Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 124d6db0 authored by Josef Bacik's avatar Josef Bacik Committed by Jens Axboe
Browse files

nbd: use our own workqueue for recv threads 



Since we are in the memory reclaim path we need our recv work to be on a
workqueue that has WQ_MEM_RECLAIM set so we can avoid deadlocks.  Also
set WQ_HIGHPRI since we are in the completion path for IO.

Signed-off-by: default avatarJosef Bacik <jbacik@fb.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent 72f2f8f6

drivers/block/nbd.c

+11 −2
Original line number Diff line number Diff line
@@ -91,6 +91,7 @@ static struct dentry *nbd_dbg_dir; 
static unsigned int nbds_max = 16;

static struct nbd_device *nbd_dev;

static int max_part;

static struct workqueue_struct *recv_workqueue;



static inline struct device *nbd_to_dev(struct nbd_device *nbd)

{
@@ -781,7 +782,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, 
			INIT_WORK(&args[i].work, recv_work);

			args[i].nbd = nbd;

			args[i].index = i;

			queue_work(system_long_wq, &args[i].work);

			queue_work(recv_workqueue, &args[i].work);

		}

		wait_event_interruptible(nbd->recv_wq,

					 atomic_read(&nbd->recv_threads) == 0);
@@ -1030,10 +1031,16 @@ static int __init nbd_init(void) 


	if (nbds_max > 1UL << (MINORBITS - part_shift))

		return -EINVAL;

	recv_workqueue = alloc_workqueue("knbd-recv",

					 WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);

	if (!recv_workqueue)

		return -ENOMEM;



	nbd_dev = kcalloc(nbds_max, sizeof(*nbd_dev), GFP_KERNEL);

	if (!nbd_dev)

	if (!nbd_dev) {

		destroy_workqueue(recv_workqueue);

		return -ENOMEM;

	}



	for (i = 0; i < nbds_max; i++) {

		struct request_queue *q;
@@ -1113,6 +1120,7 @@ static int __init nbd_init(void) 
		put_disk(nbd_dev[i].disk);

	}

	kfree(nbd_dev);

	destroy_workqueue(recv_workqueue);

	return err;

}
@@ -1132,6 +1140,7 @@ static void __exit nbd_cleanup(void) 
			put_disk(disk);

		}

	}

	destroy_workqueue(recv_workqueue);

	unregister_blkdev(NBD_MAJOR, "nbd");

	kfree(nbd_dev);

	printk(KERN_INFO "nbd: unregistered device at major %d\n", NBD_MAJOR);