linux-user: call rcu_(un)register_thread on pthread_(exit|create)

Signed-off-by: NEmilio G. Cota <cota@braap.org>
Message-Id: <1440375847-17603-13-git-send-email-cota@braap.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

linux-user/syscall.c

@@ -4513,6 +4513,7 @@ static void *clone_func(void *arg)
     CPUState *cpu;
     TaskState *ts;
 
+    rcu_register_thread();
     env = info->env;
     cpu = ENV_GET_CPU(env);
     thread_cpu = cpu;
@@ -5614,6 +5615,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             thread_cpu = NULL;
             object_unref(OBJECT(cpu));
             g_free(ts);
+            rcu_unregister_thread();
             pthread_exit(NULL);
         }
 #ifdef TARGET_GPROF