예제 #1
0
static struct fiops_ioc *fiops_select_ioc(struct fiops_data *fiopsd)
{
	struct fiops_ioc *ioc;
	struct fiops_rb_root *service_tree = NULL;
	int i;
	struct request *rq;

	for (i = RT_WORKLOAD; i >= IDLE_WORKLOAD; i--) {
		if (!RB_EMPTY_ROOT(&fiopsd->service_tree[i].rb)) {
			service_tree = &fiopsd->service_tree[i];
			break;
		}
	}

	if (!service_tree)
		return NULL;

	ioc = fiops_rb_first(service_tree);

	rq = rq_entry_fifo(ioc->fifo.next);
	/*
	 * we are the only async task and sync requests are in flight, delay a
	 * moment. If there are other tasks coming, sync tasks have no chance
	 * to be starved, don't delay
	 */
	if (!rq_is_sync(rq) && fiopsd->in_flight[1] != 0 &&
			service_tree->count == 1) {
		fiops_log_ioc(fiopsd, ioc,
				"postpone async, in_flight async %d sync %d",
				fiopsd->in_flight[0], fiopsd->in_flight[1]);
		return NULL;
	}

	return ioc;
}
static void fiops_update_min_vios(struct fiops_rb_root *service_tree)
{
	struct fiops_ioc *ioc;

	ioc = fiops_rb_first(service_tree);
	if (!ioc)
		return;
	service_tree->min_vios = max_vios(service_tree->min_vios, ioc->vios);
}
static int fiops_forced_dispatch(struct fiops_data *fiopsd)
{
	struct fiops_ioc *ioc;
	int dispatched = 0;
	int i;

	for (i = RT_WORKLOAD; i >= IDLE_WORKLOAD; i--) {
		while (!RB_EMPTY_ROOT(&fiopsd->service_tree[i].rb)) {
			ioc = fiops_rb_first(&fiopsd->service_tree[i]);

			while (!list_empty(&ioc->fifo)) {
				fiops_dispatch_request(fiopsd, ioc);
				dispatched++;
			}
			if (fiops_ioc_on_rr(ioc))
				fiops_del_ioc_rr(fiopsd, ioc);
		}
	}
	return dispatched;
}