From f7ad2a6cb9f7c4040004bedee84a70a9b985583e Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Wed, 3 May 2017 14:52:29 -0700 Subject: mm: move MADV_FREE pages into LRU_INACTIVE_FILE list madv()'s MADV_FREE indicate pages are 'lazyfree'. They are still anonymous pages, but they can be freed without pageout. To distinguish these from normal anonymous pages, we clear their SwapBacked flag. MADV_FREE pages could be freed without pageout, so they pretty much like used once file pages. For such pages, we'd like to reclaim them once there is memory pressure. Also it might be unfair reclaiming MADV_FREE pages always before used once file pages and we definitively want to reclaim the pages before other anonymous and file pages. To speed up MADV_FREE pages reclaim, we put the pages into LRU_INACTIVE_FILE list. The rationale is LRU_INACTIVE_FILE list is tiny nowadays and should be full of used once file pages. Reclaiming MADV_FREE pages will not have much interfere of anonymous and active file pages. And the inactive file pages and MADV_FREE pages will be reclaimed according to their age, so we don't reclaim too many MADV_FREE pages too. Putting the MADV_FREE pages into LRU_INACTIVE_FILE_LIST also means we can reclaim the pages without swap support. This idea is suggested by Johannes. This patch doesn't move MADV_FREE pages to LRU_INACTIVE_FILE list yet to avoid bisect failure, next patch will do it. The patch is based on Minchan's original patch. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/2f87063c1e9354677b7618c647abde77b07561e5.1487965799.git.shli@fb.com Signed-off-by: Shaohua Li Suggested-by: Johannes Weiner Acked-by: Johannes Weiner Acked-by: Minchan Kim Acked-by: Michal Hocko Acked-by: Hillf Danton Cc: Hugh Dickins Cc: Rik van Riel Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/madvise.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'mm/madvise.c') diff --git a/mm/madvise.c b/mm/madvise.c index 7a2abf0127ae..cf3021b05b32 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -411,8 +411,6 @@ static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, ptent = pte_mkold(ptent); ptent = pte_mkclean(ptent); set_pte_at(mm, addr, pte, ptent); - if (PageActive(page)) - deactivate_page(page); tlb_remove_tlb_entry(tlb, pte, addr); } } -- cgit v1.2.3