[PATCH 1/3] perf: record TRACE_INFO only if using tracepoints and SAMPLE_RAW

From: Arnaldo Carvalho de Melo
Date: Tue May 04 2010 - 10:00:30 EST


From: Tom Zanussi <tzanussi@xxxxxxxxx>

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: FrÃdÃric Weisbecker <fweisbec@xxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
LKML-Reference: <1272865861.7932.16.camel@tropicana>
Signed-off-by: Tom Zanussi <tzanussi@xxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-record.c | 35 +++++++++++++++++++++--------------
tools/perf/util/header.c | 1 -
tools/perf/util/parse-events.h | 1 +
tools/perf/util/trace-event-info.c | 5 +++++
4 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index ac989e9..0ff67d1 100644
--- a/tools/perf/builtin-record.c
+++ b/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,
- nr_counters,
- process_synthesized_event,
- session);
- /*
- * FIXME err <= 0 here actually means that there were no tracepoints
- * so its not really an error, just that we don't need to synthesize
- * anything.
- * We really have to return this more properly and also propagate
- * errors that now are calling die()
- */
- if (err > 0)
+ if (have_tracepoints(attrs, nr_counters)) {
+ /*
+ * FIXME err <= 0 here actually means that
+ * there were no tracepoints so its not really
+ * an error, just that we don't need to
+ * synthesize anything. 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,
+ 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);
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 79da0e5..2b9f898 100644
--- a/tools/perf/util/header.c
+++ b/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;

diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index b8c1f64..fc4ab3f 100644
--- a/tools/perf/util/parse-events.h
+++ b/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;

diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index 30cd9b5..0a1fb9d 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/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];
--
1.6.2.5

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