On 5/16/23 18:22, Damien Le Moal wrote:
On 5/17/23 07:33, Bart Van Assche wrote:
-/* Return the first request for which blk_rq_pos() >= pos. */
+/*
+ * Return the first request for which blk_rq_pos() >= @pos. For zoned devices,
+ * return the first request after the highest zone start <= @pos.
This comment is strange. What about:
For zoned devices, return the first request after the start of the zone
containing @pos.
I will make this change.
@@ -818,7 +835,20 @@ static void dd_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
* set expire time and add to fifo list
*/
rq->fifo_time = jiffies + dd->fifo_expire[data_dir];
- list_add_tail(&rq->queuelist, &per_prio->fifo_list[data_dir]);
+ insert_before = &per_prio->fifo_list[data_dir];
+#ifdef CONFIG_BLK_DEV_ZONED
+ /*
+ * Insert zoned writes such that requests are sorted by
+ * position per zone.
+ */
+ if (blk_rq_is_seq_zoned_write(rq)) {
+ struct request *rq2 = deadline_latter_request(rq);
+
+ if (rq2 && blk_rq_zone_no(rq2) == blk_rq_zone_no(rq))
+ insert_before = &rq2->queuelist;
+ }
+#endif
+ list_add_tail(&rq->queuelist, insert_before);
Why not:
insert_before = &per_prio->fifo_list[data_dir];
if (IS_ENABLED(CONFIG_BLK_DEV_ZONED)
&& blk_rq_is_seq_zoned_write(rq)) {
/*
* Insert zoned writes such that requests are sorted by
* position per zone.
*/
struct request *rq2 = deadline_latter_request(rq);
if (rq2 && blk_rq_zone_no(rq2) == blk_rq_zone_no(rq))
insert_before = &rq2->queuelist;
}
list_add_tail(&rq->queuelist, insert_before);
to avoid the ugly #ifdef ?
I think the above code won't build because no blk_rq_zone_no()
definition is available if CONFIG_BLK_DEV_ZONED=n. I prefer it this way
because my view is that using blk_rq_zone_no() if CONFIG_BLK_DEV_ZONED=n
is wrong.
Thanks,
Bart.
