From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751765AbdG0JKW (ORCPT ); Thu, 27 Jul 2017 05:10:22 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:35821 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751427AbdG0JKU (ORCPT ); Thu, 27 Jul 2017 05:10:20 -0400 From: Michal Hocko To: Andrew Morton Cc: David Rientjes , Johannes Weiner , Roman Gushchin , Tetsuo Handa , , LKML , Michal Hocko Subject: [PATCH 2/2] mm: replace TIF_MEMDIE checks by tsk_is_oom_victim Date: Thu, 27 Jul 2017 11:03:57 +0200 Message-Id: <20170727090357.3205-3-mhocko@kernel.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170727090357.3205-1-mhocko@kernel.org> References: <20170727090357.3205-1-mhocko@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michal Hocko TIF_MEMDIE is set only to the tasks whick were either directly selected by the OOM killer or passed through mark_oom_victim from the allocator path. tsk_is_oom_victim is more generic and allows to identify all tasks (threads) which share the mm with the oom victim. Please note that the freezer still needs to check TIF_MEMDIE because we cannot thaw tasks which do not participage in oom_victims counting otherwise a !TIF_MEMDIE task could interfere after oom_disbale returns. Signed-off-by: Michal Hocko --- kernel/cgroup/cpuset.c | 8 ++++---- mm/memcontrol.c | 2 +- mm/oom_kill.c | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index ca8376e5008c..1cc53dff0d94 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -2497,12 +2497,12 @@ static struct cpuset *nearest_hardwall_ancestor(struct cpuset *cs) * If we're in interrupt, yes, we can always allocate. If @node is set in * current's mems_allowed, yes. If it's not a __GFP_HARDWALL request and this * node is set in the nearest hardwalled cpuset ancestor to current's cpuset, - * yes. If current has access to memory reserves due to TIF_MEMDIE, yes. + * yes. If current has access to memory reserves as an oom victim, yes. * Otherwise, no. * * GFP_USER allocations are marked with the __GFP_HARDWALL bit, * and do not allow allocations outside the current tasks cpuset - * unless the task has been OOM killed as is marked TIF_MEMDIE. + * unless the task has been OOM killed. * GFP_KERNEL allocations are not so marked, so can escape to the * nearest enclosing hardwalled ancestor cpuset. * @@ -2525,7 +2525,7 @@ static struct cpuset *nearest_hardwall_ancestor(struct cpuset *cs) * affect that: * in_interrupt - any node ok (current task context irrelevant) * GFP_ATOMIC - any node ok - * TIF_MEMDIE - any node ok + * tsk_is_oom_victim - any node ok * GFP_KERNEL - any node in enclosing hardwalled cpuset ok * GFP_USER - only nodes in current tasks mems allowed ok. */ @@ -2543,7 +2543,7 @@ bool __cpuset_node_allowed(int node, gfp_t gfp_mask) * Allow tasks that have access to memory reserves because they have * been OOM killed to get memory anywhere. */ - if (unlikely(test_thread_flag(TIF_MEMDIE))) + if (unlikely(tsk_is_oom_victim(current))) return true; if (gfp_mask & __GFP_HARDWALL) /* If hardwall request, stop here */ return false; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 544d47e5cbbd..86a48affb938 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1896,7 +1896,7 @@ static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, * bypass the last charges so that they can exit quickly and * free their memory. */ - if (unlikely(test_thread_flag(TIF_MEMDIE) || + if (unlikely(tsk_is_oom_victim(current) || fatal_signal_pending(current) || current->flags & PF_EXITING)) goto force; diff --git a/mm/oom_kill.c b/mm/oom_kill.c index c9f3569a76c7..65cc2f9aaa05 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -483,7 +483,7 @@ static bool __oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm) * [...] * out_of_memory * select_bad_process - * # no TIF_MEMDIE task selects new victim + * # no TIF_MEMDIE, selects new victim * unmap_page_range # frees some memory */ mutex_lock(&oom_lock); -- 2.13.2