search for: slowpath_enter

.... It is nop on x86, just to make this code > more understandable for those (for me ;) who can never remember even the > x86 rules. > Hope you meant it for add_stat. yes smp_mb__after_atomic() would be harmless barrier() in x86. Did not add this V5 as yoiu though but this made me look at slowpath_enter code and added an explicit barrier() there :).

.... It is nop on x86, just to make this code > more understandable for those (for me ;) who can never remember even the > x86 rules. > Hope you meant it for add_stat. yes smp_mb__after_atomic() would be harmless barrier() in x86. Did not add this V5 as yoiu though but this made me look at slowpath_enter code and added an explicit barrier() there :).

Paravirt spinlock clears slowpath flag after doing unlock. As explained by Linus currently it does: prev = *lock; add_smp(&lock->tickets.head, TICKET_LOCK_INC); /* add_smp() is a full mb() */ if (unlikely(lock->tickets.tail & TICKET_SLOWPATH_FLAG)) __ticket_unlock_slowpath(lock, prev); which is

Paravirt spinlock clears slowpath flag after doing unlock. As explained by Linus currently it does: prev = *lock; add_smp(&lock->tickets.head, TICKET_LOCK_INC); /* add_smp() is a full mb() */ if (unlikely(lock->tickets.tail & TICKET_SLOWPATH_FLAG)) __ticket_unlock_slowpath(lock, prev); which is