[PATCH v3 15/15] security/landlock: convert thread iterator to for_each_thread_rculock

From: Ye Liu

Date: Fri Sep 11 2026 - 04:12:51 EST


From: Ye Liu <liuye@xxxxxxxxxx>

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@xxxxxxxxxx>
Reviewed-by: Justin Suess <utilityemal77@xxxxxxxxx>
Reviewed-by: Günther Noack <gnoack3000@xxxxxxxxx>
Reviewed-by: Gregory Price (Meta) <gourry@xxxxxxxxxx>
Reviewed-by: SJ Park <sj@xxxxxxxxxx>
Reviewed-by: Lorenzo Stoakes (ARM) <ljs@xxxxxxxxxx>
---
Changes in v2:
- Rename *_rcu to *_rculock
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