audit: use atomic_t to simplify audit_serial()

Since there is already a primitive to do this operation in the atomic_t, use it
to simplify audit_serial().

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>

1 files changed, 2 insertions, 12 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
index 8a82d481393d..7aef7cbd7bcf 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1301,19 +1301,9 @@ err:
  */
 unsigned int audit_serial(void)
 {
-        static DEFINE_SPINLOCK(serial_lock);
-        static unsigned int serial = 0;
+        static atomic_t serial = ATOMIC_INIT(0);
 
-        unsigned long flags;
-        unsigned int ret;
-
-        spin_lock_irqsave(&serial_lock, flags);
-        do {
-                ret = ++serial;
-        } while (unlikely(!ret));
-        spin_unlock_irqrestore(&serial_lock, flags);
-
-        return ret;
+        return atomic_add_return(1, &serial);
 }
 
 static inline void audit_get_stamp(struct audit_context *ctx,