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From: Peter Zijlstra <peterz@infradead.org>
To: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Paul Mackerras <paulus@samba.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] perf/sched: fix for getting task's execute time
Date: Sun, 06 Dec 2009 12:05:12 +0100	[thread overview]
Message-ID: <1260097512.7818.341.camel@laptop> (raw)
In-Reply-To: <4B1B8E0E.3040007@cn.fujitsu.com>

On Sun, 2009-12-06 at 18:57 +0800, Xiao Guangrong wrote:
> In current code, we get task's execute time by reading
> "/proc/<pid>/sched" file, it's wrong if the task is created
> by pthread_create(), because every thread task has same pid.
> So, the correct way is reading "/proc/<ppid>/task/<tid>/sched"
> file.
> 
> This patch also remove redundant include files since <sys/types.h>
> is included in "perf.h"

We really should not be using these proc files but instead make sure
this information gets transferred through a tracepoint or similar.

Reading these proc files is too prone to races.



  reply	other threads:[~2009-12-06 11:05 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-06 10:57 [PATCH] perf/sched: fix for getting task's execute time Xiao Guangrong
2009-12-06 11:05 ` Peter Zijlstra [this message]
2009-12-06 11:06   ` Peter Zijlstra
2009-12-06 11:50     ` Ingo Molnar
2009-12-06 17:10     ` Xiao Guangrong
2009-12-07  7:20       ` [PATCH v2] perf/sched: fix for getting task's execution time Xiao Guangrong
2009-12-07  7:30         ` Ingo Molnar
2009-12-09  9:51           ` [PATCH v3] " Xiao Guangrong
2009-12-09  9:54             ` Xiao Guangrong
2009-12-09  9:59               ` Ingo Molnar
2009-12-09  9:57             ` Xiao Guangrong
2009-12-09  9:57             ` Ingo Molnar
2009-12-09 10:03             ` [tip:perf/urgent] perf sched: Fix " tip-bot for Xiao Guangrong

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