[PATCH 4/5] scsi: use block layer helpers to calculate num of queues

[Daniel Wagner <wagi@kernel.org>]

The calculation of the upper limit for queues does not depend solely on
the number of online CPUs; for example, the isolcpus kernel
command-line option must also be considered.

To account for this, the block layer provides a helper function to
retrieve the maximum number of queues. Use it to set an appropriate
upper queue number limit.

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Daniel Wagner <wagi@kernel.org>
---
 drivers/scsi/megaraid/megaraid_sas_base.c | 15 +++++++++------
 drivers/scsi/qla2xxx/qla_isr.c            | 10 +++++-----
 drivers/scsi/smartpqi/smartpqi_init.c     |  5 ++---
 3 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 3aac0e17cb00612ed7b6fb4a2e8745c7120fc506..0224eb97092bd938250f108522daaf9f033c1a4d 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -5967,7 +5967,8 @@ megasas_alloc_irq_vectors(struct megasas_instance *instance)
 		else
 			instance->iopoll_q_count = 0;
 
-		num_msix_req = num_online_cpus() + instance->low_latency_index_start;
+		num_msix_req = blk_mq_num_online_queues(0) +
+			instance->low_latency_index_start;
 		instance->msix_vectors = min(num_msix_req,
 				instance->msix_vectors);
 
@@ -5983,7 +5984,8 @@ megasas_alloc_irq_vectors(struct megasas_instance *instance)
 		/* Disable Balanced IOPS mode and try realloc vectors */
 		instance->perf_mode = MR_LATENCY_PERF_MODE;
 		instance->low_latency_index_start = 1;
-		num_msix_req = num_online_cpus() + instance->low_latency_index_start;
+		num_msix_req = blk_mq_num_online_queues(0) +
+			instance->low_latency_index_start;
 
 		instance->msix_vectors = min(num_msix_req,
 				instance->msix_vectors);
@@ -6239,7 +6241,7 @@ static int megasas_init_fw(struct megasas_instance *instance)
 		intr_coalescing = (scratch_pad_1 & MR_INTR_COALESCING_SUPPORT_OFFSET) ?
 								true : false;
 		if (intr_coalescing &&
-			(num_online_cpus() >= MR_HIGH_IOPS_QUEUE_COUNT) &&
+			(blk_mq_num_online_queues(0) >= MR_HIGH_IOPS_QUEUE_COUNT) &&
 			(instance->msix_vectors == MEGASAS_MAX_MSIX_QUEUES))
 			instance->perf_mode = MR_BALANCED_PERF_MODE;
 		else
@@ -6283,7 +6285,8 @@ static int megasas_init_fw(struct megasas_instance *instance)
 		else
 			instance->low_latency_index_start = 1;
 
-		num_msix_req = num_online_cpus() + instance->low_latency_index_start;
+		num_msix_req = blk_mq_num_online_queues(0) +
+			instance->low_latency_index_start;
 
 		instance->msix_vectors = min(num_msix_req,
 				instance->msix_vectors);
@@ -6315,8 +6318,8 @@ static int megasas_init_fw(struct megasas_instance *instance)
 	megasas_setup_reply_map(instance);
 
 	dev_info(&instance->pdev->dev,
-		"current msix/online cpus\t: (%d/%d)\n",
-		instance->msix_vectors, (unsigned int)num_online_cpus());
+		"current msix/max num queues\t: (%d/%u)\n",
+		instance->msix_vectors, blk_mq_num_online_queues(0));
 	dev_info(&instance->pdev->dev,
 		"RDPQ mode\t: (%s)\n", instance->is_rdpq ? "enabled" : "disabled");
 
diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index fe98c76e9be32ff03a1960f366f0d700d1168383..c4c6b5c6658c0734f7ff68bcc31b33dde87296dd 100644
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -4533,13 +4533,13 @@ qla24xx_enable_msix(struct qla_hw_data *ha, struct rsp_que *rsp)
 	if (USER_CTRL_IRQ(ha) || !ha->mqiobase) {
 		/* user wants to control IRQ setting for target mode */
 		ret = pci_alloc_irq_vectors(ha->pdev, min_vecs,
-		    min((u16)ha->msix_count, (u16)(num_online_cpus() + min_vecs)),
-		    PCI_IRQ_MSIX);
+			blk_mq_num_online_queues(ha->msix_count) + min_vecs,
+			PCI_IRQ_MSIX);
 	} else
 		ret = pci_alloc_irq_vectors_affinity(ha->pdev, min_vecs,
-		    min((u16)ha->msix_count, (u16)(num_online_cpus() + min_vecs)),
-		    PCI_IRQ_MSIX | PCI_IRQ_AFFINITY,
-		    &desc);
+			blk_mq_num_online_queues(ha->msix_count) + min_vecs,
+			PCI_IRQ_MSIX | PCI_IRQ_AFFINITY,
+			&desc);
 
 	if (ret < 0) {
 		ql_log(ql_log_fatal, vha, 0x00c7,
diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index 3d40a63e378d792ffc005c51cb2fdbb04e1acc5f..125944941601e683e9aa9d4fc6a346230bef904b 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -5294,15 +5294,14 @@ static void pqi_calculate_queue_resources(struct pqi_ctrl_info *ctrl_info)
 	if (is_kdump_kernel()) {
 		num_queue_groups = 1;
 	} else {
-		int num_cpus;
 		int max_queue_groups;
 
 		max_queue_groups = min(ctrl_info->max_inbound_queues / 2,
 			ctrl_info->max_outbound_queues - 1);
 		max_queue_groups = min(max_queue_groups, PQI_MAX_QUEUE_GROUPS);
 
-		num_cpus = num_online_cpus();
-		num_queue_groups = min(num_cpus, ctrl_info->max_msix_vectors);
+		num_queue_groups =
+			blk_mq_num_online_queues(ctrl_info->max_msix_vectors);
 		num_queue_groups = min(num_queue_groups, max_queue_groups);
 	}
 

-- 
2.49.0