virtio-ccw: range check in READ_VQ_CONF

[qemu.git] / numa.c

diff --git a/numa.c b/numa.c
index 6b4ab0eae4570e50b121073d56b079cfbc486465..c975fb268232a72b1e9d74ba78ef00c67b4b8931 100644 (file)
--- a/numa.c
+++ b/numa.c
@@ -167,7 +167,52 @@ error:
     return -1;
 }
 
-void parse_numa_opts(void)
+static char *enumerate_cpus(unsigned long *cpus, int max_cpus)
+{
+    int cpu;
+    bool first = true;
+    GString *s = g_string_new(NULL);
+
+    for (cpu = find_first_bit(cpus, max_cpus);
+        cpu < max_cpus;
+        cpu = find_next_bit(cpus, max_cpus, cpu + 1)) {
+        g_string_append_printf(s, "%s%d", first ? "" : " ", cpu);
+        first = false;
+    }
+    return g_string_free(s, FALSE);
+}
+
+static void validate_numa_cpus(void)
+{
+    int i;
+    DECLARE_BITMAP(seen_cpus, MAX_CPUMASK_BITS);
+
+    bitmap_zero(seen_cpus, MAX_CPUMASK_BITS);
+    for (i = 0; i < nb_numa_nodes; i++) {
+        if (bitmap_intersects(seen_cpus, numa_info[i].node_cpu,
+                              MAX_CPUMASK_BITS)) {
+            bitmap_and(seen_cpus, seen_cpus,
+                       numa_info[i].node_cpu, MAX_CPUMASK_BITS);
+            error_report("CPU(s) present in multiple NUMA nodes: %s",
+                         enumerate_cpus(seen_cpus, max_cpus));;
+            exit(EXIT_FAILURE);
+        }
+        bitmap_or(seen_cpus, seen_cpus,
+                  numa_info[i].node_cpu, MAX_CPUMASK_BITS);
+    }
+
+    if (!bitmap_full(seen_cpus, max_cpus)) {
+        char *msg;
+        bitmap_complement(seen_cpus, seen_cpus, max_cpus);
+        msg = enumerate_cpus(seen_cpus, max_cpus);
+        error_report("warning: CPU(s) not present in any NUMA nodes: %s", msg);
+        error_report("warning: All CPU(s) up to maxcpus should be described "
+                     "in NUMA config");
+        g_free(msg);
+    }
+}
+
+void parse_numa_opts(MachineClass *mc)
 {
     int i;
 
@@ -235,15 +280,25 @@ void parse_numa_opts(void)
                 break;
             }
         }
-        /* assigning the VCPUs round-robin is easier to implement, guest OSes
-         * must cope with this anyway, because there are BIOSes out there in
-         * real machines which also use this scheme.
+        /* Historically VCPUs were assigned in round-robin order to NUMA
+         * nodes. However it causes issues with guest not handling it nice
+         * in case where cores/threads from a multicore CPU appear on
+         * different nodes. So allow boards to override default distribution
+         * rule grouping VCPUs by socket so that VCPUs from the same socket
+         * would be on the same node.
          */
         if (i == nb_numa_nodes) {
             for (i = 0; i < max_cpus; i++) {
-                set_bit(i, numa_info[i % nb_numa_nodes].node_cpu);
+                unsigned node_id = i % nb_numa_nodes;
+                if (mc->cpu_index_to_socket_id) {
+                    node_id = mc->cpu_index_to_socket_id(i) % nb_numa_nodes;
+                }
+
+                set_bit(i, numa_info[node_id].node_cpu);
             }
         }
+
+        validate_numa_cpus();
     }
 }