From 65586d51e0986be574118286c3d0007e903a2add Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 30 Nov 2011 01:25:21 -0800 Subject: target: Drop se_device TCQ queue_depth usage from I/O path Historically, pSCSI devices have been the ones that required target-core to enforce a per se_device->depth_left. This patch changes target-core to no longer (by default) enforce a per se_device->depth_left or sleep in transport_tcq_window_closed() when we out of queue slots for all backend export cases. Cc: Christoph Hellwig Cc: Roland Dreier Cc: Joern Engel Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_device.c | 7 ------ drivers/target/target_core_pscsi.c | 1 - drivers/target/target_core_transport.c | 39 ++-------------------------------- include/target/target_core_base.h | 1 - 4 files changed, 2 insertions(+), 46 deletions(-) diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index 1f74de25a92f..0c5992f0d946 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -1132,8 +1132,6 @@ int se_dev_set_emulate_rest_reord(struct se_device *dev, int flag) */ int se_dev_set_queue_depth(struct se_device *dev, u32 queue_depth) { - u32 orig_queue_depth = dev->queue_depth; - if (atomic_read(&dev->dev_export_obj.obj_access_count)) { pr_err("dev[%p]: Unable to change SE Device TCQ while" " dev_export_obj: %d count exists\n", dev, @@ -1167,11 +1165,6 @@ int se_dev_set_queue_depth(struct se_device *dev, u32 queue_depth) } dev->se_sub_dev->se_dev_attrib.queue_depth = dev->queue_depth = queue_depth; - if (queue_depth > orig_queue_depth) - atomic_add(queue_depth - orig_queue_depth, &dev->depth_left); - else if (queue_depth < orig_queue_depth) - atomic_sub(orig_queue_depth - queue_depth, &dev->depth_left); - pr_debug("dev[%p]: SE Device TCQ Depth changed to: %u\n", dev, queue_depth); return 0; diff --git a/drivers/target/target_core_pscsi.c b/drivers/target/target_core_pscsi.c index b73a399cdd54..d35467d42e12 100644 --- a/drivers/target/target_core_pscsi.c +++ b/drivers/target/target_core_pscsi.c @@ -350,7 +350,6 @@ static struct se_device *pscsi_add_device_to_list( * scsi_device_put() and the pdv->pdv_sd cleared. */ pdv->pdv_sd = sd; - dev = transport_add_device_to_core_hba(hba, &pscsi_template, se_dev, dev_flags, pdv, &dev_limits, NULL, NULL); diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 1cc7e920ab0b..7c2def7e2593 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -691,12 +691,6 @@ void transport_complete_task(struct se_task *task, int success) struct se_cmd *cmd = task->task_se_cmd; struct se_device *dev = cmd->se_dev; unsigned long flags; -#if 0 - pr_debug("task: %p CDB: 0x%02x obj_ptr: %p\n", task, - cmd->t_task_cdb[0], dev); -#endif - if (dev) - atomic_inc(&dev->depth_left); spin_lock_irqsave(&cmd->t_state_lock, flags); task->task_flags &= ~TF_ACTIVE; @@ -971,9 +965,8 @@ void transport_dump_dev_state( break; } - *bl += sprintf(b + *bl, " Execute/Left/Max Queue Depth: %d/%d/%d", - atomic_read(&dev->execute_tasks), atomic_read(&dev->depth_left), - dev->queue_depth); + *bl += sprintf(b + *bl, " Execute/Max Queue Depth: %d/%d", + atomic_read(&dev->execute_tasks), dev->queue_depth); *bl += sprintf(b + *bl, " SectorSize: %u MaxSectors: %u\n", dev->se_sub_dev->se_dev_attrib.block_size, dev->se_sub_dev->se_dev_attrib.max_sectors); *bl += sprintf(b + *bl, " "); @@ -1328,9 +1321,6 @@ struct se_device *transport_add_device_to_core_hba( spin_lock_init(&dev->se_port_lock); spin_lock_init(&dev->se_tmr_lock); spin_lock_init(&dev->qf_cmd_lock); - - dev->queue_depth = dev_limits->queue_depth; - atomic_set(&dev->depth_left, dev->queue_depth); atomic_set(&dev->dev_ordered_id, 0); se_dev_set_default_attribs(dev, dev_limits); @@ -1982,18 +1972,6 @@ static void transport_set_supported_SAM_opcode(struct se_cmd *se_cmd) spin_unlock_irqrestore(&se_cmd->t_state_lock, flags); } -static inline int transport_tcq_window_closed(struct se_device *dev) -{ - if (dev->dev_tcq_window_closed++ < - PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD) { - msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT); - } else - msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG); - - wake_up_interruptible(&dev->dev_queue_obj.thread_wq); - return 0; -} - /* * Called from Fabric Module context from transport_execute_tasks() * @@ -2126,16 +2104,7 @@ static int __transport_execute_tasks(struct se_device *dev) struct se_task *task = NULL; unsigned long flags; - /* - * Check if there is enough room in the device and HBA queue to send - * struct se_tasks to the selected transport. - */ check_depth: - if (!atomic_read(&dev->depth_left)) - return transport_tcq_window_closed(dev); - - dev->dev_tcq_window_closed = 0; - spin_lock_irq(&dev->execute_task_lock); if (list_empty(&dev->execute_task_list)) { spin_unlock_irq(&dev->execute_task_lock); @@ -2146,10 +2115,7 @@ check_depth: __transport_remove_task_from_execute_queue(task, dev); spin_unlock_irq(&dev->execute_task_lock); - atomic_dec(&dev->depth_left); - cmd = task->task_se_cmd; - spin_lock_irqsave(&cmd->t_state_lock, flags); task->task_flags |= (TF_ACTIVE | TF_SENT); atomic_inc(&cmd->t_task_cdbs_sent); @@ -2170,7 +2136,6 @@ check_depth: spin_unlock_irqrestore(&cmd->t_state_lock, flags); atomic_set(&cmd->t_transport_sent, 0); transport_stop_tasks_for_cmd(cmd); - atomic_inc(&dev->depth_left); transport_generic_request_failure(cmd); } diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 28190dc10eef..cd4caf3a598f 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -798,7 +798,6 @@ struct se_device { spinlock_t stats_lock; /* Active commands on this virtual SE device */ atomic_t simple_cmds; - atomic_t depth_left; atomic_t dev_ordered_id; atomic_t execute_tasks; atomic_t dev_ordered_sync; -- cgit v1.2.3