Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754775Ab0ATGP7 (ORCPT ); Wed, 20 Jan 2010 01:15:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752740Ab0ATGP5 (ORCPT ); Wed, 20 Jan 2010 01:15:57 -0500 Received: from e5.ny.us.ibm.com ([32.97.182.145]:43687 "EHLO e5.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751318Ab0ATGP4 (ORCPT ); Wed, 20 Jan 2010 01:15:56 -0500 Date: Wed, 20 Jan 2010 11:45:51 +0530 From: Ananth N Mavinakayanahalli To: Ingo Molnar Cc: Stephen Rothwell , Peter Zijlstra , Peter Zijlstra , Fr??d??ric Weisbecker , LKML , Steven Rostedt , Arnaldo Carvalho de Melo , "Frank Ch. Eigler" , linux-next@vger.kernel.org, "H. Peter Anvin" , utrace-devel@redhat.com, Thomas Gleixner , Linus Subject: Re: linux-next: add utrace tree Message-ID: <20100120061551.GB6588@in.ibm.com> Reply-To: ananth@in.ibm.com References: <20100119211646.GF16096@redhat.com> <20100120111220.e7fb4e2c.sfr@canb.auug.org.au> <20100120054950.GB27108@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100120054950.GB27108@elte.hu> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1942 Lines: 48 On Wed, Jan 20, 2010 at 06:49:50AM +0100, Ingo Molnar wrote: Ingo, > Note, i'm not yet convinced that this (and the rest: uprobes and systemtap, > etc.) can go uptream in its present form. Agreed, uprobes is still not upstream ready -- it was an RFC. We are working through the comments there to get it ready for merger. > IMHO the far more important thing to address beyond formalities and workflow > cleanliness are the (many) technical observations and objections offered by > Peter Zijstra on lkml. Not just the git history but also the abstractions and > concepts are messy and should be reworked IMO, and also good and working perf > events integration should be achieved, etc. I think Oleg addressed most of Peter's concerns on utrace when the ptrace/utrace patchset was reposted. Perf integration with uprobes will be done and discussions have started with Masami and Frederic. There are a couple of fundamental technical aspects (XOL vma vs. emulation; breakpoint insertion through CoW and not through quiesce) that need resolution. > The fact that there's a well established upstream workflow for instrumentation > patches, which is being routed around by the utrace/uprobes/systemtap code > here is not a good sign in terms of reaching a good upstream solution. Lets > hope it works out well though. Agreed. On the other hand, having ptrace/utrace in the -next tree will give it a lot more testing, while any outstanding technical issues are being addressed. Stephen, To exercise ptrace/utrace, it would be very useful if you pulled in git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-utrace.git branch utrace-ptrace instead of 'master'. Thanks, Ananth -- 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/