perf trace: Filter out the trace pid when no threads are specified

To avoid tracing the tracer.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-shmwd1khzpaobr3i0j1ygapg@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 3a696aa70630577b83a33df20a9dddc0206b64f6..cb33e4c8821a8d141de07441f3dfc9a364595a4f 100644 (file)
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -2151,6 +2151,15 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
        if (err < 0)
                goto out_error_open;
 
+       /*
+        * Better not use !target__has_task() here because we need to cover the
+        * case where no threads were specified in the command line, but a
+        * workload was, and in that case we will fill in the thread_map when
+        * we fork the workload in perf_evlist__prepare_workload.
+        */
+       if (evlist->threads->map[0] == -1)
+               perf_evlist__set_filter_pid(evlist, getpid());
+
        err = perf_evlist__mmap(evlist, trace->opts.mmap_pages, false);
        if (err < 0)
                goto out_error_mmap;