[libvirt] [PATCH 1/2] qemu: process: Move emulator thread setting code into one function

[Peter Krempa]

Similarly to the refactors to iothreads and vcpus, move the code that
initializes the emulator thread settings into single function.
---
 src/qemu/qemu_cgroup.c  | 66 -----------------------------------------
 src/qemu/qemu_cgroup.h  |  1 -
 src/qemu/qemu_process.c | 78 +++++++++++++++++++++++++++++++++++++++----------
 3 files changed, 62 insertions(+), 83 deletions(-)

diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c
index f3c5fbb..a294bb0 100644
--- a/src/qemu/qemu_cgroup.c
+++ b/src/qemu/qemu_cgroup.c
@@ -1062,72 +1062,6 @@ qemuSetupCgroupCpusetCpus(virCgroupPtr cgroup,


 int
-qemuSetupCgroupForEmulator(virDomainObjPtr vm)
-{
-    virBitmapPtr cpumask = NULL;
-    virCgroupPtr cgroup_emulator = NULL;
-    virDomainDefPtr def = vm->def;
-    qemuDomainObjPrivatePtr priv = vm->privateData;
-    unsigned long long period = vm->def->cputune.emulator_period;
-    long long quota = vm->def->cputune.emulator_quota;
-
-    if ((period || quota) &&
-        !virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPU)) {
-        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
-                       _("cgroup cpu is required for scheduler tuning"));
-        return -1;
-    }
-
-    /*
-     * If CPU cgroup controller is not initialized here, then we need
-     * neither period nor quota settings.  And if CPUSET controller is
-     * not initialized either, then there's nothing to do anyway.
-     */
-    if (!virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPU) &&
-        !virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPUSET))
-        return 0;
-
-    if (virCgroupNewThread(priv->cgroup, VIR_CGROUP_THREAD_EMULATOR, 0,
-                           true, &cgroup_emulator) < 0)
-        goto cleanup;
-
-    if (virCgroupMoveTask(priv->cgroup, cgroup_emulator) < 0)
-        goto cleanup;
-
-    if (def->cputune.emulatorpin)
-        cpumask = def->cputune.emulatorpin;
-    else if (def->placement_mode == VIR_DOMAIN_CPU_PLACEMENT_MODE_AUTO)
-        cpumask = priv->autoCpuset;
-    else if (def->cpumask)
-        cpumask = def->cpumask;
-
-    if (cpumask) {
-        if (virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPUSET) &&
-            qemuSetupCgroupCpusetCpus(cgroup_emulator, cpumask) < 0)
-            goto cleanup;
-    }
-
-    if (period || quota) {
-        if (virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPU) &&
-            qemuSetupCgroupVcpuBW(cgroup_emulator, period,
-                                  quota) < 0)
-            goto cleanup;
-    }
-
-    virCgroupFree(&cgroup_emulator);
-    return 0;
-
- cleanup:
-    if (cgroup_emulator) {
-        virCgroupRemove(cgroup_emulator);
-        virCgroupFree(&cgroup_emulator);
-    }
-
-    return -1;
-}
-
-
-int
 qemuRemoveCgroup(virDomainObjPtr vm)
 {
     qemuDomainObjPrivatePtr priv = vm->privateData;
diff --git a/src/qemu/qemu_cgroup.h b/src/qemu/qemu_cgroup.h
index a8b8e1b..7a9d10a 100644
--- a/src/qemu/qemu_cgroup.h
+++ b/src/qemu/qemu_cgroup.h
@@ -54,7 +54,6 @@ int qemuSetupCgroupVcpuBW(virCgroupPtr cgroup,
                           unsigned long long period,
                           long long quota);
 int qemuSetupCgroupCpusetCpus(virCgroupPtr cgroup, virBitmapPtr cpumask);
-int qemuSetupCgroupForEmulator(virDomainObjPtr vm);
 int qemuRemoveCgroup(virDomainObjPtr vm);

 #endif /* __QEMU_CGROUP_H__ */
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index e760182..07b7d63 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -2185,22 +2185,72 @@ qemuProcessSetLinkStates(virQEMUDriverPtr driver,
 }


-/* Set CPU affinities for emulator threads. */
 static int
-qemuProcessSetEmulatorAffinity(virDomainObjPtr vm)
+qemuProcessSetupEmulator(virDomainObjPtr vm)
 {
-    virBitmapPtr cpumask;
-    virDomainDefPtr def = vm->def;
+    virBitmapPtr cpumask = NULL;
+    virCgroupPtr cgroup_emulator = NULL;
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+    unsigned long long period = vm->def->cputune.emulator_period;
+    long long quota = vm->def->cputune.emulator_quota;
     int ret = -1;

-    if (def->cputune.emulatorpin)
-        cpumask = def->cputune.emulatorpin;
-    else if (def->cpumask)
-        cpumask = def->cpumask;
+    if ((period || quota) &&
+        !virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPU)) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("cgroup cpu is required for scheduler tuning"));
+        return -1;
+    }
+
+    if (vm->def->cputune.emulatorpin)
+        cpumask = vm->def->cputune.emulatorpin;
+    else if (vm->def->placement_mode == VIR_DOMAIN_CPU_PLACEMENT_MODE_AUTO &&
+             priv->autoCpuset)
+        cpumask = priv->autoCpuset;
     else
-        return 0;
+        cpumask = vm->def->cpumask;
+
+    /* If CPU cgroup controller is not initialized here, then we need
+     * neither period nor quota settings.  And if CPUSET controller is
+     * not initialized either, then there's nothing to do anyway. */
+    if (virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPU) ||
+        virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPUSET)) {
+
+        if (virCgroupNewThread(priv->cgroup, VIR_CGROUP_THREAD_EMULATOR, 0,
+                               true, &cgroup_emulator) < 0)
+            goto cleanup;
+
+        if (virCgroupMoveTask(priv->cgroup, cgroup_emulator) < 0)
+            goto cleanup;
+
+
+        if (cpumask) {
+            if (virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPUSET) &&
+                qemuSetupCgroupCpusetCpus(cgroup_emulator, cpumask) < 0)
+                goto cleanup;
+        }
+
+        if (period || quota) {
+            if (virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPU) &&
+                qemuSetupCgroupVcpuBW(cgroup_emulator, period,
+                                      quota) < 0)
+                goto cleanup;
+        }
+    }
+
+    if (cpumask &&
+        virProcessSetAffinity(vm->pid, cpumask) < 0)
+        goto cleanup;
+
+    ret = 0;
+
+ cleanup:
+    if (cgroup_emulator) {
+        if (ret < 0)
+            virCgroupRemove(cgroup_emulator);
+        virCgroupFree(&cgroup_emulator);
+    }

-    ret = virProcessSetAffinity(vm->pid, cpumask);
     return ret;
 }

@@ -5135,12 +5185,8 @@ qemuProcessLaunch(virConnectPtr conn,
     if (rv == -1) /* The VM failed to start */
         goto cleanup;

-    VIR_DEBUG("Setting cgroup for emulator (if required)");
-    if (qemuSetupCgroupForEmulator(vm) < 0)
-        goto cleanup;
-
-    VIR_DEBUG("Setting affinity of emulator threads");
-    if (qemuProcessSetEmulatorAffinity(vm) < 0)
+    VIR_DEBUG("Setting emulator tuning/settings");
+    if (qemuProcessSetupEmulator(vm) < 0)
         goto cleanup;

     VIR_DEBUG("Waiting for monitor to show up");
-- 
2.6.2