[PATCH 5.16 113/164] tracing: Have traceon and traceoff trigger honor the instance

Greg Kroah-Hartman
2022-02-28T18:10:04Z

From: Steven Rostedt (Google) <rostedt@goodmis.org>

commit 302e9edd54985f584cfc180098f3554774126969 upstream.

If a trigger is set on an event to disable or enable tracing within an
instance, then tracing should be disabled or enabled in the instance and
not at the top level, which is confusing to users.

Link: https://lkml.kernel.org/r/20220223223837.14f94ec3@rorschach.local.home

Cc: stable@vger.kernel.org
Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables")
Tested-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/trace/trace_events_trigger.c | 52 +++++++++++++++++++++++++++++++-----
1 file changed, 46 insertions(+), 6 deletions(-)

--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -955,6 +955,16 @@ traceon_trigger(struct event_trigger_dat
struct trace_buffer *buffer, void *rec,
struct ring_buffer_event *event)
{
+ struct trace_event_file *file = data->private_data;
+
+ if (file) {
+ if (tracer_tracing_is_on(file->tr))
+ return;
+
+ tracer_tracing_on(file->tr);
+ return;
+ }
+
if (tracing_is_on())
return;

@@ -966,8 +976,15 @@ traceon_count_trigger(struct event_trigg
struct trace_buffer *buffer, void *rec,
struct ring_buffer_event *event)
{
- if (tracing_is_on())
- return;
+ struct trace_event_file *file = data->private_data;
+
+ if (file) {
+ if (tracer_tracing_is_on(file->tr))
+ return;
+ } else {
+ if (tracing_is_on())
+ return;
+ }

if (!data->count)
return;
@@ -975,7 +992,10 @@ traceon_count_trigger(struct event_trigg
if (data->count != -1)
(data->count)--;

- tracing_on();
+ if (file)
+ tracer_tracing_on(file->tr);
+ else
+ tracing_on();
}

static void
@@ -983,6 +1003,16 @@ traceoff_trigger(struct event_trigger_da
struct trace_buffer *buffer, void *rec,
struct ring_buffer_event *event)
{
+ struct trace_event_file *file = data->private_data;
+
+ if (file) {
+ if (!tracer_tracing_is_on(file->tr))
+ return;
+
+ tracer_tracing_off(file->tr);
+ return;
+ }
+
if (!tracing_is_on())
return;

@@ -994,8 +1024,15 @@ traceoff_count_trigger(struct event_trig
struct trace_buffer *buffer, void *rec,
struct ring_buffer_event *event)
{
- if (!tracing_is_on())
- return;
+ struct trace_event_file *file = data->private_data;
+
+ if (file) {
+ if (!tracer_tracing_is_on(file->tr))
+ return;
+ } else {
+ if (!tracing_is_on())
+ return;
+ }

if (!data->count)
return;
@@ -1003,7 +1040,10 @@ traceoff_count_trigger(struct event_trig
if (data->count != -1)
(data->count)--;

- tracing_off();
+ if (file)
+ tracer_tracing_off(file->tr);
+ else
+ tracing_off();
}

static int