On 02/12, Raghavendra K T wrote: > > @@ -191,8 +189,7 @@ static inline void arch_spin_unlock_wait(arch_spinlock_t *lock) > * We need to check "unlocked" in a loop, tmp.head == head > * can be false positive because of overflow. > */ > - if (tmp.head == (tmp.tail & ~TICKET_SLOWPATH_FLAG) || > - tmp.head != head) > + if (__tickets_equal(tmp.head, tmp.tail) || tmp.head != head) > break; Ah, it seems that "tmp.head != head" should be turned into !__tickets_equal(), no? Suppose that TICKET_SLOWPATH_FLAG is set after the first ACCESS_ONCE(head), then tmp.head != head will be true before the first unlock we are waiting for. And perhaps you can turn these ACCESS_ONCE into READ_ONCE as well. Oleg. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
