[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH 3/3] evtchn/fifo: don't spin indefinitely when setting LINK

On 06/11/13 15:01, Boris Ostrovsky wrote:
> On 11/06/2013 08:38 AM, David Vrabel wrote:
>> Given the non-obvious locking required for this to be safe and the
>> overhead of the guest having to do a unmask hypercall more often.  I
>> think I will fix this differently.
>> A new BUSY bit is added to the event word.  Xen sets BUSY prior to
>> updating the LINK field and then clears it when the LINK field is set.
>> When the guest unmasks an event it must spin waiting for BUSY to clear
>> before it clears the MASKED bit.  It then need only do the unmask
>> hypercall if the event is pending (as before).
>> Draft H and v3 of this series to follow.
> Will there be a new Linux series as well?

Yes, but only the final patch in the series will change.


Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.