conf: numa: Add helper to get guest NUMA node count and refactor users

Add an accessor so that a later refactor is simpler.

src/conf/domain_conf.c

@@ -13531,7 +13531,7 @@ virDomainDefParseXML(xmlDocPtr xml,
     if (virDomainNumatuneParseXML(def->numa,
                                   def->placement_mode ==
                                   VIR_DOMAIN_CPU_PLACEMENT_MODE_STATIC,
-                                  def->cpu ? def->cpu->ncells : 0,
+                                  virDomainNumaGetNodeCount(def->cpu),
                                   ctxt) < 0)
         goto error;
 

src/conf/numa_conf.c

@@ -760,14 +760,15 @@ virDomainNumaDefCPUFormat(virBufferPtr buf,
 {
     virNumaMemAccess memAccess;
     char *cpustr;
+    size_t ncells = virDomainNumaGetNodeCount(def);
     size_t i;
 
-    if (def->ncells == 0)
+    if (ncells == 0)
         return 0;
 
     virBufferAddLit(buf, "<numa>\n");
     virBufferAdjustIndent(buf, 2);
-    for (i = 0; i < def->ncells; i++) {
+    for (i = 0; i < ncells; i++) {
         memAccess = def->cells[i].memAccess;
 
         if (!(cpustr = virBitmapFormat(def->cells[i].cpumask)))
@@ -813,3 +814,13 @@ virDomainNumaNew(void)
 
     return ret;
 }
+
+
+size_t
+virDomainNumaGetNodeCount(virCPUDefPtr numa)
+{
+    if (!numa)
+        return 0;
+
+    return numa->ncells;
+}

src/conf/numa_conf.h

@@ -86,6 +86,9 @@ int virDomainNumatuneMaybeGetNodeset(virDomainNumaPtr numatune,
                                      virBitmapPtr *retNodeset,
                                      int cellid);
 
+size_t virDomainNumaGetNodeCount(virCPUDefPtr numa)
+    ATTRIBUTE_NONNULL(1);
+
 /*
  * Formatters
  */

src/libvirt_private.syms

@@ -629,6 +629,7 @@ virNodeDeviceObjUnlock;
 # conf/numa_conf.h
 virDomainNumaEquals;
 virDomainNumaFree;
+virDomainNumaGetNodeCount;
 virDomainNumaNew;
 virDomainNumatuneFormatNodeset;
 virDomainNumatuneFormatXML;

src/qemu/qemu_command.c

@@ -7121,7 +7121,7 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg,
     bool needBackend = false;
     int rc;
     int ret = -1;
-    size_t ncells = def->cpu->ncells;
+    size_t ncells = virDomainNumaGetNodeCount(def->cpu);
     const long system_page_size = virGetSystemPageSizeKB();
 
     if (virDomainNumatuneHasPerNodeBinding(def->numa) &&
@@ -8318,7 +8318,7 @@ qemuBuildCommandLine(virConnectPtr conn,
     virCommandAddArg(cmd, "-m");
     def->mem.max_balloon = VIR_DIV_UP(def->mem.max_balloon, 1024) * 1024;
     virCommandAddArgFormat(cmd, "%llu", def->mem.max_balloon / 1024);
-    if (def->mem.nhugepages && (!def->cpu || !def->cpu->ncells)) {
+    if (def->mem.nhugepages && !virDomainNumaGetNodeCount(def->cpu)) {
         const long system_page_size = virGetSystemPageSizeKB();
         char *mem_path = NULL;
 
@@ -8398,7 +8398,7 @@ qemuBuildCommandLine(virConnectPtr conn,
         }
     }
 
-    if (def->cpu && def->cpu->ncells)
+    if (virDomainNumaGetNodeCount(def->cpu))
         if (qemuBuildNumaArgStr(cfg, def, cmd, qemuCaps, nodeset) < 0)
             goto error;