From 04629b7bde553e3703577779f53cb0ba1eddd2c0 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 12 Oct 2011 11:07:04 -0400 Subject: target: Remove unnecessary se_task members This is a squashed version of the following unnecessary se_task structure member removal patches: target: remove the task_execute_queue field in se_task Instead of using a separate flag we can simply do list_emptry checks on t_execute_list if we make sure to always use list_del_init to remove a task from the list. Also factor some duplicate code into a new __transport_remove_task_from_execute_queue helper. target: remove the read-only task_no field in se_task The task_no field never was initialized and only used in debug printks, so kill it. target: remove the task_padded_sg field in se_task This field is only check in one place and not actually needed there. Rationale: - transport_do_task_sg_chain asserts that we have task_sg_chaining set early on - we only make use of the sg_prev_nents field we calculate based on it if there is another sg list that gets chained onto this one, which never happens for the last (or only) task. Signed-off-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_tmr.c | 7 ++-- drivers/target/target_core_transport.c | 59 ++++++++++++++-------------------- include/target/target_core_base.h | 3 -- include/target/target_core_transport.h | 2 ++ 4 files changed, 28 insertions(+), 43 deletions(-) diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c index b5c18648fa2..b8a780fff36 100644 --- a/drivers/target/target_core_tmr.c +++ b/drivers/target/target_core_tmr.c @@ -226,11 +226,8 @@ static void core_tmr_drain_task_list( /* * Remove from task execute list before processing drain_task_list */ - if (atomic_read(&task->task_execute_queue) != 0) { - list_del(&task->t_execute_list); - atomic_set(&task->task_execute_queue, 0); - atomic_dec(&dev->execute_tasks); - } + if (!list_empty(&task->t_execute_list)) + __transport_remove_task_from_execute_queue(task, dev); } spin_unlock_irqrestore(&dev->execute_task_lock, flags); diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 165a60c875a..4a787a0ab06 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -915,38 +915,36 @@ static void transport_add_tasks_from_cmd(struct se_cmd *cmd) spin_lock_irqsave(&dev->execute_task_lock, flags); list_for_each_entry(task, &cmd->t_task_list, t_list) { - if (atomic_read(&task->task_execute_queue)) + if (!list_empty(&task->t_execute_list)) continue; /* * __transport_add_task_to_execute_queue() handles the * SAM Task Attribute emulation if enabled */ __transport_add_task_to_execute_queue(task, task_prev, dev); - atomic_set(&task->task_execute_queue, 1); task_prev = task; } spin_unlock_irqrestore(&dev->execute_task_lock, flags); } -/* transport_remove_task_from_execute_queue(): - * - * - */ +void __transport_remove_task_from_execute_queue(struct se_task *task, + struct se_device *dev) +{ + list_del_init(&task->t_execute_list); + atomic_dec(&dev->execute_tasks); +} + void transport_remove_task_from_execute_queue( struct se_task *task, struct se_device *dev) { unsigned long flags; - if (atomic_read(&task->task_execute_queue) == 0) { - dump_stack(); + if (WARN_ON(list_empty(&task->t_execute_list))) return; - } spin_lock_irqsave(&dev->execute_task_lock, flags); - list_del(&task->t_execute_list); - atomic_set(&task->task_execute_queue, 0); - atomic_dec(&dev->execute_tasks); + __transport_remove_task_from_execute_queue(task, dev); spin_unlock_irqrestore(&dev->execute_task_lock, flags); } @@ -1787,8 +1785,7 @@ static int transport_stop_tasks_for_cmd(struct se_cmd *cmd) spin_lock_irqsave(&cmd->t_state_lock, flags); list_for_each_entry_safe(task, task_tmp, &cmd->t_task_list, t_list) { - pr_debug("task_no[%d] - Processing task %p\n", - task->task_no, task); + pr_debug("Processing task %p\n", task); /* * If the struct se_task has not been sent and is not active, * remove the struct se_task from the execution queue. @@ -1799,8 +1796,7 @@ static int transport_stop_tasks_for_cmd(struct se_cmd *cmd) transport_remove_task_from_execute_queue(task, cmd->se_dev); - pr_debug("task_no[%d] - Removed from execute queue\n", - task->task_no); + pr_debug("Task %p removed from execute queue\n", task); spin_lock_irqsave(&cmd->t_state_lock, flags); continue; } @@ -1814,17 +1810,15 @@ static int transport_stop_tasks_for_cmd(struct se_cmd *cmd) spin_unlock_irqrestore(&cmd->t_state_lock, flags); - pr_debug("task_no[%d] - Waiting to complete\n", - task->task_no); + pr_debug("Task %p waiting to complete\n", task); wait_for_completion(&task->task_stop_comp); - pr_debug("task_no[%d] - Stopped successfully\n", - task->task_no); + pr_debug("Task %p stopped successfully\n", task); spin_lock_irqsave(&cmd->t_state_lock, flags); atomic_dec(&cmd->t_task_cdbs_left); task->task_flags &= ~(TF_ACTIVE | TF_REQUEST_STOP); } else { - pr_debug("task_no[%d] - Did nothing\n", task->task_no); + pr_debug("Task %p - did nothing\n", task); ret++; } @@ -2347,9 +2341,7 @@ check_depth: } task = list_first_entry(&dev->execute_task_list, struct se_task, t_execute_list); - list_del(&task->t_execute_list); - atomic_set(&task->task_execute_queue, 0); - atomic_dec(&dev->execute_tasks); + __transport_remove_task_from_execute_queue(task, dev); spin_unlock_irq(&dev->execute_task_lock); atomic_dec(&dev->depth_left); @@ -2681,9 +2673,9 @@ static int transport_get_sense_data(struct se_cmd *cmd) sense_buffer = dev->transport->get_sense_buffer(task); if (!sense_buffer) { - pr_err("ITT[0x%08x]_TASK[%d]: Unable to locate" + pr_err("ITT[0x%08x]_TASK[%p]: Unable to locate" " sense buffer for task with sense\n", - cmd->se_tfo->get_task_tag(cmd), task->task_no); + cmd->se_tfo->get_task_tag(cmd), task); continue; } spin_unlock_irqrestore(&cmd->t_state_lock, flags); @@ -3897,15 +3889,13 @@ void transport_do_task_sg_chain(struct se_cmd *cmd) /* * For the padded tasks, use the extra SGL vector allocated * in transport_allocate_data_tasks() for the sg_prev_nents - * offset into sg_chain() above.. The last task of a - * multi-task list, or a single task will not have - * task->task_sg_padded set.. + * offset into sg_chain() above. + * + * We do not need the padding for the last task (or a single + * task), but in that case we will never use the sg_prev_nents + * value below which would be incorrect. */ - if (task->task_padded_sg) - sg_prev_nents = (task->task_sg_nents + 1); - else - sg_prev_nents = task->task_sg_nents; - + sg_prev_nents = (task->task_sg_nents + 1); sg_prev = task->task_sg; } /* @@ -3992,7 +3982,6 @@ static int transport_allocate_data_tasks( */ if (cmd->se_tfo->task_sg_chaining && (i < (task_count - 1))) { task_sg_nents_padded = (task->task_sg_nents + 1); - task->task_padded_sg = 1; } else task_sg_nents_padded = task->task_sg_nents; diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 5e3dd1418ba..45291b23bc0 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -409,15 +409,12 @@ struct se_task { u8 task_scsi_status; u8 task_flags; int task_error_status; - bool task_padded_sg; unsigned long long task_lba; - u32 task_no; u32 task_sectors; u32 task_size; enum dma_data_direction task_data_direction; struct se_cmd *task_se_cmd; struct completion task_stop_comp; - atomic_t task_execute_queue; atomic_t task_state_active; struct timer_list task_timer; struct list_head t_list; diff --git a/include/target/target_core_transport.h b/include/target/target_core_transport.h index c93cf0ae37a..c5eb259c2e2 100644 --- a/include/target/target_core_transport.h +++ b/include/target/target_core_transport.h @@ -135,6 +135,8 @@ extern void transport_add_task_to_execute_queue(struct se_task *, struct se_device *); extern void transport_remove_task_from_execute_queue(struct se_task *, struct se_device *); +extern void __transport_remove_task_from_execute_queue(struct se_task *, + struct se_device *); unsigned char *transport_dump_cmd_direction(struct se_cmd *); extern void transport_dump_dev_state(struct se_device *, char *, int *); extern void transport_dump_dev_info(struct se_device *, struct se_lun *, -- cgit v1.2.3-70-g09d2