void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
u32 iterations = 0;
- while (arch_spin_is_locked(lock))
+ u32 val = READ_ONCE(lock->lock);
+ u32 curr = arch_spin_current(val);
+
+ /* Return immediately if unlocked. */
+ if (arch_spin_next(val) == curr)
+ return;
+
+ /* Wait until the current locker has released the lock. */
+ do {
delay_backoff(iterations++);
+ } while (arch_spin_current(READ_ONCE(lock->lock)) == curr);
}
EXPORT_SYMBOL(arch_spin_unlock_wait);