From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1756603Ab2LMQ7L (ORCPT <rfc822;w@1wt.eu>);
	Thu, 13 Dec 2012 11:59:11 -0500
Received: from mail-bk0-f46.google.com ([209.85.214.46]:55080 "EHLO
	mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1753702Ab2LMQ7J (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Thu, 13 Dec 2012 11:59:09 -0500
Date: Thu, 13 Dec 2012 17:59:04 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [GIT PULL] perf changes for v3.8
Message-ID: <20121213165904.GA18574@gmail.com>
References: <50C94A9C.2050900@gmail.com>
 <CA+55aFxpLJ=gVUSiu04sTzDDrR75B89pzE35MyEyj3pVi5UbiQ@mail.gmail.com>
 <50C94ECD.6020504@gmail.com>
 <CA+55aFzmsEbKCg=Qp0LGxQb-D+ZfBAELEa4HyUkuxkj6Z0-agA@mail.gmail.com>
 <50C95A21.1010101@gmail.com>
 <20121213073056.GA13156@gmail.com>
 <50C9E692.9070506@gmail.com>
 <CA+55aFzmDooC3tYzvP1YGv9g4ej1hBUQBPV6R+ukrfxuEELBaQ@mail.gmail.com>
 <50CA0134.2090608@gmail.com>
 <CA+55aFyZ2kAQPmZSv_sfHDAR1gusOxO22TRX-kqSim-cZrMscw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CA+55aFyZ2kAQPmZSv_sfHDAR1gusOxO22TRX-kqSim-cZrMscw@mail.gmail.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org


* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> > I could write the patch to completely invert the 
> > exclude_guest logic -- make it include_guest. That breaks 
> > all existing perf binaries as well - just a different syntax 
> > that gets broken. That regression is acceptable?
> 
> It's not a regression since THAT CODE NEVER WORKED, for 
> chissake! The case of people actually profiling into virtual 
> machines crashes the running VMs, as you say. There's no way 
> in hell we can call it a regression to say "you now have to 
> use a flag if you profile a load with virtualization", since 
> there wasn't any working case to begin with.

Correct.

::include_guest looks like the more logical flag direction to
use in any case.

Thanks,

	Ingo