From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751891Ab1GENtc (ORCPT ); Tue, 5 Jul 2011 09:49:32 -0400 Received: from mail-vx0-f174.google.com ([209.85.220.174]:50714 "EHLO mail-vx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751093Ab1GENtb (ORCPT ); Tue, 5 Jul 2011 09:49:31 -0400 Date: Tue, 5 Jul 2011 15:49:25 +0200 From: Frederic Weisbecker To: "K.Prasad" Cc: Ingo Molnar , Paul Mundt , linuxppc-dev@lists.ozlabs.org, LKML , Peter Zijlstra Subject: Re: [PATCH 2/6] hw_breakpoints: Migrate breakpoint conditional build under new config Message-ID: <20110705134920.GF5551@somewhere> References: <1306273947-8410-1-git-send-email-fweisbec@gmail.com> <1306273947-8410-3-git-send-email-fweisbec@gmail.com> <20110704132746.GA2963@in.ibm.com> <20110704132912.GB5551@somewhere> <20110704174416.GA2166@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110704174416.GA2166@in.ibm.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 On Mon, Jul 04, 2011 at 11:14:16PM +0530, K.Prasad wrote: > On Mon, Jul 04, 2011 at 03:29:14PM +0200, Frederic Weisbecker wrote: > > On Mon, Jul 04, 2011 at 06:57:46PM +0530, K.Prasad wrote: > > > On Tue, May 24, 2011 at 11:52:23PM +0200, Frederic Weisbecker wrote: > > > > Migrate conditional hw_breakpoint code compilation under > > > > the new config to prepare for letting the user chose whether > > > > or not to build this feature > > > > > > > > > > Making the hardware breakpoint patches modular has always been a goal. > > > I've looked at the PowerPC parts of the code and they look harmless. > > > > > > Acked-by: K.Prasad > > > > Great! > > > > I'll push that soon, thanks guys for your acks! > > Meanwhile, I was testing hardware breakpoints through perf and found > that monitoring a given address fails when using 'perf record' (returns > -ENOSPC) while 'perf stat' and watchpoint through gdb works fine (see > logs below). > > Has this behaviour been reported for other perf counters? Nope I haven't anything like that. What I reported privately to you a few ago was actually due to a mistake of mine. Otherwise I haven't seen other problems. -ENOSPC is likely related to the breakpoint slot reservation, in kernel/events/hw_breakpoint.c