[SCSI] qla2xxx: Add CPU affinity support.
Set the module parameter ql2xmultique_tag to 1 to enable this
feature. In this mode, the total number of response queues
created is equal to the number of online cpus. Turning the block
layer's rq_affinity mode on enables requests to be routed to the
proper cpu and at the same time it enables completion of the IO
in a response queue that is affined to the cpu in the request
path.
Signed-off-by: Anirban Chakraborty <anirban.chakraborty@qlogic.com>
Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index e2647e0..d6817df 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -96,6 +96,13 @@
"Enables MQ settings "
"Default is 1 for single queue. Set it to number \
of queues in MQ mode.");
+
+int ql2xmultique_tag;
+module_param(ql2xmultique_tag, int, S_IRUGO|S_IRUSR);
+MODULE_PARM_DESC(ql2xmultique_tag,
+ "Enables CPU affinity settings for the driver "
+ "Default is 0 for no affinity of request and response IO. "
+ "Set it to 1 to turn on the cpu affinity.");
/*
* SCSI host template entry points
*/
@@ -256,6 +263,47 @@
ha->rsp_q_map = NULL;
}
+static int qla25xx_setup_mode(struct scsi_qla_host *vha)
+{
+ uint16_t options = 0;
+ int ques, req, ret;
+ struct qla_hw_data *ha = vha->hw;
+
+ if (ql2xmultique_tag) {
+ /* CPU affinity mode */
+ ha->wq = create_workqueue("qla2xxx_wq");
+ /* create a request queue for IO */
+ options |= BIT_7;
+ req = qla25xx_create_req_que(ha, options, 0, 0, -1,
+ QLA_DEFAULT_QUE_QOS);
+ if (!req) {
+ qla_printk(KERN_WARNING, ha,
+ "Can't create request queue\n");
+ goto fail;
+ }
+ vha->req = ha->req_q_map[req];
+ options |= BIT_1;
+ for (ques = 1; ques < ha->max_rsp_queues; ques++) {
+ ret = qla25xx_create_rsp_que(ha, options, 0, 0, req);
+ if (!ret) {
+ qla_printk(KERN_WARNING, ha,
+ "Response Queue create failed\n");
+ goto fail2;
+ }
+ }
+ DEBUG2(qla_printk(KERN_INFO, ha,
+ "CPU affinity mode enabled, no. of response"
+ " queues:%d, no. of request queues:%d\n",
+ ha->max_rsp_queues, ha->max_req_queues));
+ }
+ return 0;
+fail2:
+ qla25xx_delete_queues(vha);
+fail:
+ ha->mqenable = 0;
+ return 1;
+}
+
static char *
qla2x00_pci_info_str(struct scsi_qla_host *vha, char *str)
{
@@ -998,6 +1046,9 @@
if (qla2x00_vp_abort_isp(vha))
goto eh_host_reset_lock;
} else {
+ if (ha->wq)
+ flush_workqueue(ha->wq);
+
set_bit(ABORT_ISP_ACTIVE, &base_vha->dpc_flags);
if (qla2x00_abort_isp(base_vha)) {
clear_bit(ABORT_ISP_ACTIVE, &base_vha->dpc_flags);
@@ -1521,6 +1572,7 @@
{
resource_size_t pio;
uint16_t msix;
+ int cpus;
if (pci_request_selected_regions(ha->pdev, ha->bars,
QLA2XXX_DRIVER_NAME)) {
@@ -1575,7 +1627,7 @@
/* Determine queue resources */
ha->max_req_queues = ha->max_rsp_queues = 1;
- if (ql2xmaxqueues <= 1 &&
+ if ((ql2xmaxqueues <= 1 || ql2xmultique_tag < 1) &&
(!IS_QLA25XX(ha) && !IS_QLA81XX(ha)))
goto mqiobase_exit;
ha->mqiobase = ioremap(pci_resource_start(ha->pdev, 3),
@@ -1584,12 +1636,21 @@
/* Read MSIX vector size of the board */
pci_read_config_word(ha->pdev, QLA_PCI_MSIX_CONTROL, &msix);
ha->msix_count = msix;
- if (ql2xmaxqueues > 1) {
+ /* Max queues are bounded by available msix vectors */
+ /* queue 0 uses two msix vectors */
+ if (ql2xmultique_tag) {
+ cpus = num_online_cpus();
+ ha->max_rsp_queues = (ha->msix_count - 1 - cpus) ?
+ (cpus + 1) : (ha->msix_count - 1);
+ ha->max_req_queues = 2;
+ } else if (ql2xmaxqueues > 1) {
ha->max_req_queues = ql2xmaxqueues > QLA_MQ_SIZE ?
QLA_MQ_SIZE : ql2xmaxqueues;
DEBUG2(qla_printk(KERN_INFO, ha, "QoS mode set, max no"
" of request queues:%d\n", ha->max_req_queues));
}
+ qla_printk(KERN_INFO, ha,
+ "MSI-X vector count: %d\n", msix);
} else
qla_printk(KERN_INFO, ha, "BAR 3 not enabled\n");
@@ -1871,6 +1932,12 @@
goto probe_failed;
}
+ if (ha->mqenable)
+ if (qla25xx_setup_mode(base_vha))
+ qla_printk(KERN_WARNING, ha,
+ "Can't create queues, falling back to single"
+ " queue mode\n");
+
/*
* Startup the kernel thread for this host adapter
*/
@@ -1982,6 +2049,13 @@
base_vha->flags.online = 0;
+ /* Flush the work queue and remove it */
+ if (ha->wq) {
+ flush_workqueue(ha->wq);
+ destroy_workqueue(ha->wq);
+ ha->wq = NULL;
+ }
+
/* Kill the kernel thread for this host */
if (ha->dpc_thread) {
struct task_struct *t = ha->dpc_thread;