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Date: Tue, 5 Sep 2017 13:19:43 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
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        linux-kernel <linux-kernel@vger.kernel.org>,
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Subject: Re: [RFC][PATCH] perf: Rewrite enabled/running timekeeping
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On Tue, Sep 05, 2017 at 01:17:39PM +0300, Alexey Budankov wrote:
> However we can't completely get rid of whole tree iterations because of 
> inheritance code on forks in perf_event_init_context() here:

Right, fork() / inherit needs to iterate the full thing, nothing to be
done about that.

I'll go make proper patches for that timekeeping rewrite and then have a
look at your patches.