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 ED0851AB6F1; Thu, 14 Nov 2024 21:03:37 +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=1731618218; cv=none; b=M+9dLX7FZPAGAkrRT63fpGWeCoC3nqOJnS7VtuoCWkgdu036EkYxdj98ve6ICmlv8nAgC0pb/ij/t4eqZG60wk0x1PAoCIkrUm6nclsYX/YuckZdfsLJqf/tCTr754XjWC/SCmGhpYtPHGx3vKWbUnWB56NT/m2j3mcfHPbfYEg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731618218; c=relaxed/simple; bh=h6Ab78gAB0LmRRiWpEtwGJHwFKOOZ3XIieV5FxUsQIw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UDyyMOyyB3GPnRPk8iEGEKsak7tsRqVWCHjOjXYGHj05DJNH9Q49QEWom1gLjPZIeDJ4JfSzhj3p/W0aFEUHh/4MsH6/yTLmgih04pEgnPCHHO/xL5eObsSkT5ex+OUa1PH2rkmpfamOBfrMdFoAmDsbMJ5TrpgbOO05v96RFBg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nVLV72CZ; 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="nVLV72CZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79295C4CECD; Thu, 14 Nov 2024 21:03:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731618217; bh=h6Ab78gAB0LmRRiWpEtwGJHwFKOOZ3XIieV5FxUsQIw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nVLV72CZYwZL5SSZBYfmQyD786QqOXvqALMVWo4kAljMWo4bGP9L9mt1qWlnVayYu XFyZmASnhW/XdZOdmomDuDvhjHuenPI6S6byKLiEvA7vAErR/B6fakZec17c7gSMjm 94PZkIwMwmSnOO0QVLMtC1RLzZwgYBfviei9qtlCF9N6EbB/K7nIXRDTNF5sKcT3OV OQKOMzIQ/fU06XHqMVY20O8nR5FANrGe3p7VJigvd0Rl6eXrwF/9yMXrtWyUIHR5U/ SHaUJQLOM4S81PEdHfIIt1/gDIP4jFNPVqlMzCYlxHB/lW6A8uI8Plz2Y4m0E1J3Oe Gmbe36EA7gvew== Date: Thu, 14 Nov 2024 18:03:35 -0300 From: Arnaldo Carvalho de Melo To: Howard Chu Cc: Benjamin Peterson , Peter Zijlstra , Ingo Molnar , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , "Liang, Kan" , open list , "open list:PERFORMANCE EVENTS SUBSYSTEM" Subject: Re: [PATCH 2/2] perf tests: add test for trace output loss Message-ID: References: <20241106234518.115234-1-benjamin@engflow.com> <20241106234518.115234-2-benjamin@engflow.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Thu, Nov 14, 2024 at 12:16:46PM -0800, Howard Chu wrote: > Hello, > > On Thu, Nov 14, 2024 at 12:09 PM Arnaldo Carvalho de Melo > wrote: > > > > On Thu, Nov 14, 2024 at 09:44:56AM -0800, Benjamin Peterson wrote: > > > > On Thu, Nov 14, 2024 at 02:37:52PM -0300, Arnaldo Carvalho de Melo wrote: > > > > diff --git a/tools/perf/tests/shell/trace_exit_race.sh b/tools/perf/tests/shell/trace_exit_race.sh > > > > index 8b70324bc5b4fb4c..c37ed6bb9f7e8fab 100755 > > > > --- a/tools/perf/tests/shell/trace_exit_race.sh > > > > +++ b/tools/perf/tests/shell/trace_exit_race.sh > > > > @@ -12,10 +12,10 @@ > > > > skip_if_no_perf_trace || exit 2 > > > > > > trace_shutdown_race() { > > > > - for i in $(seq 100); do > > > > + for _ in $(seq 100); do > > > > perf trace -e syscalls:sys_enter_exit_group true 2>>$file > > > > done > > > > - [ $(grep -c -E " +[0-9]+\.[0-9]+ +true/[0-9]+ syscalls:sys_enter_exit_group\(\)$" $file) = "100" ] > > > > + [ "$(grep -c -E ' +[0-9]+\.[0-9]+ +true/[0-9]+ syscalls:sys_enter_exit_group\(\)$' $file)" = "100" ] > > > > } > > > > > This all looks okay. > > > > The test is failing for me as there is garbage in the output of perf > > trace even with Namhyung having already applied your previous patch: > > > > ⬢ [acme@toolbox perf-tools-next]$ git log --oneline --author benjamin@engflow.com > > 12bd434f68ea45c7 (HEAD -> perf-tools-next) perf tests: Add test for 'perf trace' output loss > > efbcd2cd7eac10a9 perf trace: Do not lose last events in a race > > 5fb8e56542a3cf46 (perf-tools-next/tmp.perf-tools-next) perf trace: avoid garbage when not printing a trace event's arguments > > ⬢ [acme@toolbox perf-tools-next]$ > > > > root@number:~# perf trace -e syscalls:sys_enter_exit_group true > > 0.000 true/1982428 syscalls:sys_enter_exit_group( k?m) > > root@number:~# perf trace -e syscalls:sys_enter_exit_group true > > 0.000 true/1982430 syscalls:sys_enter_exit_group() > > root@number:~# perf trace -e syscalls:sys_enter_exit_group true > > 0.000 true/1982432 syscalls:sys_enter_exit_group() > > root@number:~# perf trace -e syscalls:sys_enter_exit_group true > > 0.000 true/1982434 syscalls:sys_enter_exit_group() > > root@number:~# perf trace -e syscalls:sys_enter_exit_group true > > 0.000 true/1982437 syscalls:sys_enter_exit_group( k�) > > root@number:~# perf trace -e syscalls:sys_enter_exit_group true > > 0.000 true/1982439 syscalls:sys_enter_exit_group(, loads 8��1) > > root@number:~# > > > > So we don't _miss_ the events, which I was noticing and brought me to > > test your latest 2 patches, which I applied and added a Tested-by, now > > tryint to figure out this garbage... > > Benjamin has already sent v2 to fix this: > https://lore.kernel.org/linux-perf-users/20241107232128.108981-2-benjamin@engflow.com/ Interesting, I wonder why b4 didn't pick the v2 :-\ I'll try it, but see my other message, maybe the way I fixed is simpler? Its a two liner that could be turned into a one liner by right at the start of the function setting bf[0] = '\0', that way we wouldn't need even to check if printed == 0 at the end. Anyway, will test the newer version. - Arnaldo