The patch f9db0d0f1b2c ("perf callchain: Allow disabling call graphs
per event") added an ability to enable/disable callchain recording per
event. But it had a problem when the enablement setting is changed at
'perf report' time using -g/--call-graph option.
For example, the following scenario will get a segfault.
$ perf record -ag sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.500 MB perf.data (2555 samples) ]
$ perf report -g none
perf: Segmentation fault
-------- backtrace --------
perf[0x53a98a]
/usr/lib/libc.so.6(+0x335af)[0x7f4e91df95af]
This is because callchain_param.sort() callback was not set but it
tried to call the function as it had the PERF_SAMPLE_CALLCHAIN bit.
Cc: Kan Liang <kan.li...@intel.com>
Signed-off-by: Namhyung Kim <namhy...@kernel.org>
---
tools/perf/util/hist.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index b3567a25f0c4..99b8e14ce010 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -1149,7 +1149,7 @@ void hists__output_resort(struct hists *hists, struct
ui_progress *prog)
struct perf_evsel *evsel = hists_to_evsel(hists);
bool use_callchain;
- if (evsel && !symbol_conf.show_ref_callgraph)
+ if (evsel && symbol_conf.use_callchain &&
!symbol_conf.show_ref_callgraph)
use_callchain = evsel->attr.sample_type & PERF_SAMPLE_CALLCHAIN;
else
use_callchain = symbol_conf.use_callchain;
--
2.5.0
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
