From: Naoya Horiguchi Date: Fri, 8 Sep 2017 23:11:04 +0000 (-0700) Subject: mm: soft-dirty: keep soft-dirty bits over thp migration X-Git-Tag: v4.14-rc1~83^2~119 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=ab6e3d0939bb332d72444a532f0f72e0dfde7b7b;p=linux.git mm: soft-dirty: keep soft-dirty bits over thp migration Soft dirty bit is designed to keep tracked over page migration. This patch makes it work in the same manner for thp migration too. Signed-off-by: Naoya Horiguchi Signed-off-by: Zi Yan Cc: "H. Peter Anvin" Cc: Anshuman Khandual Cc: Dave Hansen Cc: David Nellans Cc: Ingo Molnar Cc: Kirill A. Shutemov Cc: Mel Gorman Cc: Minchan Kim Cc: Thomas Gleixner Cc: Vlastimil Babka Cc: Andrea Arcangeli Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index bbeae4a2bd01..5b4c44d419c5 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -1172,6 +1172,23 @@ static inline pte_t pte_swp_clear_soft_dirty(pte_t pte) { return pte_clear_flags(pte, _PAGE_SWP_SOFT_DIRTY); } + +#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION +static inline pmd_t pmd_swp_mksoft_dirty(pmd_t pmd) +{ + return pmd_set_flags(pmd, _PAGE_SWP_SOFT_DIRTY); +} + +static inline int pmd_swp_soft_dirty(pmd_t pmd) +{ + return pmd_flags(pmd) & _PAGE_SWP_SOFT_DIRTY; +} + +static inline pmd_t pmd_swp_clear_soft_dirty(pmd_t pmd) +{ + return pmd_clear_flags(pmd, _PAGE_SWP_SOFT_DIRTY); +} +#endif #endif #define PKRU_AD_BIT 0x1 diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 8eec35af32e4..4b21c4e51ce4 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -978,17 +978,22 @@ static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, { pmd_t pmd = *pmdp; - /* See comment in change_huge_pmd() */ - pmdp_invalidate(vma, addr, pmdp); - if (pmd_dirty(*pmdp)) - pmd = pmd_mkdirty(pmd); - if (pmd_young(*pmdp)) - pmd = pmd_mkyoung(pmd); - - pmd = pmd_wrprotect(pmd); - pmd = pmd_clear_soft_dirty(pmd); - - set_pmd_at(vma->vm_mm, addr, pmdp, pmd); + if (pmd_present(pmd)) { + /* See comment in change_huge_pmd() */ + pmdp_invalidate(vma, addr, pmdp); + if (pmd_dirty(*pmdp)) + pmd = pmd_mkdirty(pmd); + if (pmd_young(*pmdp)) + pmd = pmd_mkyoung(pmd); + + pmd = pmd_wrprotect(pmd); + pmd = pmd_clear_soft_dirty(pmd); + + set_pmd_at(vma->vm_mm, addr, pmdp, pmd); + } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { + pmd = pmd_swp_clear_soft_dirty(pmd); + set_pmd_at(vma->vm_mm, addr, pmdp, pmd); + } } #else static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 4f93a6d10a47..8e0243036564 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -630,7 +630,24 @@ static inline void ptep_modify_prot_commit(struct mm_struct *mm, #define arch_start_context_switch(prev) do {} while (0) #endif -#ifndef CONFIG_HAVE_ARCH_SOFT_DIRTY +#ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY +#ifndef CONFIG_ARCH_ENABLE_THP_MIGRATION +static inline pmd_t pmd_swp_mksoft_dirty(pmd_t pmd) +{ + return pmd; +} + +static inline int pmd_swp_soft_dirty(pmd_t pmd) +{ + return 0; +} + +static inline pmd_t pmd_swp_clear_soft_dirty(pmd_t pmd) +{ + return pmd; +} +#endif +#else /* !CONFIG_HAVE_ARCH_SOFT_DIRTY */ static inline int pte_soft_dirty(pte_t pte) { return 0; @@ -675,6 +692,21 @@ static inline pte_t pte_swp_clear_soft_dirty(pte_t pte) { return pte; } + +static inline pmd_t