On Tue, May 23, 2017 at 05:44:03PM +0200, Igor Mammedov wrote: > On Tue, 23 May 2017 11:48:54 -0300 > Eduardo Habkost <ehabk...@redhat.com> wrote: > > > On Tue, May 23, 2017 at 04:38:49PM +0200, Igor Mammedov wrote: > > > Do the same as we did in commit > > > (57924bcd8 numa: introduce machine callback for VCPU to node mapping) > > > but only for incomplete mapping usecase, falling back to board > > > provided default cpu to node mapping if user hasn't provided > > > mapping for CPU explicitly. > > > > > > Signed-off-by: Igor Mammedov <imamm...@redhat.com> > > > > This breaks migration compatibility, doesn't it? I understand > > this use case is not supported, but if are going to break stuff > > for people using incomplete mappings (by rejecting the > > configuration on a future release), I would prefer to break it > > only once. > it's firmware change and we generally don't care nor maintain firmware compat > stuff > the same as with above mentioned > (57924bcd8 numa: introduce machine callback for VCPU to node mapping)
We normally keep resulting NUMA topology compatible, even if NUMA information is implemented only by firmware. See how we set MachineClass::numa_auto_assign_ram and MachineClass::numa_mem_align_shift in older machine-types, for example. Sometimes we didn't keep compatibility, though (e.g. on commit fb43b73b92 "pc: fix default VCPU to NUMA node mapping"). I wouldn't disagree with this change if we planned to support incomplete mappings forever. But if we are going to remove support for incomplete mappings soon, I would prefer to break user expectations only once. > > > > > > --- > > > hw/core/machine.c | 3 --- > > > 1 file changed, 3 deletions(-) > > > > > > diff --git a/hw/core/machine.c b/hw/core/machine.c > > > index 964b75d..b8df15f 100644 > > > --- a/hw/core/machine.c > > > +++ b/hw/core/machine.c > > > @@ -730,9 +730,6 @@ static void machine_numa_finish_init(MachineState > > > *machine) > > > g_string_append_printf(s, "%sCPU %d [%s]", > > > s->len ? ", " : "", i, cpu_str); > > > g_free(cpu_str); > > > - > > > - /* non mapped cpus used to fallback to node 0 */ > > > - props.node_id = 0; > > > } > > > > > > props.has_node_id = true; > > > -- > > > 2.7.4 > > > > > > > -- Eduardo
