Message-ID: <557A28F6.8040603@gmail.com>
Date: Thu, 11 Jun 2015 18:33:58 -0600
From: David Ahern <dsahern@gmail.com>
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To: Andi Kleen <andi@firstfloor.org>
CC: Arnaldo Carvalho de Melo <acme@kernel.org>, kan.liang@intel.com,
        linux-kernel@vger.kernel.org, ying.huang@intel.com
Subject: Re: [PATCH 1/1] perf,tools: add time out to force stop endless mmap
 processing
References: <1433922364-22580-1-git-send-email-kan.liang@intel.com> <20150611140614.GC2696@kernel.org> <5579A766.4010504@gmail.com> <20150611184737.GU19417@two.firstfloor.org>
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On 6/11/15 12:47 PM, Andi Kleen wrote:
>> Can you elaborate on an example? I don't see how this can happen
>> reading a maps file. And it does not read maps for all threads only
>> thread group leaders.
>
> This is with a stress test case that generates lots of small mappings
> at very high speed and frees them again. So the maps file keeps changing
> faster than the proc reader can keep it and it can end up with
> a live lock.

Can you pass it along? I'd like to see how the task_diag proposal 
handles it.

https://github.com/dsahern/linux/commits/task_diag-wip
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