From patchwork Thu Oct 10 20:52:35 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13831101 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CB0781CF7B8; Thu, 10 Oct 2024 20:52:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728593548; cv=none; b=KPsSWZSDlhwoj5pjieRj+NSSasSvfSi81rxc+fEMEFm0EC+EVS7p3FruMN6Vk2BYeALkKPCxvRwJ9n7By8ZppdHQ+LDzl7svguln7XG5ynzniqAiCxsi6SIiZKlbqrqtst21nHeQE5f/9egpbCNDqRcpIH8clvtbFa792KBm7BQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728593548; c=relaxed/simple; bh=VOLSGxoFpqEKw8p69LGCSzYyDXmPRCffVpLrGBu5v+s=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type; b=JGwNvuZ7Vn2v7XGHvy/hipdJovS4kb0W0LGHI2mmiHsR9saylRUVOlx79C9ynqArFoaOQNNfFcTqU7ZmLDohfShDJBu/ITCok3VvCtuM7sCL1ynEDgqekxC3wrlWh3AndVFeB9JWw6zFpsVSnocayIxgv0d0dsNW2K/lsWO3OOU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93E1EC4CEC5; Thu, 10 Oct 2024 20:52:27 +0000 (UTC) Date: Thu, 10 Oct 2024 16:52:35 -0400 From: Steven Rostedt To: LKML , Linux Trace Kernel , linux-kselftest@vger.kernel.org Cc: Shuah Khan , Masami Hiramatsu , Mathieu Desnoyers Subject: [PATCH v3] ftrace/selftest: Test combination of function_graph tracer and function profiler Message-ID: <20241010165235.35122877@gandalf.local.home> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Steven Rostedt Masami reported a bug when running function graph tracing then the function profiler. The following commands would cause a kernel crash: # cd /sys/kernel/tracing/ # echo function_graph > current_tracer # echo 1 > function_profile_enabled In that order. Create a test to test this two to make sure this does not come back as a regression. Link: https://lore.kernel.org/172398528350.293426.8347220120333730248.stgit@devnote2 Acked-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) --- Changes since v2: https://lore.kernel.org/20241004145618.18436d7e@gandalf.local.home - Fixed grammar of comment .../ftrace/test.d/ftrace/fgraph-profiler.tc | 31 +++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 tools/testing/selftests/ftrace/test.d/ftrace/fgraph-profiler.tc diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-profiler.tc b/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-profiler.tc new file mode 100644 index 000000000000..ffff8646733c --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-profiler.tc @@ -0,0 +1,31 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: ftrace - function profiler with function graph tracing +# requires: function_profile_enabled set_ftrace_filter function_graph:tracer + +# The function graph tracer can now be run along side of the function +# profiler. But there was a bug that caused the combination of the two +# to crash. It also required the function graph tracer to be started +# first. +# +# This test triggers that bug +# +# We need both function_graph and profiling to run this test + +fail() { # mesg + echo $1 + exit_fail +} + +echo "Enabling function graph tracer:" +echo function_graph > current_tracer +echo "enable profiler" + +# Older kernels do not allow function_profile to be enabled with +# function graph tracer. If the below fails, mark it as unsupported +echo 1 > function_profile_enabled || exit_unsupported + +# Let it run for a bit to make sure nothing explodes +sleep 1 + +exit 0