trace: Trace vm_start()/vm_stop()

VM state change notifications are invoked from vm_start()/vm_stop().
Trace these state changes so we can reason about the state of the VM
from trace output.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

trace-events

@@ -189,3 +189,6 @@ disable sun4m_iommu_mem_writel_pgflush(uint32_t val) "page flush %x"
 disable sun4m_iommu_page_get_flags(uint64_t pa, uint64_t iopte, uint32_t ret) "get flags addr %"PRIx64" => pte %"PRIx64", *pte = %x"
 disable sun4m_iommu_translate_pa(uint64_t addr, uint64_t pa, uint32_t iopte) "xlate dva %"PRIx64" => pa %"PRIx64" iopte = %x"
 disable sun4m_iommu_bad_addr(uint64_t addr) "bad addr %"PRIx64""
+
+# vl.c
+disable vm_state_notify(int running, int reason) "running %d reason %d"

vl.c

@@ -158,6 +158,7 @@ int main(int argc, char **argv)
 
 #include "slirp/libslirp.h"
 
+#include "trace.h"
 #include "qemu-queue.h"
 #include "cpus.h"
 #include "arch_init.h"
@@ -1074,6 +1075,8 @@ void vm_state_notify(int running, int reason)
 {
     VMChangeStateEntry *e;
 
+    trace_vm_state_notify(running, reason);
+
     for (e = vm_change_state_head.lh_first; e; e = e->entries.le_next) {
         e->cb(e->opaque, running, reason);
     }