From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yk0-f176.google.com (mail-yk0-f176.google.com [209.85.160.176]) by kanga.kvack.org (Postfix) with ESMTP id 235B56B0253 for ; Wed, 26 Aug 2015 08:20:17 -0400 (EDT) Received: by ykdt205 with SMTP id t205so185360877ykd.1 for ; Wed, 26 Aug 2015 05:20:16 -0700 (PDT) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [2001:e42:101:1:202:181:97:72]) by mx.google.com with ESMTPS id r19si38300555qha.4.2015.08.26.05.20.15 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 26 Aug 2015 05:20:15 -0700 (PDT) Subject: [PATCH 2/2] android, lmk: Reverse the order of setting TIF_MEMDIE and sending SIGKILL. From: Tetsuo Handa References: <201508262117.FAH43726.tOFMVJSLQOFHFO@I-love.SAKURA.ne.jp> In-Reply-To: <201508262117.FAH43726.tOFMVJSLQOFHFO@I-love.SAKURA.ne.jp> Message-Id: <201508262119.IHA93770.JOOtFHMSFLOQVF@I-love.SAKURA.ne.jp> Date: Wed, 26 Aug 2015 21:19:48 +0900 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org List-ID: To: gregkh@linuxfoundation.org, arve@android.com, riandrews@android.com Cc: devel@driverdev.osuosl.org, linux-mm@kvack.org, mhocko@kernel.org, rientjes@google.com, hannes@cmpxchg.org Hello. Should selected_tasksize be added to rem even when TIF_MEMDIE was not set? Please see a thread from http://www.spinics.net/lists/linux-mm/msg93246.html if you want to know why to reverse the order. ---------------------------------------- >>From 2d4cc11d8128e4c1397631b91fea78da3eaefb47 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Wed, 26 Aug 2015 20:52:39 +0900 Subject: [PATCH 2/2] android, lmk: Reverse the order of setting TIF_MEMDIE and sending SIGKILL. If we set TIF_MEMDIE before sending SIGKILL, memory reserves could be spent for allocations which are not needed for terminating the victim. Reverse the order as with oom_kill_process() does. Signed-off-by: Tetsuo Handa --- drivers/staging/android/lowmemorykiller.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/drivers/staging/android/lowmemorykiller.c b/drivers/staging/android/lowmemorykiller.c index d5d25e4..c39b6a2 100644 --- a/drivers/staging/android/lowmemorykiller.c +++ b/drivers/staging/android/lowmemorykiller.c @@ -156,26 +156,24 @@ next: } if (selected) { task_lock(selected); - if (!selected->mm) { - /* Already exited, cannot do mark_tsk_oom_victim() */ - task_unlock(selected); - goto out; - } + lowmem_print(1, "send sigkill to %d (%s), adj %hd, size %d\n", + selected->pid, selected->comm, + selected_oom_score_adj, selected_tasksize); + task_unlock(selected); + send_sig(SIGKILL, selected, 0); /* * FIXME: lowmemorykiller shouldn't abuse global OOM killer * infrastructure. There is no real reason why the selected * task should have access to the memory reserves. */ - mark_oom_victim(selected); - lowmem_print(1, "send sigkill to %d (%s), adj %hd, size %d\n", - selected->pid, selected->comm, - selected_oom_score_adj, selected_tasksize); + task_lock(selected); + if (selected->mm) { + mark_oom_victim(selected); + lowmem_deathpending_timeout = jiffies + HZ; + rem += selected_tasksize; + } task_unlock(selected); - lowmem_deathpending_timeout = jiffies + HZ; - send_sig(SIGKILL, selected, 0); - rem += selected_tasksize; } -out: lowmem_print(4, "lowmem_scan %lu, %x, return %lu\n", sc->nr_to_scan, sc->gfp_mask, rem); rcu_read_unlock(); -- 1.8.3.1 -- 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: email@kvack.org