| Message ID | 20250509022554.27001-1-zhangzihuan@kylinos.cn |
|---|---|
| State | New |
| Headers | show |
| Series | [v1] HID: debug: Use the __set_current_state() | expand |
diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c index 8433306148d5..00a73983ef19 100644 --- 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; }
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> --- drivers/hid/hid-debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)