From 49c670b17e555bb9fab4308bb4dd9eadf29872fb Mon Sep 17 00:00:00 2001
From: Ian Rogers <irogers@google.com>
Date: Fri, 26 Aug 2022 09:42:31 -0700
Subject: [PATCH] perf record: Update use of pthread mutex
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Switch to the use of mutex wrappers that provide better error checking
for synth_lock.

Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Truong <alexandre.truong@arm.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: André Almeida <andrealmeid@igalia.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Colin Ian King <colin.king@intel.com>
Cc: Dario Petrillo <dario.pk1@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Dave Marchevsky <davemarchevsky@fb.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Fangrui Song <maskray@google.com>
Cc: Hewenliang <hewenliang4@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jason Wang <wangborong@cdjrlc.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Pavithra Gurushankar <gpavithrasha@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Remi Bernon <rbernon@codeweavers.com>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tom Rix <trix@redhat.com>
Cc: Weiguo Li <liwg06@foxmail.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: William Cohen <wcohen@redhat.com>
Cc: Zechuan Chen <chenzechuan1@huawei.com>
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Cc: yaowenbin <yaowenbin1@huawei.com>
Link: https://lore.kernel.org/r/20220826164242.43412-8-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 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 df83dd4..a91ead7 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"
@@ -616,17 +617,18 @@ 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;
 }
 
@@ -1987,6 +1989,7 @@ static int record__synthesize(struct record *rec, bool tail)
 	}
 
 	if (rec->opts.nr_threads_synthesize > 1) {
+		mutex_init(&synth_lock);
 		perf_set_multithreaded();
 		f = process_locked_synthesized_event;
 	}
@@ -2000,8 +2003,10 @@ 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;
-- 
2.7.4