From 2ca32b4848a865fb088e8c00af0dc194701c373a Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 28 Jan 2011 16:05:32 -0800 Subject: [PATCH] [SCSI] fcoe: use dedicated workqueue instead of system_wq fcoe uses the system_wq to destroy ports and the work items need to be flushed before the driver is unloaded. As the work items free the containing data structure, they can't be flushed directly. The workqueue should be flushed instead. Also, the destruction works can be chained - ie. destruction of a port may lead to destruction of another port where the work item for the former queues the work for the latter. Currently, the depth of chain can be at most two and fcoe_exit() makes sure everything is complete by calling flush_scheduled_work() twice. With commit c8efcc25 (workqueue: allow chained queueing during destruction), destroy_workqueue() can take care of chained works on workqueue destruction. Add and use fcoe_wq instead. Simply destroying fcoe_wq on driver unload takes care of flushing. Signed-off-by: Tejun Heo Signed-off-by: Robert Love Signed-off-by: James Bottomley --- drivers/scsi/fcoe/fcoe.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-) diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c index 8a1005d117b7..46c57e5755ae 100644 --- a/drivers/scsi/fcoe/fcoe.c +++ b/drivers/scsi/fcoe/fcoe.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -58,6 +59,8 @@ MODULE_PARM_DESC(ddp_min, "Minimum I/O size in bytes for " \ DEFINE_MUTEX(fcoe_config_mutex); +static struct workqueue_struct *fcoe_wq; + /* fcoe_percpu_clean completion. Waiter protected by fcoe_create_mutex */ static DECLARE_COMPLETION(fcoe_flush_completion); @@ -1896,7 +1899,7 @@ static int fcoe_device_notification(struct notifier_block *notifier, list_del(&fcoe->list); port = lport_priv(fcoe->ctlr.lp); fcoe_interface_cleanup(fcoe); - schedule_work(&port->destroy_work); + queue_work(fcoe_wq, &port->destroy_work); goto out; break; case NETDEV_FEAT_CHANGE: @@ -2387,6 +2390,10 @@ static int __init fcoe_init(void) unsigned int cpu; int rc = 0; + fcoe_wq = alloc_workqueue("fcoe", 0, 0); + if (!fcoe_wq) + return -ENOMEM; + /* register as a fcoe transport */ rc = fcoe_transport_attach(&fcoe_sw_transport); if (rc) { @@ -2425,6 +2432,7 @@ out_free: fcoe_percpu_thread_destroy(cpu); } mutex_unlock(&fcoe_config_mutex); + destroy_workqueue(fcoe_wq); return rc; } module_init(fcoe_init); @@ -2450,7 +2458,7 @@ static void __exit fcoe_exit(void) list_del(&fcoe->list); port = lport_priv(fcoe->ctlr.lp); fcoe_interface_cleanup(fcoe); - schedule_work(&port->destroy_work); + queue_work(fcoe_wq, &port->destroy_work); } rtnl_unlock(); @@ -2461,15 +2469,17 @@ static void __exit fcoe_exit(void) mutex_unlock(&fcoe_config_mutex); - /* flush any asyncronous interface destroys, - * this should happen after the netdev notifier is unregistered */ - flush_scheduled_work(); - /* That will flush out all the N_Ports on the hostlist, but now we - * may have NPIV VN_Ports scheduled for destruction */ - flush_scheduled_work(); + /* + * destroy_work's may be chained but destroy_workqueue() + * can take care of them. Just kill the fcoe_wq. + */ + destroy_workqueue(fcoe_wq); - /* detach from scsi transport - * must happen after all destroys are done, therefor after the flush */ + /* + * Detaching from the scsi transport must happen after all + * destroys are done on the fcoe_wq. destroy_workqueue will + * enusre the fcoe_wq is flushed. + */ fcoe_if_exit(); /* detach from fcoe transport */ @@ -2618,7 +2628,7 @@ static int fcoe_vport_destroy(struct fc_vport *vport) mutex_lock(&n_port->lp_mutex); list_del(&vn_port->list); mutex_unlock(&n_port->lp_mutex); - schedule_work(&port->destroy_work); + queue_work(fcoe_wq, &port->destroy_work); return 0; } -- 2.39.2