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From: Ingo Molnar <mingo@elte.hu>
To: Vince Weaver <vweaver1@eecs.utk.edu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
	linux-kernel@vger.kernel.org, paulus@samba.org, acme@redhat.com,
	torvalds@linux-foundation.org
Subject: Re: perf: definition of a "regression"
Date: Thu, 2 Jun 2011 09:45:30 +0200	[thread overview]
Message-ID: <20110602074530.GF2150@elte.hu> (raw)
In-Reply-To: <alpine.DEB.2.00.1105280918510.27439@cl320.eecs.utk.edu>


* Vince Weaver <vweaver1@eecs.utk.edu> wrote:

> On Sat, 28 May 2011, Peter Zijlstra wrote:
> 
> > On Fri, 2011-05-27 at 23:38 -0400, Vince Weaver wrote:
> > > on that note (and while trying to document exactly what the ioctls do) it 
> > > seems that a PERF_EVENT_IOC_REFRESH with an argument of anything higher 
> > > than one does not work on kernels 2.6.36 and newer.  The behavior acts
> > > as if 1 was passed, even if you pass in, say, 3.
> > 
> > Urgh, no that should definitely work. Thanks for the test-case, I'll
> > work on that (probably not until Monday though, but who knows).
> 
> So wait, the two regressions I found in 2.6.37 are WONTFIX because 
> they are too old, even though they break existing userspace code?
> 
> And this older regression in 2.6.36 is going to be fixed, even 
> though perf, PAPI, and libpfm4 don't trigger the buggy 
> functionality at all?

Btw., these considerations are flexible and we can reconsider and 
change the WONTFIX if there's a patch available and doesn't look 
horrible to backport. We can also mark fixes that havent been marked 
-stable originally as -stable later on, etc.

So please don't feel needlessly bitter about past decisions: when 
there's some good technical solution to a problem (or we were plain 
out wrong about a decision) we try hard not to stand in the way.

Thanks,

	Ingo

  reply	other threads:[~2011-06-02  7:45 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-23 20:04 perf: regression with PERF_EVENT_IOC_REFRESH Vince Weaver
2011-05-23 20:22 ` Peter Zijlstra
2011-05-24  6:20   ` Vince Weaver
2011-05-24 10:30     ` Peter Zijlstra
2011-05-24 15:04       ` Vince Weaver
2011-05-24 15:10         ` Peter Zijlstra
2011-05-24 15:40           ` Ingo Molnar
2011-05-24 20:31             ` Vince Weaver
2011-05-25 10:39               ` Ingo Molnar
2011-05-25 21:24                 ` Vince Weaver
2011-05-24 17:53           ` Vince Weaver
2011-05-24 15:11         ` Peter Zijlstra
2011-05-24 15:18           ` Peter Zijlstra
2011-05-24 21:48             ` Vince Weaver
2011-05-28  3:38       ` Vince Weaver
2011-05-28 10:22         ` Peter Zijlstra
2011-05-28 13:26           ` perf: definition of a "regression" Vince Weaver
2011-06-02  7:45             ` Ingo Molnar [this message]
2011-05-29 16:54           ` perf: regression with PERF_EVENT_IOC_REFRESH Vince Weaver
2011-05-31  1:33             ` perf: [patch] " Vince Weaver
2011-05-31  7:17               ` Peter Zijlstra
2011-05-31  7:23               ` Peter Zijlstra
2011-05-31 13:49                 ` Vince Weaver
2011-05-31 15:52                   ` Peter Zijlstra
2011-05-31 16:39                     ` Vince Weaver

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