perf: record TRACE_INFO only if using tracepoints and SAMPLE_RAW

The current perf code implicitly assumes SAMPLE_RAW means tracepoints
are being used, but doesn't check for that.  It happily records the
TRACE_INFO even if SAMPLE_RAW is used without tracepoints, but when the
perf data is read it won't go any further when it finds TRACE_INFO but
no tracepoints, and displays misleading errors.

This adds a check for both in perf-record, and won't record TRACE_INFO
unless both are true.  This at least allows perf report -D to dump raw
events, and avoids triggering a misleading error condition in perf
trace.  It doesn't actually enable the non-tracepoint raw events to be
displayed in perf trace, since perf trace currently only deals with
tracepoint events.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1272865861.7932.16.camel@tropicana>
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-record.c

@@ -560,11 +560,12 @@ static int __cmd_record(int argc, const char **argv)
 			return err;
 	}
 
-	if (raw_samples) {
+	if (raw_samples && have_tracepoints(attrs, nr_counters)) {
 		perf_header__set_feat(&session->header, HEADER_TRACE_INFO);
 	} else {
 		for (i = 0; i < nr_counters; i++) {
-			if (attrs[i].sample_type & PERF_SAMPLE_RAW) {
+			if (attrs[i].sample_type & PERF_SAMPLE_RAW &&
+				attrs[i].type == PERF_TYPE_TRACEPOINT) {
 				perf_header__set_feat(&session->header, HEADER_TRACE_INFO);
 				break;
 			}
@@ -662,19 +663,25 @@ static int __cmd_record(int argc, const char **argv)
 			return err;
 		}
 
-		err = event__synthesize_tracing_data(output, attrs,
+		if (have_tracepoints(attrs, nr_counters)) {
-						     nr_counters,
+			/*
-						     process_synthesized_event,
+			 * FIXME err <= 0 here actually means that
-						     session);
+			 * there were no tracepoints so its not really
-		/*
+			 * an error, just that we don't need to
-		 * FIXME err <= 0 here actually means that there were no tracepoints
+			 * synthesize anything.  We really have to
-		 * so its not really an error, just that we don't need to synthesize
+			 * return this more properly and also
-		 * anything.
+			 * propagate errors that now are calling die()
-		 * We really have to return this more properly and also propagate
+			 */
-		 * errors that now are calling die()
+			err = event__synthesize_tracing_data(output, attrs,
-		 */
+							     nr_counters,
-		if (err > 0)
+							     process_synthesized_event,
+							     session);
+			if (err <= 0) {
+				pr_err("Couldn't record tracing data.\n");
+				return err;
+			}
 			advance_output(err);
+		}
 	}
 
 	machine = perf_session__find_host_machine(session);

tools/perf/util/header.c

@@ -436,7 +436,6 @@ static int perf_header__adds_write(struct perf_header *self, int fd)
 		trace_sec->size = lseek(fd, 0, SEEK_CUR) - trace_sec->offset;
 	}
 
-
 	if (perf_header__has_feat(self, HEADER_BUILD_ID)) {
 		struct perf_file_section *buildid_sec;
 

tools/perf/util/parse-events.h

@@ -13,6 +13,7 @@ struct tracepoint_path {
 };
 
 extern struct tracepoint_path *tracepoint_id_to_path(u64 config);
+extern bool have_tracepoints(struct perf_event_attr *pattrs, int nb_events);
 
 extern int			nr_counters;
 

tools/perf/util/trace-event-info.c

@@ -487,6 +487,11 @@ get_tracepoints_path(struct perf_event_attr *pattrs, int nb_events)
 	return nr_tracepoints > 0 ? path.next : NULL;
 }
 
+bool have_tracepoints(struct perf_event_attr *pattrs, int nb_events)
+{
+	return get_tracepoints_path(pattrs, nb_events) ? true : false;
+}
+
 int read_tracing_data(int fd, struct perf_event_attr *pattrs, int nb_events)
 {
 	char buf[BUFSIZ];