[PATCH v4 15/15] security/landlock: convert thread iterator to for_each_thread_rculock

[Ye Liu <ye.liu@linux.dev>]

From: Ye Liu <liuye@kylinos.cn>

Replace guard(rcu)() + for_each_thread() with for_each_thread_rculock(),
which scopes the RCU read lock to the loop body via scoped_guard(rcu).

No functional change.

Signed-off-by: Ye Liu <liuye@kylinos.cn>
Reviewed-by: Justin Suess <utilityemal77@gmail.com>
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Reviewed-by: Gregory Price (Meta) <gourry@gourry.net>
Reviewed-by: SJ Park <sj@kernel.org>
Reviewed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
---
 security/landlock/tsync.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/security/landlock/tsync.c b/security/landlock/tsync.c
index 0b71e158c3f5..a578af640aad 100644
--- a/security/landlock/tsync.c
+++ b/security/landlock/tsync.c
@@ -335,9 +335,7 @@ static size_t count_additional_threads(const struct tsync_works *works)
 
 	caller = current;
 
-	guard(rcu)();
-
-	for_each_thread(caller, thread) {
+	for_each_thread_rculock(caller, thread) {
 		/* Skip current, since it is initiating the sync. */
 		if (thread == caller)
 			continue;
@@ -376,9 +374,7 @@ static bool schedule_task_work(struct tsync_works *works,
 
 	caller = current;
 
-	guard(rcu)();
-
-	for_each_thread(caller, thread) {
+	for_each_thread_rculock(caller, thread) {
 		/* Skip current, since it is initiating the sync. */
 		if (thread == caller)
 			continue;
-- 
2.25.1