On Thu, 18 Feb 2016 10:46:52 +0100 David Hildenbrand <d...@linux.vnet.ibm.com> wrote:
> > > #if !defined(CONFIG_USER_ONLY) > > > +void s390_hot_add_cpu(const int64_t id, Error **errp) > > > +{ > > to make it future-proof wrt migration it could be better to > > enforce here that 'id' grows in +1 steps so user > > won't be able create cpus with gaps. > > That should be already covered by: > > if (id != next_cpu_id) > ... > > or am I missing something? yep, that should do the job, but it might be better to introduce next_cpu_id in this patch so it would be clear were it comes from and how it's used while dropping it completely from previous one. essentially next_cpu_id is (cpu_index + 1) so you don't even need to create a global var, just get the last CPU and to math, something like that: include/qom/cpu.h: +#define last_cpu QTAILQ_LAST(&cpus) if (id != (last_cpu->cpu_index + 1)) { .... } > > David >