From: Minchan Kim <minchan@xxxxxxxxxx> Subject: mm: factor out common parts between MADV_COLD and MADV_PAGEOUT There are many common parts between MADV_COLD and MADV_PAGEOUT. This patch factor them out to save code duplication. Link: http://lkml.kernel.org/r/20190726023435.214162-6-minchan@xxxxxxxxxx Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> Suggested-by: Johannes Weiner <hannes@xxxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: Chris Zankel <chris@xxxxxxxxxx> Cc: Daniel Colascione <dancol@xxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Hillf Danton <hdanton@xxxxxxxx> Cc: James E.J. Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> Cc: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx> Cc: kbuild test robot <lkp@xxxxxxxxx> Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Oleksandr Natalenko <oleksandr@xxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: Richard Henderson <rth@xxxxxxxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Cc: Sonny Rao <sonnyrao@xxxxxxxxxx> Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx> Cc: Tim Murray <timmurray@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/madvise.c | 192 +++++++++++-------------------------------------- 1 file changed, 45 insertions(+), 147 deletions(-) --- a/mm/madvise.c~mm-factor-out-common-parts-between-madv_cold-and-madv_pageout +++ a/mm/madvise.c @@ -32,6 +32,11 @@ #include "internal.h" +struct madvise_walk_private { + struct mmu_gather *tlb; + bool pageout; +}; + /* * Any behaviour which results in changes to the vma->vm_flags needs to * take mmap_sem for writing. Others, which simply traverse vmas, need @@ -292,15 +297,22 @@ static long madvise_willneed(struct vm_a return 0; } -static int madvise_cold_pte_range(pmd_t *pmd, unsigned long addr, - unsigned long end, struct mm_walk *walk) +static int madvise_cold_or_pageout_pte_range(pmd_t *pmd, + unsigned long addr, unsigned long end, + struct mm_walk *walk) { - struct mmu_gather *tlb = walk->private; + struct madvise_walk_private *private = walk->private; + struct mmu_gather *tlb = private->tlb; + bool pageout = private->pageout; struct mm_struct *mm = tlb->mm; struct vm_area_struct *vma = walk->vma; pte_t *orig_pte, *pte, ptent; spinlock_t *ptl; - struct page *page; + struct page *page = NULL; + LIST_HEAD(page_list); + + if (fatal_signal_pending(current)) + return -EINTR; #ifdef CONFIG_TRANSPARENT_HUGEPAGE if (pmd_trans_huge(*pmd)) { @@ -348,10 +360,17 @@ static int madvise_cold_pte_range(pmd_t tlb_remove_pmd_tlb_entry(tlb, pmd, addr); } + ClearPageReferenced(page); test_and_clear_page_young(page); - deactivate_page(page); + if (pageout) { + if (!isolate_lru_page(page)) + list_add(&page->lru, &page_list); + } else + deactivate_page(page); huge_unlock: spin_unlock(ptl); + if (pageout) + reclaim_pages(&page_list); return 0; } @@ -419,27 +438,39 @@ regular_page: * As a side effect, it makes confuse idle-page tracking * because they will miss recent referenced history. */ + ClearPageReferenced(page); test_and_clear_page_young(page); - deactivate_page(page); + if (pageout) { + if (!isolate_lru_page(page)) + list_add(&page->lru, &page_list); + } else + deactivate_page(page); } arch_leave_lazy_mmu_mode(); pte_unmap_unlock(orig_pte, ptl); + if (pageout) + reclaim_pages(&page_list); cond_resched(); return 0; } static const struct mm_walk_ops cold_walk_ops = { - .pmd_entry = madvise_cold_pte_range, + .pmd_entry = madvise_cold_or_pageout_pte_range, }; static void madvise_cold_page_range(struct mmu_gather *tlb, struct vm_area_struct *vma, unsigned long addr, unsigned long end) { + struct madvise_walk_private walk_private = { + .pageout = false, + .tlb = tlb, + }; + tlb_start_vma(tlb, vma); - walk_page_range(vma->vm_mm, addr, end, &cold_walk_ops, NULL); + walk_page_range(vma->vm_mm, addr, end, &cold_walk_ops, &walk_private); tlb_end_vma(tlb, vma); } @@ -462,150 +493,17 @@ static long madvise_cold(struct vm_area_ return 0; } -static int madvise_pageout_pte_range(pmd_t *pmd, unsigned long addr, - unsigned long end, struct mm_walk *walk) -{ - struct mmu_gather *tlb = walk->private; - struct mm_struct *mm = tlb->mm; - struct vm_area_struct *vma = walk->vma; - pte_t *orig_pte, *pte, ptent; - spinlock_t *ptl; - LIST_HEAD(page_list); - struct page *page; - - if (fatal_signal_pending(current)) - return -EINTR; - -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - if (pmd_trans_huge(*pmd)) { - pmd_t orig_pmd; - unsigned long next = pmd_addr_end(addr, end); - - tlb_change_page_size(tlb, HPAGE_PMD_SIZE); - ptl = pmd_trans_huge_lock(pmd, vma); - if (!ptl) - return 0; - - orig_pmd = *pmd; - if (is_huge_zero_pmd(orig_pmd)) - goto huge_unlock; - - if (unlikely(!pmd_present(orig_pmd))) { - VM_BUG_ON(thp_migration_supported() && - !is_pmd_migration_entry(orig_pmd)); - goto huge_unlock; - } - - page = pmd_page(orig_pmd); - if (next - addr != HPAGE_PMD_SIZE) { - int err; - - if (page_mapcount(page) != 1) - goto huge_unlock; - get_page(page); - spin_unlock(ptl); - lock_page(page); - err = split_huge_page(page); - unlock_page(page); - put_page(page); - if (!err) - goto regular_page; - return 0; - } - - if (pmd_young(orig_pmd)) { - pmdp_invalidate(vma, addr, pmd); - orig_pmd = pmd_mkold(orig_pmd); - - set_pmd_at(mm, addr, pmd, orig_pmd); - tlb_remove_tlb_entry(tlb, pmd, addr); - } - - ClearPageReferenced(page); - test_and_clear_page_young(page); - - if (!isolate_lru_page(page)) - list_add(&page->lru, &page_list); -huge_unlock: - spin_unlock(ptl); - reclaim_pages(&page_list); - return 0; - } - - if (pmd_trans_unstable(pmd)) - return 0; -regular_page: -#endif - tlb_change_page_size(tlb, PAGE_SIZE); - orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); - flush_tlb_batched_pending(mm); - arch_enter_lazy_mmu_mode(); - for (; addr < end; pte++, addr += PAGE_SIZE) { - ptent = *pte; - if (!pte_present(ptent)) - continue; - - page = vm_normal_page(vma, addr, ptent); - if (!page) - continue; - - /* - * creating a THP page is expensive so split it only if we - * are sure it's worth. Split it if we are only owner. - */ - if (PageTransCompound(page)) { - if (page_mapcount(page) != 1) - break; - get_page(page); - if (!trylock_page(page)) { - put_page(page); - break; - } - pte_unmap_unlock(orig_pte, ptl); - if (split_huge_page(page)) { - unlock_page(page); - put_page(page); - pte_offset_map_lock(mm, pmd, addr, &ptl); - break; - } - unlock_page(page); - put_page(page); - pte = pte_offset_map_lock(mm, pmd, addr, &ptl); - pte--; - addr -= PAGE_SIZE; - continue; - } - - VM_BUG_ON_PAGE(PageTransCompound(page), page); - - if (pte_young(ptent)) { - ptent = ptep_get_and_clear_full(mm, addr, pte, - tlb->fullmm); - ptent = pte_mkold(ptent); - set_pte_at(mm, addr, pte, ptent); - tlb_remove_tlb_entry(tlb, pte, addr); - } - ClearPageReferenced(page); - test_and_clear_page_young(page); - - if (!isolate_lru_page(page)) - list_add(&page->lru, &page_list); - } - - arch_leave_lazy_mmu_mode(); - pte_unmap_unlock(orig_pte, ptl); - reclaim_pages(&page_list); - cond_resched(); - - return 0; -} - static void madvise_pageout_page_range(struct mmu_gather *tlb, struct vm_area_struct *vma, unsigned long addr, unsigned long end) { + struct madvise_walk_private walk_private = { + .pageout = true, + .tlb = tlb, + }; + tlb_start_vma(tlb, vma); - walk_page_range(vma->vm_mm, addr, end, &cold_walk_ops, NULL); + walk_page_range(vma->vm_mm, addr, end, &cold_walk_ops, &walk_private); tlb_end_vma(tlb, vma); } _
