From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753480AbbAUNG1 (ORCPT ); Wed, 21 Jan 2015 08:06:27 -0500 Received: from smtprelay0016.hostedemail.com ([216.40.44.16]:45145 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752008AbbAUNGQ (ORCPT ); Wed, 21 Jan 2015 08:06:16 -0500 X-Session-Marker: 6E657665747340676F6F646D69732E6F7267 X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,rostedt@goodmis.org,:::::::::::::::::::::::::::::,RULES_HIT:41:355:379:541:599:800:960:973:988:989:1260:1277:1311:1313:1314:1345:1359:1437:1515:1516:1518:1534:1539:1593:1594:1711:1730:1747:1777:1792:1981:2194:2199:2393:2553:2559:2562:3138:3139:3140:3141:3142:3352:3622:3865:3867:3868:3870:3871:3872:3874:4250:5007:6261:6742:7875:7903:8660:10004:10400:10848:10967:11026:11232:11658:11914:12050:12114:12438:12517:12519:12740:13069:13148:13230:13311:13357:21080,0,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: stove47_536a629065a51 X-Filterd-Recvd-Size: 2175 Date: Wed, 21 Jan 2015 08:06:12 -0500 From: Steven Rostedt To: Daniel Thompson Cc: Stephen Boyd , Thomas Gleixner , Jason Cooper , Russell King , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, patches@linaro.org, linaro-kernel@lists.linaro.org, John Stultz , Sumit Semwal , Dirk Behme , Daniel Drake , Dmitry Pervushin , Tim Sander Subject: Re: [PATCH 3.19-rc2 v14 0/7] arm: Implement arch_trigger_all_cpu_backtrace Message-ID: <20150121080612.6569ab81@gandalf.local.home> In-Reply-To: <54BF83C9.5060300@linaro.org> References: <1415968543-29469-1-git-send-email-daniel.thompson@linaro.org> <1421144818-14036-1-git-send-email-daniel.thompson@linaro.org> <54BE2D15.9080606@linaro.org> <54BEC04D.1050402@codeaurora.org> <54BF83C9.5060300@linaro.org> 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 On Wed, 21 Jan 2015 10:47:37 +0000 Daniel Thompson wrote: > > With this patchset, is it possible to call sched_clock() from within NMI > > context? I ask because the generic sched_clock() code is not NMI safe That's not good. Better not run function tracing, as that could trace functions in NMI context (I depend on that it does), and it uses sched_clock() as the default clock. -- Steve > > today. We were planning on making it NMI safe by doing something similar > > to what was done for ktime_get_mono_fast_ns() but we haven't gotten > > around to it. Mostly because no architecture that uses generic > > sched_clock() has support for NMIs right now. >