diff options
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 34 |
1 files changed, 22 insertions, 12 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index e5c00f2b98ab..ec4555369e17 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -906,7 +906,8 @@ static void page_check_dirty_writeback(struct page *page, * Anonymous pages are not handled by flushers and must be written * from reclaim context. Do not stall reclaim based on them */ - if (!page_is_file_cache(page)) { + if (!page_is_file_cache(page) || + (PageAnon(page) && !PageSwapBacked(page))) { *dirty = false; *writeback = false; return; @@ -987,7 +988,8 @@ static unsigned long shrink_page_list(struct list_head *page_list, goto keep_locked; /* Double the slab pressure for mapped and swapcache pages */ - if (page_mapped(page) || PageSwapCache(page)) + if ((page_mapped(page) || PageSwapCache(page)) && + !(PageAnon(page) && !PageSwapBacked(page))) sc->nr_scanned++; may_enter_fs = (sc->gfp_mask & __GFP_FS) || @@ -1113,8 +1115,10 @@ static unsigned long shrink_page_list(struct list_head *page_list, /* * Anonymous process memory has backing store? * Try to allocate it some swap space here. + * Lazyfree page could be freed directly */ - if (PageAnon(page) && !PageSwapCache(page)) { + if (PageAnon(page) && PageSwapBacked(page) && + !PageSwapCache(page)) { if (!(sc->gfp_mask & __GFP_IO)) goto keep_locked; if (!add_to_swap(page, page_list)) @@ -1135,9 +1139,12 @@ static unsigned long shrink_page_list(struct list_head *page_list, * The page is mapped into the page tables of one or more * processes. Try to unmap it here. */ - if (page_mapped(page) && mapping) { + if (page_mapped(page)) { switch (ret = try_to_unmap(page, ttu_flags | TTU_BATCH_FLUSH)) { + case SWAP_DIRTY: + SetPageSwapBacked(page); + /* fall through */ case SWAP_FAIL: nr_unmap_fail++; goto activate_locked; @@ -1145,8 +1152,6 @@ static unsigned long shrink_page_list(struct list_head *page_list, goto keep_locked; case SWAP_MLOCK: goto cull_mlocked; - case SWAP_LZFREE: - goto lazyfree; case SWAP_SUCCESS: ; /* try to free the page below */ } @@ -1258,10 +1263,18 @@ static unsigned long shrink_page_list(struct list_head *page_list, } } -lazyfree: - if (!mapping || !__remove_mapping(mapping, page, true)) - goto keep_locked; + if (PageAnon(page) && !PageSwapBacked(page)) { + /* follow __remove_mapping for reference */ + if (!page_ref_freeze(page, 1)) + goto keep_locked; + if (PageDirty(page)) { + page_ref_unfreeze(page, 1); + goto keep_locked; + } + count_vm_event(PGLAZYFREED); + } else if (!mapping || !__remove_mapping(mapping, page, true)) + goto keep_locked; /* * At this point, we have no other references and there is * no way to pick any more up (removed from LRU, removed @@ -1271,9 +1284,6 @@ lazyfree: */ __ClearPageLocked(page); free_it: - if (ret == SWAP_LZFREE) - count_vm_event(PGLAZYFREED); - nr_reclaimed++; /* |