}
EXPORT_SYMBOL_GPL(blk_mq_sched_try_insert_merge);
-static bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx,
- struct request *rq)
-{
- /*
- * dispatch flush and passthrough rq directly
- *
- * passthrough request has to be added to hctx->dispatch directly.
- * For some reason, device may be in one situation which can't
- * handle FS request, so STS_RESOURCE is always returned and the
- * FS request will be added to hctx->dispatch. However passthrough
- * request may be required at that time for fixing the problem. If
- * passthrough request is added to scheduler queue, there isn't any
- * chance to dispatch it given we prioritize requests in hctx->dispatch.
- */
- if ((rq->rq_flags & RQF_FLUSH_SEQ) || blk_rq_is_passthrough(rq))
- return true;
-
- return false;
-}
-
-void blk_mq_sched_insert_request(struct request *rq, bool at_head,
- bool run_queue, bool async)
-{
- struct request_queue *q = rq->q;
- struct elevator_queue *e = q->elevator;
- struct blk_mq_ctx *ctx = rq->mq_ctx;
- struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
-
- WARN_ON(e && (rq->tag != BLK_MQ_NO_TAG));
-
- if (blk_mq_sched_bypass_insert(hctx, rq)) {
- /*
- * Firstly normal IO request is inserted to scheduler queue or
- * sw queue, meantime we add flush request to dispatch queue(
- * hctx->dispatch) directly and there is at most one in-flight
- * flush request for each hw queue, so it doesn't matter to add
- * flush request to tail or front of the dispatch queue.
- *
- * Secondly in case of NCQ, flush request belongs to non-NCQ
- * command, and queueing it will fail when there is any
- * in-flight normal IO request(NCQ command). When adding flush
- * rq to the front of hctx->dispatch, it is easier to introduce
- * extra time to flush rq's latency because of S_SCHED_RESTART
- * compared with adding to the tail of dispatch queue, then
- * chance of flush merge is increased, and less flush requests
- * will be issued to controller. It is observed that ~10% time
- * is saved in blktests block/004 on disk attached to AHCI/NCQ
- * drive when adding flush rq to the front of hctx->dispatch.
- *
- * Simply queue flush rq to the front of hctx->dispatch so that
- * intensive flush workloads can benefit in case of NCQ HW.
- */
- at_head = (rq->rq_flags & RQF_FLUSH_SEQ) ? true : at_head;
- blk_mq_request_bypass_insert(rq, at_head, false);
- goto run;
- }
-
- if (e) {
- LIST_HEAD(list);
-
- list_add(&rq->queuelist, &list);
- e->type->ops.insert_requests(hctx, &list, at_head);
- } else {
- spin_lock(&ctx->lock);
- __blk_mq_insert_request(hctx, rq, at_head);
- spin_unlock(&ctx->lock);
- }
-
-run:
- if (run_queue)
- blk_mq_run_hw_queue(hctx, async);
-}
-
static int blk_mq_sched_alloc_map_and_rqs(struct request_queue *q,
struct blk_mq_hw_ctx *hctx,
unsigned int hctx_idx)
static DEFINE_PER_CPU(struct llist_head, blk_cpu_done);
+static void blk_mq_insert_request(struct request *rq, bool at_head,
+ bool run_queue, bool async);
static void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
struct list_head *list);
if (current->plug && !at_head)
blk_add_rq_to_plug(current->plug, rq);
else
- blk_mq_sched_insert_request(rq, at_head, true, false);
+ blk_mq_insert_request(rq, at_head, true, false);
}
EXPORT_SYMBOL_GPL(blk_execute_rq_nowait);
rq->end_io = blk_end_sync_rq;
blk_account_io_start(rq);
- blk_mq_sched_insert_request(rq, at_head, true, false);
+ blk_mq_insert_request(rq, at_head, true, false);
if (blk_rq_is_poll(rq)) {
blk_rq_poll_completion(rq, &wait.done);
if (rq->rq_flags & RQF_DONTPREP)
blk_mq_request_bypass_insert(rq, false, false);
else
- blk_mq_sched_insert_request(rq, true, false, false);
+ blk_mq_insert_request(rq, true, false, false);
}
while (!list_empty(&rq_list)) {
rq = list_entry(rq_list.next, struct request, queuelist);
list_del_init(&rq->queuelist);
- blk_mq_sched_insert_request(rq, false, false, false);
+ blk_mq_insert_request(rq, false, false, false);
}
blk_mq_run_hw_queues(q, false);
blk_mq_run_hw_queue(hctx, run_queue_async);
}
+static bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx,
+ struct request *rq)
+{
+ /*
+ * dispatch flush and passthrough rq directly
+ *
+ * passthrough request has to be added to hctx->dispatch directly.
