qemu: directly create virResctrlInfo ignoring capabilities

We always refresh the capabilities object when using virResctrlInfo
during process startup. This is undesirable overhead, because we can
just directly create a virResctrlInfo instead.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

src/qemu/qemu_process.c

@@ -2724,29 +2724,24 @@ qemuProcessSetupEmulator(virDomainObjPtr vm)
 
 
 static int
-qemuProcessResctrlCreate(virQEMUDriverPtr driver,
-                         virDomainObjPtr vm)
+qemuProcessResctrlCreate(virDomainObjPtr vm)
 {
-    int ret = -1;
     size_t i = 0;
-    virCapsPtr caps = NULL;
     qemuDomainObjPrivatePtr priv = vm->privateData;
+    g_autoptr(virResctrlInfo) resctrl = NULL;
 
     if (!vm->def->nresctrls)
         return 0;
 
-    /* Force capability refresh since resctrl info can change
-     * XXX: move cache info into virresctrl so caps are not needed */
-    caps = virQEMUDriverGetCapabilities(driver, true);
-    if (!caps)
+    if (!(resctrl = virResctrlInfoNew()))
         return -1;
 
     for (i = 0; i < vm->def->nresctrls; i++) {
         size_t j = 0;
-        if (virResctrlAllocCreate(caps->host.resctrl,
+        if (virResctrlAllocCreate(resctrl,
                                   vm->def->resctrls[i]->alloc,
                                   priv->machineName) < 0)
-            goto cleanup;
+            return -1;
 
         for (j = 0; j < vm->def->resctrls[i]->nmonitors; j++) {
             virDomainResctrlMonDefPtr mon = NULL;
@@ -2754,14 +2749,11 @@ qemuProcessResctrlCreate(virQEMUDriverPtr driver,
             mon = vm->def->resctrls[i]->monitors[j];
             if (virResctrlMonitorCreate(mon->instance,
                                         priv->machineName) < 0)
-                goto cleanup;
+                return -1;
         }
     }
 
-    ret = 0;
- cleanup:
-    virObjectUnref(caps);
-    return ret;
+    return 0;
 }
 
 
@@ -6882,7 +6874,7 @@ qemuProcessLaunch(virConnectPtr conn,
         goto cleanup;
 
     VIR_DEBUG("Setting up resctrl");
-    if (qemuProcessResctrlCreate(driver, vm) < 0)
+    if (qemuProcessResctrlCreate(vm) < 0)
         goto cleanup;
 
     VIR_DEBUG("Setting up managed PR daemon");

src/util/virresctrl.h

@@ -100,6 +100,8 @@ typedef virResctrlInfo *virResctrlInfoPtr;
 virResctrlInfoPtr
 virResctrlInfoNew(void);
 
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(virResctrlInfo, virObjectUnref);
+
 int
 virResctrlInfoGetCache(virResctrlInfoPtr resctrl,
                        unsigned int level,