[PATCH v4 07/18] perf record: Update use of pthread mutex

From: Ian Rogers
Date: Fri Aug 26 2022 - 12:45:21 EST


Switch to the use of mutex wrappers that provide better error checking
for synth_lock.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
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..a7b7a317d81b 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);
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;
--
2.37.2.672.g94769d06f0-goog