Re: [PATCH] tracing: Dump stacktrace trigger to the corresponding instance

From: Tom Zanussi
Date: Thu Feb 24 2022 - 10:41:43 EST


Hi Daniel,

On Sun, 2022-02-20 at 23:49 +0100, Daniel Bristot de Oliveira wrote:
> The stacktrace event trigger is dumping the stacktrace to the
> instance
> where it was enabled, but to the global "instance."
>
> Use the private_data, pointing to the trigger file, to figure out the
> corresponding trace instance, and use it in the trigger action, like
> snapshot_trigger does.
>
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> Cc: Tom Zanussi <zanussi@xxxxxxxxxx>
> Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
> ---
> kernel/trace/trace_events_trigger.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/trace/trace_events_trigger.c
> b/kernel/trace/trace_events_trigger.c
> index d00fee705f9c..e0d50c9577f3 100644
> --- a/kernel/trace/trace_events_trigger.c
> +++ b/kernel/trace/trace_events_trigger.c
> @@ -1540,7 +1540,12 @@ stacktrace_trigger(struct event_trigger_data
> *data,
> struct trace_buffer *buffer, void *rec,
> struct ring_buffer_event *event)
> {
> - trace_dump_stack(STACK_SKIP);
> + struct trace_event_file *file = data->private_data;
> +
> + if (file)
> + __trace_stack(file->tr, tracing_gen_ctx(), STACK_SKIP);
> + else
> + trace_dump_stack(STACK_SKIP);
> }
>
> static void


Looks good to me.

Reviewed-by: Tom Zanussi <zanussi@xxxxxxxxxx>
Tested-by: Tom Zanussi <zanussi@xxxxxxxxxx>

Thanks,

Tom