From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756812Ab0AOJfh (ORCPT ); Fri, 15 Jan 2010 04:35:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756036Ab0AOJfg (ORCPT ); Fri, 15 Jan 2010 04:35:36 -0500 Received: from casper.infradead.org ([85.118.1.10]:49168 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751001Ab0AOJff (ORCPT ); Fri, 15 Jan 2010 04:35:35 -0500 Subject: Re: [RFC] [PATCH 4/7] Uprobes Implementation From: Peter Zijlstra To: "Frank Ch. Eigler" Cc: Jim Keniston , Arnaldo Carvalho de Melo , Frederic Weisbecker , LKML , Mark Wielaard , utrace-devel In-Reply-To: References: <20100111122521.22050.3654.sendpatchset@srikar.in.ibm.com> <20100111122553.22050.46895.sendpatchset@srikar.in.ibm.com> <1263467394.4244.291.camel@laptop> <1263509380.4875.35.camel@localhost.localdomain> <1263546632.4244.352.camel@laptop> Content-Type: text/plain; charset="UTF-8" Date: Fri, 15 Jan 2010 10:35:24 +0100 Message-ID: <1263548124.4244.358.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2010-01-15 at 04:26 -0500, Frank Ch. Eigler wrote: > Peter Zijlstra writes: > > > [...] > > Right, so all that need be done is add the multiple probe stuff to UBP > > and its a sane interface to use on its own, at which point I'd be > > inclined to call that uprobes (UBP really is an crap name). > > At one point ubp+uprobes were one piece. They were separated on the > suspicion that lkml would like them that way. Right, good thinking, that way we can use ubp without having to use utrace ;-) > > Then we can ditch the whole utrace muck as I see no reason to want to > > use that, whereas the ubp (given a sane name) looks interesting. > > Assuming you meant what you write, perhaps you misunderstand the > layering relationship of these pieces. utrace underlies uprobes and > other process manipulation functionality, present and future. Why, utrace doesn't at all look to bring a fundamental contribution to all that. If there's a proper kernel interface to install probes on userspace code (ubp seems to be mostly that) then I can use perf/ftrace to do the rest of the state management, no need to use utrace there. You can hardly force me to use utrace there, can you?