[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [RFC PATCH V3 21/22] Only allow extended event channel on Dom0 and driver domains
On Thu, 2013-02-28 at 12:43 +0000, David Vrabel wrote: > On 27/02/13 14:34, Wei Liu wrote: > > For non-Dom0 domains, add a flag to indicate whether it can use extended > > event > > channel, admins can specify this flag when creating a driver domain. > > > > The rationale behide this option is, a) extended event channel will > > consume global mapping space in Xen, b) likely that only Dom0 and driver > > domains need this. > > I would prefer the toolstack to limit the max port that the guest can > use (see the EVTCHNOP_set_limit sub-op I proposed), than this single bit > (which isn't useful for the FIFO-based proposal). > I'm not very keen on adding that EVTCHNOP_set_limit now, because: * limiting number of event channels in 2/3-level brings no significant improvement. * you would need to way to notify guest kernel its limit (be another OP or via Xenstore), because in any case a guest uses user space evtchn driver it would need to know the limit. In any case, the purpose of this option is to indicate whether the guest can use *any* of the extended ABIs. A better naming should be evtchn_extended_allowed, which should default to 1 in FIFO-based ABIs. Wei. > David _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |