scsi: core: Register sysfs for SCSI workqueue

Permit scsi_wq_xxx and scsi_tmf_xxx to be bound to different CPUs to get
better isolation.

Use alloc_workqueue with WQ_SYSFS and drop __WQ_ORDERED_EXPLICIT since a
__WQ_ORDERED_EXPLICIT workqueue isn't allowed to change the CPU mask.

Link: https://lore.kernel.org/r/20200701030745.16897-2-bob.liu@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 7ec91c3..37d1c55 100644 (file)
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -272,8 +272,10 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
        if (shost->transportt->create_work_queue) {
                snprintf(shost->work_q_name, sizeof(shost->work_q_name),
                         "scsi_wq_%d", shost->host_no);
-               shost->work_q = create_singlethread_workqueue(
-                                       shost->work_q_name);
+               shost->work_q = alloc_workqueue("%s",
+                       WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND,
+                       1, shost->work_q_name);
+
                if (!shost->work_q) {
                        error = -EINVAL;
                        goto out_free_shost_data;
@@ -487,7 +489,7 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
        }
 
        shost->tmf_work_q = alloc_workqueue("scsi_tmf_%d",
-                                           WQ_UNBOUND | WQ_MEM_RECLAIM,
+                                       WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS,
                                           1, shost->host_no);
        if (!shost->tmf_work_q) {
                shost_printk(KERN_WARNING, shost,