From 4942642080ea82d99ab5b653abb9a12b7ba31f4a Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Wed, 16 Oct 2013 13:46:59 -0700 Subject: mm: memcg: handle non-error OOM situations more gracefully Commit 3812c8c8f395 ("mm: memcg: do not trap chargers with full callstack on OOM") assumed that only a few places that can trigger a memcg OOM situation do not return VM_FAULT_OOM, like optional page cache readahead. But there are many more and it's impractical to annotate them all. First of all, we don't want to invoke the OOM killer when the failed allocation is gracefully handled, so defer the actual kill to the end of the fault handling as well. This simplifies the code quite a bit for added bonus. Second, since a failed allocation might not be the abrupt end of the fault, the memcg OOM handler needs to be re-entrant until the fault finishes for subsequent allocation attempts. If an allocation is attempted after the task already OOMed, allow it to bypass the limit so that it can quickly finish the fault and invoke the OOM killer. Reported-by: azurIt Signed-off-by: Johannes Weiner Cc: Michal Hocko Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/oom_kill.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/oom_kill.c') diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 314e9d274381..6738c47f1f72 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -680,7 +680,7 @@ void pagefault_out_of_memory(void) { struct zonelist *zonelist; - if (mem_cgroup_oom_synchronize()) + if (mem_cgroup_oom_synchronize(true)) return; zonelist = node_zonelist(first_online_node, GFP_KERNEL); -- cgit v1.2.3-59-g8ed1b