On 9/5/2021 4:10 PM, Leon Romanovsky wrote:
On Sun, Sep 05, 2021 at 02:16:58PM +0300, Max Gurtovoy wrote:
On 9/5/2021 1:19 PM, Leon Romanovsky wrote:
On Sun, Sep 05, 2021 at 12:19:09PM +0300, Max Gurtovoy wrote:
On 9/5/2021 11:49 AM, Chaitanya Kulkarni wrote:
On 9/5/2021 12:46 AM, Leon Romanovsky wrote:
+static unsigned int num_request_queues;
+module_param_cb(num_request_queues, &queue_count_ops,
&num_request_queues,
+ 0644);
+MODULE_PARM_DESC(num_request_queues,
+ "Number of request queues to use for blk device.
Should > 0");
+
Won't it limit all virtio block devices to the same limit?
It is very common to see multiple virtio-blk devices on the same system
and they probably need different limits.
Thanks
Without looking into the code, that can be done adding a configfs
interface and overriding a global value (module param) when it is set
from
configfs.
You have many ways to overcome this issue.
For example:
# ls -l /sys/block/vda/mq/
drwxr-xr-x 18 root root 0 Sep 5 12:14 0
drwxr-xr-x 18 root root 0 Sep 5 12:14 1
drwxr-xr-x 18 root root 0 Sep 5 12:14 2
drwxr-xr-x 18 root root 0 Sep 5 12:14 3
# echo virtio0 > /sys/bus/virtio/drivers/virtio_blk/unbind
# echo 8 > /sys/module/virtio_blk/parameters/num_request_queues
This is global to all virtio-blk devices.
You define a global module param but you bind/unbind a specific device.
Do you have a better way to control it ?
One of the possible solutions will be to extend virtio bus to allow
setting of such pre-probe parameters. However I don't know if it is
really worth doing it,
So lets keep it as it is now.
Thanks.
if the device is already probed, it's too late to change the queue_num.
# echo virtio0 > /sys/bus/virtio/drivers/virtio_blk/bind
# ls -l /sys/block/vda/mq/
drwxr-xr-x 10 root root 0 Sep 5 12:17 0
drwxr-xr-x 10 root root 0 Sep 5 12:17 1
drwxr-xr-x 10 root root 0 Sep 5 12:17 2
drwxr-xr-x 10 root root 0 Sep 5 12:17 3
drwxr-xr-x 10 root root 0 Sep 5 12:17 4
drwxr-xr-x 10 root root 0 Sep 5 12:17 5
drwxr-xr-x 10 root root 0 Sep 5 12:17 6
drwxr-xr-x 10 root root 0 Sep 5 12:17 7
-Max.
