -
>>>   /* hugepd entry valid bit */
>>>   #define HUGEPD_VAL_BITS        (0x8000000000000000UL)
>> As explained in https://patchwork.ozlabs.org/patch/1047003/
>> architectures like ppc64 have a hypervisor assisted mechanism to indicate
>> where to find gigantic huge pages(16G pages). At this point, we don't 
>> use this
>> reserved pages for anything other than hugetlb backing and hence there
>> is no runtime free of this pages needed ( Also we don't do
>> runtime allocation of them).
>>
>> I guess you can still achieve what you want to do in this patch by
>> keeping gigantic_page_supported()?
>>
>> NOTE: We should rename gigantic_page_supported to be more specific to
>> support for runtime_alloc/free of gigantic pages
>>
>> -aneesh
>>
> Thanks for noticing Aneesh.
> 
> I can't find a better solution than bringing back 
> gigantic_page_supported check,
> since it is must be done at runtime in your case.
> I'm not sure of one thing though: you say that freeing boottime gigantic 
> pages
> is not needed, but is it forbidden ? Just to know where the check and 
> what its
> new name should be.
> Is something like that (on top of this series) ok for you (and everyone 
> else) before
> I send a v7:
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index d04a0bc..d121559 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate 
> *hstate)
>   /* hugepd entry valid bit */
>   #define HUGEPD_VAL_BITS                (0x8000000000000000UL)
> 
> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> +#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
> +static inline bool gigantic_page_supported(void)
> +{
> +       /*
> +        * We used gigantic page reservation with hypervisor assist in 
> some case.
> +        * We cannot use runtime allocation of gigantic pages in those 
> platforms
> +        * This is hash translation mode LPARs.
> +        */
> +       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
> +               return false;
> +
> +       return true;
> +}
> +#endif
> +
>   #endif
> diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
> index 71d7b77..7d12e73 100644
> --- a/include/asm-generic/hugetlb.h
> +++ b/include/asm-generic/hugetlb.h
> @@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
>   }
>   #endif
> 
> +#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE


The pattern i like is

#ifndef gigantic_page_supported
#define gigantic_page_supported gigantic_page_supported

static inline bool gigantic_page_supported(void)
{
         return true;
}

#endif

instead of _HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED.


> +static inline bool gigantic_page_supported(void)
> +{
> +        return true;
> +}
> +#else
> +static inline bool gigantic_page_supported(void)
> +{
> +        return false;
> +}
> +#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
> +#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
> +
>   #endif /* _ASM_GENERIC_HUGETLB_H */
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 9fc96ef..cfbbafe 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -2425,6 +2425,11 @@ static ssize_t __nr_hugepages_store_common(bool 
> obey_mempolicy,
>          int err;
>          NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
> __GFP_NORETRY);
> 
> +       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
> +               err = -EINVAL;
> +               goto out;
> +       }


you should restore other users of gigantic_page_supported() not just 
this. That will just make your earlier patch as removing 
gigantic_page_supported from every architecture other than ppc64 and 
have a generic version as above.


> +
>          if (nid == NUMA_NO_NODE) {
>                  /*
>                   * global hstate attribute
> @@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
> obey_mempolicy,
> 
>          err = set_max_huge_pages(h, count, nodes_allowed);
> 
> +out:
>          if (nodes_allowed != &node_states[N_MEMORY])
>                  NODEMASK_FREE(nodes_allowed);
> 
> 
> 
> 

-aneesh.

