add: TRACE(("return_free_message: returning msg %p\n", msg));
context: return_free_message(struct smp_msg *msg){//	dprintf("return_free_message: returning msg 0x%x\n", msg);	acquire_spinlock_nocheck(&free_msg_spinlock);	msg->next = free_msgs;	free_msgs = msg;	free_msg_count++;	release_spinlock(&free_msg_spinlock);}