From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0E7BC433F4 for ; Fri, 24 Aug 2018 23:23:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A292D20836 for ; Fri, 24 Aug 2018 23:23:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A292D20836 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727247AbeHYDAk (ORCPT ); Fri, 24 Aug 2018 23:00:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:33128 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726770AbeHYDAj (ORCPT ); Fri, 24 Aug 2018 23:00:39 -0400 Received: from gandalf.local.home (cpe-66-24-56-78.stny.res.rr.com [66.24.56.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6B3B320836; Fri, 24 Aug 2018 23:23:54 +0000 (UTC) Date: Fri, 24 Aug 2018 19:23:52 -0400 From: Steven Rostedt To: Masami Hiramatsu Cc: Shuah Khan , Ingo Molnar , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 24/32] selftests/ftrace: Add max stack tracer testcase Message-ID: <20180824192352.262144f5@gandalf.local.home> In-Reply-To: <153443763074.23257.4052504725796725062.stgit@devbox> References: <153443695002.23257.13628220023468200991.stgit@devbox> <153443763074.23257.4052504725796725062.stgit@devbox> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 17 Aug 2018 01:40:30 +0900 Masami Hiramatsu wrote: > Add a testcase for max stack tracer, which checks basic > max stack usage tracing and its filter feature. > > Signed-off-by: Masami Hiramatsu > --- > .../ftrace/test.d/ftrace/func_stack_tracer.tc | 39 ++++++++++++++++++++ > 1 file changed, 39 insertions(+) > create mode 100644 tools/testing/selftests/ftrace/test.d/ftrace/func_stack_tracer.tc > > diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_stack_tracer.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_stack_tracer.tc > new file mode 100644 > index 000000000000..b414f0e3c646 > --- /dev/null > +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_stack_tracer.tc > @@ -0,0 +1,39 @@ > +#!/bin/sh > +# SPDX-License-Identifier: GPL-2.0 > +# description: ftrace - Max stack tracer > +# Test the basic function of max-stack usage tracing > + > +if [ ! -f stack_trace ]; then > + echo "Max stack tracer is not supported - please make CONFIG_STACK_TRACER=y" > + exit_unsupported > +fi > + > +echo > stack_trace_filter > +echo 0 > stack_max_size > +echo 1 > /proc/sys/kernel/stack_tracer_enabled > + > +: "Fork and wait for the first entry become !lock" > +timeout=10 > +while [ $timeout -ne 0 ]; do > + ( echo "forked" ) > + FL=`grep " 0)" stack_trace` > + echo $FL | grep -q "lock" || break; > + timeout=$((timeout - 1)) > +done > +echo 0 > /proc/sys/kernel/stack_tracer_enabled > + > +echo '*lock*' > stack_trace_filter > +test `cat stack_trace_filter | wc -l` -eq `grep lock stack_trace_filter | wc -l` > + > +echo 0 > stack_max_size > +echo 1 > /proc/sys/kernel/stack_tracer_enabled This test fails quite a bit because it doesn't guarantee that another stack trace gets in that is bigger, and we don't find the "lock". -- Steve > + > +: "Fork and always the first entry including lock" > +timeout=10 > +while [ $timeout -ne 0 ]; do > + ( echo "forked" ) > + FL=`grep " 0)" stack_trace` > + echo $FL | grep -q "lock" > + timeout=$((timeout - 1)) > +done > +echo 0 > /proc/sys/kernel/stack_tracer_enabled