From a2816b04ef7430db61bf5ccd5771cfd219fefb05 Mon Sep 17 00:00:00 2001 From: Shakeel Butt Date: Thu, 29 Apr 2021 22:56:08 -0700 Subject: [PATCH] memcg: enable memcg oom-kill for __GFP_NOFAIL In the era of async memcg oom-killer, the commit ef5bb302f2aa ("mm: memcg: do not declare OOM from __GFP_NOFAIL allocations") added the code to skip memcg oom-killer for __GFP_NOFAIL allocations. The reason was that the __GFP_NOFAIL callers will not enter aync oom synchronization path and will keep the task marked as in memcg oom. At that time the tasks marked in memcg oom can bypass the memcg limits and the oom synchronization would have happened later in the later userspace triggered page fault. Thus letting the task marked as under memcg oom bypass the memcg limit for arbitrary time. With the synchronous memcg oom-killer (commit 0a2bdf700e861 ("memcg, oom: move out_of_memory back to the charge path")) and not letting the task marked under memcg oom to bypass the memcg limits (commit 7479cbc972509 ("mm: memcg: do not allow task about to OOM kill to bypass the limit")), we can again allow __GFP_NOFAIL allocations to trigger memcg oom-kill. This will make memcg oom behavior closer to page allocator oom behavior. Link: https://lkml.kernel.org/r/20210223204337.2785120-1-shakeelb@google.com Signed-off-by: Shakeel Butt Acked-by: Michal Hocko Acked-by: Johannes Weiner Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c5ae6a878b8e3..e01602134759a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2779,9 +2779,6 @@ retry: if (gfp_mask & __GFP_RETRY_MAYFAIL) goto nomem; - if (gfp_mask & __GFP_NOFAIL) - goto force; - if (fatal_signal_pending(current)) goto force; -- 2.39.5