From mboxrd@z Thu Jan 1 00:00:00 1970 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 1011722E3FD; Fri, 2 May 2025 16:35:58 +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=1746203759; cv=none; b=BWa3rwAvxm03/yzAugNnEVRF2uiJezVyVVsHzowP7irYK84GxODG60VF+EJ6qX6qoDbTdKkw2oWbyb3DOBnA9VdJA2VmH0HZe+M4uLxa6xG4pjjlnshviBH7XwREv62eQoM0q6jN6P88sZrZjglhXb/cw7hwoj2pMUcZrU02Eic= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746203759; c=relaxed/simple; bh=S/qCvrBSGGRtAj9ZsZ/DLBIwlalTY1STD7YmVaAa29g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oG1Cx9gCNCPV7rdtNkfJqQhRAhboYhC0ia6auj3b8byoe2q+N2XzguLXp78oKuWMoX8dxoCZgV88Edx2zfuWxNsL1BwAcFOGAXB0zQuwhb44Y/Ln4ZeSoiMCNMiQL+bmXTBfe4Ooc+LtGxEGFgSK20+C/i64zG07RNy4qrl7Vvk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=U570FMRx; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="U570FMRx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1EC37C4CEE4; Fri, 2 May 2025 16:35:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746203758; bh=S/qCvrBSGGRtAj9ZsZ/DLBIwlalTY1STD7YmVaAa29g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=U570FMRx1Qo0G/QgdqD/GFlUUnMjHerG6l7Bp9281RtY7FV15hPKwZfg6KJB6VqRP 8Q5QIUUWjYgeYeh4sC2lSdUo6yr+HeQ19ABkyxUqcchYQZuLuAudKKQEP0KemBDUgE z+N7dyk7JLcSegQNvHe0Fl8BW1tqLZOv9IYdqT2N01UlPY5p8oq/x+6GBerlouwcGi +xKRsPSw8MYURhRhl99fGGo5mWT2Rw2J8g7A2WJWXdSGIYNn97pF45cX6fpF3dghig zlxmhcnhCm2OM2CYp/FxlutBk1YvZkhicQAPAhZQNyfYmBhw59UNnNhdHJzAzGWEIt tr0JBiUiRLEuQ== Date: Fri, 2 May 2025 13:35:55 -0300 From: Arnaldo Carvalho de Melo To: Thomas Richter Cc: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-perf-users@vger.kernel.org, namhyung@kernel.org, agordeev@linux.ibm.com, gor@linux.ibm.com, sumanthk@linux.ibm.com, hca@linux.ibm.com, irogers@google.com, ctshao@google.com Subject: Re: [PATCH V4] perf test: Allow tolerance for leader sampling test Message-ID: References: <20250430140611.599078-1-tmricht@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250430140611.599078-1-tmricht@linux.ibm.com> On Wed, Apr 30, 2025 at 04:06:11PM +0200, Thomas Richter wrote: > V4: Update to be applied onto linux-next > V3: Added check for missing samples as suggested by Chun-Tse. > V2: Changed bc invocation to return 0 on success and 1 on error. > > There is a known issue that the leader sampling is inconsistent, since > throttle only affect leader, not the slave. The detail is in [1]. To > maintain test coverage, this patch sets a tolerance rate of 80% to > accommodate the throttled samples and prevent test failures due to > throttling. > > [1] lore.kernel.org/20250328182752.769662-1-ctshao@google.com > > Signed-off-by: Chun-Tse Shao > Suggested-by: Ian Rogers > Suggested-by: Thomas Richter But who is the author? As-is this patch states Thomas Richter as the author, but since there is also a Suggested-by and Tested-by Thomas Richter, it makes me believe the author is Chun-Tse Shao, is that the case? - Arnaldo > Tested-by: Thomas Richter > Signed-off-by: Thomas Richter > --- > tools/perf/tests/shell/record.sh | 33 ++++++++++++++++++++++++++------ > 1 file changed, 27 insertions(+), 6 deletions(-) > > diff --git a/tools/perf/tests/shell/record.sh b/tools/perf/tests/shell/record.sh > index 05d91a663fda..587f62e34414 100755 > --- a/tools/perf/tests/shell/record.sh > +++ b/tools/perf/tests/shell/record.sh > @@ -240,22 +240,43 @@ test_leader_sampling() { > err=1 > return > fi > + perf script -i "${perfdata}" | grep brstack > $script_output > + # Check if the two instruction counts are equal in each record. > + # However, the throttling code doesn't consider event grouping. During throttling, only the > + # leader is stopped, causing the slave's counts significantly higher. To temporarily solve this, > + # let's set the tolerance rate to 80%. > + # TODO: Revert the code for tolerance once the throttling mechanism is fixed. > index=0 > - perf script -i "${perfdata}" > "${script_output}" > + valid_counts=0 > + invalid_counts=0 > + tolerance_rate=0.8 > while IFS= read -r line > do > - # Check if the two instruction counts are equal in each record > cycles=$(echo $line | awk '{for(i=1;i<=NF;i++) if($i=="cycles:") print $(i-1)}') > if [ $(($index%2)) -ne 0 ] && [ ${cycles}x != ${prev_cycles}x ] > then > - echo "Leader sampling [Failed inconsistent cycles count]" > - err=1 > - return > + invalid_counts=$(($invalid_counts+1)) > + else > + valid_counts=$(($valid_counts+1)) > fi > index=$(($index+1)) > prev_cycles=$cycles > done < "${script_output}" > - echo "Basic leader sampling test [Success]" > + total_counts=$(bc <<< "$invalid_counts+$valid_counts") > + if (( $(bc <<< "$total_counts <= 0") )) > + then > + echo "Leader sampling [No sample generated]" > + err=1 > + return > + fi > + isok=$(bc <<< "scale=2; if (($invalid_counts/$total_counts) < (1-$tolerance_rate)) { 0 } else { 1 };") > + if [ $isok -eq 1 ] > + then > + echo "Leader sampling [Failed inconsistent cycles count]" > + err=1 > + else > + echo "Basic leader sampling test [Success]" > + fi > } > > test_topdown_leader_sampling() { > -- > 2.45.2