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

Re: [Xen-devel] [PATCH v14 04/17] Introduce pv guest type and has_hvm_container macros



On 04/11/13 16:20, Jan Beulich wrote:
On 04.11.13 at 13:14, George Dunlap <george.dunlap@xxxxxxxxxxxxx> wrote:
The goal of this patch is to classify conditionals more clearly, as to
whether they relate to pv guests, hvm-only guests, or guests with an
"hvm container" (which will eventually include PVH).

This patch introduces an enum for guest type, as well as two new macros
for switching behavior on and off: is_pv_* and has_hvm_container_*.  At the
moment is_pv_* <=> !has_hvm_container_*.  The purpose of having two is that
it seems to me different to take a path because something does *not* have PV
structures as to take a path because it *does* have HVM structures, even if
the
two happen to coincide 100% at the moment.  The exact usage is occasionally
a bit
fuzzy though, and a judgement call just needs to be made on which is
clearer.

In general, a switch should use is_pv_* (or !is_pv_*) if the code in
question
relates directly to a PV guest.  Examples include use of pv_vcpu structs or
other behavior directly related to PV domains.

hvm_container is more of a fuzzy concept, but in general:
So sadly this is still being retained, despite its redundancy.

I understood our discussion at XenSummit to be that I should send the series as-is, once I had fixed the outstanding bugs. I'm inclined to consider Tim's suggestion (as I understand it), that we get rid of the separate PVH mode, but instead have a number of features which can be enabled and disabled (apic, qemu, &c). But that shouldn't affect the interface to Linux.

 -George

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel


 


Rackspace

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