[PATCH 53/53] perf record: Allow generate tracking events at the end of output
From: Wang Nan <hidden>
Date: 2016-01-11 13:53:18
Also in:
lkml
Subsystem:
performance events subsystem, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
Before this patch tracking events are generated based on information in /proc before all samples. However, with the introducing of overwrite evsel in perf record, it becomes inconvenience: 'perf record' now can executed as a daemon for sereval hours and only capture the last snapshot when it receives SIGUSR2. The tracking events generated at the head of output 'perf.data' becomes too old, but most of tracking events during 'perf record' running are dropped. This patch generates tracking events at the end of output. The output events series would better reflecting status of system when SIGUSR2 received. Signed-off-by: Wang Nan <redacted> Signed-off-by: He Kuang <redacted> Cc: Arnaldo Carvalho de Melo <redacted> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <redacted> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <redacted> Cc: pi3orama@163.com --- tools/perf/builtin-record.c | 62 +++++++++++++++++++++++++++++++-------------- 1 file changed, 43 insertions(+), 19 deletions(-)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 6ec0529..c1023ce 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c@@ -56,6 +56,7 @@ struct record { bool no_buildid_cache_set; bool timestamp_filename; bool switch_output; + bool tail_tracking; bool tailsize_evt_stopped; unsigned long long samples; };
@@ -639,6 +640,26 @@ record__finish_output(struct record *rec) static int record__synthesize(struct record *rec); +static void record__synthesize_target(struct record *rec) +{ + if (target__none(&rec->opts.target)) { + struct { + struct thread_map map; + struct thread_map_data map_data; + } thread_map; + + thread_map.map.nr = 1; + thread_map.map.map[0].pid = rec->evlist->workload.pid; + thread_map.map.map[0].comm = NULL; + perf_event__synthesize_thread_map(&rec->tool, + &thread_map.map, + process_synthesized_event, + &rec->session->machines.host, + rec->opts.sample_address, + rec->opts.proc_map_timeout); + } +} + static int record__switch_output(struct record *rec, bool at_exit) {
@@ -648,6 +669,11 @@ record__switch_output(struct record *rec, bool at_exit) /* Same Size: "2015122520103046"*/ char timestamp[] = "InvalidTimestamp"; + if (rec->tail_tracking) { + record__synthesize(rec); + record__synthesize_target(rec); + } + rec->samples = 0; record__finish_output(rec); err = fetch_current_timestamp(timestamp, sizeof(timestamp));
@@ -674,23 +700,10 @@ record__switch_output(struct record *rec, bool at_exit) machines__init(&rec->session->machines); perf_session__create_kernel_maps(rec->session); perf_session__set_id_hdr_size(rec->session); - record__synthesize(rec); - if (target__none(&rec->opts.target)) { - struct { - struct thread_map map; - struct thread_map_data map_data; - } thread_map; - - thread_map.map.nr = 1; - thread_map.map.map[0].pid = rec->evlist->workload.pid; - thread_map.map.map[0].comm = NULL; - perf_event__synthesize_thread_map(&rec->tool, - &thread_map.map, - process_synthesized_event, - &rec->session->machines.host, - rec->opts.sample_address, - rec->opts.proc_map_timeout); + if (!rec->tail_tracking) { + record__synthesize(rec); + record__synthesize_target(rec); } } return fd;
@@ -886,9 +899,11 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) machine = &session->machines.host; - err = record__synthesize(rec); - if (err < 0) - goto out_child; + if (!rec->tail_tracking) { + err = record__synthesize(rec); + if (err < 0) + goto out_child; + } if (rec->realtime_prio) { struct sched_param param;
@@ -1021,6 +1036,13 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) disabled = true; } } + + if (rec->tail_tracking) { + err = record__synthesize(rec); + if (err < 0) + goto out_child; + } + auxtrace_snapshot_disable(); if (forks && workload_exec_errno) {
@@ -1446,6 +1468,8 @@ struct option __record_options[] = { "append timestamp to output filename"), OPT_BOOLEAN(0, "switch-output", &record.switch_output, "Switch output when receive SIGUSR2"), + OPT_BOOLEAN(0, "tail-tracking", &record.tail_tracking, + "Generate tracking events at the end of output"), OPT_END() };
--
1.8.3.4