scsi: lpfc: Add auto EQ delay logic

Administrator intervention is currently required to get good numbers
when switching from running latency tests to IOPS tests.

The configured interrupt coalescing values will greatly effect the
results of these tests.  Currently, the driver has a single coalescing
value set by values of the module attribute.  This patch changes the
driver to support auto-configuration of the coalescing value based on
the total number of outstanding IOs and average number of CQEs processed
per interrupt for an EQ.  Values are checked every 5 seconds.

The driver defaults to the automatic selection. Automatic selection can
be disabled by the new lpfc_auto_imax module_parameter.

Older hardware can only change interrupt coalescing by mailbox
command. Newer hardware supports change via a register. The patch
support both.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 30 insertions, 6 deletions

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index f60c9e3e37d7..040575adf9c6 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -13478,6 +13478,7 @@ process_cq:
 	/* Track the max number of CQEs processed in 1 EQ */
 	if (ecount > cq->CQ_max_cqe)
 		cq->CQ_max_cqe = ecount;
+	cq->assoc_qp->EQ_cqe_cnt += ecount;
 
 	/* Catch the no cq entry condition */
 	if (unlikely(ecount == 0))
@@ -13569,6 +13570,7 @@ lpfc_sli4_fof_handle_eqe(struct lpfc_hba *phba, struct lpfc_eqe *eqe)
 	/* Track the max number of CQEs processed in 1 EQ */
 	if (ecount > cq->CQ_max_cqe)
 		cq->CQ_max_cqe = ecount;
+	cq->assoc_qp->EQ_cqe_cnt += ecount;
 
 	/* Catch the no cq entry condition */
 	if (unlikely(ecount == 0))
@@ -13629,7 +13631,6 @@ lpfc_sli4_fof_intr_handler(int irq, void *dev_id)
 
 	/* Check device state for handling interrupt */
 	if (unlikely(lpfc_intr_state_check(phba))) {
-		eq->EQ_badstate++;
 		/* Check again for link_state with lock held */
 		spin_lock_irqsave(&phba->hbalock, iflag);
 		if (phba->link_state < LPFC_LINK_DOWN)
@@ -13741,7 +13742,6 @@ lpfc_sli4_hba_intr_handler(int irq, void *dev_id)
 
 	/* Check device state for handling interrupt */
 	if (unlikely(lpfc_intr_state_check(phba))) {
-		fpeq->EQ_badstate++;
 		/* Check again for link_state with lock held */
 		spin_lock_irqsave(&phba->hbalock, iflag);
 		if (phba->link_state < LPFC_LINK_DOWN)
@@ -14000,14 +14000,15 @@ lpfc_dual_chute_pci_bar_map(struct lpfc_hba *phba, uint16_t pci_barset)
  * fails this function will return -ENXIO.
  **/
 int
-lpfc_modify_hba_eq_delay(struct lpfc_hba *phba, uint32_t startq)
+lpfc_modify_hba_eq_delay(struct lpfc_hba *phba, uint32_t startq,
+			 uint32_t numq, uint32_t imax)
 {
 	struct lpfc_mbx_modify_eq_delay *eq_delay;
 	LPFC_MBOXQ_t *mbox;
 	struct lpfc_queue *eq;
 	int cnt, rc, length, status = 0;
 	uint32_t shdr_status, shdr_add_status;
-	uint32_t result;
+	uint32_t result, val;
 	int qidx;
 	union lpfc_sli4_cfg_shdr *shdr;
 	uint16_t dmult;
@@ -14026,22 +14027,45 @@ lpfc_modify_hba_eq_delay(struct lpfc_hba *phba, uint32_t startq)
 	eq_delay = &mbox->u.mqe.un.eq_delay;
 
 	/* Calculate delay multiper from maximum interrupt per second */
-	result = phba->cfg_fcp_imax / phba->io_channel_irqs;
+	result = imax / phba->io_channel_irqs;
 	if (result > LPFC_DMULT_CONST || result == 0)
 		dmult = 0;
 	else
 		dmult = LPFC_DMULT_CONST/result - 1;
+	if (dmult > LPFC_DMULT_MAX)
+		dmult = LPFC_DMULT_MAX;
 
 	cnt = 0;
 	for (qidx = startq; qidx < phba->io_channel_irqs; qidx++) {
 		eq = phba->sli4_hba.hba_eq[qidx];
 		if (!eq)
 			continue;
+		eq->q_mode = imax;
 		eq_delay->u.request.eq[cnt].eq_id = eq->queue_id;
 		eq_delay->u.request.eq[cnt].phase = 0;
 		eq_delay->u.request.eq[cnt].delay_multi = dmult;
 		cnt++;
-		if (cnt >= LPFC_MAX_EQ_DELAY_EQID_CNT)
+
+		/* q_mode is only used for auto_imax */
+		if (phba->sli.sli_flag & LPFC_SLI_USE_EQDR) {
+			/* Use EQ Delay Register method for q_mode */
+
+			/* Convert for EQ Delay register */
+			val =  phba->cfg_fcp_imax;
+			if (val) {
+				/* First, interrupts per sec per EQ */
+				val = phba->cfg_fcp_imax /
+					phba->io_channel_irqs;
+
+				/* us delay between each interrupt */
+				val = LPFC_SEC_TO_USEC / val;
+			}
+			eq->q_mode = val;
+		} else {
+			eq->q_mode = imax;
+		}
+
+		if (cnt >= numq)
 			break;
 	}
 	eq_delay->u.request.num_eq = cnt;