diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index ee1c244a62a1..528454c2caa9 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -99,7 +99,11 @@ extern int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, extern int handle_pte_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, pte_t *pte, pmd_t *pmd, unsigned int flags); -extern int split_huge_page(struct page *page); +extern int split_huge_page_to_list(struct page *page, struct list_head *list); +static inline int split_huge_page(struct page *page) +{ + return split_huge_page_to_list(page, NULL); +} extern void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address, pmd_t *pmd); #define split_huge_page_pmd(__vma, __address, __pmd) \ @@ -186,6 +190,11 @@ extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vm #define transparent_hugepage_enabled(__vma) 0 #define transparent_hugepage_flags 0UL +static inline int +split_huge_page_to_list(struct page *page, struct list_head *list) +{ + return 0; +} static inline int split_huge_page(struct page *page) { return 0; diff --git a/include/linux/swap.h b/include/linux/swap.h index b5b12c71a2af..1701ce4be746 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -236,7 +236,7 @@ extern unsigned long nr_free_pagecache_pages(void); extern void __lru_cache_add(struct page *, enum lru_list lru); extern void lru_cache_add_lru(struct page *, enum lru_list lru); extern void lru_add_page_tail(struct page *page, struct page *page_tail, - struct lruvec *lruvec); + struct lruvec *lruvec, struct list_head *head); extern void activate_page(struct page *); extern void mark_page_accessed(struct page *); extern void lru_add_drain(void); @@ -346,7 +346,7 @@ extern struct address_space swapper_spaces[]; #define swap_address_space(entry) (&swapper_spaces[swp_type(entry)]) extern unsigned long total_swapcache_pages(void); extern void show_swap_cache_info(void); -extern int add_to_swap(struct page *); +extern int add_to_swap(struct page *, struct list_head *list); extern int add_to_swap_cache(struct page *, swp_entry_t, gfp_t); extern int __add_to_swap_cache(struct page *page, swp_entry_t entry); extern void __delete_from_swap_cache(struct page *); @@ -465,7 +465,7 @@ static inline struct page *lookup_swap_cache(swp_entry_t swp) return NULL; } -static inline int add_to_swap(struct page *page) +static inline int add_to_swap(struct page *page, struct list_head *list) { return 0; } diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 45eaae030628..2ed1a160a85b 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1559,7 +1559,8 @@ static int __split_huge_page_splitting(struct page *page, return ret; } -static void __split_huge_page_refcount(struct page *page) +static void __split_huge_page_refcount(struct page *page, + struct list_head *list) { int i; struct zone *zone = page_zone(page); @@ -1645,7 +1646,7 @@ static void __split_huge_page_refcount(struct page *page) BUG_ON(!PageDirty(page_tail)); BUG_ON(!PageSwapBacked(page_tail)); - lru_add_page_tail(page, page_tail, lruvec); + lru_add_page_tail(page, page_tail, lruvec, list); } atomic_sub(tail_count, &page->_count); BUG_ON(atomic_read(&page->_count) <= 0); @@ -1752,7 +1753,8 @@ static int __split_huge_page_map(struct page *page, /* must be called with anon_vma->root->rwsem held */ static void __split_huge_page(struct page *page, - struct anon_vma *anon_vma) + struct anon_vma *anon_vma, + struct list_head *list) { int mapcount, mapcount2; pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); @@ -1783,7 +1785,7 @@ static void __split_huge_page(struct page *page, mapcount, page_mapcount(page)); BUG_ON(mapcount != page_mapcount(page)); - __split_huge_page_refcount(page); + __split_huge_page_refcount(page, list); mapcount2 = 0; anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff, pgoff) { @@ -1798,7 +1800,14 @@ static void __split_huge_page(struct page *page, BUG_ON(mapcount != mapcount2); } -int split_huge_page(struct page *page) +/* + * Split a hugepage into normal pages. This doesn't change the position of head + * page. If @list is null, tail pages will be added to LRU list, otherwise, to + * @list. Both head page and tail pages will inherit mapping, flags, and so on + * from the hugepage. + * Return 0 if the hugepage is split successfully otherwise return 1. + */ +int split_huge_page_to_list(struct page *page, struct list_head *list) { struct anon_vma *anon_vma; int ret = 1; @@ -1823,7 +1832,7 @@ int split_huge_page(struct page *page) goto out_unlock; BUG_ON(!PageSwapBacked(page)); - __split_huge_page(page, anon_vma); + __split_huge_page(page, anon_vma, list); count_vm_event(THP_SPLIT); BUG_ON(PageCompound(page)); diff --git a/mm/swap.c b/mm/swap.c index 8a529a01e8fc..acd40bfffa82 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -737,7 +737,7 @@ EXPORT_SYMBOL(__pagevec_release); #ifdef CONFIG_TRANSPARENT_HUGEPAGE /* used by __split_huge_page_refcount() */ void lru_add_page_tail(struct page *page, struct page *page_tail, - struct lruvec *lruvec) + struct lruvec *lruvec, struct list_head *list) { int uninitialized_var(active); enum lru_list lru; @@ -749,7 +749,8 @@ void lru_add_page_tail(struct page *page, struct page *page_tail, VM_BUG_ON(NR_CPUS != 1 && !spin_is_locked(&lruvec_zone(lruvec)->lru_lock)); - SetPageLRU(page_tail); + if (!list) + SetPageLRU(page_tail); if (page_evictable(page_tail)) { if (PageActive(page)) { @@ -767,7 +768,11 @@ void lru_add_page_tail(struct page *page, struct page *page_tail, if (likely(PageLRU(page))) list_add_tail(&page_tail->lru, &page->lru); - else { + else if (list) { + /* page reclaim is reclaiming a huge page */ + get_page(page_tail); + list_add_tail(&page_tail->lru, list); + } else { struct list_head *list_head; /* * Head page has not yet been counted, as an hpage, diff --git a/mm/swap_state.c b/mm/swap_state.c index fe43fd5578cf..b3d40dcf3624 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -160,7 +160,7 @@ void __delete_from_swap_cache(struct page *page) * Allocate swap space for the page and add the page to the * swap cache. Caller needs to hold the page lock. */ -int add_to_swap(struct page *page) +int add_to_swap(struct page *page, struct list_head *list) { swp_entry_t entry; int err; @@ -173,7 +173,7 @@ int add_to_swap(struct page *page) return 0; if (unlikely(PageTransHuge(page))) - if (unlikely(split_huge_page(page))) { + if (unlikely(split_huge_page_to_list(page, list))) { swapcache_free(entry, NULL); return 0; } diff --git a/mm/vmscan.c b/mm/vmscan.c index e53e49584cf3..fa6a85378ee4 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -781,7 +781,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, if (PageAnon(page) && !PageSwapCache(page)) { if (!(sc->gfp_mask & __GFP_IO)) goto keep_locked; - if (!add_to_swap(page)) + if (!add_to_swap(page, page_list)) goto activate_locked; may_enter_fs = 1; }