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>
>>> On systems without CONTIG_ALLOC activated but that support gigantic 
>>> pages,
>>> boottime reserved gigantic pages can not be freed at all. This patch
>>> simply enables the possibility to hand back those pages to memory
>>> allocator.
>>>
>>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>>> ---
>>>   arch/arm64/Kconfig                           |  2 +-
>>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>>   arch/s390/Kconfig                            |  2 +-
>>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>>   arch/sh/Kconfig                              |  2 +-
>>>   arch/sparc/Kconfig                           |  2 +-
>>>   arch/x86/Kconfig                             |  2 +-
>>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>>   include/linux/gfp.h                          |  2 +-
>>>   mm/hugetlb.c                                 | 57 ++++++++++++--------
>>>   mm/page_alloc.c                              |  4 +-
>>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>>
>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>>> index 091a513b93e9..af687eff884a 100644
>>> --- a/arch/arm64/Kconfig
>>> +++ b/arch/arm64/Kconfig
>>> @@ -18,7 +18,7 @@ config ARM64
>>>       select ARCH_HAS_FAST_MULTIPLIER
>>>       select ARCH_HAS_FORTIFY_SOURCE
>>>       select ARCH_HAS_GCOV_PROFILE_ALL
>>> -    select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>>> +    select ARCH_HAS_GIGANTIC_PAGE
>>>       select ARCH_HAS_KCOV
>>>       select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>>       select ARCH_HAS_PTE_SPECIAL
>>> diff --git a/arch/arm64/include/asm/hugetlb.h 
>>> b/arch/arm64/include/asm/hugetlb.h
>>> index fb6609875455..59893e766824 100644
>>> --- a/arch/arm64/include/asm/hugetlb.h
>>> +++ b/arch/arm64/include/asm/hugetlb.h
>>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct 
>>> *mm, unsigned long addr,
>>>   #include <asm-generic/hugetlb.h>
>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>> -static inline bool gigantic_page_supported(void) { return true; }
>>> -#endif
>>> -
>>>   #endif /* __ASM_HUGETLB_H */
>>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> index 5b0177733994..d04a0bcc2f1c 100644
>>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate 
>>> *hstate)
>>>       }
>>>   }
>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>> -static inline bool gigantic_page_supported(void)
>>> -{
>>> -    return true;
>>> -}
>>> -#endif
>>> -
>>>   /* hugepd entry valid bit */
>>>   #define HUGEPD_VAL_BITS        (0x8000000000000000UL)
>> As explained in https://patchwork.ozlabs.org/patch/1047003/
>> architectures like ppc64 have a hypervisor assisted mechanism to indicate
>> where to find gigantic huge pages(16G pages). At this point, we don't 
>> use this
>> reserved pages for anything other than hugetlb backing and hence there
>> is no runtime free of this pages needed ( Also we don't do
>> runtime allocation of them).
>>
>> I guess you can still achieve what you want to do in this patch by
>> keeping gigantic_page_supported()?
>>
>> NOTE: We should rename gigantic_page_supported to be more specific to
>> support for runtime_alloc/free of gigantic pages
>>
>> -aneesh
>>
> Thanks for noticing Aneesh.
> 
> I can't find a better solution than bringing back 
> gigantic_page_supported check,
> since it is must be done at runtime in your case.
> I'm not sure of one thing though: you say that freeing boottime gigantic 
> pages
> is not needed, but is it forbidden ? Just to know where the check and 
> what its
> new name should be.
> Is something like that (on top of this series) ok for you (and everyone 
> else) before
> I send a v7:
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index d04a0bc..d121559 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate 
> *hstate)
>   /* hugepd entry valid bit */
>   #define HUGEPD_VAL_BITS                (0x8000000000000000UL)
> 
> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> +#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
> +static inline bool gigantic_page_supported(void)
> +{
> +       /*
> +        * We used gigantic page reservation with hypervisor assist in 
> some case.
> +        * We cannot use runtime allocation of gigantic pages in those 
> platforms
> +        * This is hash translation mode LPARs.
> +        */
> +       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
> +               return false;
> +
> +       return true;
> +}
> +#endif
> +
>   #endif
> diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
> index 71d7b77..7d12e73 100644
> --- a/include/asm-generic/hugetlb.h
> +++ b/include/asm-generic/hugetlb.h
> @@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
>   }
>   #endif
> 
> +#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE


The pattern i like is

#ifndef gigantic_page_supported
#define gigantic_page_supported gigantic_page_supported

static inline bool gigantic_page_supported(void)
{
         return true;
}

#endif

instead of _HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED.


> +static inline bool gigantic_page_supported(void)
> +{
> +        return true;
> +}
> +#else
> +static inline bool gigantic_page_supported(void)
> +{
> +        return false;
> +}
> +#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
> +#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
> +
>   #endif /* _ASM_GENERIC_HUGETLB_H */
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 9fc96ef..cfbbafe 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -2425,6 +2425,11 @@ static ssize_t __nr_hugepages_store_common(bool 
> obey_mempolicy,
>          int err;
>          NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
> __GFP_NORETRY);
> 
> +       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
> +               err = -EINVAL;
> +               goto out;
> +       }


you should restore other users of gigantic_page_supported() not just 
this. That will just make your earlier patch as removing 
gigantic_page_supported from every architecture other than ppc64 and 
have a generic version as above.


> +
>          if (nid == NUMA_NO_NODE) {
>                  /*
>                   * global hstate attribute
> @@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
> obey_mempolicy,
> 
>          err = set_max_huge_pages(h, count, nodes_allowed);
> 
> +out:
>          if (nodes_allowed != &node_states[N_MEMORY])
>                  NODEMASK_FREE(nodes_allowed);
> 
> 
> 
> 

-aneesh.


