On 30.09.2020 09:58, Paul Durrant wrote:
>> From: Xen-devel <xen-devel-boun...@lists.xenproject.org> On Behalf Of Jan
>> Beulich
>> Sent: 28 September 2020 12:02
>>
>> @@ -334,6 +334,12 @@ void _spin_unlock_recursive(spinlock_t *
>> }
>> }
>>
>> +void _rw_barrier(rwlock_t *lock)
>> +{
>> + check_barrier(&lock->lock.debug);
>> + do { smp_mb(); } while ( _rw_is_locked(lock) );
>> +}
>
> Should you not have a cpu_relax() somewhere in here?
>
> TBH though, the fact this lock is never taken as a writer makes me
> wonder whether there needs to be a lock at all.
For both of these - see the discussion Julien and I also had. The
construct will now move to the subsequent patch anyway, and change
as per Julien's request.
Jan
