tracing: Dump stacktrace trigger to the corresponding instance

The stacktrace event trigger is not 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.

Link: https://lkml.kernel.org/r/afbb0b4f18ba92c276865bc97204d438473f4ebc.1645396236.git.bristot@kernel.org
Cc: stable@vger.kernel.org
Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Tested-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index d00fee7..e0d50c9 100644 (file)
--- 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