From d20aff1512f013fab79b8740427b7574569a9a2e Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Tue, 1 Sep 2020 12:37:57 +0300 Subject: perf record: Add 'snapshot' control command Add 'snapshot' control command to create an AUX area tracing snapshot the same as if sending SIGUSR2. The advantage of the FIFO is that access is governed by access to the FIFO. Example: $ mkfifo perf.control $ mkfifo perf.ack $ cat perf.ack & [1] 15235 $ sudo ~/bin/perf record --control fifo:perf.control,perf.ack -S -e intel_pt//u -- sleep 60 & [2] 15243 $ ps -e | grep perf 15244 pts/1 00:00:00 perf $ kill -USR2 15244 bash: kill: (15244) - Operation not permitted $ echo snapshot > perf.control ack $ Signed-off-by: Adrian Hunter Acked-by: Alexey Budankov Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Andi Kleen Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/20200901093758.32293-6-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-record.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) (limited to 'tools/perf/builtin-record.c') diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index c83aec4940de..d0f9f8107f47 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1593,6 +1593,16 @@ static int record__init_clock(struct record *rec) return 0; } +static void hit_auxtrace_snapshot_trigger(struct record *rec) +{ + if (trigger_is_ready(&auxtrace_snapshot_trigger)) { + trigger_hit(&auxtrace_snapshot_trigger); + auxtrace_record__snapshot_started = 1; + if (auxtrace_record__snapshot_start(rec->itr)) + trigger_error(&auxtrace_snapshot_trigger); + } +} + static int __cmd_record(struct record *rec, int argc, const char **argv) { int err; @@ -1937,6 +1947,10 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) case EVLIST_CTL_CMD_DISABLE: pr_info(EVLIST_DISABLED_MSG); break; + case EVLIST_CTL_CMD_SNAPSHOT: + hit_auxtrace_snapshot_trigger(rec); + evlist__ctlfd_ack(rec->evlist); + break; case EVLIST_CTL_CMD_ACK: case EVLIST_CTL_CMD_UNSUPPORTED: default: @@ -2589,7 +2603,8 @@ static struct option __record_options[] = { parse_libpfm_events_option), #endif OPT_CALLBACK(0, "control", &record.opts, "fd:ctl-fd[,ack-fd] or fifo:ctl-fifo[,ack-fifo]", - "Listen on ctl-fd descriptor for command to control measurement ('enable': enable events, 'disable': disable events).\n" + "Listen on ctl-fd descriptor for command to control measurement ('enable': enable events, 'disable': disable events,\n" + "\t\t\t 'snapshot': AUX area tracing snapshot).\n" "\t\t\t Optionally send control command completion ('ack\\n') to ack-fd descriptor.\n" "\t\t\t Alternatively, ctl-fifo / ack-fifo will be opened and used as ctl-fd / ack-fd.", parse_control_option), @@ -2842,12 +2857,7 @@ static void snapshot_sig_handler(int sig __maybe_unused) { struct record *rec = &record; - if (trigger_is_ready(&auxtrace_snapshot_trigger)) { - trigger_hit(&auxtrace_snapshot_trigger); - auxtrace_record__snapshot_started = 1; - if (auxtrace_record__snapshot_start(record.itr)) - trigger_error(&auxtrace_snapshot_trigger); - } + hit_auxtrace_snapshot_trigger(rec); if (switch_output_signal(rec)) trigger_hit(&switch_output_trigger); -- cgit v1.2.3