+ * For some reason, device may be in one situation which can't
+ * handle FS request, so STS_RESOURCE is always returned and the
+ * FS request will be added to hctx->dispatch. However passthrough
+ * request may be required at that time for fixing the problem. If
+ * passthrough request is added to scheduler queue, there isn't any
+ * chance to dispatch it given we prioritize requests in hctx->dispatch.
+ */
+ if ((rq->rq_flags & RQF_FLUSH_SEQ) || blk_rq_is_passthrough(rq))
+ return true;
+
+ return false;
+}
+
+static void blk_mq_insert_request(struct request *rq, bool at_head,
+ bool run_queue, bool async)
+{
+ struct request_queue *q = rq->q;
+ struct elevator_queue *e = q->elevator;
+ struct blk_mq_ctx *ctx = rq->mq_ctx;
+ struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
+
+ WARN_ON(e && (rq->tag != BLK_MQ_NO_TAG));
+
+ if (blk_mq_sched_bypass_insert(hctx, rq)) {
+ /*
+ * Firstly normal IO request is inserted to scheduler queue or
+ * sw queue, meantime we add flush request to dispatch queue(
+ * hctx->dispatch) directly and there is at most one in-flight
+ * flush request for each hw queue, so it doesn't matter to add
+ * flush request to tail or front of the dispatch queue.
+ *
+ * Secondly in case of NCQ, flush request belongs to non-NCQ
+ * command, and queueing it will fail when there is any
+ * in-flight normal IO request(NCQ command). When adding flush
+ * rq to the front of hctx->dispatch, it is easier to introduce
+ * extra time to flush rq's latency because of S_SCHED_RESTART
+ * compared with adding to the tail of dispatch queue, then
+ * chance of flush merge is increased, and less flush requests
+ * will be issued to controller. It is observed that ~10% time
+ * is saved in blktests block/004 on disk attached to AHCI/NCQ
+ * drive when adding flush rq to the front of hctx->dispatch.
+ *
+ * Simply queue flush rq to the front of hctx->dispatch so that
+ * intensive flush workloads can benefit in case of NCQ HW.
+ */
+ at_head = (rq->rq_flags & RQF_FLUSH_SEQ) ? true : at_head;
+ blk_mq_request_bypass_insert(rq, at_head, false);
+ goto run;
+ }
+
+ if (e) {
+ LIST_HEAD(list);
+
+ list_add(&rq->queuelist, &list);
+ e->type->ops.insert_requests(hctx, &list, at_head);
+ } else {
+ spin_lock(&ctx->lock);
+ __blk_mq_insert_request(hctx, rq, at_head);
+ spin_unlock(&ctx->lock);
+ }
+
+run:
+ if (run_queue)
+ blk_mq_run_hw_queue(hctx, async);
+}
+
static void blk_mq_bio_to_request(struct request *rq, struct bio *bio,
unsigned int nr_segs)
{
if (bypass_insert)
return BLK_STS_RESOURCE;
- blk_mq_sched_insert_request(rq, false, run_queue, false);
+ blk_mq_insert_request(rq, false, run_queue, false);
return BLK_STS_OK;
}
else if ((rq->rq_flags & RQF_ELV) ||
(rq->mq_hctx->dispatch_busy &&
(q->nr_hw_queues == 1 || !is_sync)))
- blk_mq_sched_insert_request(rq, false, true, true);
+ blk_mq_insert_request(rq, false, true, true);
else
blk_mq_run_dispatch_ops(rq->q,
blk_mq_try_issue_directly(rq->mq_hctx, rq));
projects / linux-block.git / commitdiff