]> Gitweb @ Texas Instruments - Open Source Git Repositories - git.TI.com/gitweb - android-sdk/kernel-video.git/commit
vmscan: fix increasing nr_isolated incurred by putback unevictable pages
authorJaewon Kim <jaewon31.kim@samsung.com>
Tue, 8 Sep 2015 22:02:21 +0000 (15:02 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 1 Oct 2015 09:36:14 +0000 (11:36 +0200)
commit8803492d518ccbdafeabda75d5eabe433319214d
treefeca32ce169fc2a528b81f21a86c859552898411
parent136af9b85ad0406325ab846e5148e3dfabea43c7
vmscan: fix increasing nr_isolated incurred by putback unevictable pages

commit c54839a722a02818677bcabe57e957f0ce4f841d upstream.

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 <jaewon31.kim@samsung.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm/vmscan.c