Re: [PATCH] usb/mos7720: process deferred urbs in a workqueue

[Davidlohr Bueso]

On Mon, 09 Nov 2020, Oliver Neukum wrote:

> Am Donnerstag, den 05.11.2020, 22:17 -0800 schrieb Davidlohr Bueso:
> > @@ -1888,16 +1732,8 @@ static void mos7720_release(struct usb_serial *serial)
> >                 usb_set_serial_data(serial, NULL);
> >                 mos_parport->serial = NULL;
> >
> > -               /* if tasklet currently scheduled, wait for it to complete */
> > -               tasklet_kill(&mos_parport->urb_tasklet);
> > -
> > -               /* unlink any urbs sent by the tasklet  */
> > -               spin_lock_irqsave(&mos_parport->listlock, flags);
> > -               list_for_each_entry(urbtrack,
> > -                                   &mos_parport->active_urbs,
> > -                                   urblist_entry)
> > -                       usb_unlink_urb(urbtrack->urb);
> > -               spin_unlock_irqrestore(&mos_parport->listlock, flags);
> > +               /* if work is currently scheduled, wait for it to complete */
> > +               cancel_work_sync(&mos_parport->work);
> >                 parport_del_port(mos_parport->pp);
> >
> >                 kref_put(&mos_parport->ref_count, destroy_mos_parport);
>
> Hi,
>
> do you really want to cancel as opposed to wait for work in release()?

Well I tried to maintain the current semantics here. tasklet_kill() is
equivalent to cancel_work_sync() in that they both wait for the delayed
execution to finish running and guarantee that it is no longer queued.

Thanks,
Davidlohr