HID: debug: Use the __set_current_state()

When detecting an invalid list->hdev, the process needs to manually set
its state to TASK_RUNNING and exit. In the original code,
set_current_state() (which includes a memory barrier) is used here, but
it is immediately followed by a mutex_unlock() call. Since
mutex_unlock() internally includes a memory barrier, this ensures that
all modifications within the critical section (including the process
state) are visible to other CPUs. Therefore, replacing it with
__set_current_state() (without an implicit barrier) avoids redundant
memory barriers.

Signed-off-by: Zihuan Zhang <zhangzihuan@kylinos.cn>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index 8433306148d57887f855578b8386bd0473cad612..00a73983ef19b107ee7be8e2e6b854873e0dc333 100644 (file)
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -3726,7 +3726,7 @@ static ssize_t hid_debug_events_read(struct file *file, char __user *buffer,
                         */
                        if (!list->hdev || !list->hdev->debug) {
                                ret = -EIO;
-                               set_current_state(TASK_RUNNING);
+                               __set_current_state(TASK_RUNNING);
                                goto out;
                        }