From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934818AbdIYKwg (ORCPT ); Mon, 25 Sep 2017 06:52:36 -0400 Received: from smtprelay0154.hostedemail.com ([216.40.44.154]:34285 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S934668AbdIYKwf (ORCPT ); Mon, 25 Sep 2017 06:52:35 -0400 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,rostedt@goodmis.org,:::::::,RULES_HIT:41:355:379:541:599:800:960:973:988:989:1260:1277:1311:1313:1314:1345:1359:1437:1515:1516:1518:1534:1540:1593:1594:1711:1730:1747:1777:1792:2393:2553:2559:2562:2890:3138:3139:3140:3141:3142:3352:3622:3865:3866:3867:3868:3871:3873:3874:5007:6119:6261:7875:7903:8660:10004:10400:10848:10967:11232:11658:11914:12740:12760:12895:13069:13138:13148:13230:13231:13255:13311:13357:13439:14096:14097:14181:14659:14721:21080:21450:21627:30054:30090:30091,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:2,LUA_SUMMARY:none X-HE-Tag: cord75_6d8d01a593246 X-Filterd-Recvd-Size: 2101 Date: Mon, 25 Sep 2017 06:52:26 -0400 From: Steven Rostedt To: Peter Zijlstra Cc: Joel Fernandes , LKML , kernel-team@android.com Subject: Re: [PATCH v6 2/2] tracing: Add support for preempt and irq enable/disable events Message-ID: <20170925065226.137ec45e@vmware.local.home> In-Reply-To: <20170925103223.horr6amiunw6if3n@hirez.programming.kicks-ass.net> References: <20170922015024.16123-1-joelaf@google.com> <20170922015024.16123-3-joelaf@google.com> <20170922090229.rdicci6emtyffqdn@hirez.programming.kicks-ass.net> <20170925083432.jvaewlsrb46wjmjj@hirez.programming.kicks-ass.net> <20170925061528.09082957@vmware.local.home> <20170925103223.horr6amiunw6if3n@hirez.programming.kicks-ass.net> X-Mailer: Claws Mail 3.15.0-dirty (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 25 Sep 2017 12:32:23 +0200 Peter Zijlstra wrote: > > You mean you want to trace all calls to preempt and irq off even if > > preempt and irqs are already off? > > Sure, why not? This stuff naturally nests, and who is to say its not a > useful thing to trace all of them? > > By also tracing the nested sections you can, for instance, see how much > you'd really win by getting rid of the outer one. If, for instance, the > outer only accounts for 1% of the time, while the inner ones are > interlinked and span the other 99%, there's more work to do than if that > were not the case. If we do this we need a field to record if the preemption or irqs were toggled by that call. Something that filters could easily be added to only show what this patch set has. -- Steve