diff options
| -rw-r--r-- | drivers/target/target_core_device.c | 2 | ||||
| -rw-r--r-- | drivers/target/target_core_internal.h | 1 | ||||
| -rw-r--r-- | drivers/target/target_core_transport.c | 76 | ||||
| -rw-r--r-- | include/target/target_core_base.h | 6 |
4 files changed, 61 insertions, 24 deletions
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index 2d19f0e332b0..20fe28703985 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -758,6 +758,8 @@ struct se_device *target_alloc_device(struct se_hba *hba, const char *name) INIT_LIST_HEAD(&dev->t10_alua.lba_map_list); spin_lock_init(&dev->t10_alua.lba_map_lock); + INIT_WORK(&dev->delayed_cmd_work, target_do_delayed_work); + dev->t10_wwn.t10_dev = dev; dev->t10_alua.t10_dev = dev; diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h index e7b3c6e5d574..e4f072a680d4 100644 --- a/drivers/target/target_core_internal.h +++ b/drivers/target/target_core_internal.h @@ -150,6 +150,7 @@ int transport_dump_vpd_ident(struct t10_vpd *, unsigned char *, int); void transport_clear_lun_ref(struct se_lun *); sense_reason_t target_cmd_size_check(struct se_cmd *cmd, unsigned int size); void target_qf_do_work(struct work_struct *work); +void target_do_delayed_work(struct work_struct *work); bool target_check_wce(struct se_device *dev); bool target_check_fua(struct se_device *dev); void __target_execute_cmd(struct se_cmd *, bool); diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 5cf9e7677926..f52fe4000225 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2021,32 +2021,35 @@ static bool target_handle_task_attr(struct se_cmd *cmd) */ switch (cmd->sam_task_attr) { case TCM_HEAD_TAG: + atomic_inc_mb(&dev->non_ordered); pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n", cmd->t_task_cdb[0]); return false; case TCM_ORDERED_TAG: - atomic_inc_mb(&dev->dev_ordered_sync); + atomic_inc_mb(&dev->delayed_cmd_count); pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n", cmd->t_task_cdb[0]); - - /* - * Execute an ORDERED command if no other older commands - * exist that need to be completed first. - */ - if (!atomic_read(&dev->simple_cmds)) - return false; break; default: /* * For SIMPLE and UNTAGGED Task Attribute commands */ - atomic_inc_mb(&dev->simple_cmds); + atomic_inc_mb(&dev->non_ordered); + + if (atomic_read(&dev->delayed_cmd_count) == 0) + return false; break; } - if (atomic_read(&dev->dev_ordered_sync) == 0) - return false; + if (cmd->sam_task_attr != TCM_ORDERED_TAG) { + atomic_inc_mb(&dev->delayed_cmd_count); + /* + * We will account for this when we dequeue from the delayed + * list. + */ + atomic_dec_mb(&dev->non_ordered); + } spin_lock(&dev->delayed_cmd_lock); list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list); @@ -2054,6 +2057,12 @@ static bool target_handle_task_attr(struct se_cmd *cmd) pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn", cmd->t_task_cdb[0], cmd->sam_task_attr); + /* + * We may have no non ordered cmds when this function started or we + * could have raced with the last simple/head cmd completing, so kick + * the delayed handler here. + */ + schedule_work(&dev->delayed_cmd_work); return true; } @@ -2091,29 +2100,48 @@ EXPORT_SYMBOL(target_execute_cmd); * Process all commands up to the last received ORDERED task attribute which * requires another blocking boundary */ -static void target_restart_delayed_cmds(struct se_device *dev) +void target_do_delayed_work(struct work_struct *work) { - for (;;) { + struct se_device *dev = container_of(work, struct se_device, + delayed_cmd_work); + + spin_lock(&dev->delayed_cmd_lock); + while (!dev->ordered_sync_in_progress) { struct se_cmd *cmd; - spin_lock(&dev->delayed_cmd_lock); - if (list_empty(&dev->delayed_cmd_list)) { - spin_unlock(&dev->delayed_cmd_lock); + if (list_empty(&dev->delayed_cmd_list)) break; - } cmd = list_entry(dev->delayed_cmd_list.next, struct se_cmd, se_delayed_node); + + if (cmd->sam_task_attr == TCM_ORDERED_TAG) { + /* + * Check if we started with: + * [ordered] [simple] [ordered] + * and we are now at the last ordered so we have to wait + * for the simple cmd. + */ + if (atomic_read(&dev->non_ordered) > 0) + break; + + dev->ordered_sync_in_progress = true; + } + list_del(&cmd->se_delayed_node); + atomic_dec_mb(&dev->delayed_cmd_count); spin_unlock(&dev->delayed_cmd_lock); + if (cmd->sam_task_attr != TCM_ORDERED_TAG) + atomic_inc_mb(&dev->non_ordered); + cmd->transport_state |= CMD_T_SENT; __target_execute_cmd(cmd, true); - if (cmd->sam_task_attr == TCM_ORDERED_TAG) - break; + spin_lock(&dev->delayed_cmd_lock); } + spin_unlock(&dev->delayed_cmd_lock); } /* @@ -2131,14 +2159,17 @@ static void transport_complete_task_attr(struct se_cmd *cmd) goto restart; if (cmd->sam_task_attr == TCM_SIMPLE_TAG) { - atomic_dec_mb(&dev->simple_cmds); + atomic_dec_mb(&dev->non_ordered); dev->dev_cur_ordered_id++; } else if (cmd->sam_task_attr == TCM_HEAD_TAG) { + atomic_dec_mb(&dev->non_ordered); dev->dev_cur_ordered_id++; pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n", dev->dev_cur_ordered_id); } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) { - atomic_dec_mb(&dev->dev_ordered_sync); + spin_lock(&dev->delayed_cmd_lock); + dev->ordered_sync_in_progress = false; + spin_unlock(&dev->delayed_cmd_lock); dev->dev_cur_ordered_id++; pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n", @@ -2147,7 +2178,8 @@ static void transport_complete_task_attr(struct se_cmd *cmd) cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET; restart: - target_restart_delayed_cmds(dev); + if (atomic_read(&dev->delayed_cmd_count) > 0) + schedule_work(&dev->delayed_cmd_work); } static void transport_complete_qf(struct se_cmd *cmd) diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 7c9716fe731e..59d7ebb8bbaf 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -781,8 +781,9 @@ struct se_device { atomic_long_t read_bytes; atomic_long_t write_bytes; /* Active commands on this virtual SE device */ - atomic_t simple_cmds; - atomic_t dev_ordered_sync; + atomic_t non_ordered; + bool ordered_sync_in_progress; + atomic_t delayed_cmd_count; atomic_t dev_qf_count; u32 export_count; spinlock_t delayed_cmd_lock; @@ -804,6 +805,7 @@ struct se_device { struct list_head dev_sep_list; struct list_head dev_tmr_list; struct work_struct qf_work_queue; + struct work_struct delayed_cmd_work; struct list_head delayed_cmd_list; struct list_head state_list; struct list_head qf_cmd_list; |