perf evsel: Add 'no_aux_samples' option

Add an option to prevent additional samples being added to a selected
event by perf_evsel__config().

This is needed when using the sched_switch tracepoint to follow object
code execution.  Since sched_switch will be used only for switch
information, additional sampling is wasteful.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1405332185-4050-33-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/evsel.c

@@ -623,7 +623,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
 		attr->mmap_data = track;
 	}
 
-	if (opts->call_graph_enabled)
+	if (opts->call_graph_enabled && !evsel->no_aux_samples)
 		perf_evsel__config_callgraph(evsel, opts);
 
 	if (target__has_cpu(&opts->target))
@@ -637,7 +637,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
 	     target__has_cpu(&opts->target) || per_cpu))
 		perf_evsel__set_sample_bit(evsel, TIME);
 
-	if (opts->raw_samples) {
+	if (opts->raw_samples && !evsel->no_aux_samples) {
 		perf_evsel__set_sample_bit(evsel, TIME);
 		perf_evsel__set_sample_bit(evsel, RAW);
 		perf_evsel__set_sample_bit(evsel, CPU);
@@ -650,7 +650,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
 		attr->watermark = 0;
 		attr->wakeup_events = 1;
 	}
-	if (opts->branch_stack) {
+	if (opts->branch_stack && !evsel->no_aux_samples) {
 		perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
 		attr->branch_sample_type = opts->branch_stack;
 	}

tools/perf/util/evsel.h

@@ -83,6 +83,7 @@ struct perf_evsel {
 	int			is_pos;
 	bool 			supported;
 	bool 			needs_swap;
+	bool			no_aux_samples;
 	/* parse modifier helper */
 	int			exclude_GH;
 	int			nr_members;