Re: ia64 event channels

[Arun Sharma <arun.sharma@intel.com>]

Matt Chapman wrote:
> This is the one change we've made to architecture-independent code
> for event channels.  Rather than polling the event channel flags
> on every return, we pend an interrupt in evtchn_set_pending.
> 
> This might be better abstracted into some architecture-dependent
> header file, but I'm not sure where.  We could add an asm/event.h,
> though it does seem a bit excessive to add a file just for one
> trivial hook.

Not all event channel events get injected into the guest. For eg, on 
VT-x and VT-i, we use event channels to communicate events from the 
device models to the hypervisor on handling memory mapped and accesses 
to I/O ports.

Have you already looked at this patch:

http://article.gmane.org/gmane.comp.emulators.xen.devel/10852

vmx_check_guest_event() does something very similar.

Also, it might be good to unify the names (callback_irq vs evtchn_vector 
-- I like evtchn_vector better).

	-Arun