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, > > 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. > > > > > >
