From: Nicholas Bellinger Date: Sun, 9 Oct 2011 09:19:01 +0000 (-0700) Subject: target: Remove legacy + unused device active I/O shutdown code X-Git-Tag: v3.2-rc1~24^2~53 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ce8762f6cd1e0e6d87a6d0b536635993aef0a697;p=profile%2Fivi%2Fkernel-x86-ivi.git target: Remove legacy + unused device active I/O shutdown code This patch removes the legacy device active I/O shutdown code that was originally called from transport_processing_thread() context during shutdown including transport_processing_shutdown() and transport_release_all_cmds(). This is due to the fact that in modern configfs control plane code by the time shutdown of an se_device instance in transport_processing_thread() is allowed to occur via: rmdir /sys/kernel/config/target/core/$HBA/$DEV all active I/O will already have been ceased while removing active configfs fabric Port/LUN symlinks. Eg: the removal of an active se_device is protected by inter-module VFS references from active Port/LUN symlinks. Two WARN_ON() checks have been added in their place before exiting transport_processing_thread() to watch out for any leaked descriptors. Cc: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 36fb39c..ee73f10 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -1040,41 +1040,6 @@ void transport_dump_dev_state( *bl += sprintf(b + *bl, " "); } -/* transport_release_all_cmds(): - * - * - */ -static void transport_release_all_cmds(struct se_device *dev) -{ - struct se_cmd *cmd, *tcmd; - int bug_out = 0, t_state; - unsigned long flags; - - spin_lock_irqsave(&dev->dev_queue_obj.cmd_queue_lock, flags); - list_for_each_entry_safe(cmd, tcmd, &dev->dev_queue_obj.qobj_list, - se_queue_node) { - t_state = cmd->t_state; - list_del_init(&cmd->se_queue_node); - spin_unlock_irqrestore(&dev->dev_queue_obj.cmd_queue_lock, - flags); - - pr_err("Releasing ITT: 0x%08x, i_state: %u," - " t_state: %u directly\n", - cmd->se_tfo->get_task_tag(cmd), - cmd->se_tfo->get_cmd_state(cmd), t_state); - - transport_put_cmd(cmd); - bug_out = 1; - - spin_lock_irqsave(&dev->dev_queue_obj.cmd_queue_lock, flags); - } - spin_unlock_irqrestore(&dev->dev_queue_obj.cmd_queue_lock, flags); -#if 0 - if (bug_out) - BUG(); -#endif -} - void transport_dump_vpd_proto_id( struct t10_vpd *vpd, unsigned char *p_buf, @@ -4859,180 +4824,6 @@ int transport_generic_do_tmr(struct se_cmd *cmd) return 0; } -/* - * Called with spin_lock_irq(&dev->execute_task_lock); held - * - */ -static struct se_task * -transport_get_task_from_state_list(struct se_device *dev) -{ - struct se_task *task; - - if (list_empty(&dev->state_task_list)) - return NULL; - - list_for_each_entry(task, &dev->state_task_list, t_state_list) - break; - - list_del(&task->t_state_list); - atomic_set(&task->task_state_active, 0); - - return task; -} - -static void transport_processing_shutdown(struct se_device *dev) -{ - struct se_cmd *cmd; - struct se_task *task; - unsigned long flags; - /* - * Empty the struct se_device's struct se_task state list. - */ - spin_lock_irqsave(&dev->execute_task_lock, flags); - while ((task = transport_get_task_from_state_list(dev))) { - if (!task->task_se_cmd) { - pr_err("task->task_se_cmd is NULL!\n"); - continue; - } - cmd = task->task_se_cmd; - - spin_unlock_irqrestore(&dev->execute_task_lock, flags); - - spin_lock_irqsave(&cmd->t_state_lock, flags); - - pr_debug("PT: cmd: %p task: %p ITT: 0x%08x," - " i_state: %d, t_state/def_t_state:" - " %d/%d cdb: 0x%02x\n", cmd, task, - cmd->se_tfo->get_task_tag(cmd), - cmd->se_tfo->get_cmd_state(cmd), - cmd->t_state, cmd->deferred_t_state, - cmd->t_task_cdb[0]); - pr_debug("PT: ITT[0x%08x] - t_tasks: %d t_task_cdbs_left:" - " %d t_task_cdbs_sent: %d -- t_transport_active: %d" - " t_transport_stop: %d t_transport_sent: %d\n", - cmd->se_tfo->get_task_tag(cmd), - cmd->t_task_list_num, - atomic_read(&cmd->t_task_cdbs_left), - atomic_read(&cmd->t_task_cdbs_sent), - atomic_read(&cmd->t_transport_active), - atomic_read(&cmd->t_transport_stop), - atomic_read(&cmd->t_transport_sent)); - - if (atomic_read(&task->task_active)) { - atomic_set(&task->task_stop, 1); - spin_unlock_irqrestore( - &cmd->t_state_lock, flags); - - pr_debug("Waiting for task: %p to shutdown for dev:" - " %p\n", task, dev); - wait_for_completion(&task->task_stop_comp); - pr_debug("Completed task: %p shutdown for dev: %p\n", - task, dev); - - spin_lock_irqsave(&cmd->t_state_lock, flags); - atomic_dec(&cmd->t_task_cdbs_left); - - atomic_set(&task->task_active, 0); - atomic_set(&task->task_stop, 0); - } else { - if (atomic_read(&task->task_execute_queue) != 0) - transport_remove_task_from_execute_queue(task, dev); - } - __transport_stop_task_timer(task, &flags); - - if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) { - spin_unlock_irqrestore( - &cmd->t_state_lock, flags); - - pr_debug("Skipping task: %p, dev: %p for" - " t_task_cdbs_ex_left: %d\n", task, dev, - atomic_read(&cmd->t_task_cdbs_ex_left)); - - spin_lock_irqsave(&dev->execute_task_lock, flags); - continue; - } - - if (atomic_read(&cmd->t_transport_active)) { - pr_debug("got t_transport_active = 1 for task: %p, dev:" - " %p\n", task, dev); - - if (atomic_read(&cmd->t_fe_count)) { - spin_unlock_irqrestore( - &cmd->t_state_lock, flags); - transport_send_check_condition_and_sense( - cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, - 0); - transport_remove_cmd_from_queue(cmd, - &cmd->se_dev->dev_queue_obj); - - transport_lun_remove_cmd(cmd); - transport_cmd_check_stop(cmd, 1, 0); - } else { - spin_unlock_irqrestore( - &cmd->t_state_lock, flags); - - transport_remove_cmd_from_queue(cmd, - &cmd->se_dev->dev_queue_obj); - - transport_lun_remove_cmd(cmd); - - if (transport_cmd_check_stop(cmd, 1, 0)) - transport_put_cmd(cmd); - } - - spin_lock_irqsave(&dev->execute_task_lock, flags); - continue; - } - pr_debug("Got t_transport_active = 0 for task: %p, dev: %p\n", - task, dev); - - if (atomic_read(&cmd->t_fe_count)) { - spin_unlock_irqrestore( - &cmd->t_state_lock, flags); - transport_send_check_condition_and_sense(cmd, - TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); - transport_remove_cmd_from_queue(cmd, - &cmd->se_dev->dev_queue_obj); - - transport_lun_remove_cmd(cmd); - transport_cmd_check_stop(cmd, 1, 0); - } else { - spin_unlock_irqrestore( - &cmd->t_state_lock, flags); - - transport_remove_cmd_from_queue(cmd, - &cmd->se_dev->dev_queue_obj); - transport_lun_remove_cmd(cmd); - - if (transport_cmd_check_stop(cmd, 1, 0)) - transport_put_cmd(cmd); - } - - spin_lock_irqsave(&dev->execute_task_lock, flags); - } - spin_unlock_irqrestore(&dev->execute_task_lock, flags); - /* - * Empty the struct se_device's struct se_cmd list. - */ - while ((cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj))) { - - pr_debug("From Device Queue: cmd: %p t_state: %d\n", - cmd, cmd->t_state); - - if (atomic_read(&cmd->t_fe_count)) { - transport_send_check_condition_and_sense(cmd, - TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); - - transport_lun_remove_cmd(cmd); - transport_cmd_check_stop(cmd, 1, 0); - } else { - transport_lun_remove_cmd(cmd); - if (transport_cmd_check_stop(cmd, 1, 0)) - transport_put_cmd(cmd); - } - } -} - /* transport_processing_thread(): * * @@ -5052,14 +4843,6 @@ static int transport_processing_thread(void *param) if (ret < 0) goto out; - spin_lock_irq(&dev->dev_status_lock); - if (dev->dev_status & TRANSPORT_DEVICE_SHUTDOWN) { - spin_unlock_irq(&dev->dev_status_lock); - transport_processing_shutdown(dev); - continue; - } - spin_unlock_irq(&dev->dev_status_lock); - get_cmd: __transport_execute_tasks(dev); @@ -5135,7 +4918,8 @@ get_cmd: } out: - transport_release_all_cmds(dev); + WARN_ON(!list_empty(&dev->state_task_list)); + WARN_ON(!list_empty(&dev->dev_queue_obj.qobj_list)); dev->process_thread = NULL; return 0; }