perf tools: Fix crash on synthesizing the unit

[ Upstream commit fb50c09e923870a358d68b0d58891bd145b8d7c7 ]

Adam reported a record command crash for simple session like:

  $ perf record -e cpu-clock ls

with following backtrace:

  Program received signal SIGSEGV, Segmentation fault.
  3543            ev = event_update_event__new(size + 1, PERF_EVENT_UPDATE__UNIT, evsel->id[0]);
  (gdb) bt
  #0  perf_event__synthesize_event_update_unit
  #1  0x000000000051e469 in perf_event__synthesize_extra_attr
  #2  0x00000000004445cb in record__synthesize
  #3  0x0000000000444bc5 in __cmd_record
  ...

We synthesize an update event that needs to touch the evsel id array,
which is not defined at that time. Fix this by forcing the id allocation
for events with their unit defined.

Reflecting possible read_format ID bit in the attr tests.

Reported-by: Yongxin Liu <yongxin.liu@outlook.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adam Lee <leeadamrobert@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201477
Fixes: bfd8f72c2778 ("perf record: Synthesize unit/scale/... in event update")
Link: http://lkml.kernel.org/r/20181112130012.5424-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/tools/perf/tests/attr/base-record b/tools/perf/tests/attr/base-record
index 37940665f736c7850a61fcaa107a4bdd228a7668..efd0157b9d223f14cd305c09159c5955744b3762 100644 (file)
--- a/tools/perf/tests/attr/base-record
+++ b/tools/perf/tests/attr/base-record
@@ -9,7 +9,7 @@ size=112
 config=0
 sample_period=*
 sample_type=263
-read_format=0
+read_format=0|4
 disabled=1
 inherit=1
 pinned=0

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 03a72310315fa4593db75370a74576f7813d97a6..e7dbdcc8d46532a320dedc5019034bbe3bda7868 100644 (file)
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1088,7 +1088,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts,
                attr->exclude_user   = 1;
        }
 
-       if (evsel->own_cpus)
+       if (evsel->own_cpus || evsel->unit)
                evsel->attr.read_format |= PERF_FORMAT_ID;
 
        /*