RE: [Xen-ia64-devel] [RFC][PATCH] hypercall_preempt_check() and psr.i

[Alex Williamson <alex.williamson@xxxxxx>]

On Wed, 2006-03-29 at 22:14 +0800, Tian, Kevin wrote:
> Hi, Isaku,
>       Seems we're shooting same issue by different way. In the beginning, 
> I also came up same simple approach as yours. However after more 
> thinking, I think it's better to tune xen/ia64 to adapt to common concept 
> where evtchn_upcall_mask is the flag whether events/interrupts can be 
> injected into guest. Or else we have to add similar #ifdef as yours time to 
> time, which especially only be observed when important bugs are tracked 
> down after many debugs.

   The simplicity and compact-ness of Isaku's patch is certainly
appealing.  What if instead of fixing this one case with a #ifdef we
were to something like this:

#define event_pending(v)                         \
    ((!!(v)->vcpu_info->evtchn_upcall_pending &  \
       !(v)->vcpu_info->evtchn_upcall_mask)) &&  \
      arch_event_pending(v))

x86:

#define arch_event_pending(v) (1)

ia64:

#define arch_event_pending(v) (PSCB(v, interrupt_delivery_enabled))

Thanks,

    Alex

-- 
Alex Williamson                             HP Linux & Open Source Lab


_______________________________________________
Xen-ia64-devel mailing list
Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ia64-devel