From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 0A6386B01CB for ; Wed, 30 Jun 2010 05:30:23 -0400 (EDT) Received: from m3.gw.fujitsu.co.jp ([10.0.50.73]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o5U9UL4d016936 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Wed, 30 Jun 2010 18:30:22 +0900 Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 78BE345DE51 for ; Wed, 30 Jun 2010 18:30:21 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 46BDA45DE4D for ; Wed, 30 Jun 2010 18:30:21 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 21818E18004 for ; Wed, 30 Jun 2010 18:30:21 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.249.87.104]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 9FA2B1DB803E for ; Wed, 30 Jun 2010 18:30:20 +0900 (JST) From: KOSAKI Motohiro Subject: [PATCH 05/11] oom: /proc//oom_score treat kernel thread honestly In-Reply-To: <20100630172430.AA42.A69D9226@jp.fujitsu.com> References: <20100630172430.AA42.A69D9226@jp.fujitsu.com> Message-Id: <20100630182922.AA56.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Wed, 30 Jun 2010 18:30:19 +0900 (JST) Sender: owner-linux-mm@kvack.org To: LKML , linux-mm , Andrew Morton , Minchan Kim , David Rientjes , KAMEZAWA Hiroyuki Cc: kosaki.motohiro@jp.fujitsu.com List-ID: If kernel thread are using use_mm(), badness() return positive value. This is not big issue because caller care it correctly. but there is one exception, /proc//oom_score call badness() directly and don't care the task is regular process. another example, /proc/1/oom_score return !0 value. but it's unkillable. This incorrectness makes confusing to admin a bit. This patch fixes it. Signed-off-by: KOSAKI Motohiro --- fs/proc/base.c | 5 +++-- mm/oom_kill.c | 13 +++++++------ 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 28099a1..56b8d3e 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -428,7 +428,8 @@ static const struct file_operations proc_lstats_operations = { #endif /* The badness from the OOM killer */ -unsigned long badness(struct task_struct *p, unsigned long uptime); +unsigned long badness(struct task_struct *p, struct mem_cgroup *mem, + nodemask_t *nodemask, unsigned long uptime); static int proc_oom_score(struct task_struct *task, char *buffer) { unsigned long points = 0; @@ -437,7 +438,7 @@ static int proc_oom_score(struct task_struct *task, char *buffer) do_posix_clock_monotonic_gettime(&uptime); read_lock(&tasklist_lock); if (pid_alive(task)) - points = badness(task, uptime.tv_sec); + points = badness(task, NULL, NULL, uptime.tv_sec); read_unlock(&tasklist_lock); return sprintf(buffer, "%lu\n", points); } diff --git a/mm/oom_kill.c b/mm/oom_kill.c index ee00817..fcbd21b 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -139,8 +139,8 @@ static bool oom_unkillable_task(struct task_struct *p, struct mem_cgroup *mem, * algorithm has been meticulously tuned to meet the principle * of least surprise ... (be careful when you change it) */ - -unsigned long badness(struct task_struct *p, unsigned long uptime) +unsigned long badness(struct task_struct *p, struct mem_cgroup *mem, + const nodemask_t *nodemask, unsigned long uptime) { unsigned long points, cpu_time, run_time; struct task_struct *child; @@ -150,6 +150,8 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) unsigned long utime; unsigned long stime; + if (oom_unkillable_task(p, mem, nodemask)) + return 0; if (oom_adj == OOM_DISABLE) return 0; @@ -351,7 +353,7 @@ static struct task_struct *select_bad_process(unsigned long *ppoints, if (p->signal->oom_adj == OOM_DISABLE) continue; - points = badness(p, uptime.tv_sec); + points = badness(p, mem, nodemask, uptime.tv_sec); if (points > *ppoints || !chosen) { chosen = p; *ppoints = points; @@ -482,11 +484,10 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, if (child->mm == p->mm) continue; - if (oom_unkillable_task(p, mem, nodemask)) - continue; /* badness() returns 0 if the thread is unkillable */ - child_points = badness(child, uptime.tv_sec); + child_points = badness(child, mem, nodemask, + uptime.tv_sec); if (child_points > victim_points) { victim = child; victim_points = child_points; -- 1.6.5.2 -- 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