motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-04 00:03:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

numa: move source of default CPUs to NUMA node mapping into boards

Browse source 
Originally CPU threads were by default assigned in
round-robin fashion. However it was causing issues in
guest since CPU threads from the same socket/core could
be placed on different NUMA nodes.
Commit fb43b73b (pc: fix default VCPU to NUMA node mapping)
fixed it by grouping threads within a socket on the same node
introducing cpu_index_to_socket_id() callback and commit
20bb648d (spapr: Fix default NUMA node allocation for threads)
reused callback to fix similar issues for SPAPR machine
even though socket doesn't make much sense there.

As result QEMU ended up having 3 default distribution rules
used by 3 targets /virt-arm, spapr, pc/.

In effort of moving NUMA mapping for CPUs into possible_cpus,
generalize default mapping in numa.c by making boards decide
on default mapping and let them explicitly tell generic
numa code to which node a CPU thread belongs to by replacing
cpu_index_to_socket_id() with @cpu_index_to_instance_props()
which provides default node_id assigned by board to specified
cpu_index.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1494415802-227633-2-git-send-email-imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
This commit is contained in:
Igor Mammedov 2017-05-10 13:29:45 +02:00 • committed by Eduardo Habkost
parent d9c34f9c6c
commit ea089eebbd
7 changed files with 75 additions and 32 deletions
Download patch file Download diff file Expand all files Collapse all files

20
hw/arm/virt.c
View file

@ -1539,6 +1539,16 @@ static void virt_set_gic_version(Object *obj, const char *value, Error **errp)
}
}
static CpuInstanceProperties
virt_cpu_index_to_props(MachineState *ms, unsigned cpu_index)
{
MachineClass *mc = MACHINE_GET_CLASS(ms);
const CPUArchIdList *possible_cpus = mc->possible_cpu_arch_ids(ms);
assert(cpu_index < possible_cpus->len);
return possible_cpus->cpus[cpu_index].props;
}
static const CPUArchIdList *virt_possible_cpu_arch_ids(MachineState *ms)
{
int n;
@ -1558,8 +1568,13 @@ static const CPUArchIdList *virt_possible_cpu_arch_ids(MachineState *ms)
ms->possible_cpus->cpus[n].props.has_thread_id = true;
ms->possible_cpus->cpus[n].props.thread_id = n;
/* TODO: add 'has_node/node' here to describe
to which node core belongs */
/* default distribution of CPUs over NUMA nodes */
if (nb_numa_nodes) {
/* preset values but do not enable them i.e. 'has_node_id = false',
* numa init code will enable them later if manual mapping wasn't
* present on CLI */
ms->possible_cpus->cpus[n].props.node_id = n % nb_numa_nodes;
}
}
return ms->possible_cpus;
}
@ -1581,6 +1596,7 @@ static void virt_machine_class_init(ObjectClass *oc, void *data)
/* We know we will never create a pre-ARMv7 CPU which needs 1K pages */
mc->minimum_page_bits = 12;
mc->possible_cpu_arch_ids = virt_possible_cpu_arch_ids;
mc->cpu_index_to_instance_props = virt_cpu_index_to_props;
}
static const TypeInfo virt_machine_info = {