perf tools: Do backtrace post unwind only if we regs and stack were captured

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@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1347295819-23177-2-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Jiri Olsa 2012-09-10 18:50:16 +02:00 committed by Arnaldo Carvalho de Melo
parent 9ac3e487f0
commit bdde37163e

View File

@ -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);