_______________________________________________
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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>
>>> On systems without CONTIG_ALLOC activated but that support gigantic 
>>> pages,
>>> boottime reserved gigantic pages can not be freed at all. This patch
>>> simply enables the possibility to hand back those pages to memory
>>> allocator.
>>>
>>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>>> ---
>>>   arch/arm64/Kconfig                           |  2 +-
>>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>>   arch/s390/Kconfig                            |  2 +-
>>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>>   arch/sh/Kconfig                              |  2 +-
>>>   arch/sparc/Kconfig                           |  2 +-
>>>   arch/x86/Kconfig                             |  2 +-
>>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>>   include/linux/gfp.h                          |  2 +-
>>>   mm/hugetlb.c                                 | 57 ++++++++++++--------
>>>   mm/page_alloc.c                              |  4 +-
>>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>>
>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>>> index 091a513b93e9..af687eff884a 100644
>>> --- a/arch/arm64/Kconfig
>>> +++ b/arch/arm64/Kconfig
>>> @@ -18,7 +18,7 @@ config ARM64
>>>       select ARCH_HAS_FAST_MULTIPLIER
>>>       select ARCH_HAS_FORTIFY_SOURCE
>>>       select ARCH_HAS_GCOV_PROFILE_ALL
>>> -    select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>>> +    select ARCH_HAS_GIGANTIC_PAGE
>>>       select ARCH_HAS_KCOV
>>>       select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>>       select ARCH_HAS_PTE_SPECIAL
>>> diff --git a/arch/arm64/include/asm/hugetlb.h 
>>> b/arch/arm64/include/asm/hugetlb.h
>>> index fb6609875455..59893e766824 100644
>>> --- a/arch/arm64/include/asm/hugetlb.h
>>> +++ b/arch/arm64/include/asm/hugetlb.h
>>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct 
>>> *mm, unsigned long addr,
>>>   #include <asm-generic/hugetlb.h>
>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>> -static inline bool gigantic_page_supported(void) { return true; }
>>> -#endif
>>> -
>>>   #endif /* __ASM_HUGETLB_H */
>>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> index 5b0177733994..d04a0bcc2f1c 100644
>>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate 
>>> *hstate)
>>>       }
>>>   }
>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>> -static inline bool gigantic_page_supported(void)
>>> -{
>>> -    return true;
>>> -}
>>> -#endif
>>> -
>>>   /* hugepd entry valid bit */
>>>   #define HUGEPD_VAL_BITS        (0x8000000000000000UL)
>> As explained in https://patchwork.ozlabs.org/patch/1047003/
>> architectures like ppc64 have a hypervisor assisted mechanism to indicate
>> where to find gigantic huge pages(16G pages). At this point, we don't 
>> use this
>> reserved pages for anything other than hugetlb backing and hence there
>> is no runtime free of this pages needed ( Also we don't do
>> runtime allocation of them).
>>
>> I guess you can still achieve what you want to do in this patch by
>> keeping gigantic_page_supported()?
>>
>> NOTE: We should rename gigantic_page_supported to be more specific to
>> support for runtime_alloc/free of gigantic pages
>>
>> -aneesh
>>
> Thanks for noticing Aneesh.
> 
> I can't find a better solution than bringing back 
> gigantic_page_supported check,
> since it is must be done at runtime in your case.
> I'm not sure of one thing though: you say that freeing boottime gigantic 
> pages
> is not needed, but is it forbidden ? Just to know where the check and 
> what its
> new name should be.
> Is something like that (on top of this series) ok for you (and everyone 
> else) before
> I send a v7:
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> index d04a0bc..d121559 100644
> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
> @@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate 
> *hstate)
>   /* hugepd entry valid bit */
>   #define HUGEPD_VAL_BITS                (0x8000000000000000UL)
> 
> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
> +#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
> +static inline bool gigantic_page_supported(void)
> +{
> +       /*
> +        * We used gigantic page reservation with hypervisor assist in 
> some case.
> +        * We cannot use runtime allocation of gigantic pages in those 
> platforms
> +        * This is hash translation mode LPARs.
> +        */
> +       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
> +               return false;
> +
> +       return true;
> +}
> +#endif
> +
>   #endif
> diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
> index 71d7b77..7d12e73 100644
> --- a/include/asm-generic/hugetlb.h
> +++ b/include/asm-generic/hugetlb.h
> @@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
>   }
>   #endif
> 
> +#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE


The pattern i like is

#ifndef gigantic_page_supported
#define gigantic_page_supported gigantic_page_supported

static inline bool gigantic_page_supported(void)
{
         return true;
}

#endif

instead of _HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED.


> +static inline bool gigantic_page_supported(void)
> +{
> +        return true;
> +}
> +#else
> +static inline bool gigantic_page_supported(void)
> +{
> +        return false;
> +}
> +#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
> +#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
> +
>   #endif /* _ASM_GENERIC_HUGETLB_H */
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 9fc96ef..cfbbafe 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -2425,6 +2425,11 @@ static ssize_t __nr_hugepages_store_common(bool 
> obey_mempolicy,
>          int err;
>          NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
> __GFP_NORETRY);
> 
> +       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
> +               err = -EINVAL;
> +               goto out;
> +       }


you should restore other users of gigantic_page_supported() not just 
this. That will just make your earlier patch as removing 
gigantic_page_supported from every architecture other than ppc64 and 
have a generic version as above.


> +
>          if (nid = NUMA_NO_NODE) {
>                  /*
>                   * global hstate attribute
> @@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
> obey_mempolicy,
> 
>          err = set_max_huge_pages(h, count, nodes_allowed);
> 
> +out:
>          if (nodes_allowed != &node_states[N_MEMORY])
>                  NODEMASK_FREE(nodes_allowed);
> 
> 
> 
> 

-aneesh.

