From patchwork Wed Mar 20 14:18:44 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Rutland X-Patchwork-Id: 781972 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E57D441C84; Wed, 20 Mar 2024 14:18:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710944333; cv=none; b=CJ3tVQCUX5g9mjX3eV/tOpy/62zvaC7T+fNmigz8vpN7IazA04OndL0hdvKEI0KRV7eksy0gZss6TwmPukHdnea3NLvRiSS85C2JDTiP9YyMTLEJNXLpZ3ctPFFbNjfzObfv0R4+YDB+HAco6xWzemZEXk9DrCpJ3/sfOY+CuCg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710944333; c=relaxed/simple; bh=xmbyWobTD3RpSNLREBva1eUC9VLaDy7wqoqKn/PRejE=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=dBgKnOlnK4DJO4uifxKkt4ak+4RnA+Ege+o3eu9EJMHjbTl8zDhZBX9cFoIyA2LEl9jYxmGPhp+CU53C0K8/ZT/OwFBL5D349yCFnksErOUu/LQSOjewGegWl0DDpSPLndbQLUC9H07x1h3gfortN7Oyj9rk+peszvIGAfPk7PE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BFD591007; Wed, 20 Mar 2024 07:19:25 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 8F3253F64C; Wed, 20 Mar 2024 07:18:49 -0700 (PDT) From: Mark Rutland To: linux-kernel@vger.kernel.org Cc: aishwarya.tcv@arm.com, linux-kselftest@vger.kernel.org, linux-trace-kernel@vger.kernel.org, mark.rutland@arm.com, mathieu.desnoyers@efficios.com, mhiramat@kernel.org, rostedt@goodmis.org, shuah@kernel.org Subject: [PATCH] selftests/ftrace: Fix event filter target_func selection Date: Wed, 20 Mar 2024 14:18:44 +0000 Message-Id: <20240320141844.1779984-1-mark.rutland@arm.com> X-Mailer: git-send-email 2.30.2 Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The event filter function test has been failing in our internal test farm: | # not ok 33 event filter function - test event filtering on functions Running the test in verbose mode indicates that this is because the test erroneously determines that kmem_cache_free() is the most common caller of kmem_cache_free(): # # + cut -d: -f3 trace # # + sed s/call_site=([^+]*)+0x.*/1/ # # + sort # # + uniq -c # # + sort # # + tail -n 1 # # + sed s/^[ 0-9]*// # # + target_func=kmem_cache_free ... and as kmem_cache_free() doesn't call itself, setting this as the filter function for kmem_cache_free() results in no hits, and consequently the test fails: # # + grep kmem_cache_free trace # # + grep kmem_cache_free # # + wc -l # # + hitcnt=0 # # + grep kmem_cache_free trace # # + grep -v kmem_cache_free # # + wc -l # # + misscnt=0 # # + [ 0 -eq 0 ] # # + exit_fail This seems to be because the system in question has tasks with ':' in their name (which a number of kernel worker threads have). These show up in the trace, e.g. test:.sh-1299 [004] ..... 2886.040608: kmem_cache_free: call_site=putname+0xa4/0xc8 ptr=000000000f4d22f4 name=names_cache ... and so when we try to extact the call_site with: cut -d: -f3 trace | sed 's/call_site=\([^+]*\)+0x.*/\1/' ... the 'cut' command will extrace the column containing 'kmem_cache_free' rather than the column containing 'call_site=...', and the 'sed' command will leave this unchanged. Consequently, the test will decide to use 'kmem_cache_free' as the filter function, resulting in the failure seen above. Fix this by matching the 'call_site=' part specifically to extract the function name. Signed-off-by: Mark Rutland Reported-by: Aishwarya TCV Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Shuah Khan Cc: Steven Rostedt Cc: linux-kernel@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: linux-trace-kernel@vger.kernel.org --- .../selftests/ftrace/test.d/filter/event-filter-function.tc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc index 2de7c61d1ae3..3f74c09c56b6 100644 --- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc +++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc @@ -24,7 +24,7 @@ echo 0 > events/enable echo "Get the most frequently calling function" sample_events -target_func=`cut -d: -f3 trace | sed 's/call_site=\([^+]*\)+0x.*/\1/' | sort | uniq -c | sort | tail -n 1 | sed 's/^[ 0-9]*//'` +target_func=`cat trace | grep -o 'call_site=\([^+]*\)' | sed 's/call_site=//' | sort | uniq -c | sort | tail -n 1 | sed 's/^[ 0-9]*//'` if [ -z "$target_func" ]; then exit_fail fi