tracing: Replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lkml.kernel.org/r/20220427170734.819891-4-jakobkoschel@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

1 files changed, 7 insertions, 8 deletions

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index fe10179893c1..038dc591545d 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -6117,20 +6117,19 @@ static void hist_unregister_trigger(char *glob,
 				    struct event_trigger_data *data,
 				    struct trace_event_file *file)
 {
+	struct event_trigger_data *test = NULL, *iter, *named_data = NULL;
 	struct hist_trigger_data *hist_data = data->private_data;
-	struct event_trigger_data *test, *named_data = NULL;
-	bool unregistered = false;
 
 	lockdep_assert_held(&event_mutex);
 
 	if (hist_data->attrs->name)
 		named_data = find_named_trigger(hist_data->attrs->name);
 
-	list_for_each_entry(test, &file->triggers, list) {
-		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
-			if (!hist_trigger_match(data, test, named_data, false))
+	list_for_each_entry(iter, &file->triggers, list) {
+		if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+			if (!hist_trigger_match(data, iter, named_data, false))
 				continue;
-			unregistered = true;
+			test = iter;
 			list_del_rcu(&test->list);
 			trace_event_trigger_enable_disable(file, 0);
 			update_cond_flag(file);
@@ -6138,11 +6137,11 @@ static void hist_unregister_trigger(char *glob,
 		}
 	}
 
-	if (unregistered && test->ops->free)
+	if (test && test->ops->free)
 		test->ops->free(test);
 
 	if (hist_data->enable_timestamps) {
-		if (!hist_data->remove || unregistered)
+		if (!hist_data->remove || test)
 			tracing_set_filter_buffering(file->tr, false);
 	}
 }