>>> On 23.04.15 at 14:03, <t...@xen.org> wrote:
> At 11:11 +0100 on 21 Apr (1429614687), David Vrabel wrote:
>> void _spin_unlock(spinlock_t *lock)
>> {
>> + smp_mb();
>> preempt_enable();
>> LOCK_PROFILE_REL;
>> - _raw_spin_unlock(&lock->raw);
>> + lock->tickets.head++;
>
> This needs to be done with an explicit atomic (though not locked)
> write; otherwise the compiler might use some unsuitable operation that
> clobbers .tail as well.
How do you imagine that to happen? An increment of one
structure member surely won't modify any others.
Jan
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
