diff options
author | Kirill A. Shutemov <kirill@shutemov.name> | 2014-12-10 15:44:36 -0800 |
---|---|---|
committer | Sasha Levin <sasha.levin@oracle.com> | 2016-06-03 11:30:36 -0400 |
commit | 20b97db882d78bedb7c66c40008bbd3a0d7edabd (patch) | |
tree | cc2fd1b0da6f84c2fd68ef17be2e1003a1f1afde /arch | |
parent | aee24401991708c95e7b3189119fc917f1fc16b8 (diff) |
mm: fix huge zero page accounting in smaps report
[ Upstream commit c164e038eee805147e95789dddb88ae3b3aca11c ]
As a small zero page, huge zero page should not be accounted in smaps
report as normal page.
For small pages we rely on vm_normal_page() to filter out zero page, but
vm_normal_page() is not designed to handle pmds. We only get here due
hackish cast pmd to pte in smaps_pte_range() -- pte and pmd format is not
necessary compatible on each and every architecture.
Let's add separate codepath to handle pmds. follow_trans_huge_pmd() will
detect huge zero page for us.
We would need pmd_dirty() helper to do this properly. The patch adds it
to THP-enabled architectures which don't yet have one.
[akpm@linux-foundation.org: use do_div to fix 32-bit build]
Signed-off-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Tested-by: Fengwei Yin <yfw.kernel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arm64/include/asm/pgtable.h | 1 | ||||
-rw-r--r-- | arch/powerpc/include/asm/pgtable-ppc64.h | 1 | ||||
-rw-r--r-- | arch/sparc/include/asm/pgtable_64.h | 7 | ||||
-rw-r--r-- | arch/x86/include/asm/pgtable.h | 5 |
4 files changed, 14 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index fba3e59e0c78..d583a58877fd 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -281,6 +281,7 @@ void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, #endif /* CONFIG_HAVE_RCU_TABLE_FREE */ #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +#define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd)) #define pmd_young(pmd) pte_young(pmd_pte(pmd)) #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd))) #define pmd_mksplitting(pmd) pte_pmd(pte_mkspecial(pmd_pte(pmd))) diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h index daf4add50743..59830c87d6b6 100644 --- a/arch/powerpc/include/asm/pgtable-ppc64.h +++ b/arch/powerpc/include/asm/pgtable-ppc64.h @@ -479,6 +479,7 @@ static inline pte_t *pmdp_ptep(pmd_t *pmd) } #define pmd_pfn(pmd) pte_pfn(pmd_pte(pmd)) +#define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd)) #define pmd_young(pmd) pte_young(pmd_pte(pmd)) #define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd))) #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd))) diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h index bfeb626085ac..1ff9e7864168 100644 --- a/arch/sparc/include/asm/pgtable_64.h +++ b/arch/sparc/include/asm/pgtable_64.h @@ -667,6 +667,13 @@ static inline unsigned long pmd_pfn(pmd_t pmd) } #ifdef CONFIG_TRANSPARENT_HUGEPAGE +static inline unsigned long pmd_dirty(pmd_t pmd) +{ + pte_t pte = __pte(pmd_val(pmd)); + + return pte_dirty(pte); +} + static inline unsigned long pmd_young(pmd_t pmd) { pte_t pte = __pte(pmd_val(pmd)); diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index aa97a070f09f..081d6f45e006 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -99,6 +99,11 @@ static inline int pte_young(pte_t pte) return pte_flags(pte) & _PAGE_ACCESSED; } +static inline int pmd_dirty(pmd_t pmd) +{ + return pmd_flags(pmd) & _PAGE_DIRTY; +} + static inline int pmd_young(pmd_t pmd) { return pmd_flags(pmd) & _PAGE_ACCESSED; |