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On 03/14/2019 02:17 PM, Aneesh Kumar K.V wrote:
> On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
>> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>>
>>>> On systems without CONTIG_ALLOC activated but that support gigantic 
>>>> pages,
>>>> boottime reserved gigantic pages can not be freed at all. This patch
>>>> simply enables the possibility to hand back those pages to memory
>>>> allocator.
>>>>
>>>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>>>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>>>> ---
>>>>   arch/arm64/Kconfig                           |  2 +-
>>>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>>>   arch/s390/Kconfig                            |  2 +-
>>>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>>>   arch/sh/Kconfig                              |  2 +-
>>>>   arch/sparc/Kconfig                           |  2 +-
>>>>   arch/x86/Kconfig                             |  2 +-
>>>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>>>   include/linux/gfp.h                          |  2 +-
>>>>   mm/hugetlb.c                                 | 57 
>>>> ++++++++++++--------
>>>>   mm/page_alloc.c                              |  4 +-
>>>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>>>
>>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>>>> index 091a513b93e9..af687eff884a 100644
>>>> --- a/arch/arm64/Kconfig
>>>> +++ b/arch/arm64/Kconfig
>>>> @@ -18,7 +18,7 @@ config ARM64
>>>>       select ARCH_HAS_FAST_MULTIPLIER
>>>>       select ARCH_HAS_FORTIFY_SOURCE
>>>>       select ARCH_HAS_GCOV_PROFILE_ALL
>>>> -    select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>>>> +    select ARCH_HAS_GIGANTIC_PAGE
>>>>       select ARCH_HAS_KCOV
>>>>       select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>>>       select ARCH_HAS_PTE_SPECIAL
>>>> diff --git a/arch/arm64/include/asm/hugetlb.h 
>>>> b/arch/arm64/include/asm/hugetlb.h
>>>> index fb6609875455..59893e766824 100644
>>>> --- a/arch/arm64/include/asm/hugetlb.h
>>>> +++ b/arch/arm64/include/asm/hugetlb.h
>>>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct 
>>>> *mm, unsigned long addr,
>>>>   #include <asm-generic/hugetlb.h>
>>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>>> -static inline bool gigantic_page_supported(void) { return true; }
>>>> -#endif
>>>> -
>>>>   #endif /* __ASM_HUGETLB_H */
>>>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>>>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> index 5b0177733994..d04a0bcc2f1c 100644
>>>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate 
>>>> *hstate)
>>>>       }
>>>>   }
>>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>>> -static inline bool gigantic_page_supported(void)
>>>> -{
>>>> -    return true;
>>>> -}
>>>> -#endif
>>>> -
>>>>   /* hugepd entry valid bit */
>>>>   #define HUGEPD_VAL_BITS        (0x8000000000000000UL)
>>> As explained in https://patchwork.ozlabs.org/patch/1047003/
>>> architectures like ppc64 have a hypervisor assisted mechanism to 
>>> indicate
>>> where to find gigantic huge pages(16G pages). At this point, we 
>>> don't use this
>>> reserved pages for anything other than hugetlb backing and hence there
>>> is no runtime free of this pages needed ( Also we don't do
>>> runtime allocation of them).
>>>
>>> I guess you can still achieve what you want to do in this patch by
>>> keeping gigantic_page_supported()?
>>>
>>> NOTE: We should rename gigantic_page_supported to be more specific to
>>> support for runtime_alloc/free of gigantic pages
>>>
>>> -aneesh
>>>
>> Thanks for noticing Aneesh.
>>
>> I can't find a better solution than bringing back 
>> gigantic_page_supported check,
>> since it is must be done at runtime in your case.
>> I'm not sure of one thing though: you say that freeing boottime 
>> gigantic pages
>> is not needed, but is it forbidden ? Just to know where the check and 
>> what its
>> new name should be.

You did not answer this question: is freeing boottime gigantic pages 
"forbidden" or just
not needed ?


>> Is something like that (on top of this series) ok for you (and 
>> everyone else) before
>> I send a v7:
>>
>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> index d04a0bc..d121559 100644
>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> @@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate 
>> *hstate)
>>   /* hugepd entry valid bit */
>>   #define HUGEPD_VAL_BITS                (0x8000000000000000UL)
>>
>> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> +#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +       /*
>> +        * We used gigantic page reservation with hypervisor assist 
>> in some case.
>> +        * We cannot use runtime allocation of gigantic pages in 
>> those platforms
>> +        * This is hash translation mode LPARs.
>> +        */
>> +       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
>> +               return false;
>> +
>> +       return true;
>> +}
>> +#endif
>> +
>>   #endif
>> diff --git a/include/asm-generic/hugetlb.h 
>> b/include/asm-generic/hugetlb.h
>> index 71d7b77..7d12e73 100644
>> --- a/include/asm-generic/hugetlb.h
>> +++ b/include/asm-generic/hugetlb.h
>> @@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
>>   }
>>   #endif
>>
>> +#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
>> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>
>
> The pattern i like is
>
> #ifndef gigantic_page_supported
> #define gigantic_page_supported gigantic_page_supported
>
> static inline bool gigantic_page_supported(void)
> {
>         return true;
> }
>
> #endif
>
> instead of _HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED.
>

I see, that avoids a new define. However, it is not consistent with the 
rest of function definitions
in generic hugetlb.h. What do you think ? Should I follow the same 
format ? Or use yours ?

