On 05/25/2016 12:55 AM, mchristi@xxxxxxxxxx wrote:
+ spin_lock_irq(q->queue_lock); + wait_event_lock_irq(q->reset_wq, + !queue_flag_test_and_set(QUEUE_FLAG_RESETTING, q), + *q->queue_lock); + if (blk_queue_dead(q)) { + rc = -ENODEV; + spin_unlock_irq(q->queue_lock); + goto done; + } + spin_unlock_irq(q->queue_lock);
Is the flag QUEUE_FLAG_RESETTING used to serialize blk_reset_queue() calls? If so, please consider using a mutex instead. Lockdep can detect lock inversion for mutexes and spinlocks but not for serialization that is based on wait_event_lock_irq() loops.
+ if (q->mq_ops) { + blk_mq_stop_hw_queues(q); + blk_mq_freeze_queue(q); + + eh_rc = q->mq_ops->reset(q); + + blk_mq_unfreeze_queue(q); + blk_mq_start_stopped_hw_queues(q, true); + } else if (q->reset_fn) { + spin_lock_irq(q->queue_lock); + blk_stop_queue(q); + spin_unlock_irq(q->queue_lock); + + while (q->request_fn_active) + msleep(10); + + eh_rc = q->reset_fn(q); + + spin_lock_irq(q->queue_lock); + blk_start_queue(q); + spin_unlock_irq(q->queue_lock); + }
Some of the above code is similar to some of the code in scsi_internal_device_block() and scsi_internal_device_unblock(). Have you considered to avoid this duplication by introducing helpers in the block layer for blocking and unblocking queues?
Thanks, Bart. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html