perf tools: Add FIFO file names as alternative options to --control
Enable the --control option to accept file names as an alternative to
file descriptors.
Example:
$ mkfifo perf.control
$ mkfifo perf.ack
$ cat perf.ack &
[1] 6808
$ perf record --control fifo:perf.control,perf.ack -- sleep 300 &
[2] 6810
$ echo disable > perf.control
$ Events disabled
ack
$ echo enable > perf.control
$ Events enabled
ack
$ echo disable > perf.control
$ Events disabled
ack
$ kill %2
[ perf record: Woken up 4 times to write data ]
$ [ perf record: Captured and wrote 0.018 MB perf.data (7 samples) ]
[1]- Done cat perf.ack
[2]+ Terminated perf record --control fifo:perf.control,perf.ack -- sleep 300
$
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200902105707.11491-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 50591e0..c83aec4 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -2236,7 +2236,17 @@ static int parse_control_option(const struct option *opt,
{
struct record_opts *opts = opt->value;
- return evlist__parse_control(str, &opts->ctl_fd, &opts->ctl_fd_ack);
+ return evlist__parse_control(str, &opts->ctl_fd, &opts->ctl_fd_ack, &opts->ctl_fd_close);
+}
+
+static void close_control_option(struct record_opts *opts)
+{
+ if (opts->ctl_fd_close) {
+ opts->ctl_fd_close = false;
+ close(opts->ctl_fd);
+ if (opts->ctl_fd_ack >= 0)
+ close(opts->ctl_fd_ack);
+ }
}
static void switch_output_size_warn(struct record *rec)
@@ -2578,9 +2588,10 @@ static struct option __record_options[] = {
"libpfm4 event selector. use 'perf list' to list available events",
parse_libpfm_events_option),
#endif
- OPT_CALLBACK(0, "control", &record.opts, "fd:ctl-fd[,ack-fd]",
+ 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"
- "\t\t\t Optionally send control command completion ('ack\\n') to ack-fd descriptor.",
+ "\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),
OPT_END()
};
@@ -2653,12 +2664,14 @@ int cmd_record(int argc, const char **argv)
!perf_can_record_switch_events()) {
ui__error("kernel does not support recording context switch events\n");
parse_options_usage(record_usage, record_options, "switch-events", 0);
- return -EINVAL;
+ err = -EINVAL;
+ goto out_opts;
}
if (switch_output_setup(rec)) {
parse_options_usage(record_usage, record_options, "switch-output", 0);
- return -EINVAL;
+ err = -EINVAL;
+ goto out_opts;
}
if (rec->switch_output.time) {
@@ -2669,8 +2682,10 @@ int cmd_record(int argc, const char **argv)
if (rec->switch_output.num_files) {
rec->switch_output.filenames = calloc(sizeof(char *),
rec->switch_output.num_files);
- if (!rec->switch_output.filenames)
- return -EINVAL;
+ if (!rec->switch_output.filenames) {
+ err = -EINVAL;
+ goto out_opts;
+ }
}
/*
@@ -2686,7 +2701,8 @@ int cmd_record(int argc, const char **argv)
rec->affinity_mask.bits = bitmap_alloc(rec->affinity_mask.nbits);
if (!rec->affinity_mask.bits) {
pr_err("Failed to allocate thread mask for %zd cpus\n", rec->affinity_mask.nbits);
- return -ENOMEM;
+ err = -ENOMEM;
+ goto out_opts;
}
pr_debug2("thread mask[%zd]: empty\n", rec->affinity_mask.nbits);
}
@@ -2817,6 +2833,8 @@ int cmd_record(int argc, const char **argv)
evlist__delete(rec->evlist);
symbol__exit();
auxtrace_record__free(rec->itr);
+out_opts:
+ close_control_option(&rec->opts);
return err;
}
