From 4b10e7d562c90d0a72f324832c26653947a07381 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Thu, 25 Oct 2012 14:16:32 +0200 Subject: mm: mempolicy: Implement change_prot_numa() in terms of change_protection() This patch converts change_prot_numa() to use change_protection(). As pte_numa and friends check the PTE bits directly it is necessary for change_protection() to use pmd_mknuma(). Hence the required modifications to change_protection() are a little clumsy but the end result is that most of the numa page table helpers are just one or two instructions. Signed-off-by: Mel Gorman --- mm/mprotect.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 56 insertions(+), 16 deletions(-) (limited to 'mm/mprotect.c') diff --git a/mm/mprotect.c b/mm/mprotect.c index 7c3628a8b486..7ef6ae964e8f 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -35,10 +35,11 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) } #endif -static unsigned long change_pte_range(struct mm_struct *mm, pmd_t *pmd, +static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t newprot, - int dirty_accountable) + int dirty_accountable, int prot_numa) { + struct mm_struct *mm = vma->vm_mm; pte_t *pte, oldpte; spinlock_t *ptl; unsigned long pages = 0; @@ -49,19 +50,39 @@ static unsigned long change_pte_range(struct mm_struct *mm, pmd_t *pmd, oldpte = *pte; if (pte_present(oldpte)) { pte_t ptent; + bool updated = false; ptent = ptep_modify_prot_start(mm, addr, pte); - ptent = pte_modify(ptent, newprot); + if (!prot_numa) { + ptent = pte_modify(ptent, newprot); + updated = true; + } else { + struct page *page; + + page = vm_normal_page(vma, addr, oldpte); + if (page) { + /* only check non-shared pages */ + if (!pte_numa(oldpte) && + page_mapcount(page) == 1) { + ptent = pte_mknuma(ptent); + updated = true; + } + } + } /* * Avoid taking write faults for pages we know to be * dirty. */ - if (dirty_accountable && pte_dirty(ptent)) + if (dirty_accountable && pte_dirty(ptent)) { ptent = pte_mkwrite(ptent); + updated = true; + } + + if (updated) + pages++; ptep_modify_prot_commit(mm, addr, pte, ptent); - pages++; } else if (IS_ENABLED(CONFIG_MIGRATION) && !pte_file(oldpte)) { swp_entry_t entry = pte_to_swp_entry(oldpte); @@ -83,9 +104,25 @@ static unsigned long change_pte_range(struct mm_struct *mm, pmd_t *pmd, return pages; } +#ifdef CONFIG_NUMA_BALANCING +static inline void change_pmd_protnuma(struct mm_struct *mm, unsigned long addr, + pmd_t *pmd) +{ + spin_lock(&mm->page_table_lock); + set_pmd_at(mm, addr & PMD_MASK, pmd, pmd_mknuma(*pmd)); + spin_unlock(&mm->page_table_lock); +} +#else +static inline void change_pmd_protnuma(struct mm_struct *mm, unsigned long addr, + pmd_t *pmd) +{ + BUG(); +} +#endif /* CONFIG_NUMA_BALANCING */ + static inline unsigned long change_pmd_range(struct vm_area_struct *vma, pud_t *pud, unsigned long addr, unsigned long end, pgprot_t newprot, - int dirty_accountable) + int dirty_accountable, int prot_numa) { pmd_t *pmd; unsigned long next; @@ -97,7 +134,7 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma, pud_t * if (pmd_trans_huge(*pmd)) { if (next - addr != HPAGE_PMD_SIZE) split_huge_page_pmd(vma->vm_mm, pmd); - else if (change_huge_pmd(vma, pmd, addr, newprot)) { + else if (change_huge_pmd(vma, pmd, addr, newprot, prot_numa)) { pages += HPAGE_PMD_NR; continue; } @@ -105,8 +142,11 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma, pud_t * } if (pmd_none_or_clear_bad(pmd)) continue; - pages += change_pte_range(vma->vm_mm, pmd, addr, next, newprot, - dirty_accountable); + pages += change_pte_range(vma, pmd, addr, next, newprot, + dirty_accountable, prot_numa); + + if (prot_numa) + change_pmd_protnuma(vma->vm_mm, addr, pmd); } while (pmd++, addr = next, addr != end); return pages; @@ -114,7 +154,7 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma, pud_t * static inline unsigned long change_pud_range(struct vm_area_struct *vma, pgd_t *pgd, unsigned long addr, unsigned long end, pgprot_t newprot, - int dirty_accountable) + int dirty_accountable, int prot_numa) { pud_t *pud; unsigned long next; @@ -126,7 +166,7 @@ static inline unsigned long change_pud_range(struct vm_area_struct *vma, pgd_t * if (pud_none_or_clear_bad(pud)) continue; pages += change_pmd_range(vma, pud, addr, next, newprot, - dirty_accountable); + dirty_accountable, prot_numa); } while (pud++, addr = next, addr != end); return pages; @@ -134,7 +174,7 @@ static inline unsigned long change_pud_range(struct vm_area_struct *vma, pgd_t * static unsigned long change_protection_range(struct vm_area_struct *vma, unsigned long addr, unsigned long end, pgprot_t newprot, - int dirty_accountable) + int dirty_accountable, int prot_numa) { struct mm_struct *mm = vma->vm_mm; pgd_t *pgd; @@ -150,7 +190,7 @@ static unsigned long change_protection_range(struct vm_area_struct *vma, if (pgd_none_or_clear_bad(pgd)) continue; pages += change_pud_range(vma, pgd, addr, next, newprot, - dirty_accountable); + dirty_accountable, prot_numa); } while (pgd++, addr = next, addr != end); /* Only flush the TLB if we actually modified any entries: */ @@ -162,7 +202,7 @@ static unsigned long change_protection_range(struct vm_area_struct *vma, unsigned long change_protection(struct vm_area_struct *vma, unsigned long start, unsigned long end, pgprot_t newprot, - int dirty_accountable) + int dirty_accountable, int prot_numa) { struct mm_struct *mm = vma->vm_mm; unsigned long pages; @@ -171,7 +211,7 @@ unsigned long change_protection(struct vm_area_struct *vma, unsigned long start, if (is_vm_hugetlb_page(vma)) pages = hugetlb_change_protection(vma, start, end, newprot); else - pages = change_protection_range(vma, start, end, newprot, dirty_accountable); + pages = change_protection_range(vma, start, end, newprot, dirty_accountable, prot_numa); mmu_notifier_invalidate_range_end(mm, start, end); return pages; @@ -249,7 +289,7 @@ success: dirty_accountable = 1; } - change_protection(vma, start, end, vma->vm_page_prot, dirty_accountable); + change_protection(vma, start, end, vma->vm_page_prot, dirty_accountable, 0); vm_stat_account(mm, oldflags, vma->vm_file, -nrpages); vm_stat_account(mm, newflags, vma->vm_file, nrpages); -- cgit v1.2.3