From db5b21a24e01d35495014076700efa02d6dcbb68 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Tue, 27 Nov 2018 15:51:59 -0800 Subject: [PATCH] scsi: target/core: Use system workqueues for TMF A quote from SAM-5: "The order in which task management requests are processed is not specified by the SCSI architecture model. The SCSI architecture model does not require in-order delivery of such task management requests or processing by the task manager in the order received. To guarantee the processing order of task management requests referencing sent to a specific logical unit, an application client should not have more than one such task management request pending to that logical unit." This means that it is safe to use the system workqueues instead of tmr_wq for processing TMFs. An intended side effect of this patch is that it enables concurrent processing of TMFs. Reviewed-by: Christoph Hellwig Cc: Nicholas Bellinger Cc: Mike Christie Cc: David Disseldorp Cc: Hannes Reinecke Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen --- drivers/target/target_core_device.c | 16 ---------------- drivers/target/target_core_transport.c | 2 +- include/target/target_core_base.h | 1 - 3 files changed, 1 insertion(+), 18 deletions(-) diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index 1d51df2b3e77..15805dec697b 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -986,18 +986,6 @@ int target_configure_device(struct se_device *dev) if (ret) goto out_destroy_device; - /* - * Startup the struct se_device processing thread - */ - dev->tmr_wq = alloc_workqueue("tmr-%s", WQ_MEM_RECLAIM | WQ_UNBOUND, 1, - dev->transport->name); - if (!dev->tmr_wq) { - pr_err("Unable to create tmr workqueue for %s\n", - dev->transport->name); - ret = -ENOMEM; - goto out_free_alua; - } - /* * Setup work_queue for QUEUE_FULL */ @@ -1026,8 +1014,6 @@ int target_configure_device(struct se_device *dev) return 0; -out_free_alua: - core_alua_free_lu_gp_mem(dev); out_destroy_device: dev->transport->destroy_device(dev); out_free_index: @@ -1046,8 +1032,6 @@ void target_free_device(struct se_device *dev) WARN_ON(!list_empty(&dev->dev_sep_list)); if (target_dev_configured(dev)) { - destroy_workqueue(dev->tmr_wq); - dev->transport->destroy_device(dev); mutex_lock(&device_mutex); diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index b0416978ab99..999178e7d9a5 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -3412,7 +3412,7 @@ int transport_generic_handle_tmr( } INIT_WORK(&cmd->work, target_tmr_work); - queue_work(cmd->se_dev->tmr_wq, &cmd->work); + schedule_work(&cmd->work); return 0; } EXPORT_SYMBOL(transport_generic_handle_tmr); diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 6e34ec4df6b7..9d827e49fcc6 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -796,7 +796,6 @@ struct se_device { struct t10_pr_registration *dev_pr_res_holder; struct list_head dev_sep_list; struct list_head dev_tmr_list; - struct workqueue_struct *tmr_wq; struct work_struct qf_work_queue; struct list_head delayed_cmd_list; struct list_head state_list;