From: Christof Schmitt Date: Mon, 2 Mar 2009 12:09:01 +0000 (+0100) Subject: [SCSI] zfcp: Send ELS ADISC from workqueue X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=8fdf30d5429605a4c30cc515c73e5eab140035de;p=linux-beck.git [SCSI] zfcp: Send ELS ADISC from workqueue Issue ELS ADISC requests from workqueue. This allows the link test request to be sent when the request queue is full due to I/O load for other remote ports. It also simplifies request queue locking, zfcp_fsf_send_fcp_command_task is now the only function that has interrupts disabled from the caller. This is also a prereq for the FC passthrough support that issues ELS requests from userspace. Acked-by: Swen Schillig Signed-off-by: Christof Schmitt Signed-off-by: James Bottomley --- diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c index 969a3f093037..1e16ab58b242 100644 --- a/drivers/s390/scsi/zfcp_aux.c +++ b/drivers/s390/scsi/zfcp_aux.c @@ -604,6 +604,7 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn, init_waitqueue_head(&port->remove_wq); INIT_LIST_HEAD(&port->unit_list_head); INIT_WORK(&port->gid_pn_work, zfcp_erp_port_strategy_open_lookup); + INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work); port->adapter = adapter; port->d_id = d_id; diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h index ff15f11923e9..8412bb992ea1 100644 --- a/drivers/s390/scsi/zfcp_def.h +++ b/drivers/s390/scsi/zfcp_def.h @@ -513,6 +513,7 @@ struct zfcp_port { u32 maxframe_size; u32 supported_classes; struct work_struct gid_pn_work; + struct work_struct test_link_work; }; struct zfcp_unit { diff --git a/drivers/s390/scsi/zfcp_ext.h b/drivers/s390/scsi/zfcp_ext.h index 799ce1db1f56..a2b4987ac652 100644 --- a/drivers/s390/scsi/zfcp_ext.h +++ b/drivers/s390/scsi/zfcp_ext.h @@ -101,6 +101,7 @@ extern void zfcp_fc_incoming_els(struct zfcp_fsf_req *); extern int zfcp_fc_ns_gid_pn(struct zfcp_erp_action *); extern void zfcp_fc_plogi_evaluate(struct zfcp_port *, struct fsf_plogi *); extern void zfcp_test_link(struct zfcp_port *); +extern void zfcp_fc_link_test_work(struct work_struct *); extern void zfcp_fc_nameserver_init(struct zfcp_adapter *); /* zfcp_fsf.c */ diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index 67e6b7177870..0f435ed9d1a0 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -421,19 +421,12 @@ static int zfcp_fc_adisc(struct zfcp_port *port) return zfcp_fsf_send_els(&adisc->els); } -/** - * zfcp_test_link - lightweight link test procedure - * @port: port to be tested - * - * Test status of a link to a remote port using the ELS command ADISC. - * If there is a problem with the remote port, error recovery steps - * will be triggered. - */ -void zfcp_test_link(struct zfcp_port *port) +void zfcp_fc_link_test_work(struct work_struct *work) { + struct zfcp_port *port = + container_of(work, struct zfcp_port, test_link_work); int retval; - zfcp_port_get(port); retval = zfcp_fc_adisc(port); if (retval == 0) return; @@ -444,6 +437,21 @@ void zfcp_test_link(struct zfcp_port *port) zfcp_erp_port_forced_reopen(port, 0, 65, NULL); } +/** + * zfcp_test_link - lightweight link test procedure + * @port: port to be tested + * + * Test status of a link to a remote port using the ELS command ADISC. + * If there is a problem with the remote port, error recovery steps + * will be triggered. + */ +void zfcp_test_link(struct zfcp_port *port) +{ + zfcp_port_get(port); + if (!queue_work(zfcp_data.work_queue, &port->test_link_work)) + zfcp_port_put(port); +} + static void zfcp_free_sg_env(struct zfcp_gpn_ft *gpn_ft, int buf_num) { struct scatterlist *sg = &gpn_ft->sg_req; diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c index cc69db3b71e7..9c3f91a343f3 100644 --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -647,14 +647,6 @@ static void zfcp_fsf_exchange_port_data_handler(struct zfcp_fsf_req *req) } } -static int zfcp_fsf_sbal_available(struct zfcp_adapter *adapter) -{ - if (atomic_read(&adapter->req_q.count) > 0) - return 1; - atomic_inc(&adapter->qdio_outb_full); - return 0; -} - static int zfcp_fsf_req_sbal_get(struct zfcp_adapter *adapter) __releases(&adapter->req_q_lock) __acquires(&adapter->req_q_lock) @@ -1177,8 +1169,8 @@ int zfcp_fsf_send_els(struct zfcp_send_els *els) ZFCP_STATUS_COMMON_UNBLOCKED))) return -EBUSY; - spin_lock(&adapter->req_q_lock); - if (!zfcp_fsf_sbal_available(adapter)) + spin_lock_bh(&adapter->req_q_lock); + if (zfcp_fsf_req_sbal_get(adapter)) goto out; req = zfcp_fsf_req_create(adapter, FSF_QTCB_SEND_ELS, ZFCP_REQ_AUTO_CLEANUP, NULL); @@ -1211,7 +1203,7 @@ int zfcp_fsf_send_els(struct zfcp_send_els *els) failed_send: zfcp_fsf_req_free(req); out: - spin_unlock(&adapter->req_q_lock); + spin_unlock_bh(&adapter->req_q_lock); return ret; } @@ -2324,8 +2316,10 @@ int zfcp_fsf_send_fcp_command_task(struct zfcp_unit *unit, return -EBUSY; spin_lock(&adapter->req_q_lock); - if (!zfcp_fsf_sbal_available(adapter)) + if (atomic_read(&adapter->req_q.count) <= 0) { + atomic_inc(&adapter->qdio_outb_full); goto out; + } req = zfcp_fsf_req_create(adapter, FSF_QTCB_FCP_CMND, ZFCP_REQ_AUTO_CLEANUP, adapter->pool.fsf_req_scsi);