[Qemu-devel] [RFC 2 PATCH 16/16] hw/core: Fix up the machine_set_cpu_numa_node for epyc

["Moger, Babu" <Babu.Moger@amd.com>]

Current topology id match will not work for epyc mode when setting
the node id. In epyc mode, ids like smt_id, thread_id, core_id,
ccx_id, socket_id can be same for more than one CPUs with across
two numa nodes.

For example, we can have two CPUs with following ids on two different node.
1. smt_id=0, thread_id=0, core_id=0, ccx_id=0, socket_id=0, node_id=0
2. smt_id=0, thread_id=0, core_id=0, ccx_id=0, socket_id=0, node_id=1

The function machine_set_cpu_numa_node will fail to find a match to assign
the node. Added new function machine_set_cpu_numa_node_epyc to set the node_id
directly in epyc mode.

Signed-off-by: Babu Moger <babu.moger@amd.com>
---
 hw/core/machine.c   |   24 ++++++++++++++++++++++++
 hw/core/numa.c      |    6 +++++-
 include/hw/boards.h |    4 ++++
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/hw/core/machine.c b/hw/core/machine.c
index 9a8586cf30..6bceefc6f3 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -741,6 +741,30 @@ void machine_set_cpu_numa_node(MachineState *machine,
     }
 }
 
+void machine_set_cpu_numa_node_epyc(MachineState *machine,
+                                    const CpuInstanceProperties *props,
+                                    unsigned index,
+                                    Error **errp)
+{
+    MachineClass *mc = MACHINE_GET_CLASS(machine);
+    CPUArchId *slot;
+
+    if (!mc->possible_cpu_arch_ids) {
+        error_setg(errp, "mapping of CPUs to NUMA node is not supported");
+        return;
+    }
+
+    /* disabling node mapping is not supported, forbid it */
+    assert(props->has_node_id);
+
+    /* force board to initialize possible_cpus if it hasn't been done yet */
+    mc->possible_cpu_arch_ids(machine);
+
+    slot = &machine->possible_cpus->cpus[index];
+    slot->props.node_id = props->node_id;
+    slot->props.has_node_id = props->has_node_id;
+}
+
 static void smp_parse(MachineState *ms, QemuOpts *opts)
 {
     if (opts) {
diff --git a/hw/core/numa.c b/hw/core/numa.c
index 27fa6b5e1d..a9e835aea6 100644
--- a/hw/core/numa.c
+++ b/hw/core/numa.c
@@ -247,7 +247,11 @@ void set_numa_node_options(MachineState *ms, NumaOptions *object, Error **errp)
          props = mc->cpu_index_to_instance_props(ms, cpus->value);
          props.node_id = nodenr;
          props.has_node_id = true;
-         machine_set_cpu_numa_node(ms, &props, &err);
+         if (ms->epyc) {
+             machine_set_cpu_numa_node_epyc(ms, &props, cpus->value, &err);
+         } else {
+             machine_set_cpu_numa_node(ms, &props, &err);
+         }
          if (err) {
             error_propagate(errp, err);
             return;
diff --git a/include/hw/boards.h b/include/hw/boards.h
index 0001d42e50..ec1b1c5a85 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -74,6 +74,10 @@ HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine);
 void machine_set_cpu_numa_node(MachineState *machine,
                                const CpuInstanceProperties *props,
                                Error **errp);
+void machine_set_cpu_numa_node_epyc(MachineState *machine,
+                                    const CpuInstanceProperties *props,
+                                    unsigned index,
+                                    Error **errp);
 
 void machine_class_allow_dynamic_sysbus_dev(MachineClass *mc, const char *type);