pmd_swp_mksoft_dirty(pmd_t pmd) +{ + return pmd; +} + +static inline int pmd_swp_soft_dirty(pmd_t pmd) +{ + return 0; +} + +static inline pmd_t pmd_swp_clear_soft_dirty(pmd_t pmd) +{ + return pmd; +} #endif #ifndef __HAVE_PFNMAP_TRACKING diff --git a/include/linux/swapops.h b/include/linux/swapops.h index 82089fd88c29..45b092aa6419 100644 --- a/include/linux/swapops.h +++ b/include/linux/swapops.h @@ -183,6 +183,8 @@ static inline swp_entry_t pmd_to_swp_entry(pmd_t pmd) { swp_entry_t arch_entry; + if (pmd_swp_soft_dirty(pmd)) + pmd = pmd_swp_clear_soft_dirty(pmd); arch_entry = __pmd_to_swp_entry(pmd); return swp_entry(__swp_type(arch_entry), __swp_offset(arch_entry)); } diff --git a/mm/huge_memory.c b/mm/huge_memory.c index b82585eabe85..269b5df58543 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -937,6 +937,8 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm, if (is_write_migration_entry(entry)) { make_migration_entry_read(&entry); pmd = swp_entry_to_pmd(entry); + if (pmd_swp_soft_dirty(*src_pmd)) + pmd = pmd_swp_mksoft_dirty(pmd); set_pmd_at(src_mm, addr, src_pmd, pmd); } set_pmd_at(dst_mm, addr, dst_pmd, pmd); @@ -1756,6 +1758,17 @@ static inline int pmd_move_must_withdraw(spinlock_t *new_pmd_ptl, } #endif +static pmd_t move_soft_dirty_pmd(pmd_t pmd) +{ +#ifdef CONFIG_MEM_SOFT_DIRTY + if (unlikely(is_pmd_migration_entry(pmd))) + pmd = pmd_swp_mksoft_dirty(pmd); + else if (pmd_present(pmd)) + pmd = pmd_mksoft_dirty(pmd); +#endif + return pmd; +} + bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr, unsigned long new_addr, unsigned long old_end, pmd_t *old_pmd, pmd_t *new_pmd, bool *need_flush) @@ -1798,7 +1811,8 @@ bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr, pgtable = pgtable_trans_huge_withdraw(mm, old_pmd); pgtable_trans_huge_deposit(mm, new_pmd, pgtable); } - set_pmd_at(mm, new_addr, new_pmd, pmd_mksoft_dirty(pmd)); + pmd = move_soft_dirty_pmd(pmd); + set_pmd_at(mm, new_addr, new_pmd, pmd); if (new_ptl != old_ptl) spin_unlock(new_ptl); if (force_flush) @@ -1846,6 +1860,8 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, */ make_migration_entry_read(&entry); newpmd = swp_entry_to_pmd(entry); + if (pmd_swp_soft_dirty(*pmd)) + newpmd = pmd_swp_mksoft_dirty(newpmd); set_pmd_at(mm, addr, pmd, newpmd); } goto unlock; @@ -2824,6 +2840,7 @@ void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw, unsigned long address = pvmw->address; pmd_t pmdval; swp_entry_t entry; + pmd_t pmdswp; if (!(pvmw->pmd && !pvmw->pte)) return; @@ -2837,8 +2854,10 @@ void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw, if (pmd_dirty(pmdval)) set_page_dirty(page); entry = make_migration_entry(page, pmd_write(pmdval)); - pmdval = swp_entry_to_pmd(entry); - set_pmd_at(mm, address, pvmw->pmd, pmdval); + pmdswp = swp_entry_to_pmd(entry); + if (pmd_soft_dirty(pmdval)) + pmdswp = pmd_swp_mksoft_dirty(pmdswp); + set_pmd_at(mm, address, pvmw->pmd, pmdswp); page_remove_rmap(page, true); put_page(page); @@ -2861,6 +2880,8 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new) entry = pmd_to_swp_entry(*pvmw->pmd); get_page(new); pmde = pmd_mkold(mk_huge_pmd(new, vma->vm_page_prot)); + if (pmd_swp_soft_dirty(*pvmw->pmd)) + pmde = pmd_mksoft_dirty(pmde); if (is_write_migration_entry(entry)) pmde = maybe_pmd_mkwrite(pmde, vma);