Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965796Ab2EPUOx (ORCPT ); Wed, 16 May 2012 16:14:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34709 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965355Ab2EPUOv (ORCPT ); Wed, 16 May 2012 16:14:51 -0400 Date: Wed, 16 May 2012 16:14:31 -0400 From: Dave Jones To: Arjan van de Ven Cc: Linus Torvalds , Steven Rostedt , LKML , Ingo Molnar , Frederic Weisbecker , David Sharp , Vaibhav Nagarnaik , Peter Zijlstra , Andrew Morton Subject: Re: [RFC][PATCH] tracing: Remove useless 4 bytes of padding from every event Message-ID: <20120516201431.GA29661@redhat.com> Mail-Followup-To: Dave Jones , Arjan van de Ven , Linus Torvalds , Steven Rostedt , LKML , Ingo Molnar , Frederic Weisbecker , David Sharp , Vaibhav Nagarnaik , Peter Zijlstra , Andrew Morton References: <1337175871.6724.46.camel@gandalf.stny.rr.com> <1337198404.6724.81.camel@gandalf.stny.rr.com> <4FB408F2.8060002@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4FB408F2.8060002@linux.intel.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1760 Lines: 37 On Wed, May 16, 2012 at 01:07:14PM -0700, Arjan van de Ven wrote: > On 5/16/2012 1:04 PM, Linus Torvalds wrote: > > On Wed, May 16, 2012 at 1:00 PM, Steven Rostedt wrote: > >> > >> Seriously though. What's your take on changing the kernel that will > >> break an older distro. Obviously, this change is too early to apply. But > >> because an old distro has one app that will break if we make a change in > >> the kernel, is that enough to keep that change out? > > > > I suspect that powertop is enough of a developer thing that if that's > > the only thing that breaks, we don't have to worry too much. > > > > I don't want to break *everybody*, so new distro's should be > > up-to-date. But breaking something like a F14-15 timeframe distro or > > something staid like a SLES (or "Debian Stale" or whatever they call > > that thing that only takes crazy-old binaries)? It's fine. We don't > > want to *rush* into it, but no, if those distros are basically not > > updating, we can't care about them forever for something like > > powertop. > > agreed. > > I would say something like "6 months" (e.g. 3.6); anybody who's likely > to update anything will have done the powertop upgrade from his distro > by then, and anybody who isn't isn't going to update the kernel either. One possibility would be a config symbol to enable the deprecated field (kind of like what we did with compat vdso). Distros that have a new enough powertop can then disable it. Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/