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Subject: Re: Q: perf_event && event->owner
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
        Alan Stern <stern@rowland.harvard.edu>,
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        linux-kernel@vger.kernel.org
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Date: Tue, 09 Nov 2010 17:56:44 +0100
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On Tue, 2010-11-09 at 16:57 +0100, Oleg Nesterov wrote:
> 
> If the creator of perf_event dies, nobody can use its ->perf_event_list
> anyway. What is the point to keep the reference to the dead task_struct
> and preserve this ->perf_event_list? 

But when the owner dies it will close all its fds, which means it will
clear its tsk->perf_event_list, no? (With exception of the case where
the fd was passed through a unix-socket to another process).