Date: Thu, 11 Jun 2015 20:47:37 +0200
From: Andi Kleen <andi@firstfloor.org>
To: David Ahern <dsahern@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>, kan.liang@intel.com,
        linux-kernel@vger.kernel.org, ying.huang@intel.com,
        andi@firstfloor.org
Subject: Re: [PATCH 1/1] perf,tools: add time out to force stop endless mmap
 processing
Message-ID: <20150611184737.GU19417@two.firstfloor.org>
References: <1433922364-22580-1-git-send-email-kan.liang@intel.com>
 <20150611140614.GC2696@kernel.org>
 <5579A766.4010504@gmail.com>
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> 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.

-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.
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