| From | Wang Nan <> | Subject | [PATCH 02/31] perf tools: Don't set cmdline_group_boundary if no evsel is collected | Date | Sat, 29 Aug 2015 04:21:36 +0000 |
| |
If parse_events__scanner() collects no entry, perf_evlist__last(evlist) is invalid. Then setting of cmdline_group_boundary touches invalid.
It could happend in currect BPF implementation. See [1]. Although it can be fixed, for safety reason it whould be better to introduce this check.
Instead of checking number of entries, check data.list instead, so we can add dummy evsel here.
[1]: http://lkml.kernel.org/n/1436445342-1402-19-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Link: http://lkml.kernel.org/r/1440742821-44548-3-git-send-email-wangnan0@huawei.com --- tools/perf/util/parse-events.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index d826e6f..14cd7e3 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -1143,10 +1143,14 @@ int parse_events(struct perf_evlist *evlist, const char *str, int entries = data.idx - evlist->nr_entries; struct perf_evsel *last; + if (!list_empty(&data.list)) { + last = list_entry(data.list.prev, + struct perf_evsel, node); + last->cmdline_group_boundary = true; + } + perf_evlist__splice_list_tail(evlist, &data.list, entries); evlist->nr_groups += data.nr_groups; - last = perf_evlist__last(evlist); - last->cmdline_group_boundary = true; return 0; } -- 2.1.0
|