scsi: qla2xxx: Add support for ZIO6 interrupt threshold

Add sysfs support to control zio6 interrupt threshold. Using this sysfs hook
user can set when to generate interrupts. This value will be used to tell
firmware to generate interrupt at a certain interval.  If the number of
exchanges/commands fall below defined setting, then the interrupt will be
generated immediately by the firmware.

By default ZIO6 will coalesce interrupts to a specified interval
regardless of low traffic or high traffic.

[mkp: fixed several typos]

Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 33 insertions, 9 deletions

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index d0d5e332bafc..6fa321a4229d 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -2840,6 +2840,8 @@ qla2x00_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
 	atomic_set(&ha->num_pend_mbx_stage1, 0);
 	atomic_set(&ha->num_pend_mbx_stage2, 0);
 	atomic_set(&ha->num_pend_mbx_stage3, 0);
+	atomic_set(&ha->zio_threshold, DEFAULT_ZIO_THRESHOLD);
+	ha->last_zio_threshold = DEFAULT_ZIO_THRESHOLD;
 
 	/* Assign ISP specific operations. */
 	if (IS_QLA2100(ha)) {
@@ -6224,17 +6226,28 @@ intr_on_check:
 			mutex_unlock(&ha->mq_lock);
 		}
 
-		if (test_and_clear_bit(SET_ZIO_THRESHOLD_NEEDED, &base_vha->dpc_flags)) {
+		if (test_and_clear_bit(SET_NVME_ZIO_THRESHOLD_NEEDED,
+		    &base_vha->dpc_flags)) {
 			ql_log(ql_log_info, base_vha, 0xffffff,
 				"nvme: SET ZIO Activity exchange threshold to %d.\n",
 						ha->nvme_last_rptd_aen);
-			if (qla27xx_set_zio_threshold(base_vha, ha->nvme_last_rptd_aen)) {
+			if (qla27xx_set_zio_threshold(base_vha,
+			    ha->nvme_last_rptd_aen)) {
 				ql_log(ql_log_info, base_vha, 0xffffff,
-					"nvme: Unable to SET ZIO Activity exchange threshold to %d.\n",
-						ha->nvme_last_rptd_aen);
+				    "nvme: Unable to SET ZIO Activity exchange threshold to %d.\n",
+				    ha->nvme_last_rptd_aen);
 			}
 		}
 
+		if (test_and_clear_bit(SET_ZIO_THRESHOLD_NEEDED,
+		    &base_vha->dpc_flags)) {
+			ql_log(ql_log_info, base_vha, 0xffffff,
+			    "SET ZIO Activity exchange threshold to %d.\n",
+			    ha->last_zio_threshold);
+			qla27xx_set_zio_threshold(base_vha,
+			    ha->last_zio_threshold);
+		}
+
 		if (!IS_QLAFX00(ha))
 			qla2x00_do_dpc_all_vps(base_vha);
 
@@ -6447,13 +6460,24 @@ qla2x00_timer(struct timer_list *t)
 	 * FC-NVME
 	 * see if the active AEN count has changed from what was last reported.
 	 */
-	if (!vha->vp_idx &&
-		atomic_read(&ha->nvme_active_aen_cnt) != ha->nvme_last_rptd_aen &&
-		ha->zio_mode == QLA_ZIO_MODE_6) {
+	if (!vha->vp_idx && (atomic_read(&ha->nvme_active_aen_cnt) !=
+	    ha->nvme_last_rptd_aen) && ha->zio_mode == QLA_ZIO_MODE_6) {
 		ql_log(ql_log_info, vha, 0x3002,
-			"nvme: Sched: Set ZIO exchange threshold to %d.\n",
-			ha->nvme_last_rptd_aen);
+		    "nvme: Sched: Set ZIO exchange threshold to %d.\n",
+		    ha->nvme_last_rptd_aen);
 		ha->nvme_last_rptd_aen = atomic_read(&ha->nvme_active_aen_cnt);
+		set_bit(SET_NVME_ZIO_THRESHOLD_NEEDED, &vha->dpc_flags);
+		start_dpc++;
+	}
+
+	if (!vha->vp_idx &&
+	    (atomic_read(&ha->zio_threshold) != ha->last_zio_threshold) &&
+	    (ha->zio_mode == QLA_ZIO_MODE_6) &&
+	    (IS_QLA83XX(ha) || IS_QLA27XX(ha))) {
+		ql_log(ql_log_info, vha, 0x3002,
+		    "Sched: Set ZIO exchange threshold to %d.\n",
+		    ha->last_zio_threshold);
+		ha->last_zio_threshold = atomic_read(&ha->zio_threshold);
 		set_bit(SET_ZIO_THRESHOLD_NEEDED, &vha->dpc_flags);
 		start_dpc++;
 	}