diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index b3f3b3f1c161..6e8b4649307c 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -596,6 +596,10 @@ Make a copy of /proc/kcore and place it into a directory with the perf data file Limit the sample data max size, is expected to be a number with appended unit character - B/K/M/G +--num-thread-synthesize:: + The number of threads to run when synthesizing events for existing processes. + By default, the number of threads equals 1. + SEE ALSO -------- linkperf:perf-stat[1], linkperf:perf-list[1], linkperf:perf-intel-pt[1] diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 1ab349abe904..2e8011f179f2 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -43,6 +43,7 @@ #include "util/time-utils.h" #include "util/units.h" #include "util/bpf-event.h" +#include "util/util.h" #include "asm/bug.h" #include "perf.h" @@ -50,6 +51,7 @@ #include #include #include +#include #include #include #include @@ -503,6 +505,20 @@ static int process_synthesized_event(struct perf_tool *tool, return record__write(rec, NULL, event, event->header.size); } +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); + ret = process_synthesized_event(tool, event, sample, machine); + pthread_mutex_unlock(&synth_lock); + return ret; +} + static int record__pushfn(struct mmap *map, void *to, void *bf, size_t size) { struct record *rec = to; @@ -1288,6 +1304,7 @@ static int record__synthesize(struct record *rec, bool tail) struct perf_tool *tool = &rec->tool; int fd = perf_data__fd(data); int err = 0; + event_op f = process_synthesized_event; if (rec->opts.tail_synthesize != tail) return 0; @@ -1402,9 +1419,18 @@ static int record__synthesize(struct record *rec, bool tail) if (err < 0) pr_warning("Couldn't synthesize cgroup events.\n"); + if (rec->opts.nr_threads_synthesize > 1) { + perf_set_multithreaded(); + f = process_locked_synthesized_event; + } + err = __machine__synthesize_threads(machine, tool, &opts->target, rec->evlist->core.threads, - process_synthesized_event, opts->sample_address, - 1); + f, opts->sample_address, + rec->opts.nr_threads_synthesize); + + if (rec->opts.nr_threads_synthesize > 1) + perf_set_singlethreaded(); + out: return err; } @@ -2232,6 +2258,7 @@ static struct record record = { .default_per_cpu = true, }, .mmap_flush = MMAP_FLUSH_DEFAULT, + .nr_threads_synthesize = 1, }, .tool = { .sample = process_sample_event, @@ -2421,6 +2448,9 @@ static struct option __record_options[] = { #endif OPT_CALLBACK(0, "max-size", &record.output_max_size, "size", "Limit the maximum size of the output file", parse_output_max_size), + OPT_UINTEGER(0, "num-thread-synthesize", + &record.opts.nr_threads_synthesize, + "number of threads to run for event synthesis"), OPT_END() }; diff --git a/tools/perf/util/record.h b/tools/perf/util/record.h index 24316458be20..923565c3b155 100644 --- a/tools/perf/util/record.h +++ b/tools/perf/util/record.h @@ -68,6 +68,7 @@ struct record_opts { int affinity; int mmap_flush; unsigned int comp_level; + unsigned int nr_threads_synthesize; }; extern const char * const *record_usage;