On Tue, Feb 12, 2019 at 04:08:37PM +0100, Lorenzo Bianconi wrote: > > > > What unnecessary operation ? > > > > > > the ones in mt76u_fill_bulk_urb() > > > > Your patches also add extra operations on hotpath due to urb->num_sgs and > > dev->usb.sg_en checks. > > here I guess you should use mt76u_check_sg() instead of > udev->bus->sg_tablesize > 0 so I think you need to precompute it since it is in > the hotpath It's not necessary. If udev->bus->sg_tablesize > 0 is true and rest of mt76u_check_sg() is not, we will submit urb with urb->num_sgs = 1 to usb host driver, what is fine. > Moreover the RFC series has been tested by multiple users and on multiple > devices I know. Perhaps you could test my patch on rpi ? Stanislaw
