| From: Steven Rostedt <rostedt@goodmis.org> |
| Date: Wed, 16 May 2018 09:36:44 -0400 |
| Subject: [PATCH 2/5] tracing: Add field parsing hist error for hist triggers |
| |
| From: Tom Zanussi <tom.zanussi@linux.intel.com> |
| |
| [ commit 5ec432d7bf9dd3b4a2b84f8974e3adb71f45fb1d ] |
| |
| If the user specifies a nonexistent field for a hist trigger, the |
| current code correctly flags that as an error, but doesn't tell the |
| user what happened. |
| |
| Fix this by invoking hist_err() with an appropriate message when |
| nonexistent fields are specified. |
| |
| Before: |
| |
| # echo 'hist:keys=pid:ts0=common_timestamp.usecs' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger |
| -su: echo: write error: Invalid argument |
| # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist |
| |
| After: |
| |
| # echo 'hist:keys=pid:ts0=common_timestamp.usecs' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger |
| -su: echo: write error: Invalid argument |
| # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist |
| ERROR: Couldn't find field: pid |
| Last command: keys=pid:ts0=common_timestamp.usecs |
| |
| Link: http://lkml.kernel.org/r/fdc8746969d16906120f162b99dd71c741e0b62c.1524790601.git.tom.zanussi@linux.intel.com |
| |
| Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> |
| Reported-by: Masami Hiramatsu <mhiramat@kernel.org> |
| Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> |
| Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| --- |
| kernel/trace/trace_events_hist.c | 1 + |
| 1 file changed, 1 insertion(+) |
| |
| --- a/kernel/trace/trace_events_hist.c |
| +++ b/kernel/trace/trace_events_hist.c |
| @@ -2482,6 +2482,7 @@ parse_field(struct hist_trigger_data *hi |
| else { |
| field = trace_find_event_field(file->event_call, field_name); |
| if (!field || !field->size) { |
| + hist_err("Couldn't find field: ", field_name); |
| field = ERR_PTR(-EINVAL); |
| goto out; |
| } |
