trace: Add event "guest_cpu_enter"

Signals the hot-plugging of a new virtual (guest) CPU.
Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Message-id: 147428971313.15111.18023030883528426840.stgit@fimbulvetr.bsc.es
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

trace-events

@@ -140,6 +140,14 @@ colo_filter_rewriter_conn_offset(uint32_t offset) ": offset=%u\n"
 
 ### Guest events, keep at bottom
 
+
+## vCPU
+
+# Hot-plug a new virtual (guest) CPU
+#
+# Targets: all
+vcpu guest_cpu_enter(void)
+
 # @vaddr: Access' virtual address.
 # @info : Access' information (see below).
 #

trace/control-target.c

@@ -9,6 +9,7 @@
 
 #include "qemu/osdep.h"
 #include "cpu.h"
+#include "trace.h"
 #include "trace/control.h"
 #include "translate-all.h"
 
@@ -117,4 +118,6 @@ void trace_init_vcpu(CPUState *vcpu)
             }
         }
     }
+
+    trace_guest_cpu_enter(vcpu);
 }