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

[Xen-devel] Re: [Xen-changelog] Create new vcpu_op() hypercall. Replaces old boot_vcpu()

On 3 Oct 2005, at 19:42, Ryan Harper wrote:

Both do_boot_vcpu() and now VCPU_CREATE rely on domU kernel playing nice
and not making the hypercall more than has been indicated in the shared
table when we built the domain (nr_vcpus).  Wouldn't it be better to
have the domain creation hypercall specify the number of vcpus for a
domain (as well as a cpumap to indicate which physical cpus are to be
used) and alloc vcpu structures at that point leaving the vcpu_ops() to
get context and unpause the vcpu?

If I put together a patch that mode the above change, would that be

I think there's not much in it -- allocating on demand vs. allocate at domain build time. I think the simplest patch would be for Xen to be passed a max_vcpuid or max_vcpus and apply the appropriate simple check at VCPUOP_create.

I'd take a patch that adds a new dom0 op to set that value (DOM0_SET_MAX_VCPUS or somesuch), applies the appropriate check inside Xen. Also that plumbs that hypercall into the Python wrapper, and adds a call to that command in xend (both during initial build and on save/restore).

 -- Keir

Xen-devel mailing list



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