>
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +        return true;
>> +}
>> +#else
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +        return false;
>> +}
>> +#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
>> +#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
>> +
>>   #endif /* _ASM_GENERIC_HUGETLB_H */
>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
>> index 9fc96ef..cfbbafe 100644
>> --- a/mm/hugetlb.c
>> +++ b/mm/hugetlb.c
>> @@ -2425,6 +2425,11 @@ static ssize_t 
>> __nr_hugepages_store_common(bool obey_mempolicy,
>>          int err;
>>          NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
>> __GFP_NORETRY);
>>
>> +       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
>> +               err = -EINVAL;
>> +               goto out;
>> +       }
>
>
> you should restore other users of gigantic_page_supported() not just 
> this. That will just make your earlier patch as removing 
> gigantic_page_supported from every architecture other than ppc64 and 
> have a generic version as above.
>
>

I'll restore the check in update_and_free_page too depending on your 
answer to the above question,
since adding this check back would not allow to free boottime gigantic 
pages.

>> +
>>          if (nid = NUMA_NO_NODE) {
>>                  /*
>>                   * global hstate attribute
>> @@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
>> obey_mempolicy,
>>
>>          err = set_max_huge_pages(h, count, nodes_allowed);
>>
>> +out:
>>          if (nodes_allowed != &node_states[N_MEMORY])
>>                  NODEMASK_FREE(nodes_allowed);
>>
>>
>>
>>
>
> -aneesh.
>

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On 03/14/2019 02:17 PM, Aneesh Kumar K.V wrote:
> On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
>> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>>
>>>> On systems without CONTIG_ALLOC activated but that support gigantic 
>>>> pages,
>>>> boottime reserved gigantic pages can not be freed at all. This patch
>>>> simply enables the possibility to hand back those pages to memory
>>>> allocator.
>>>>
>>>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>>>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>>>> ---
>>>>   arch/arm64/Kconfig                           |  2 +-
>>>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>>>   arch/s390/Kconfig                            |  2 +-
>>>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>>>   arch/sh/Kconfig                              |  2 +-
>>>>   arch/sparc/Kconfig                           |  2 +-
>>>>   arch/x86/Kconfig                             |  2 +-
>>>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>>>   include/linux/gfp.h                          |  2 +-
>>>>   mm/hugetlb.c                                 | 57 
>>>> ++++++++++++--------
>>>>   mm/page_alloc.c                              |  4 +-
>>>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>>>
>>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>>>> index 091a513b93e9..af687eff884a 100644
>>>> --- a/arch/arm64/Kconfig
>>>> +++ b/arch/arm64/Kconfig
>>>> @@ -18,7 +18,7 @@ config ARM64
>>>>       select ARCH_HAS_FAST_MULTIPLIER
>>>>       select ARCH_HAS_FORTIFY_SOURCE
>>>>       select ARCH_HAS_GCOV_PROFILE_ALL
>>>> -    select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>>>> +    select ARCH_HAS_GIGANTIC_PAGE
>>>>       select ARCH_HAS_KCOV
>>>>       select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>>>       select ARCH_HAS_PTE_SPECIAL
>>>> diff --git a/arch/arm64/include/asm/hugetlb.h 
>>>> b/arch/arm64/include/asm/hugetlb.h
>>>> index fb6609875455..59893e766824 100644
>>>> --- a/arch/arm64/include/asm/hugetlb.h
>>>> +++ b/arch/arm64/include/asm/hugetlb.h
>>>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct 
>>>> *mm, unsigned long addr,
>>>>   #include <asm-generic/hugetlb.h>
>>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>>> -static inline bool gigantic_page_supported(void) { return true; }
>>>> -#endif
>>>> -
>>>>   #endif /* __ASM_HUGETLB_H */
>>>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>>>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> index 5b0177733994..d04a0bcc2f1c 100644
>>>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate 
>>>> *hstate)
>>>>       }
>>>>   }
>>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>>> -static inline bool gigantic_page_supported(void)
>>>> -{
>>>> -    return true;
>>>> -}
>>>> -#endif
>>>> -
>>>>   /* hugepd entry valid bit */
>>>>   #define HUGEPD_VAL_BITS        (0x8000000000000000UL)
>>> As explained in https://patchwork.ozlabs.org/patch/1047003/
>>> architectures like ppc64 have a hypervisor assisted mechanism to 
>>> indicate
>>> where to find gigantic huge pages(16G pages). At this point, we 
>>> don't use this
>>> reserved pages for anything other than hugetlb backing and hence there
>>> is no runtime free of this pages needed ( Also we don't do
>>> runtime allocation of them).
>>>
>>> I guess you can still achieve what you want to do in this patch by
>>> keeping gigantic_page_supported()?
>>>
>>> NOTE: We should rename gigantic_page_supported to be more specific to
>>> support for runtime_alloc/free of gigantic pages
>>>
>>> -aneesh
>>>
>> Thanks for noticing Aneesh.
>>
>> I can't find a better solution than bringing back 
>> gigantic_page_supported check,
>> since it is must be done at runtime in your case.
>> I'm not sure of one thing though: you say that freeing boottime 
>> gigantic pages
>> is not needed, but is it forbidden ? Just to know where the check and 
>> what its
>> new name should be.

