Date: Tue, 23 Jul 2013 18:57:39 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Andi Kleen <andi@firstfloor.org>
Cc: mingo@kernel.org, linux-kernel@vger.kernel.org,
        Andi Kleen <ak@linux.intel.com>, eranian@google.com
Subject: Re: [PATCH] perf, x86: Enable PEBS mode automatically for
 mem-{loads,stores} v3
Message-ID: <20130723165739.GD27075@twins.programming.kicks-ass.net>
References: <1374188619-19220-1-git-send-email-andi@firstfloor.org>
 <20130723083834.GS27075@twins.programming.kicks-ass.net>
 <20130723161334.GQ6123@two.firstfloor.org>
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On Tue, Jul 23, 2013 at 06:13:34PM +0200, Andi Kleen wrote:
> On Tue, Jul 23, 2013 at 10:38:34AM +0200, Peter Zijlstra wrote:
> > On Thu, Jul 18, 2013 at 04:03:39PM -0700, Andi Kleen wrote:
> > > From: Andi Kleen <ak@linux.intel.com>
> > > 
> > > [The patch to enable this in the user tools has been sent separately]
> > > 
> > > With the earlier patches to automatically try cpu// and add
> > > a precise sys attribute, we can now enable PEBS for the mem-loads,
> > > mem-stores events everywhere.
> > > 
> > > This allows to use
> > > 
> > > perf record -e mem-loads ...
> > > 
> > > instead of
> > > 
> > > perf record -e cpu/mem-loads/p ...
> > > 
> > > Always use precise=2 even though it is costly pre-Haswell
> > 
> > This Changelog fails to give a reason _why_ we'd want to do this.
> 
> The first is much nicer to type and understand? Just in the spirit of
> making perf easier to use.

And here I was thinking that maybe these events don't make sense without
pebs or so. But no, rather than giving an actual useful reason you'd
have me look things up myself. *sigh*
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