[PATCH 09/18] perf tools: Do backtrace post unwind only if we regs and stack were captured
From: Arnaldo Carvalho de Melo
Date: Tue Sep 11 2012 - 19:53:57 EST
From: Jiri Olsa <jolsa@xxxxxxxxxx>
Bail out without error if we want to do backtrace post unwind, but were
not able to capture user registers or user stack during the record
phase, which is possible and valid case.
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1347295819-23177-2-git-send-email-jolsa@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/session.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 3806ea4..0ecd62b 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -388,6 +388,11 @@ int machine__resolve_callchain(struct machine *machine,
(evsel->attr.sample_type & PERF_SAMPLE_STACK_USER)))
return 0;
+ /* Bail out if nothing was captured. */
+ if ((!sample->user_regs.regs) ||
+ (!sample->user_stack.size))
+ return 0;
+
return unwind__get_entries(unwind_entry, &callchain_cursor, machine,
thread, evsel->attr.sample_regs_user,
sample);
--
1.7.9.2.358.g22243
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/