binder: use guards for plain mutex- and spinlock-protected sections

Use 'guard(mutex)' and 'guard(spinlock)' for plain (i.e. non-scoped)
mutex- and spinlock-protected sections, respectively, thus making
locking a bit simpler. Briefly tested with 'stress-ng --binderfs'.

Signed-off-by: Dmitry Antipov <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Acked-by: Carlos Llamas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

1 files changed, 2 insertions, 6 deletions

diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h
index feecd7414241..a9d5f3169e12 100644
--- a/drivers/android/binder_alloc.h
+++ b/drivers/android/binder_alloc.h
@@ -160,12 +160,8 @@ void binder_alloc_print_pages(struct seq_file *m,
 static inline size_t
 binder_alloc_get_free_async_space(struct binder_alloc *alloc)
 {
-	size_t free_async_space;
-
-	mutex_lock(&alloc->mutex);
-	free_async_space = alloc->free_async_space;
-	mutex_unlock(&alloc->mutex);
-	return free_async_space;
+	guard(mutex)(&alloc->mutex);
+	return alloc->free_async_space;
 }
 
 unsigned long