kvmclock: run KVM_KVMCLOCK_CTRL ioctl in vcpu thread

According to KVM API Documentation, we should only
run vcpu ioctls from the same thread that was used
to create the vcpu. This patch makes KVM_KVMCLOCK_CTRL
ioctl consistent with the Documentation.

No functional change.
Signed-off-by: NYongji Xie <xieyongji@baidu.com>
Signed-off-by: NChai Wen <chaiwen@baidu.com>
Message-Id: <1531315364-2551-1-git-send-email-xieyongji@baidu.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NYongji Xie <elohimes@gmail.com>

hw/i386/kvm/clock.c

@@ -147,6 +147,15 @@ static void kvm_update_clock(KVMClockState *s)
     s->clock_is_reliable = kvm_has_adjust_clock_stable();
 }
 
+static void do_kvmclock_ctrl(CPUState *cpu, run_on_cpu_data data)
+{
+    int ret = kvm_vcpu_ioctl(cpu, KVM_KVMCLOCK_CTRL, 0);
+
+    if (ret && ret != -EINVAL) {
+        fprintf(stderr, "%s: %s\n", __func__, strerror(-ret));
+    }
+}
+
 static void kvmclock_vm_state_change(void *opaque, int running,
                                      RunState state)
 {
@@ -183,13 +192,7 @@ static void kvmclock_vm_state_change(void *opaque, int running,
             return;
         }
         CPU_FOREACH(cpu) {
-            ret = kvm_vcpu_ioctl(cpu, KVM_KVMCLOCK_CTRL, 0);
-            if (ret) {
-                if (ret != -EINVAL) {
-                    fprintf(stderr, "%s: %s\n", __func__, strerror(-ret));
-                }
-                return;
-            }
+            run_on_cpu(cpu, do_kvmclock_ctrl, RUN_ON_CPU_NULL);
         }
     } else {