perf record: Fix the profiling of existing pid or whole box
Perf record bails if no command argument is provided, so you can't use
naked -a or -p to profile a running task or the whole box.
Allow foreground profiling of an existing pid or the entire system.
[ Impact: fix command option handling bug ]
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/Documentation/perf_counter/builtin-record.c b/Documentation/perf_counter/builtin-record.c
index 431077a..4a06866 100644
--- a/Documentation/perf_counter/builtin-record.c
+++ b/Documentation/perf_counter/builtin-record.c
@@ -354,7 +354,7 @@
signal(SIGCHLD, sig_handler);
signal(SIGINT, sig_handler);
- if (target_pid == -1) {
+ if (target_pid == -1 && argc) {
pid = fork();
if (pid < 0)
perror("failed to fork");
@@ -430,7 +430,7 @@
create_events_help(events_help_msg);
argc = parse_options(argc, argv, options, record_usage, 0);
- if (!argc)
+ if (!argc && target_pid == -1 && !system_wide)
usage_with_options(record_usage, options);
if (!nr_counters) {