On Fri, 10 Oct 2014, Ilya Dryomov wrote:
> Using one queue per device doesn't make much sense given that our
> workfn processes "devices" and not "requests". Switch to a single
> workqueue for all devices.
>
> Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxxx>
Reviewed-by: Sage Weil <sage@xxxxxxxxxx>
> ---
> drivers/block/rbd.c | 33 ++++++++++++++++++---------------
> 1 file changed, 18 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
> index 0a54c588e433..be8d44af6ae1 100644
> --- a/drivers/block/rbd.c
> +++ b/drivers/block/rbd.c
> @@ -342,7 +342,6 @@ struct rbd_device {
>
> struct list_head rq_queue; /* incoming rq queue */
> spinlock_t lock; /* queue, flags, open_count */
> - struct workqueue_struct *rq_wq;
> struct work_struct rq_work;
>
> struct rbd_image_header header;
> @@ -402,6 +401,8 @@ static struct kmem_cache *rbd_segment_name_cache;
> static int rbd_major;
> static DEFINE_IDA(rbd_dev_id_ida);
>
> +static struct workqueue_struct *rbd_wq;
> +
> /*
> * Default to false for now, as single-major requires >= 0.75 version of
> * userspace rbd utility.
> @@ -3452,7 +3453,7 @@ static void rbd_request_fn(struct request_queue *q)
> }
>
> if (queued)
> - queue_work(rbd_dev->rq_wq, &rbd_dev->rq_work);
> + queue_work(rbd_wq, &rbd_dev->rq_work);
> }
>
> /*
> @@ -5242,16 +5243,9 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
> set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
> set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only);
>
> - rbd_dev->rq_wq = alloc_workqueue("%s", WQ_MEM_RECLAIM, 0,
> - rbd_dev->disk->disk_name);
> - if (!rbd_dev->rq_wq) {
> - ret = -ENOMEM;
> - goto err_out_mapping;
> - }
> -
> ret = rbd_bus_add_dev(rbd_dev);
> if (ret)
> - goto err_out_workqueue;
> + goto err_out_mapping;
>
> /* Everything's ready. Announce the disk to the world. */
>
> @@ -5263,9 +5257,6 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
>
> return ret;
>
> -err_out_workqueue:
> - destroy_workqueue(rbd_dev->rq_wq);
> - rbd_dev->rq_wq = NULL;
> err_out_mapping:
> rbd_dev_mapping_clear(rbd_dev);
> err_out_disk:
> @@ -5512,7 +5503,6 @@ static void rbd_dev_device_release(struct device *dev)
> {
> struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
>
> - destroy_workqueue(rbd_dev->rq_wq);
> rbd_free_disk(rbd_dev);
> clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
> rbd_dev_mapping_clear(rbd_dev);
> @@ -5716,11 +5706,21 @@ static int __init rbd_init(void)
> if (rc)
> return rc;
>
> + /*
> + * The number of active work items is limited by the number of
> + * rbd devices, so leave @max_active at default.
> + */
> + rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0);
> + if (!rbd_wq) {
> + rc = -ENOMEM;
> + goto err_out_slab;
> + }
> +
> if (single_major) {
> rbd_major = register_blkdev(0, RBD_DRV_NAME);
> if (rbd_major < 0) {
> rc = rbd_major;
> - goto err_out_slab;
> + goto err_out_wq;
> }
> }
>
> @@ -5738,6 +5738,8 @@ static int __init rbd_init(void)
> err_out_blkdev:
> if (single_major)
> unregister_blkdev(rbd_major, RBD_DRV_NAME);
> +err_out_wq:
> + destroy_workqueue(rbd_wq);
> err_out_slab:
> rbd_slab_exit();
> return rc;
> @@ -5749,6 +5751,7 @@ static void __exit rbd_exit(void)
> rbd_sysfs_cleanup();
> if (single_major)
> unregister_blkdev(rbd_major, RBD_DRV_NAME);
> + destroy_workqueue(rbd_wq);
> rbd_slab_exit();
> }
>
> --
> 1.7.10.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
>
--
To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
