From e3d5911221f5cf71e1f0306256d4e42d34a365d2 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Thu, 29 Jan 2015 17:06:44 +0900 Subject: [PATCH] perf record: Show precise number of samples After perf record finishes, it prints file size and number of samples in the file but this info is wrong since it assumes typical sample size of 24 bytes and divides file size by the value. However as we post-process recorded samples for build-id, it can show correct number like below. If build-id post-processing is not requested just omit the wrong number of samples. $ perf record noploop 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.159 MB perf.data (3989 samples) ] $ perf report --stdio -n # To display the perf.data header info, please use --header/--header-only options. # # Samples: 3K of event 'cycles' # Event count (approx.): 3771330663 # # Overhead Samples Command Shared Object Symbol # ........ ............ ....... ................ .......................... # 99.90% 3982 noploop noploop [.] main 0.09% 1 noploop ld-2.17.so [.] _dl_check_map_versions 0.01% 1 noploop [kernel.vmlinux] [k] setup_arg_pages 0.00% 5 noploop [kernel.vmlinux] [k] intel_pmu_enable_all Reported-by: Milian Wolff Signed-off-by: Namhyung Kim Reviewed-by: Jiri Olsa Cc: Adrian Hunter Cc: Andi Kleen Cc: David Ahern Cc: Frederic Weisbecker Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1422518843-25818-4-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-record.c | 51 ++++++++++++++++++++++++++++--------- 1 file changed, 39 insertions(+), 12 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 1134de22979e..9900b433e861 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -190,6 +190,19 @@ static int record__open(struct record *rec) return rc; } +static int process_sample_event(struct perf_tool *tool, + union perf_event *event, + struct perf_sample *sample, + struct perf_evsel *evsel, + struct machine *machine) +{ + struct record *rec = container_of(tool, struct record, tool); + + rec->samples++; + + return build_id__mark_dso_hit(tool, event, sample, evsel, machine); +} + static int process_buildids(struct record *rec) { struct perf_data_file *file = &rec->file; @@ -212,7 +225,7 @@ static int process_buildids(struct record *rec) */ symbol_conf.ignore_vmlinux_buildid = true; - return perf_session__process_events(session, &build_id__mark_dso_hit_ops); + return perf_session__process_events(session, &rec->tool); } static void perf_event__synthesize_guest_os(struct machine *machine, void *data) @@ -503,19 +516,9 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) goto out_child; } - if (!quiet) { + if (!quiet) fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking); - /* - * Approximate RIP event size: 24 bytes. - */ - fprintf(stderr, - "[ perf record: Captured and wrote %.3f MB %s (~%" PRIu64 " samples) ]\n", - (double)rec->bytes_written / 1024.0 / 1024.0, - file->path, - rec->bytes_written / 24); - } - out_child: if (forks) { int exit_status; @@ -534,6 +537,9 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) } else status = err; + /* this will be recalculated during process_buildids() */ + rec->samples = 0; + if (!err && !file->is_pipe) { rec->session->header.data_size += rec->bytes_written; @@ -543,6 +549,20 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) file->fd, true); } + if (!err && !quiet) { + char samples[128]; + + if (rec->samples) + scnprintf(samples, sizeof(samples), + " (%" PRIu64 " samples)", rec->samples); + else + samples[0] = '\0'; + + fprintf(stderr, "[ perf record: Captured and wrote %.3f MB %s%s ]\n", + perf_data_file__size(file) / 1024.0 / 1024.0, + file->path, samples); + } + out_delete_session: perf_session__delete(session); return status; @@ -719,6 +739,13 @@ static struct record record = { .default_per_cpu = true, }, }, + .tool = { + .sample = process_sample_event, + .fork = perf_event__process_fork, + .comm = perf_event__process_comm, + .mmap = perf_event__process_mmap, + .mmap2 = perf_event__process_mmap2, + }, }; #define CALLCHAIN_HELP "setup and enables call-graph (stack chain/backtrace) recording: "