On Fri, 19 Nov 2021 12:24:20 +0100
Vincent Whitchurch <vincent.whitchurch@xxxxxxxx> wrote:
> Do not segfault if the event cannot be found for some reason and
> tep_find_event_by_record() returns NULL.
>
> No extra warning is added since there are others ("UNKNOWN EVENT") which
> already make it clear that something is wrong:
>
> kworker/u8:0-7 [003] 1.245773: sched_stat_runtime: comm=kworker/u8:...
> [UNKNOWN EVENT][UNKNOWN EVENT][UNKNOWN EVENT]
> kworker/u8:0-7 [003] 1.245776: sched_switch: kworker/u8:0:7 [120] W...
>
I wonder if the following would be a better and more robust approach:
diff --git a/tracecmd/trace-read.c b/tracecmd/trace-read.c
index f7ffb89e..4b27740a 100644
--- a/tracecmd/trace-read.c
+++ b/tracecmd/trace-read.c
@@ -142,12 +142,15 @@ static struct trace_hash wakeup_hash;
static void print_event_name(struct trace_seq *s, struct tep_event *event)
{
static const char *spaces = " "; /* 20 spaces */
+ const char *name;
int len;
- trace_seq_printf(s, " %s: ", event->name);
+ name = event ? event->name : "(NULL)";
+
+ trace_seq_printf(s, " %s: ", name);
/* Space out the event names evenly. */
- len = strlen(event->name);
+ len = strlen(name);
if (len < 20)
trace_seq_printf(s, "%.*s", 20 - len, spaces);
}
-- Steve
|