kvm: Simplify cpu_synchronize_state()

cpu_synchronize_state() is a little unreadable since the 'modified'
argument isn't self-explanatory.  Simplify it by making it always
synchronize the kernel state into qemu, and automatically flush the
registers back to the kernel if they've been synchronized on this
exit.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/kvm-all.c b/kvm-all.c
index f669c3ac0f..15c30d41be 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -57,6 +57,7 @@ struct KVMState
     KVMSlot slots[32];
     int fd;
     int vmfd;
+    int regs_modified;
     int coalesced_mmio;
     int broken_set_mem_region;
     int migration_log;
@@ -576,6 +577,14 @@ static void kvm_run_coalesced_mmio(CPUState *env, struct kvm_run *run)
 #endif
 }
 
+void kvm_cpu_synchronize_state(CPUState *env)
+{
+    if (!env->kvm_state->regs_modified) {
+        kvm_arch_get_registers(env);
+        env->kvm_state->regs_modified = 1;
+    }
+}
+
 int kvm_cpu_exec(CPUState *env)
 {
     struct kvm_run *run = env->kvm_run;
@@ -590,6 +599,11 @@ int kvm_cpu_exec(CPUState *env)
             break;
         }
 
+        if (env->kvm_state->regs_modified) {
+            kvm_arch_put_registers(env);
+            env->kvm_state->regs_modified = 0;
+        }
+
         kvm_arch_pre_run(env, run);
         ret = kvm_vcpu_ioctl(env, KVM_RUN, 0);
         kvm_arch_post_run(env, run);