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Message-ID: <1321971798.14799.12.camel@twins>
Subject: RE: [PATCH v2 5/5] perf: Enable applicable siblings when group
 leader is enable-on-exec
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: "Zhu, DengCheng" <dczhu@mips.com>
Cc: "Barzilay, Eyal" <eyal@mips.com>, "Fortuna, Zenon" <zenon@mips.com>,
        Paul Mackerras <paulus@samba.org>, Ingo Molnar <mingo@elte.hu>,
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        "ralf@linux-mips.org" <ralf@linux-mips.org>,
        LKML <linux-kernel@vger.kernel.org>
Date: Tue, 22 Nov 2011 15:23:18 +0100
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On Tue, 2011-11-22 at 14:20 +0000, Zhu, DengCheng wrote:
> > @@ -2463,11 +2461,25 @@ static int event_enable_on_exec(struct p
> >        if (event->state >= PERF_EVENT_STATE_INACTIVE)
> >                return 0;
> >
> > -       __perf_event_mark_enabled(event, ctx);
> > +       event->state = PERF_EVENT_STATE_INACTIVE;
> >
> >        return 1;
> >  }
> 
> By simply setting the event state in here, we bypass time stamp stuff as a result.
> This might lead to inaccuracies... 

Ah, but it calls a __perf_event_mark_enabled() at the tail of
group_enable_on_exec() which should fix that up, right?