From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756550AbYLPMW4 (ORCPT ); Tue, 16 Dec 2008 07:22:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751730AbYLPMWr (ORCPT ); Tue, 16 Dec 2008 07:22:47 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:42956 "EHLO gprs189-60.eurotel.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751302AbYLPMWr (ORCPT ); Tue, 16 Dec 2008 07:22:47 -0500 Date: Tue, 16 Dec 2008 13:22:29 +0100 From: Pavel Machek To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Thomas Gleixner , Andrew Morton , Stephane Eranian , Eric Dumazet , Robert Richter , Arjan van de Ven , Peter Anvin , Peter Zijlstra , Paul Mackerras , "David S. Miller" , perfctr-devel@lists.sourceforge.net Subject: Re: [patch] Performance Counters for Linux, v4 Message-ID: <20081216122229.GA1430@ucw.cz> References: <20081214212829.GA9435@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081214212829.GA9435@elte.hu> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun 2008-12-14 22:28:29, Ingo Molnar wrote: > We are pleased to announce the v4 release of our performance counters > subsystem implementation. The kernel changes can be picked up from: > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git perfcounters/core > > (also in the master branch. There's also a kernel patch attached > below.) > > The biggest new feature in this release is the implementation of > "performance counter inheritance" for the per task counters: the ability > to extend performance counters to cover the execution of child tasks > too, transparently and automatically - following them to other CPUs. > > This can be used to monitor a hierarchy of tasks without stopping them > (or impacting them in any observable way), and extending that monitoring > to all child tasks as well. > > We've written a new utility: 'timec', which takes advantage of this new > kernel capability: > > http://redhat.com/~mingo/perfcounters/timec.c > > 'timec' works like /usr/bin/time, but it extends the dimension of "time" > with all the metrics that hardware and software performance counters are > able to capture. Hmm, if I timec some setuid program, what happens? Performance counters seem like great tool to pull secret keys out of other processes :-). Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html