On Tue, Nov 07, 2017 at 04:04:04PM +0100, Cornelia Huck wrote: > On Mon, 6 Nov 2017 16:02:16 -0200 > Eduardo Habkost <ehabk...@redhat.com> wrote: > > > On Tue, Oct 31, 2017 at 03:01:14PM +0100, Igor Mammedov wrote: > > > On Thu, 19 Oct 2017 17:31:51 +1100 > > > David Gibson <da...@gibson.dropbear.id.au> wrote: > > > > > > > On Wed, Oct 18, 2017 at 01:12:12PM +0200, Igor Mammedov wrote: > > > > > For enabling early cpu to numa node configuration at runtime > > > > > qmp_query_hotpluggable_cpus() should provide a list of available > > > > > cpu slots at early stage, before machine_init() is called and > > > > > the 1st cpu is created, so that mgmt might be able to call it > > > > > and use output to set numa mapping. > > > > > Use MachineClass::possible_cpu_arch_ids() callback to set > > > > > cpu type info, along with the rest of possible cpu properties, > > > > > to let machine define which cpu type* will be used. > > > > > > > > > > * for SPAPR it will be a spapr core type and for ARM/s390x/x86 > > > > > a respective descendant of CPUClass. > > > > > > > > > > Move parse_numa_opts() in vl.c after cpu_model is parsed into > > > > > cpu_type so that possible_cpu_arch_ids() would know which > > > > > cpu_type to use during layout initialization. > > > > > > > > > > Signed-off-by: Igor Mammedov <imamm...@redhat.com> > > > > > > > > Reviewed-by: David Gibson <da...@gibson.dropbear.id.au> > > > > > > > > > --- > > > > > v2: > > > > > - fix NULL dereference caused by not initialized > > > > > MachineState::cpu_type at the time parse_numa_opts() > > > > > were called > > > > > --- > > > > > include/hw/boards.h | 2 ++ > > > > > hw/arm/virt.c | 3 ++- > > > > > hw/core/machine.c | 12 ++++++------ > > > > > hw/i386/pc.c | 4 +++- > > > > > hw/ppc/spapr.c | 13 ++++++++----- > > > > > hw/s390x/s390-virtio-ccw.c | 1 + > > > > > vl.c | 3 +-- > > > > > 7 files changed, 23 insertions(+), 15 deletions(-) > > > > > > > > > > diff --git a/include/hw/boards.h b/include/hw/boards.h > > > > > index 191a5b3..fa21758 100644 > > > > > --- a/include/hw/boards.h > > > > > +++ b/include/hw/boards.h > > > > > @@ -80,6 +80,7 @@ void machine_set_cpu_numa_node(MachineState > > > > > *machine, > > > > > * CPUArchId: > > > > > * @arch_id - architecture-dependent CPU ID of present or possible > > > > > CPU > > > > > > > > I know this isn't really in scope for this patch, but is @arch_id here > > > > supposed to have meaning defined by the target, or by the machine? > > > > > > > > If it's the machime, it could do with a rename - "arch" means target > > > > to most people (thanks to Linux). > > > > > > > > If it's the target, it's kind of bogus, because it doesn't necessarily > > > > have a clear meaning per target - get_arch_id in CPUClass has the same > > > > problem, which is probably one reason it's basically only used by the > > > > x86 code at present. > > > > > > > > e.g. for target/ppc, what do we use? There's the PIR, which is in the > > > > CPU.. but only on some cpu models, not all. There will generally be > > > > some kind of master PIC id, but there are different PIC models on > > > > different boards. What goes in the devicetree? Well only some > > > > machines use devicetree, and they might define the cpu reg > > > > differently. > > > > > > > > Board designs will generally try to make some if not all of those > > > > possible values equal for simplicity, but there's still no real way of > > > > defining a sensible arch_id independent of machine / board. > > > I'd say arch_id is machine specific so far, it was introduced when we > > > didn't have CpuInstanceProperties and at that time we considered only > > > vcpus (threads) and doesn't really apply to spapr cores. > > > > > > In general we could do away with arch_id and use CpuInstanceProperties > > > instead, but arch_id also serves aux purpose, it allows machine to > > > pre-calculate(cache) apic-id/mpidr values in one place and then they > > > are/(could be) used by arch in-depended code to build acpi tables. > > > So if we drop arch_id we would need to introduce a machine hook, > > > which would translate CpuInstanceProperties into current arch_id. > > > > I think we need to do a better to job documenting where exactly > > we expect arch_id to be used and how, so people know what it's > > supposed to return. > > > > If the only place where it's useful now is ACPI code (is it?), > > should we rename it to something like get_acpi_id()? > > It is also used in hw/s390x/sclp.c to fill out a control block, so acpi > isn't the only user.
Yeah.. this is kind of bogus. The s390 use is in machine specific
code, so it's basically just re-using the field for an unrelated usage
to the x86/arm one (ACPI).
If we can't assign a universal meaning to the field (even if the
actual values are per-machine) - and I don't think we can - then I
really don't think it belongs in CPUState. A machine hook which
translates an ArchId to an acpi_id is the correct solution I believe.
Or even an ACPIMachine interface (to be implemented by machines which
do ACPI) which has a method to do this.
Since both the assignment and use are in machine type specific code
for s390, it can have its own field in the s390 specific cpu subclass.
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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