diff options
| -rw-r--r-- | include/linux/rmap.h | 2 | ||||
| -rw-r--r-- | mm/rmap.c | 3 | ||||
| -rw-r--r-- | mm/vmscan.c | 45 |
3 files changed, 36 insertions, 14 deletions
diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 72be23b..d25bd22 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -209,7 +209,7 @@ static inline int page_referenced(struct page *page, int is_locked, unsigned long *vm_flags) { *vm_flags = 0; - return TestClearPageReferenced(page); + return 0; } #define try_to_unmap(page, refs) SWAP_FAIL @@ -601,9 +601,6 @@ int page_referenced(struct page *page, int referenced = 0; int we_locked = 0; - if (TestClearPageReferenced(page)) - referenced++; - *vm_flags = 0; if (page_mapped(page) && page_rmapping(page)) { if (!is_locked && (!PageAnon(page) || PageKsm(page))) { diff --git a/mm/vmscan.c b/mm/vmscan.c index d9a0e0d..79c8098 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -561,18 +561,18 @@ redo: enum page_references { PAGEREF_RECLAIM, PAGEREF_RECLAIM_CLEAN, + PAGEREF_KEEP, PAGEREF_ACTIVATE, }; static enum page_references page_check_references(struct page *page, struct scan_control *sc) { + int referenced_ptes, referenced_page; unsigned long vm_flags; - int referenced; - referenced = page_referenced(page, 1, sc->mem_cgroup, &vm_flags); - if (!referenced) - return PAGEREF_RECLAIM; + referenced_ptes = page_referenced(page, 1, sc->mem_cgroup, &vm_flags); + referenced_page = TestClearPageReferenced(page); /* Lumpy reclaim - ignore references */ if (sc->order > PAGE_ALLOC_COSTLY_ORDER) @@ -585,11 +585,36 @@ static enum page_references page_check_references(struct page *page, if (vm_flags & VM_LOCKED) return PAGEREF_RECLAIM; - if (page_mapped(page)) - return PAGEREF_ACTIVATE; + if (referenced_ptes) { + if (PageAnon(page)) + return PAGEREF_ACTIVATE; + /* + * All mapped pages start out with page table + * references from the instantiating fault, so we need + * to look twice if a mapped file page is used more + * than once. + * + * Mark it and spare it for another trip around the + * inactive list. Another page table reference will + * lead to its activation. + * + * Note: the mark is set for activated pages as well + * so that recently deactivated but used pages are + * quickly recovered. + */ + SetPageReferenced(page); + + if (referenced_page) + return PAGEREF_ACTIVATE; + + return PAGEREF_KEEP; + } /* Reclaim if clean, defer dirty pages to writeback */ - return PAGEREF_RECLAIM_CLEAN; + if (referenced_page) + return PAGEREF_RECLAIM_CLEAN; + + return PAGEREF_RECLAIM; } /* @@ -657,6 +682,8 @@ static unsigned long shrink_page_list(struct list_head *page_list, switch (references) { case PAGEREF_ACTIVATE: goto activate_locked; + case PAGEREF_KEEP: + goto keep_locked; case PAGEREF_RECLAIM: case PAGEREF_RECLAIM_CLEAN: ; /* try to reclaim the page below */ @@ -1359,9 +1386,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, continue; } - /* page_referenced clears PageReferenced */ - if (page_mapped(page) && - page_referenced(page, 0, sc->mem_cgroup, &vm_flags)) { + if (page_referenced(page, 0, sc->mem_cgroup, &vm_flags)) { nr_rotated++; /* * Identify referenced, file-backed active pages and |
