diff options
| author | Jiri Olsa <jolsa@kernel.org> | 2020-12-27 00:20:38 +0100 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2021-01-20 14:34:21 -0300 |
| commit | 47fddcb479e73c341fb414e40a89572dacadd360 (patch) | |
| tree | 6a968b553d33efc8b1abb4b1814650a23c46f365 /tools/perf/util/evlist.c | |
| parent | f186cd614878dc886edea5df42ca3225d5ab97ea (diff) | |
perf tools: Add 'ping' control command
Add a control 'ping' command to detect if perf is up and its control
interface is operational.
It will be used in following daemon patches to synchronize with record
session - when control interface is up and running, we know that perf
record is monitoring and ready to receive signals.
Example session:
terminal 1:
# mkfifo control ack
# perf record --control=fifo:control,ack
terminal 2:
# echo ping > control
# cat ack
ack
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/20201226232038.390883-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/evlist.c')
| -rw-r--r-- | tools/perf/util/evlist.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index c6de70cefbae..61b2408821e5 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1943,6 +1943,9 @@ static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd, } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_STOP_TAG, (sizeof(EVLIST_CTL_CMD_STOP_TAG)-1))) { *cmd = EVLIST_CTL_CMD_STOP; + } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_PING_TAG, + (sizeof(EVLIST_CTL_CMD_PING_TAG)-1))) { + *cmd = EVLIST_CTL_CMD_PING; } } @@ -2081,6 +2084,7 @@ int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd) break; case EVLIST_CTL_CMD_SNAPSHOT: case EVLIST_CTL_CMD_STOP: + case EVLIST_CTL_CMD_PING: break; case EVLIST_CTL_CMD_ACK: case EVLIST_CTL_CMD_UNSUPPORTED: |