Re: [libvirt] [PATCH 08/12] vcpu: support maxvcpu in domain_conf

On 10/01/2010 09:01 AM, Daniel Veillard wrote: >On Wed, Sep 29, 2010 at 06:02:12PM -0600, Eric Blake wrote: >>* src/conf/domain_conf.h (_virDomainDef): Adjust vcpus to unsigned >>short, to match virDomainGetInfo limit. Add maxvcpus member. >[...] >> >>Two tightly-related changes. One: virDomainGetInfo implicitly limits >>vcpus to a 16-bit number; so there's no need to pretend otherwise >>through the rest of the code. > > well, yes and no, in a few years we may look ridiculous, but it would > be good to have the new APIs cleared up from that limitation. So, should I keep the change to 16-bit in my v2 series, or should I keep things at 32-bit and add code that makes virDomainGetInfo fail on 16-bit overflow? Right now, it's easier to keep things at 16-bit throughout. Also, note that the new APIs (virDomainGetVcpusFlags and virDomainSetVcpusFlags) can go up to 31 bits. Get must return -1 on failure, so a full 32-bits cannot be returned; so even though Set passes an unsigned value, we should not accept 0x80000000, even if we decide someday that we want to support 0x10000 vcpus.