KVM: s390: introduce kvm_s390_vcpu_{start,stop}

This patch introduces two new functions to set/clear the CPUSTAT_STOPPED bit and
makes use of it at all applicable places. These functions prepare the additional
execution of code when starting/stopping a vcpu.

The CPUSTAT_STOPPED bit should not be touched outside of these functions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

arch/s390/kvm/trace-s390.h

@@ -67,6 +67,27 @@ TRACE_EVENT(kvm_s390_destroy_vcpu,
 	    TP_printk("destroy cpu %d", __entry->id)
 	);
 
+/*
+ * Trace point for start and stop of vpcus.
+ */
+TRACE_EVENT(kvm_s390_vcpu_start_stop,
+	    TP_PROTO(unsigned int id, int state),
+	    TP_ARGS(id, state),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int, id)
+		    __field(int, state)
+		    ),
+
+	    TP_fast_assign(
+		    __entry->id = id;
+		    __entry->state = state;
+		    ),
+
+	    TP_printk("%s cpu %d", __entry->state ? "starting" : "stopping",
+		      __entry->id)
+	);
+
 /*
  * Trace points for injection of interrupts, either per machine or
  * per vcpu.