On Sun, Sep 05, 2021 at 01:20:24PM +0300, Leon Romanovsky wrote: > On Sun, Sep 05, 2021 at 01:49:46AM -0700, 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. > > So why should we do double work instead of providing one working > interface from the beginning? > > Thanks > > > > > The main way to do it is really from the hypervisor. This one is a pretty blunt instrument, Max here says it's useful to reduce memory usage of the driver. If that's the usecase then a global limit seems sufficient. -- MST
