From 1d078ccb33807546c73e07a79fca6a976b7ecac8 Mon Sep 17 00:00:00 2001 From: Alexey Budankov Date: Fri, 17 Jul 2020 10:08:23 +0300 Subject: perf record: Introduce --control fd:ctl-fd[,ack-fd] options Introduce --control fd:ctl-fd[,ack-fd] options to pass open file descriptors numbers from command line. Extend perf-record.txt file with --control fd:ctl-fd[,ack-fd] options description. Document possible usage model introduced by --control fd:ctl-fd[,ack-fd] options by providing example bash shell script. Signed-off-by: Alexey Budankov Acked-by: Jiri Olsa Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Andi Kleen Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/8dc01e1a-3a80-3f67-5385-4bc7112b0dd3@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-record.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'tools/perf/builtin-record.c') diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 739601ecdaff..42978ff65b3b 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1786,6 +1786,9 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) perf_evlist__start_workload(rec->evlist); } + if (evlist__initialize_ctlfd(rec->evlist, opts->ctl_fd, opts->ctl_fd_ack)) + goto out_child; + if (opts->initial_delay) { pr_info(EVLIST_DISABLED_MSG); if (opts->initial_delay > 0) { @@ -1932,6 +1935,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) record__synthesize_workload(rec, true); out_child: + evlist__finalize_ctlfd(rec->evlist); record__mmap_read_all(rec, true); record__aio_mmap_read_sync(rec); @@ -2281,6 +2285,33 @@ out_free: return ret; } +static int parse_control_option(const struct option *opt, + const char *str, + int unset __maybe_unused) +{ + char *comma = NULL, *endptr = NULL; + struct record_opts *config = (struct record_opts *)opt->value; + + if (strncmp(str, "fd:", 3)) + return -EINVAL; + + config->ctl_fd = strtoul(&str[3], &endptr, 0); + if (endptr == &str[3]) + return -EINVAL; + + comma = strchr(str, ','); + if (comma) { + if (endptr != comma) + return -EINVAL; + + config->ctl_fd_ack = strtoul(comma + 1, &endptr, 0); + if (endptr == comma + 1 || *endptr != '\0') + return -EINVAL; + } + + return 0; +} + static void switch_output_size_warn(struct record *rec) { u64 wakeup_size = evlist__mmap_size(rec->opts.mmap_pages); @@ -2417,6 +2448,8 @@ static struct record record = { }, .mmap_flush = MMAP_FLUSH_DEFAULT, .nr_threads_synthesize = 1, + .ctl_fd = -1, + .ctl_fd_ack = -1, }, .tool = { .sample = process_sample_event, @@ -2618,6 +2651,10 @@ 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]", + "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.", + parse_control_option), OPT_END() }; -- cgit v1.2.3