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Date: Tue, 11 May 2010 10:05:57 -0400
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
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Subject: Re: [PATCH 10/10 -v3][RFC] tracing: Combine event filter_active
	and enable into single flags field
Message-ID: <20100511140557.GA29543@Krystal>
References: <20100511030020.837892321@goodmis.org> <20100511030911.927339838@goodmis.org> <20100511033026.GA28162@Krystal> <1273584628.22438.4501.camel@gandalf.stny.rr.com>
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* Steven Rostedt (rostedt@goodmis.org) wrote:
> On Mon, 2010-05-10 at 23:30 -0400, Mathieu Desnoyers wrote:
> > * Steven Rostedt (rostedt@goodmis.org) wrote:
> > > From: Steven Rostedt <srostedt@redhat.com>
> > > 
> > > The filter_active and enable both use an int (4 bytes each) to
> > > set a single flag. We can save 4 bytes per event by combining the
> > > two into a single integer.
> > > 
> 
> > I would also comment about flags read-side:
> > 
> >  * Flags are read concurrently without locking.
> 
> That can go in outside this patch set. As we discussed before, the
> filter_active which does the same today as flags does here also has the
> issue you are concerned with. IOW, this issue has nothing to do with
> this patch set, because the issue existed before the patch set and has
> not changed after the patch set.

That's fine with me.

> 
> The comment should also be in Documentation, not here, since it would
> affect users more than the developers.

Typically, locking-related information belongs to comments close to the
definition. I'm not sure why you say it affects users at all.

Thanks,

Mathieu

> 
> > 
> > Besides that minor nit, the whole patchset has my
> > 
> > Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> 
> Thanks!  I'll get an official release ready.
> 
> -- Steve
> 
> 

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com