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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5545FC00140 for ; Wed, 24 Aug 2022 10:15:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235404AbiHXKPP (ORCPT ); Wed, 24 Aug 2022 06:15:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60556 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231846AbiHXKPO (ORCPT ); Wed, 24 Aug 2022 06:15:14 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16BAC4454C; Wed, 24 Aug 2022 03:15:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1661336114; x=1692872114; h=message-id:date:mime-version:subject:to:references:from: in-reply-to:content-transfer-encoding; bh=F3hdBdWFw9/N+cVdceQJWxxc8Y/utx6ligUGZLp/CII=; b=cQMpBQKt7Yyk96JQ6wAy8DzybVEdQTYXA0B6IyXAvlpq4E1bK/1i7Xoc CJNT2xRLLCDiqCqh4/CHjPy8zwQFE0RObaZ+BJ9rSnKYwcIk/OGm7tWh9 bUj3rqvnNoEmTbxMTqi+fVgzmVs8biJg/PlX700eXjgHKM3xTQ8uJRP3h ZJP77B5sr93tp1CL7GbobaGmJ8/ftHrG5BzrOGlyTsgk5XiN5fMGZ69bh OECJR6CwMrE5aKgoPMpnCSmd8oIna3B3vZjPBjQqLUm5qoLbTKtPN6vd/ rcno1WJXj0nJE3laUuSZtrVgEuOjvHxt7ClOZ3RLbxbHl+4IvLTsvlB1J w==; X-IronPort-AV: E=McAfee;i="6500,9779,10448"; a="380218898" X-IronPort-AV: E=Sophos;i="5.93,260,1654585200"; d="scan'208";a="380218898" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Aug 2022 03:15:13 -0700 X-IronPort-AV: E=Sophos;i="5.93,260,1654585200"; d="scan'208";a="586375894" Received: from ahunter6-mobl1.ger.corp.intel.com (HELO [10.0.2.15]) ([10.252.51.108]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Aug 2022 03:15:00 -0700 Message-ID: <02152f40-1dc5-7f1b-ad88-61ecb146a3da@intel.com> Date: Wed, 24 Aug 2022 13:14:55 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0 Thunderbird/91.11.0 Subject: Re: [PATCH v2 07/18] perf record: Update use of pthread mutex Content-Language: en-US To: Ian Rogers , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Darren Hart , Davidlohr Bueso , =?UTF-8?Q?Andr=c3=a9_Almeida?= , Nathan Chancellor , Nick Desaulniers , Tom Rix , Weiguo Li , Athira Rajeev , Thomas Richter , Ravi Bangoria , Dario Petrillo , Hewenliang , yaowenbin , Wenyu Liu , Song Liu , Andrii Nakryiko , Dave Marchevsky , Leo Yan , Kim Phillips , Pavithra Gurushankar , Alexandre Truong , Quentin Monnet , William Cohen , Andres Freund , Adrian Hunter , =?UTF-8?Q?Martin_Li=c5=a1ka?= , Colin Ian King , James Clark , Fangrui Song , Stephane Eranian , Kajol Jain , Alexey Bayduraev , Riccardo Mancini , Andi Kleen , Masami Hiramatsu , Zechuan Chen , Jason Wang , Christophe JAILLET , Remi Bernon , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, bpf@vger.kernel.org, llvm@lists.linux.dev References: <20220823220922.256001-1-irogers@google.com> <20220823220922.256001-8-irogers@google.com> From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki In-Reply-To: <20220823220922.256001-8-irogers@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org On 24/08/22 01:09, Ian Rogers wrote: > Switch to the use of mutex wrappers that provide better error checking > for synth_lock. It would be better to distinguish patches that make drop-in replacements from patches like this that change logic. > > Signed-off-by: Ian Rogers > --- > tools/perf/builtin-record.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c > index 4713f0f3a6cf..02eb85677e99 100644 > --- a/tools/perf/builtin-record.c > +++ b/tools/perf/builtin-record.c > @@ -21,6 +21,7 @@ > #include "util/evsel.h" > #include "util/debug.h" > #include "util/mmap.h" > +#include "util/mutex.h" > #include "util/target.h" > #include "util/session.h" > #include "util/tool.h" > @@ -608,17 +609,18 @@ static int process_synthesized_event(struct perf_tool *tool, > return record__write(rec, NULL, event, event->header.size); > } > > +static struct mutex synth_lock; > + > static int process_locked_synthesized_event(struct perf_tool *tool, > union perf_event *event, > struct perf_sample *sample __maybe_unused, > struct machine *machine __maybe_unused) > { > - static pthread_mutex_t synth_lock = PTHREAD_MUTEX_INITIALIZER; > int ret; > > - pthread_mutex_lock(&synth_lock); > + mutex_lock(&synth_lock); > ret = process_synthesized_event(tool, event, sample, machine); > - pthread_mutex_unlock(&synth_lock); > + mutex_unlock(&synth_lock); > return ret; > } > > @@ -1917,6 +1919,7 @@ static int record__synthesize(struct record *rec, bool tail) > } > > if (rec->opts.nr_threads_synthesize > 1) { > + mutex_init(&synth_lock, /*pshared=*/false); It would be better to have mutex_init() and mutex_init_shared() since /*pshared=*/true is rarely used. > perf_set_multithreaded(); > f = process_locked_synthesized_event; > } > @@ -1930,8 +1933,10 @@ static int record__synthesize(struct record *rec, bool tail) > rec->opts.nr_threads_synthesize); > } > > - if (rec->opts.nr_threads_synthesize > 1) > + if (rec->opts.nr_threads_synthesize > 1) { > perf_set_singlethreaded(); > + mutex_destroy(&synth_lock); > + } > > out: > return err;