Commit f186cd61 authored Dec 27, 2020 by Jiri Olsa Committed by Arnaldo Carvalho de Melo Jan 20, 2021

perf tools: Add 'stop' control command



Adding control 'stop' command to stop perf record.

When it is received, perf will set the 'done' variable to 1 to stop its
mmap ring buffer reading loop.

Example session:

  terminal 1:
    # mkfifo control ack
    # perf record --control=fifo:control,ack

  terminal 2:
    # echo stop > control

  terminal 1:
    [ perf record: Woken up 7 times to write data ]
    [ perf record: Captured and wrote 3.214 MB perf.data (38280 samples) ]
    #

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Budankov <abudankov@huawei.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201226232038.390883-4-jolsa@kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 142544a9

tools/perf/Documentation/perf-record.txt

+1 −0

Original line number	Diff line number	Diff line
		@@ -651,6 +651,7 @@ Available commands:
		'enable name' : enable event 'name'
		'disable name' : disable event 'name'
		'snapshot' : AUX area tracing snapshot).
		'stop' : stop perf record

		'evlist [-v\|-g\|-F] : display all events
		-F Show just the sample frequency used for each event.

tools/perf/builtin-record.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -1942,6 +1942,9 @@ static int __cmd_record(struct record rec, int argc, const char *argv)
		hit_auxtrace_snapshot_trigger(rec);
		evlist__ctlfd_ack(rec->evlist);
		break;
		case EVLIST_CTL_CMD_STOP:
		done = 1;
		break;
		case EVLIST_CTL_CMD_ACK:
		case EVLIST_CTL_CMD_UNSUPPORTED:
		case EVLIST_CTL_CMD_ENABLE:

tools/perf/builtin-stat.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -622,6 +622,7 @@ static void process_evlist(struct evlist *evlist, unsigned int interval)
		case EVLIST_CTL_CMD_ACK:
		case EVLIST_CTL_CMD_UNSUPPORTED:
		case EVLIST_CTL_CMD_EVLIST:
		case EVLIST_CTL_CMD_STOP:
		default:
		break;
		}

tools/perf/util/evlist.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -1940,6 +1940,9 @@ static int evlist__ctlfd_recv(struct evlist evlist, enum evlist_ctl_cmd cmd,
		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_EVLIST_TAG,
		(sizeof(EVLIST_CTL_CMD_EVLIST_TAG)-1))) {
		*cmd = EVLIST_CTL_CMD_EVLIST;
		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_STOP_TAG,
		(sizeof(EVLIST_CTL_CMD_STOP_TAG)-1))) {
		*cmd = EVLIST_CTL_CMD_STOP;
		}
		}

		@@ -2077,6 +2080,7 @@ int evlist__ctlfd_process(struct evlist evlist, enum evlist_ctl_cmd cmd)
		err = evlist__ctlfd_list(evlist, cmd_data);
		break;
		case EVLIST_CTL_CMD_SNAPSHOT:
		case EVLIST_CTL_CMD_STOP:
		break;
		case EVLIST_CTL_CMD_ACK:
		case EVLIST_CTL_CMD_UNSUPPORTED:

tools/perf/util/evlist.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -331,6 +331,7 @@ struct evsel evlist__reset_weak_group(struct evlist evlist, struct evsel *evse
		#define EVLIST_CTL_CMD_ACK_TAG "ack\n"
		#define EVLIST_CTL_CMD_SNAPSHOT_TAG "snapshot"
		#define EVLIST_CTL_CMD_EVLIST_TAG "evlist"
		#define EVLIST_CTL_CMD_STOP_TAG "stop"

		#define EVLIST_CTL_CMD_MAX_LEN 64

		@@ -341,6 +342,7 @@ enum evlist_ctl_cmd {
		EVLIST_CTL_CMD_ACK,
		EVLIST_CTL_CMD_SNAPSHOT,
		EVLIST_CTL_CMD_EVLIST,
		EVLIST_CTL_CMD_STOP,
		};

		int evlist__parse_control(const char str, int ctl_fd, int ctl_fd_ack, bool ctl_fd_close);