atomic64_add(__SIX_VAL(write_locking, 1),
&lock->state.counter);
smp_mb__after_atomic();
+ } else if (!(lock->state.waiters & (1 << SIX_LOCK_write))) {
+ atomic64_add(__SIX_VAL(waiters, 1 << SIX_LOCK_write),
+ &lock->state.counter);
+ /*
+ * pairs with barrier after unlock and before checking
+ * for readers in unlock path
+ */
+ smp_mb__after_atomic();
}
ret = !pcpu_read_count(lock);
if (ret || try)
v -= __SIX_VAL(write_locking, 1);
- if (!ret && !try && !(lock->state.waiters & (1 << SIX_LOCK_write)))
- v += __SIX_VAL(waiters, 1 << SIX_LOCK_write);
-
if (try && !ret) {
old.v = atomic64_add_return(v, &lock->state.counter);
six_lock_wakeup(lock, old, SIX_LOCK_read);