You did not answer this question: is freeing boottime gigantic pages 
"forbidden" or just
not needed ?


>> Is something like that (on top of this series) ok for you (and 
>> everyone else) before
>> I send a v7:
>>
>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> index d04a0bc..d121559 100644
>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> @@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate 
>> *hstate)
>>   /* hugepd entry valid bit */
>>   #define HUGEPD_VAL_BITS                (0x8000000000000000UL)
>>
>> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> +#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +       /*
>> +        * We used gigantic page reservation with hypervisor assist 
>> in some case.
>> +        * We cannot use runtime allocation of gigantic pages in 
>> those platforms
>> +        * This is hash translation mode LPARs.
>> +        */
>> +       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
>> +               return false;
>> +
>> +       return true;
>> +}
>> +#endif
>> +
>>   #endif
>> diff --git a/include/asm-generic/hugetlb.h 
>> b/include/asm-generic/hugetlb.h
>> index 71d7b77..7d12e73 100644
>> --- a/include/asm-generic/hugetlb.h
>> +++ b/include/asm-generic/hugetlb.h
>> @@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
>>   }
>>   #endif
>>
>> +#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
>> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>
>
> The pattern i like is
>
> #ifndef gigantic_page_supported
> #define gigantic_page_supported gigantic_page_supported
>
> static inline bool gigantic_page_supported(void)
> {
>         return true;
> }
>
> #endif
>
> instead of _HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED.
>

I see, that avoids a new define. However, it is not consistent with the 
rest of function definitions
in generic hugetlb.h. What do you think ? Should I follow the same 
format ? Or use yours ?

>
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +        return true;
>> +}
>> +#else
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +        return false;
>> +}
>> +#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
>> +#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
>> +
>>   #endif /* _ASM_GENERIC_HUGETLB_H */
>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
>> index 9fc96ef..cfbbafe 100644
>> --- a/mm/hugetlb.c
>> +++ b/mm/hugetlb.c
>> @@ -2425,6 +2425,11 @@ static ssize_t 
>> __nr_hugepages_store_common(bool obey_mempolicy,
>>          int err;
>>          NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
>> __GFP_NORETRY);
>>
>> +       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
>> +               err = -EINVAL;
>> +               goto out;
>> +       }
>
>
> you should restore other users of gigantic_page_supported() not just 
> this. That will just make your earlier patch as removing 
> gigantic_page_supported from every architecture other than ppc64 and 
> have a generic version as above.
>
>

I'll restore the check in update_and_free_page too depending on your 
answer to the above question,
since adding this check back would not allow to free boottime gigantic 
pages.

>> +
>>          if (nid == NUMA_NO_NODE) {
>>                  /*
>>                   * global hstate attribute
>> @@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
>> obey_mempolicy,
>>
>>          err = set_max_huge_pages(h, count, nodes_allowed);
>>
>> +out:
>>          if (nodes_allowed != &node_states[N_MEMORY])
>>                  NODEMASK_FREE(nodes_allowed);
>>
>>
>>
>>
>
> -aneesh.
>

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Alexandre Ghiti]

