From dd1a50377c92321f78fa4d0601bb4d88d88670ab Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 20 Jul 2017 11:17:51 -0300 Subject: perf trace: Introduce filter_loop_pids() No change in functionality, just to make clearer that what we want when filtering the tracer pid in a system wide tracing session is to avoid a feedback loop. This also paves the way for a more interesting loop avoidance algorithm, one that tries to figure out if we are in a ssh session, xterm, etc. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-5fcttc5kdjkcyp9404ezkuy9@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'tools/perf/builtin-trace.c') diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 9e74e675d7cb..0ba36f08efd8 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2239,6 +2239,16 @@ out_enomem: goto out; } +static int trace__set_filter_loop_pids(struct trace *trace) +{ + int nr = 1; + pid_t pids[32] = { + getpid(), + }; + + return perf_evlist__set_filter_pids(trace->evlist, nr, pids); +} + static int trace__run(struct trace *trace, int argc, const char **argv) { struct perf_evlist *evlist = trace->evlist; @@ -2362,7 +2372,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv) if (trace->filter_pids.nr > 0) err = perf_evlist__set_filter_pids(evlist, trace->filter_pids.nr, trace->filter_pids.entries); else if (thread_map__pid(evlist->threads, 0) == -1) - err = perf_evlist__set_filter_pid(evlist, getpid()); + err = trace__set_filter_loop_pids(trace); if (err < 0) goto out_error_mem; -- cgit v1.2.3