Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754834AbbFLN2i (ORCPT ); Fri, 12 Jun 2015 09:28:38 -0400 Received: from foss.arm.com ([217.140.101.70]:58647 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752220AbbFLN2h (ORCPT ); Fri, 12 Jun 2015 09:28:37 -0400 Message-ID: <1434115713.1484.9.camel@arm.com> Subject: Re: [RFC PATCH] perf: Add PERF_RECORD_SWITCH to indicate context switches From: Pawel Moll To: Adrian Hunter Cc: Arnaldo Carvalho de Melo , Peter Zijlstra , Andi Kleen , Ingo Molnar , "linux-kernel@vger.kernel.org" , Jiri Olsa , Stephane Eranian , "mathieu.poirier@linaro.org" Date: Fri, 12 Jun 2015 14:28:33 +0100 In-Reply-To: <557ADB6E.8080604@intel.com> References: <1433859670-10806-1-git-send-email-adrian.hunter@intel.com> <20150611141548.GW19282@twins.programming.kicks-ass.net> <557ABE8B.1020705@intel.com> <20150612120938.GS3644@twins.programming.kicks-ass.net> <20150612123643.GA6850@kernel.org> <557ADB6E.8080604@intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.10-0ubuntu1~14.10.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1171 Lines: 27 On Fri, 2015-06-12 at 14:15 +0100, Adrian Hunter wrote: > >>>> all 3 are already part of sample_id. > >>> > >>> You have to decide whether you expect to be able to use an event without > >>> sample_id. MMAP and MMAP2 both have pid, tid which are in sample_id, LOST > >>> has id, EXIT and FORK have time, all of the THROTTLE/UNTHROTTLE members are > >>> in sample_id etc. So it currently looks like we expect to be able to use an > >>> event without requiring sample_id. > > > > The fact that there is this duplication is because sample_id_all came > > after those events, but this new one being proposed doesn't have to do > > it :-) > > Thanks, that's clear then. There will just need to be a flag to indicate > whether it is scheduling in or out. Just a thought: wouldn't it be good to know what CPU have we been scheduled from/to? This kind of information would be especially valuable in heterogeneous systems. Pawel -- 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/