On 03/14/2019 02:17 PM, Aneesh Kumar K.V wrote:
> On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
>> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>>
>>>> On systems without CONTIG_ALLOC activated but that support gigantic 
>>>> pages,
>>>> boottime reserved gigantic pages can not be freed at all. This patch
>>>> simply enables the possibility to hand back those pages to memory
>>>> allocator.
>>>>
>>>> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
>>>> Acked-by: David S. Miller <davem@davemloft.net> [sparc]
>>>> ---
>>>>   arch/arm64/Kconfig                           |  2 +-
>>>>   arch/arm64/include/asm/hugetlb.h             |  4 --
>>>>   arch/powerpc/include/asm/book3s/64/hugetlb.h |  7 ---
>>>>   arch/powerpc/platforms/Kconfig.cputype       |  2 +-
>>>>   arch/s390/Kconfig                            |  2 +-
>>>>   arch/s390/include/asm/hugetlb.h              |  3 --
>>>>   arch/sh/Kconfig                              |  2 +-
>>>>   arch/sparc/Kconfig                           |  2 +-
>>>>   arch/x86/Kconfig                             |  2 +-
>>>>   arch/x86/include/asm/hugetlb.h               |  4 --
>>>>   include/linux/gfp.h                          |  2 +-
>>>>   mm/hugetlb.c                                 | 57 
>>>> ++++++++++++--------
>>>>   mm/page_alloc.c                              |  4 +-
>>>>   13 files changed, 44 insertions(+), 49 deletions(-)
>>>>
>>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>>>> index 091a513b93e9..af687eff884a 100644
>>>> --- a/arch/arm64/Kconfig
>>>> +++ b/arch/arm64/Kconfig
>>>> @@ -18,7 +18,7 @@ config ARM64
>>>>       select ARCH_HAS_FAST_MULTIPLIER
>>>>       select ARCH_HAS_FORTIFY_SOURCE
>>>>       select ARCH_HAS_GCOV_PROFILE_ALL
>>>> -    select ARCH_HAS_GIGANTIC_PAGE if CONTIG_ALLOC
>>>> +    select ARCH_HAS_GIGANTIC_PAGE
>>>>       select ARCH_HAS_KCOV
>>>>       select ARCH_HAS_MEMBARRIER_SYNC_CORE
>>>>       select ARCH_HAS_PTE_SPECIAL
>>>> diff --git a/arch/arm64/include/asm/hugetlb.h 
>>>> b/arch/arm64/include/asm/hugetlb.h
>>>> index fb6609875455..59893e766824 100644
>>>> --- a/arch/arm64/include/asm/hugetlb.h
>>>> +++ b/arch/arm64/include/asm/hugetlb.h
>>>> @@ -65,8 +65,4 @@ extern void set_huge_swap_pte_at(struct mm_struct 
>>>> *mm, unsigned long addr,
>>>>   #include <asm-generic/hugetlb.h>
>>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>>> -static inline bool gigantic_page_supported(void) { return true; }
>>>> -#endif
>>>> -
>>>>   #endif /* __ASM_HUGETLB_H */
>>>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>>>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> index 5b0177733994..d04a0bcc2f1c 100644
>>>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>>>> @@ -32,13 +32,6 @@ static inline int hstate_get_psize(struct hstate 
>>>> *hstate)
>>>>       }
>>>>   }
>>>> -#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>>>> -static inline bool gigantic_page_supported(void)
>>>> -{
>>>> -    return true;
>>>> -}
>>>> -#endif
>>>> -
>>>>   /* hugepd entry valid bit */
>>>>   #define HUGEPD_VAL_BITS        (0x8000000000000000UL)
>>> As explained in https://patchwork.ozlabs.org/patch/1047003/
>>> architectures like ppc64 have a hypervisor assisted mechanism to 
>>> indicate
>>> where to find gigantic huge pages(16G pages). At this point, we 
>>> don't use this
>>> reserved pages for anything other than hugetlb backing and hence there
>>> is no runtime free of this pages needed ( Also we don't do
>>> runtime allocation of them).
>>>
>>> I guess you can still achieve what you want to do in this patch by
>>> keeping gigantic_page_supported()?
>>>
>>> NOTE: We should rename gigantic_page_supported to be more specific to
>>> support for runtime_alloc/free of gigantic pages
>>>
>>> -aneesh
>>>
>> Thanks for noticing Aneesh.
>>
>> I can't find a better solution than bringing back 
>> gigantic_page_supported check,
>> since it is must be done at runtime in your case.
>> I'm not sure of one thing though: you say that freeing boottime 
>> gigantic pages
>> is not needed, but is it forbidden ? Just to know where the check and 
>> what its
>> new name should be.

You did not answer this question: is freeing boottime gigantic pages 
"forbidden" or just
not needed ?


>> Is something like that (on top of this series) ok for you (and 
>> everyone else) before
>> I send a v7:
>>
>> diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h 
>> b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> index d04a0bc..d121559 100644
>> --- a/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> +++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
>> @@ -35,4 +35,20 @@ static inline int hstate_get_psize(struct hstate 
>> *hstate)
>>   /* hugepd entry valid bit */
>>   #define HUGEPD_VAL_BITS                (0x8000000000000000UL)
>>
>> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>> +#define __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +       /*
>> +        * We used gigantic page reservation with hypervisor assist 
>> in some case.
>> +        * We cannot use runtime allocation of gigantic pages in 
>> those platforms
>> +        * This is hash translation mode LPARs.
>> +        */
>> +       if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
>> +               return false;
>> +
>> +       return true;
>> +}
>> +#endif
>> +
>>   #endif
>> diff --git a/include/asm-generic/hugetlb.h 
>> b/include/asm-generic/hugetlb.h
>> index 71d7b77..7d12e73 100644
>> --- a/include/asm-generic/hugetlb.h
>> +++ b/include/asm-generic/hugetlb.h
>> @@ -126,4 +126,18 @@ static inline pte_t huge_ptep_get(pte_t *ptep)
>>   }
>>   #endif
>>
>> +#ifndef __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED
>> +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
>
>
> The pattern i like is
>
> #ifndef gigantic_page_supported
> #define gigantic_page_supported gigantic_page_supported
>
> static inline bool gigantic_page_supported(void)
> {
>         return true;
> }
>
> #endif
>
> instead of _HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED.
>

I see, that avoids a new define. However, it is not consistent with the 
rest of function definitions
in generic hugetlb.h. What do you think ? Should I follow the same 
format ? Or use yours ?

