Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933722AbbFJTQD (ORCPT ); Wed, 10 Jun 2015 15:16:03 -0400 Received: from smtprelay0031.hostedemail.com ([216.40.44.31]:56978 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932757AbbFJTPz (ORCPT ); Wed, 10 Jun 2015 15:15:55 -0400 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,rostedt@goodmis.org,:::::::::,RULES_HIT:41:355:379:541:599:800:960:973:982:988:989:1260:1277:1311:1313:1314:1345:1359:1437:1515:1516:1518:1534:1541:1593:1594:1711:1730:1747:1777:1792:2393:2553:2559:2562:2892:3138:3139:3140:3141:3142:3352:3622:3865:3866:3867:3868:3870:3871:3872:3873:3874:4321:4559:4605:5007:6117:6119:6261:7875:10004:10226:10400:10848:10967:11026:11232:11658:11914:12043:12517:12519:12555:12740:13069:13311:13357:21080,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:none,Custom_rules:0:0:0 X-HE-Tag: trail48_6db64bb6f1423 X-Filterd-Recvd-Size: 2309 Date: Wed, 10 Jun 2015 15:15:51 -0400 From: Steven Rostedt To: Thomas Gleixner Cc: Mike Galbraith , LKML , Peter Zijlstra , Ingo Molnar Subject: Re: RFC: futex_wait() can DoS the tick Message-ID: <20150610151551.3cfc616a@gandalf.local.home> In-Reply-To: References: <1433940278.6814.66.camel@gmail.com> <1433957421.6306.28.camel@gmail.com> X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.25; 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 Content-Length: 1512 Lines: 37 On Wed, 10 Jun 2015 20:59:49 +0200 (CEST) Thomas Gleixner wrote: > On Wed, 10 Jun 2015, Mike Galbraith wrote: > > > On Wed, 2015-06-10 at 17:12 +0200, Thomas Gleixner wrote: > > > > > Some more information about your symptoms in form of configuration, > > > extra patches, kernel traces etc. would be appreciated. > > > > homer:~/tmp # perf record -C 3 -eirq:*,irq_vectors:local* -- sleep 10 I would recommend using trace-cmd especially if you add function tracing, as it's made more for fast tracing. -- Steve > > [ perf record: Woken up 2 times to write data ] > > [ perf record: Captured and wrote 1380.507 MB perf.data (19530595 samples) ] > > homer:~/tmp # perf script | grep irq_vectors:local_timer > > ksoftirqd/3 19 [003] 5586.564238: irq_vectors:local_timer_entry: vector=239 > > ksoftirqd/3 19 [003] 5586.564239: irq_vectors:local_timer_exit: vector=239 > > ksoftirqd/3 19 [003] 5586.568238: irq_vectors:local_timer_entry: vector=239 > > ksoftirqd/3 19 [003] 5586.568239: irq_vectors:local_timer_exit: vector=239 > > ksoftirqd/3 19 [003] 5586.632218: irq_vectors:local_timer_entry: vector=239 > > That gap is odd. Can you fire up the function tracer please? > > Thanks, > > tglx -- 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/