s390x/kvm: propagate s390 cpu state to kvm

Let QEMU propagate the cpu state to kvm. If kvm doesn't yet support it, it is
silently ignored as kvm will still handle the cpu state itself in that case.

The state is not synced back, thus kvm won't have a chance to actively modify
the cpu state. To do so, control has to be given back to QEMU (which is already
done so in all relevant cases).

Setting of the cpu state can fail either because kvm doesn't support the
interface yet, or because the state is invalid/not supported. Failed attempts
will be traced

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
CC: Andreas Faerber <afaerber@suse.de>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

1 files changed, 41 insertions, 2 deletions

diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
index 415baea514..7c90b18631 100644
--- a/target-s390x/kvm.c
+++ b/target-s390x/kvm.c
@@ -181,9 +181,10 @@ unsigned long kvm_arch_vcpu_id(CPUState *cpu)
     return cpu->cpu_index;
 }
 
-int kvm_arch_init_vcpu(CPUState *cpu)
+int kvm_arch_init_vcpu(CPUState *cs)
 {
-    /* nothing todo yet */
+    S390CPU *cpu = S390_CPU(cs);
+    kvm_s390_set_cpu_state(cpu, cpu->env.cpu_state);
     return 0;
 }
 
@@ -1321,3 +1322,41 @@ int kvm_s390_get_memslot_count(KVMState *s)
 {
     return kvm_check_extension(s, KVM_CAP_NR_MEMSLOTS);
 }
+
+int kvm_s390_set_cpu_state(S390CPU *cpu, uint8_t cpu_state)
+{
+    struct kvm_mp_state mp_state = {};
+    int ret;
+
+    /* the kvm part might not have been initialized yet */
+    if (CPU(cpu)->kvm_state == NULL) {
+        return 0;
+    }
+
+    switch (cpu_state) {
+    case CPU_STATE_STOPPED:
+        mp_state.mp_state = KVM_MP_STATE_STOPPED;
+        break;
+    case CPU_STATE_CHECK_STOP:
+        mp_state.mp_state = KVM_MP_STATE_CHECK_STOP;
+        break;
+    case CPU_STATE_OPERATING:
+        mp_state.mp_state = KVM_MP_STATE_OPERATING;
+        break;
+    case CPU_STATE_LOAD:
+        mp_state.mp_state = KVM_MP_STATE_LOAD;
+        break;
+    default:
+        error_report("Requested CPU state is not a valid S390 CPU state: %u",
+                     cpu_state);
+        exit(1);
+    }
+
+    ret = kvm_vcpu_ioctl(CPU(cpu), KVM_SET_MP_STATE, &mp_state);
+    if (ret) {
+        trace_kvm_failed_cpu_state_set(CPU(cpu)->cpu_index, cpu_state,
+                                       strerror(-ret));
+    }
+
+    return ret;
+}