Re: [PATCH] mm,oom: Warn on racing with MMF_OOM_SKIP at task_will_free_mem(current).
From: Michal Hocko <mhocko@suse.com>
Date: 2017-09-26 11:39:56
On Tue 26-09-17 20:27:40, Tetsuo Handa wrote: [...]
quoted hunk ↗ jump to hunk
@@ -794,8 +794,10 @@ static bool task_will_free_mem(struct task_struct *task) * This task has already been drained by the oom reaper so there are * only small chances it will free some more */ - if (test_bit(MMF_OOM_SKIP, &mm->flags)) + if (test_bit(MMF_OOM_SKIP, &mm->flags)) { + WARN(1, "Racing OOM victim selection. Please report to linux-mm@kvack.org if you saw this warning from non-artificial workloads.\n"); return false; + }
This can easily happen even without a race. Just consider that OOM memory reserves got depleted. I think that the existing oom report will tell us that the race happened by checking the mm counters. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>