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Date:   Wed, 23 Feb 2022 22:38:37 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     LKML <linux-kernel@vger.kernel.org>
Cc:     Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Tom Zanussi <zanussi@kernel.org>
Subject: [PATCH] tracing: Have traceon and traceoff trigger honor the
 instance
Message-ID: <20220223223837.14f94ec3@rorschach.local.home>
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From: "Steven Rostedt (Google)" <rostedt@goodmis.org>

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.

Cc: stable@vger.kernel.org
Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 kernel/trace/trace_events_trigger.c | 52 +++++++++++++++++++++++++----
 1 file changed, 46 insertions(+), 6 deletions(-)

diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index e0d50c9577f3..efe563140f27 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -1295,6 +1295,16 @@ traceon_trigger(struct event_trigger_data *data,
 		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;
 
@@ -1306,8 +1316,15 @@ traceon_count_trigger(struct event_trigger_data *data,
 		      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;
@@ -1315,7 +1332,10 @@ traceon_count_trigger(struct event_trigger_data *data,
 	if (data->count != -1)
 		(data->count)--;
 
-	tracing_on();
+	if (file)
+		tracer_tracing_on(file->tr);
+	else
+		tracing_on();
 }
 
 static void
@@ -1323,6 +1343,16 @@ traceoff_trigger(struct event_trigger_data *data,
 		 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;
 
@@ -1334,8 +1364,15 @@ traceoff_count_trigger(struct event_trigger_data *data,
 		       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;
@@ -1343,7 +1380,10 @@ traceoff_count_trigger(struct event_trigger_data *data,
 	if (data->count != -1)
 		(data->count)--;
 
-	tracing_off();
+	if (file)
+		tracer_tracing_off(file->tr);
+	else
+		tracing_off();
 }
 
 static int
-- 
2.34.1