From: Igor Mammedov <imammedo@redhat.com>
Date: Fri, 24 Feb 2017 09:26:56 +0000 (+0100)
Subject: spapr: ensure that all threads within core are on the same NUMA node
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=17b7c39e275ecacae1416bc164189d6ddd116c57;p=qemu.git

spapr: ensure that all threads within core are on the same NUMA node

Threads within a core shouldn't be on different
NUMA nodes, so if user has misconfgured command
line, fail QEMU at start up to force user fix it.

For now use the first thread on the core as source
of core's node-id. Later when cpu-numa refactoring
lands  it will be switched to core's node-id from
possible_cpus[].

This prevents the same problems as commit 20bb648d
"spapr: Fix default NUMA node allocation for threads",
but for the case of manually configured NUMA node
mappings, instead of just the default case.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---

diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
index d37832d0e3..6883f0991a 100644
--- a/hw/ppc/spapr_cpu_core.c
+++ b/hw/ppc/spapr_cpu_core.c
@@ -63,8 +63,6 @@ static void spapr_cpu_init(sPAPRMachineState *spapr, PowerPCCPU *cpu,
                            Error **errp)
 {
     CPUPPCState *env = &cpu->env;
-    CPUState *cs = CPU(cpu);
-    int i;
 
     /* Set time-base frequency to 512 MHz */
     cpu_ppc_tb_init(env, SPAPR_TIMEBASE_FREQ);
@@ -82,12 +80,6 @@ static void spapr_cpu_init(sPAPRMachineState *spapr, PowerPCCPU *cpu,
         }
     }
 
-    /* Set NUMA node for the added CPUs  */
-    i = numa_get_node_for_cpu(cs->cpu_index);
-    if (i < nb_numa_nodes) {
-            cs->numa_node = i;
-    }
-
     xics_cpu_setup(XICS_FABRIC(spapr), cpu);
 
     qemu_register_reset(spapr_cpu_reset, cpu);
@@ -171,11 +163,13 @@ static void spapr_cpu_core_realize(DeviceState *dev, Error **errp)
     const char *typename = object_class_get_name(scc->cpu_class);
     size_t size = object_type_get_instance_size(typename);
     Error *local_err = NULL;
+    int core_node_id = numa_get_node_for_cpu(cc->core_id);;
     void *obj;
     int i, j;
 
     sc->threads = g_malloc0(size * cc->nr_threads);
     for (i = 0; i < cc->nr_threads; i++) {
+        int node_id;
         char id[32];
         CPUState *cs;
 
@@ -184,6 +178,19 @@ static void spapr_cpu_core_realize(DeviceState *dev, Error **errp)
         object_initialize(obj, size, typename);
         cs = CPU(obj);
         cs->cpu_index = cc->core_id + i;
+
+        /* Set NUMA node for the added CPUs  */
+        node_id = numa_get_node_for_cpu(cs->cpu_index);
+        if (node_id != core_node_id) {
+            error_setg(&local_err, "Invalid node-id=%d of thread[cpu-index: %d]"
+                " on CPU[core-id: %d, node-id: %d], node-id must be the same",
+                 node_id, cs->cpu_index, cc->core_id, core_node_id);
+            goto err;
+        }
+        if (node_id < nb_numa_nodes) {
+            cs->numa_node = node_id;
+        }
+
         snprintf(id, sizeof(id), "thread[%d]", i);
         object_property_add_child(OBJECT(sc), id, obj, &local_err);
         if (local_err) {