From 3e79ec7ddc33e5c69c20ce7f768d0e5c8b824f69 Mon Sep 17 00:00:00 2001 From: Vladimir Davydov Date: Tue, 26 Jul 2016 15:24:30 -0700 Subject: [PATCH] arch: x86: charge page tables to kmemcg Page tables can bite a relatively big chunk off system memory and their allocations are easy to trigger from userspace, so they should be accounted to kmemcg. This patch marks page table allocations as __GFP_ACCOUNT for x86. Note we must not charge allocations of kernel page tables, because they can be shared among processes from different cgroups so accounting them to a particular one can pin other cgroups for indefinitely long. So we clear __GFP_ACCOUNT flag if a page table is allocated for the kernel. Link: http://lkml.kernel.org/r/7d5c54f6a2bcbe76f03171689440003d87e6c742.1464079538.git.vdavydov@virtuozzo.com Signed-off-by: Vladimir Davydov Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Johannes Weiner Cc: Michal Hocko Cc: Eric Dumazet Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/include/asm/pgalloc.h | 12 ++++++++++-- arch/x86/mm/pgtable.c | 10 +++++++--- 2 files changed, 17 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h index 574c23cf761a..b6d425999f99 100644 --- a/arch/x86/include/asm/pgalloc.h +++ b/arch/x86/include/asm/pgalloc.h @@ -81,7 +81,11 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr) { struct page *page; - page = alloc_pages(GFP_KERNEL | __GFP_ZERO, 0); + gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO; + + if (mm == &init_mm) + gfp &= ~__GFP_ACCOUNT; + page = alloc_pages(gfp, 0); if (!page) return NULL; if (!pgtable_pmd_page_ctor(page)) { @@ -125,7 +129,11 @@ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud) static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr) { - return (pud_t *)get_zeroed_page(GFP_KERNEL); + gfp_t gfp = GFP_KERNEL_ACCOUNT; + + if (mm == &init_mm) + gfp &= ~__GFP_ACCOUNT; + return (pud_t *)get_zeroed_page(gfp); } static inline void pud_free(struct mm_struct *mm, pud_t *pud) diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index aa0ff4b02a96..3feec5af4e67 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -6,7 +6,7 @@ #include #include -#define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO +#define PGALLOC_GFP (GFP_KERNEL_ACCOUNT | __GFP_NOTRACK | __GFP_ZERO) #ifdef CONFIG_HIGHPTE #define PGALLOC_USER_GFP __GFP_HIGHMEM @@ -18,7 +18,7 @@ gfp_t __userpte_alloc_gfp = PGALLOC_GFP | PGALLOC_USER_GFP; pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) { - return (pte_t *)__get_free_page(PGALLOC_GFP); + return (pte_t *)__get_free_page(PGALLOC_GFP & ~__GFP_ACCOUNT); } pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address) @@ -207,9 +207,13 @@ static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[]) { int i; bool failed = false; + gfp_t gfp = PGALLOC_GFP; + + if (mm == &init_mm) + gfp &= ~__GFP_ACCOUNT; for(i = 0; i < PREALLOCATED_PMDS; i++) { - pmd_t *pmd = (pmd_t *)__get_free_page(PGALLOC_GFP); + pmd_t *pmd = (pmd_t *)__get_free_page(gfp); if (!pmd) failed = true; if (pmd && !pgtable_pmd_page_ctor(virt_to_page(pmd))) { -- 2.30.2