Re: [Xen-devel] [PATCH 1/2] xen/rwlocks: call preempt_disable() when taking a rwlock

[Julien Grall <julien@xxxxxxx>]

On 13/03/2020 08:48, Jan Beulich wrote:
> On 13.03.2020 09:05, Juergen Gross wrote:
> > Similar to spinlocks preemption should be disabled while holding a
> > rwlock.
> >
> > Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> Just one note/question:
>
> > @@ -308,6 +323,7 @@ static inline void _percpu_read_unlock(percpu_rwlock_t 
> > **per_cpudata,
> >           return;
> >       }
> >       this_cpu_ptr(per_cpudata) = NULL;
> > +    preempt_enable();
> >       smp_wmb();
> >   }
> It would seem more logical to me to insert this after the smp_wmb().
+1

> Thoughts? I'll be happy to give my R-b once we've settled on this.
>
> Jan
--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel