/*
* row_dispatch_requests() - selects the next request to dispatch
* @q: requests queue
* @force: flag indicating if forced dispatch
*
* Return 0 if no requests were moved to the dispatch queue.
* 1 otherwise
*
*/
static int row_dispatch_requests(struct request_queue *q, int force)
{
struct row_data *rd = (struct row_data *)q->elevator->elevator_data;
int ret = 0, currq, ioprio_class_to_serve, start_idx, end_idx;
if (force && hrtimer_active(&rd->rd_idle_data.hr_timer)) {
if (hrtimer_try_to_cancel(&rd->rd_idle_data.hr_timer) >= 0) {
row_log(rd->dispatch_queue,
"Canceled delayed work on %d - forced dispatch",
rd->rd_idle_data.idling_queue_idx);
rd->rd_idle_data.idling_queue_idx = ROWQ_MAX_PRIO;
}
}
if (rd->pending_urgent_rq) {
row_log(rd->dispatch_queue, "dispatching urgent request");
row_dispatch_insert(rd, rd->pending_urgent_rq);
ret = 1;
goto done;
}
ioprio_class_to_serve = row_get_ioprio_class_to_serve(rd, force);
row_log(rd->dispatch_queue, "Dispatching from %d priority class",
ioprio_class_to_serve);
switch (ioprio_class_to_serve) {
case IOPRIO_CLASS_NONE:
rd->last_served_ioprio_class = IOPRIO_CLASS_NONE;
goto done;
case IOPRIO_CLASS_RT:
start_idx = ROWQ_HIGH_PRIO_IDX;
end_idx = ROWQ_REG_PRIO_IDX;
break;
case IOPRIO_CLASS_BE:
start_idx = ROWQ_REG_PRIO_IDX;
end_idx = ROWQ_LOW_PRIO_IDX;
break;
case IOPRIO_CLASS_IDLE:
start_idx = ROWQ_LOW_PRIO_IDX;
end_idx = ROWQ_MAX_PRIO;
break;
default:
pr_err("%s(): Invalid I/O priority class", __func__);
goto done;
}
currq = row_get_next_queue(q, rd, start_idx, end_idx);
/* Dispatch */
if (currq >= 0) {
row_dispatch_insert(rd,
rq_entry_fifo(rd->row_queues[currq].fifo.next));
ret = 1;
}
done:
return ret;
}
/*
* row_dispatch_requests() - selects the next request to dispatch
* @q: requests queue
* @force: ignored
*
* Return 0 if no requests were moved to the dispatch queue.
* 1 otherwise
*
*/
static int row_dispatch_requests(struct request_queue *q, int force)
{
struct row_data *rd = (struct row_data *)q->elevator->elevator_data;
int ret = 0, currq, i;
currq = rd->curr_queue;
/*
* Find the first unserved queue (with higher priority then currq)
* that is not empty
*/
for (i = 0; i < currq; i++) {
if (row_rowq_unserved(rd, i) &&
!list_empty(&rd->row_queues[i].rqueue.fifo)) {
row_log_rowq(rd, currq,
" Preemting for unserved rowq%d", i);
rd->curr_queue = i;
row_dispatch_insert(rd);
ret = 1;
goto done;
}
}
if (rd->row_queues[currq].rqueue.nr_dispatched >=
rd->row_queues[currq].disp_quantum) {
rd->row_queues[currq].rqueue.nr_dispatched = 0;
row_log_rowq(rd, currq, "Expiring rqueue");
ret = row_choose_queue(rd);
if (ret)
row_dispatch_insert(rd);
goto done;
}
/* Dispatch from curr_queue */
if (list_empty(&rd->row_queues[currq].rqueue.fifo)) {
/* check idling */
if (delayed_work_pending(&rd->read_idle.idle_work)) {
row_log_rowq(rd, currq,
"Delayed work pending. Exiting");
goto done;
}
if (queue_idling_enabled[currq] &&
rd->row_queues[currq].rqueue.idle_data.begin_idling) {
if (!kblockd_schedule_delayed_work(rd->dispatch_queue,
&rd->read_idle.idle_work, jiffies +
msecs_to_jiffies(rd->read_idle.idle_time))) {
row_log_rowq(rd, currq,
"Work already on queue!");
pr_err("ROW_BUG: Work already on queue!");
} else
row_log_rowq(rd, currq,
"Scheduled delayed work. exiting");
goto done;
} else {
row_log_rowq(rd, currq,
"Currq empty. Choose next queue");
ret = row_choose_queue(rd);
if (!ret)
goto done;
}
}
ret = 1;
row_dispatch_insert(rd);
done:
return ret;
}
/*
* row_dispatch_requests() - selects the next request to dispatch
* @q: requests queue
* @force: ignored
*
* Return 0 if no requests were moved to the dispatch queue.
* 1 otherwise
*
*/
static int row_dispatch_requests(struct request_queue *q, int force)
{
struct row_data *rd = (struct row_data *)q->elevator->elevator_data;
int ret = 0, currq, i;
currq = rd->curr_queue;
/*
* Find the first unserved queue (with higher priority then currq)
* that is not empty
*/
for (i = 0; i < currq; i++) {
if (row_rowq_unserved(rd, i) &&
!list_empty(&rd->row_queues[i].rqueue.fifo)) {
rd->curr_queue = i;
row_dispatch_insert(rd);
ret = 1;
goto done;
}
}
if (rd->row_queues[currq].rqueue.nr_dispatched >=
rd->row_queues[currq].disp_quantum) {
rd->row_queues[currq].rqueue.nr_dispatched = 0;
ret = row_choose_queue(rd);
if (ret)
row_dispatch_insert(rd);
goto done;
}
/* Dispatch from curr_queue */
if (list_empty(&rd->row_queues[currq].rqueue.fifo)) {
/* check idling */
if (delayed_work_pending(&rd->read_idle.idle_work)) {
if (force) {
(void)cancel_delayed_work(
&rd->read_idle.idle_work);
} else {
goto done;
}
}
if (!force && queue_idling_enabled[currq] &&
rd->row_queues[currq].rqueue.idle_data.begin_idling) {
if (!queue_delayed_work(rd->read_idle.idle_workqueue,
&rd->read_idle.idle_work,
rd->read_idle.idle_time)) {
} else
goto done;
} else {
ret = row_choose_queue(rd);
if (!ret)
goto done;
}
}
ret = 1;
row_dispatch_insert(rd);
done:
return ret;
}
