From: Jaewon Kim Date: Tue, 8 Sep 2015 22:02:21 +0000 (-0700) Subject: vmscan: fix increasing nr_isolated incurred by putback unevictable pages X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c54839a722a02818677bcabe57e957f0ce4f841d;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git vmscan: fix increasing nr_isolated incurred by putback unevictable pages reclaim_clean_pages_from_list() assumes that shrink_page_list() returns number of pages removed from the candidate list. But shrink_page_list() puts back mlocked pages without passing it to caller and without counting as nr_reclaimed. This increases nr_isolated. To fix this, this patch changes shrink_page_list() to pass unevictable pages back to caller. Caller will take care those pages. Minchan said: It fixes two issues. 1. With unevictable page, cma_alloc will be successful. Exactly speaking, cma_alloc of current kernel will fail due to unevictable pages. 2. fix leaking of NR_ISOLATED counter of vmstat With it, too_many_isolated works. Otherwise, it could make hang until the process get SIGKILL. Signed-off-by: Jaewon Kim Acked-by: Minchan Kim Cc: Mel Gorman Acked-by: Vlastimil Babka Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/vmscan.c b/mm/vmscan.c index 0b1aab411cb0..8276a3a615ca 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1196,7 +1196,7 @@ cull_mlocked: if (PageSwapCache(page)) try_to_free_swap(page); unlock_page(page); - putback_lru_page(page); + list_add(&page->lru, &ret_pages); continue; activate_locked: