[PATCH] mmc: queue: replace immediate with hsq->depth

[Wenchao Chen]

Hsq is similar to cqe, using hsq->depth to represent
the maximum processing capacity of hsq. We can adjust
hsq->depth according to the actual situation.

Signed-off-by: Wenchao Chen <wenchao.chen@xxxxxxxxxx>
---
 drivers/mmc/core/queue.c   | 6 +-----
 drivers/mmc/host/mmc_hsq.c | 1 +
 drivers/mmc/host/mmc_hsq.h | 7 +++++++
 include/linux/mmc/host.h   | 1 +
 4 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
index b396e3900717..a0a2412f62a7 100644
--- a/drivers/mmc/core/queue.c
+++ b/drivers/mmc/core/queue.c
@@ -260,11 +260,7 @@ static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
 		}
 		break;
 	case MMC_ISSUE_ASYNC:
-		/*
-		 * For MMC host software queue, we only allow 2 requests in
-		 * flight to avoid a long latency.
-		 */
-		if (host->hsq_enabled && mq->in_flight[issue_type] > 2) {
+		if (host->hsq_enabled && mq->in_flight[issue_type] > host->hsq_depth) {
 			spin_unlock_irq(&mq->lock);
 			return BLK_STS_RESOURCE;
 		}
diff --git a/drivers/mmc/host/mmc_hsq.c b/drivers/mmc/host/mmc_hsq.c
index 424dc7b07858..7b3952721c17 100644
--- a/drivers/mmc/host/mmc_hsq.c
+++ b/drivers/mmc/host/mmc_hsq.c
@@ -337,6 +337,7 @@ int mmc_hsq_init(struct mmc_hsq *hsq, struct mmc_host *mmc)
 	hsq->mmc = mmc;
 	hsq->mmc->cqe_private = hsq;
 	mmc->cqe_ops = &mmc_hsq_ops;
+	mmc->hsq_depth = HSQ_MAX_DEPTH;
 
 	for (i = 0; i < HSQ_NUM_SLOTS; i++)
 		hsq->tag_slot[i] = HSQ_INVALID_TAG;
diff --git a/drivers/mmc/host/mmc_hsq.h b/drivers/mmc/host/mmc_hsq.h
index 1808024fc6c5..795f6b9421d7 100644
--- a/drivers/mmc/host/mmc_hsq.h
+++ b/drivers/mmc/host/mmc_hsq.h
@@ -5,6 +5,13 @@
 #define HSQ_NUM_SLOTS	64
 #define HSQ_INVALID_TAG	HSQ_NUM_SLOTS
 
+/*
+ * For MMC host software queue, we usually allow 2 requests in
+ * flight to avoid a long latency. But we can adjust hsq->depth
+ * according to the actual situation.
+ */
+#define HSQ_MAX_DEPTH	2
+
 struct hsq_slot {
 	struct mmc_request *mrq;
 };
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 461d1543893b..1fd8b1dd8698 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -520,6 +520,7 @@ struct mmc_host {
 
 	/* Host Software Queue support */
 	bool			hsq_enabled;
+	int			hsq_depth;
 
 	u32			err_stats[MMC_ERR_MAX];
 	unsigned long		private[] ____cacheline_aligned;
-- 
2.17.1