Piteball
/
android_kernel_samsung_msm8976
mirror of https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
1
1
Fork 0
Code Issues Projects Releases Wiki Activity

block: row: Don't notify URGENT if there are un-completed urgent req 

When ROW scheduler reports to the block layer that there is an urgent
request pending, the device driver may decide to stop the transmission
of the current request in order to handle the urgent one. If the current
transmitted request is an urgent request - we don't want it to be
stopped.
Due to the above ROW scheduler won't notify of an urgent request if
there are urgent requests in flight.

Change-Id: I2fa186d911b908ec7611682b378b9cdc48637ac7
Signed-off-by: Tatyana Brokhman <tlinder@codeaurora.org>
This commit is contained in:
Tatyana Brokhman 2013-01-24 15:08:40 +02:00 committed by Stephen Boyd
parent 279fe73dd9
commit 72ca8dabb7
1 changed files with 37 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
block/row-iosched.c
View File

@ -165,6 +165,8 @@ struct idling_data {
* @nr_reqs: nr_reqs[0] holds the number of all READ requests in
* scheduler, nr_reqs[1] holds the number of all WRITE
* requests in scheduler
* @nr_urgent_in_flight: number of uncompleted urgent requests
* (both reads and writes)
* @cycle_flags: used for marking unserved queueus
*
*/
@ -175,6 +177,7 @@ struct row_data {
struct idling_data rd_idle_data;
unsigned int nr_reqs[2];
unsigned int nr_urgent_in_flight;
unsigned int cycle_flags;
};
@ -303,6 +306,7 @@ static void row_add_request(struct request_queue *q,
row_log_rowq(rd, rqueue->prio,
"added urgent request (total on queue=%d)",
rqueue->nr_req);
rq->cmd_flags |= REQ_URGENT;
} else
row_log_rowq(rd, rqueue->prio,
"added request (total on queue=%d)", rqueue->nr_req);
@ -341,6 +345,20 @@ static int row_reinsert_req(struct request_queue *q,
return 0;
}
static void row_completed_req(struct request_queue *q, struct request *rq)
{
struct row_data *rd = q->elevator->elevator_data;
if (rq->cmd_flags & REQ_URGENT) {
if (!rd->nr_urgent_in_flight) {
pr_err("ROW BUG: %s() nr_urgent_in_flight = 0",
__func__);
return;
}
rd->nr_urgent_in_flight--;
}
}
/**
* row_urgent_pending() - Return TRUE if there is an urgent
* request on scheduler
@ -351,7 +369,20 @@ static bool row_urgent_pending(struct request_queue *q)
struct row_data *rd = q->elevator->elevator_data;
int i;
for (i = 0; i < ROWQ_MAX_PRIO; i++)
if (rd->nr_urgent_in_flight) {
row_log(rd->dispatch_queue, "%d urgent requests in flight",
rd->nr_urgent_in_flight);
return false;
}
for (i = ROWQ_HIGH_PRIO_IDX; i < ROWQ_REG_PRIO_IDX; i++)
if (!list_empty(&rd->row_queues[i].fifo)) {
row_log_rowq(rd, i,
"Urgent (high prio) request pending");
return true;
}
for (i = ROWQ_REG_PRIO_IDX; i < ROWQ_MAX_PRIO; i++)
if (row_queues_def[i].is_urgent && row_rowq_unserved(rd, i) &&
!list_empty(&rd->row_queues[i].fifo)) {
row_log_rowq(rd, i, "Urgent request pending");
@ -398,6 +429,8 @@ static void row_dispatch_insert(struct row_data *rd, int queue_idx)
row_clear_rowq_unserved(rd, queue_idx);
row_log_rowq(rd, queue_idx, " Dispatched request nr_disp = %d",
rd->row_queues[queue_idx].nr_dispatched);
if (rq->cmd_flags & REQ_URGENT)
rd->nr_urgent_in_flight++;
}
/*
@ -643,6 +676,7 @@ static int row_init_queue(struct request_queue *q)
rdata->dispatch_queue = q;
q->elevator->elevator_data = rdata;
rdata->nr_urgent_in_flight = 0;
rdata->nr_reqs[READ] = rdata->nr_reqs[WRITE] = 0;
return 0;
@ -709,6 +743,7 @@ static enum row_queue_prio row_get_queue_prio(struct request *rq)
rq->rq_disk->disk_name, __func__);
q_type = ROWQ_PRIO_REG_WRITE;
}
rq->cmd_flags |= REQ_URGENT;
break;
case IOPRIO_CLASS_IDLE:
if (data_dir == READ)
@ -866,6 +901,7 @@ static struct elevator_type iosched_row = {
.elevator_add_req_fn = row_add_request,
.elevator_reinsert_req_fn = row_reinsert_req,
.elevator_is_urgent_fn = row_urgent_pending,
.elevator_completed_req_fn = row_completed_req,
.elevator_former_req_fn = elv_rb_former_request,
.elevator_latter_req_fn = elv_rb_latter_request,
.elevator_set_req_fn = row_set_request,