[PATCH v2 12/15] lpfc: Cleanup entry_repost settings on SLI4 queues

[James Smart]

Too many work items being processed in IRQ context take a lot
of CPU time and cause problems.

With a recent change, we get out of the ISR after hitting entry_repost
work items on a queue. However, the actual values for entry repost are
still high. EQ is 128 and CQ is 128, this could translate into
processing 128 * 128 (16384) work items under IRQ context.

Set entry_repost in the actual queue creation routine now.
Limit EQ repost to 8 and CQ repost to 64 to further limit the amount
of time spent in the IRQ.

Fix fof IRQ routines as well.

Signed-off-by: Dick Kennedy <dick.kennedy at broadcom.com>
Signed-off-by: James Smart <james.smart at broadcom.com>

---
v2: portions of the original patch reworked:
 rq/mrq entry_repost values - moved to
     0004-lpfc-Fix-nvmet-RQ-resource-needs-for-large-block-wri.patch
 eq/cq processing breaks- moved to
     0006-lpfc-Fix-NMI-watchdog-assertions-when-running-nvmet-.patch

 drivers/scsi/lpfc/lpfc_sli.c  | 19 ++++++++-----------
 drivers/scsi/lpfc/lpfc_sli4.h |  6 ++++--
 2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 3fb4e715bfa2..903c06ff828a 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -13922,17 +13922,10 @@ lpfc_sli4_queue_alloc(struct lpfc_hba *phba, uint32_t entry_size,
 	}
 	queue->entry_size = entry_size;
 	queue->entry_count = entry_count;
-
-	/*
-	 * entry_repost is calculated based on the number of entries in the
-	 * queue. This works out except for RQs. If buffers are NOT initially
-	 * posted for every RQE, entry_repost should be adjusted accordingly.
-	 */
-	queue->entry_repost = (entry_count >> 3);
-	if (queue->entry_repost < LPFC_QUEUE_MIN_REPOST)
-		queue->entry_repost = LPFC_QUEUE_MIN_REPOST;
 	queue->phba = phba;
 
+	/* entry_repost will be set during q creation */
+
 	return queue;
 out_fail:
 	lpfc_sli4_queue_free(queue);
@@ -14163,6 +14156,7 @@ lpfc_eq_create(struct lpfc_hba *phba, struct lpfc_queue *eq, uint32_t imax)
 		status = -ENXIO;
 	eq->host_index = 0;
 	eq->hba_index = 0;
+	eq->entry_repost = LPFC_EQ_REPOST;
 
 	mempool_free(mbox, phba->mbox_mem_pool);
 	return status;
@@ -14236,9 +14230,9 @@ lpfc_cq_create(struct lpfc_hba *phba, struct lpfc_queue *cq,
 	default:
 		lpfc_printf_log(phba, KERN_ERR, LOG_SLI,
 				"0361 Unsupported CQ count: "
-				"entry cnt %d sz %d pg cnt %d repost %d\n",
+				"entry cnt %d sz %d pg cnt %d\n",
 				cq->entry_count, cq->entry_size,
-				cq->page_count, cq->entry_repost);
+				cq->page_count);
 		if (cq->entry_count < 256) {
 			status = -EINVAL;
 			goto out;
@@ -14291,6 +14285,7 @@ lpfc_cq_create(struct lpfc_hba *phba, struct lpfc_queue *cq,
 	cq->assoc_qid = eq->queue_id;
 	cq->host_index = 0;
 	cq->hba_index = 0;
+	cq->entry_repost = LPFC_CQ_REPOST;
 
 out:
 	mempool_free(mbox, phba->mbox_mem_pool);
@@ -14482,6 +14477,7 @@ lpfc_cq_create_set(struct lpfc_hba *phba, struct lpfc_queue **cqp,
 		cq->assoc_qid = eq->queue_id;
 		cq->host_index = 0;
 		cq->hba_index = 0;
+		cq->entry_repost = LPFC_CQ_REPOST;
 
 		rc = 0;
 		list_for_each_entry(dmabuf, &cq->page_list, list) {
@@ -14730,6 +14726,7 @@ lpfc_mq_create(struct lpfc_hba *phba, struct lpfc_queue *mq,
 	mq->subtype = subtype;
 	mq->host_index = 0;
 	mq->hba_index = 0;
+	mq->entry_repost = LPFC_MQ_REPOST;
 
 	/* link the mq onto the parent cq child list */
 	list_add_tail(&mq->list, &cq->child_list);
diff --git a/drivers/scsi/lpfc/lpfc_sli4.h b/drivers/scsi/lpfc/lpfc_sli4.h
index c1c9a9125266..cf863db27700 100644
--- a/drivers/scsi/lpfc/lpfc_sli4.h
+++ b/drivers/scsi/lpfc/lpfc_sli4.h
@@ -24,7 +24,6 @@
 #define LPFC_XRI_EXCH_BUSY_WAIT_TMO		10000
 #define LPFC_XRI_EXCH_BUSY_WAIT_T1   		10
 #define LPFC_XRI_EXCH_BUSY_WAIT_T2              30000
-#define LPFC_RELEASE_NOTIFICATION_INTERVAL	32
 #define LPFC_RPI_LOW_WATER_MARK			10
 
 #define LPFC_UNREG_FCF                          1
@@ -155,8 +154,11 @@ struct lpfc_queue {
 	uint32_t entry_count;	/* Number of entries to support on the queue */
 	uint32_t entry_size;	/* Size of each queue entry. */
 	uint32_t entry_repost;	/* Count of entries before doorbell is rung */
-#define LPFC_QUEUE_MIN_REPOST	8
+#define LPFC_EQ_REPOST		8
+#define LPFC_MQ_REPOST		8
+#define LPFC_CQ_REPOST		64
 #define LPFC_RQ_REPOST		64
+#define LPFC_RELEASE_NOTIFICATION_INTERVAL	32  /* For WQs */
 	uint32_t queue_id;	/* Queue ID assigned by the hardware */
 	uint32_t assoc_qid;     /* Queue ID associated with, for CQ/WQ/MQ */
 	uint32_t page_count;	/* Number of pages allocated for this queue */
-- 
2.11.0