path: root/mm
diff options
authorTetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>2016-02-05 15:36:30 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-02-05 18:10:40 -0800
commit564e81a57f9788b1475127012e0fd44e9049e342 (patch)
tree6ed99c6e46c2133dc7ca7eb085a3f1a43407763a /mm
parentccde8bd4014eb2f01102f7a64f0fad3df193b758 (diff)
mm, vmstat: fix wrong WQ sleep when memory reclaim doesn't make any progress
Jan Stancek has reported that system occasionally hanging after "oom01" testcase from LTP triggers OOM. Guessing from a result that there is a kworker thread doing memory allocation and the values between "Node 0 Normal free:" and "Node 0 Normal:" differs when hanging, vmstat is not up-to-date for some reason. According to commit 373ccbe59270 ("mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress"), it meant to force the kworker thread to take a short sleep, but it by error used schedule_timeout(1). We missed that schedule_timeout() in state TASK_RUNNING doesn't do anything. Fix it by using schedule_timeout_uninterruptible(1) which forces the kworker thread to take a short sleep in order to make sure that vmstat is up-to-date. Fixes: 373ccbe59270 ("mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress") Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: Jan Stancek <jstancek@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Tejun Heo <tj@kernel.org> Cc: Cristopher Lameter <clameter@sgi.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Arkadiusz Miskiewicz <arekm@maven.pl> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index cc5d29d2da9b..926c76d56388 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -989,7 +989,7 @@ long wait_iff_congested(struct zone *zone, int sync, long timeout)
* here rather than calling cond_resched().
if (current->flags & PF_WQ_WORKER)
- schedule_timeout(1);
+ schedule_timeout_uninterruptible(1);