>
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +        return true;
>> +}
>> +#else
>> +static inline bool gigantic_page_supported(void)
>> +{
>> +        return false;
>> +}
>> +#endif /* CONFIG_ARCH_HAS_GIGANTIC_PAGE */
>> +#endif /* __HAVE_ARCH_GIGANTIC_PAGE_SUPPORTED */
>> +
>>   #endif /* _ASM_GENERIC_HUGETLB_H */
>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
>> index 9fc96ef..cfbbafe 100644
>> --- a/mm/hugetlb.c
>> +++ b/mm/hugetlb.c
>> @@ -2425,6 +2425,11 @@ static ssize_t 
>> __nr_hugepages_store_common(bool obey_mempolicy,
>>          int err;
>>          NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | 
>> __GFP_NORETRY);
>>
>> +       if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
>> +               err = -EINVAL;
>> +               goto out;
>> +       }
>
>
> you should restore other users of gigantic_page_supported() not just 
> this. That will just make your earlier patch as removing 
> gigantic_page_supported from every architecture other than ppc64 and 
> have a generic version as above.
>
>

I'll restore the check in update_and_free_page too depending on your 
answer to the above question,
since adding this check back would not allow to free boottime gigantic 
pages.

>> +
>>          if (nid == NUMA_NO_NODE) {
>>                  /*
>>                   * global hstate attribute
>> @@ -2446,6 +2451,7 @@ static ssize_t __nr_hugepages_store_common(bool 
>> obey_mempolicy,
>>
>>          err = set_max_huge_pages(h, count, nodes_allowed);
>>
>> +out:
>>          if (nodes_allowed != &node_states[N_MEMORY])
>>                  NODEMASK_FREE(nodes_allowed);
>>
>>
>>
>>
>
> -aneesh.
>


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Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

On 3/14/19 7:22 PM, Alexandre Ghiti wrote:
> 
> 
> On 03/14/2019 02:17 PM, Aneesh Kumar K.V wrote:
>> On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
>>> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>>>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>>>
>>
>>> Thanks for noticing Aneesh.
>>>
>>> I can't find a better solution than bringing back 
>>> gigantic_page_supported check,
>>> since it is must be done at runtime in your case.
>>> I'm not sure of one thing though: you say that freeing boottime 
>>> gigantic pages
>>> is not needed, but is it forbidden ? Just to know where the check and 
>>> what its
>>> new name should be.
> 
> You did not answer this question: is freeing boottime gigantic pages 
> "forbidden" or just
> not needed ?

IMHO if we don't allow runtime allocation of gigantic hugepage, we 
should not allow runtime free of gigantic hugepage. Now w.r.t ppc64, 
hypervisor pass hints about the gignatic hugepages via device tree 
nodes. Early in boot we mark these pages as reserved and during hugetlb 
init we use these reserved pages for backing hugetlb fs.

Now "forbidden" is not the exact reason. We don't have code to put it 
back in the reserved list. Hence I would say "not supported".

-aneesh

Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

On 3/14/19 7:22 PM, Alexandre Ghiti wrote:
> 
> 
> On 03/14/2019 02:17 PM, Aneesh Kumar K.V wrote:
>> On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
>>> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>>>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>>>
>>
>>> Thanks for noticing Aneesh.
>>>
>>> I can't find a better solution than bringing back 
>>> gigantic_page_supported check,
>>> since it is must be done at runtime in your case.
>>> I'm not sure of one thing though: you say that freeing boottime 
>>> gigantic pages
>>> is not needed, but is it forbidden ? Just to know where the check and 
>>> what its
>>> new name should be.
> 
> You did not answer this question: is freeing boottime gigantic pages 
> "forbidden" or just
> not needed ?

IMHO if we don't allow runtime allocation of gigantic hugepage, we 
should not allow runtime free of gigantic hugepage. Now w.r.t ppc64, 
hypervisor pass hints about the gignatic hugepages via device tree 
nodes. Early in boot we mark these pages as reserved and during hugetlb 
init we use these reserved pages for backing hugetlb fs.

Now "forbidden" is not the exact reason. We don't have code to put it 
back in the reserved list. Hence I would say "not supported".

-aneesh


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Re: [PATCH v6 4/4] hugetlb: allow to free gigantic pages regardless of the configuration

[Aneesh Kumar K.V]

On 3/14/19 7:22 PM, Alexandre Ghiti wrote:
> 
> 
> On 03/14/2019 02:17 PM, Aneesh Kumar K.V wrote:
>> On 3/14/19 5:13 PM, Alexandre Ghiti wrote:
>>> On 03/14/2019 06:52 AM, Aneesh Kumar K.V wrote:
>>>> Alexandre Ghiti <alex@ghiti.fr> writes:
>>>>
>>
>>> Thanks for noticing Aneesh.
>>>
>>> I can't find a better solution than bringing back 
>>> gigantic_page_supported check,
>>> since it is must be done at runtime in your case.
>>> I'm not sure of one thing though: you say that freeing boottime 
>>> gigantic pages
>>> is not needed, but is it forbidden ? Just to know where the check and 
>>> what its
>>> new name should be.
> 
> You did not answer this question: is freeing boottime gigantic pages 
> "forbidden" or just
> not needed ?

IMHO if we don't allow runtime allocation of gigantic hugepage, we 
should not allow runtime free of gigantic hugepage. Now w.r.t ppc64, 
hypervisor pass hints about the gignatic hugepages via device tree 
nodes. Early in boot we mark these pages as reserved and during hugetlb 
init we use these reserved pages for backing hugetlb fs.

Now "forbidden" is not the exact reason. We don't have code to put it 
back in the reserved list. Hence I would say "not supported".

-aneesh