Re: [PATCH v6 15/18] xen/pvcalls: implement the ioworker functions

[Stefano Stabellini]

On Tue, 4 Jul 2017, Juergen Gross wrote:
> On 03/07/17 23:08, Stefano Stabellini wrote:
> > We have one ioworker per socket. Each ioworker goes through the list of
> > outstanding read/write requests. Once all requests have been dealt with,
> > it returns.
> > 
> > We use one atomic counter per socket for "read" operations and one
> > for "write" operations to keep track of the reads/writes to do.
> > 
> > We also use one atomic counter ("io") per ioworker to keep track of how
> > many outstanding requests we have in total assigned to the ioworker. The
> > ioworker finishes when there are none.
> > 
> > Signed-off-by: Stefano Stabellini <stefano@xxxxxxxxxxx>
> > Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
> > CC: boris.ostrovsky@xxxxxxxxxx
> > CC: jgross@xxxxxxxx
> > ---
> >  drivers/xen/pvcalls-back.c | 27 +++++++++++++++++++++++++++
> >  1 file changed, 27 insertions(+)
> > 
> > diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c
> > index 71a42fc..d59c2e4 100644
> > --- a/drivers/xen/pvcalls-back.c
> > +++ b/drivers/xen/pvcalls-back.c
> > @@ -96,8 +96,35 @@ static int pvcalls_back_release_active(struct xenbus_device *dev,
> >  				       struct pvcalls_fedata *fedata,
> >  				       struct sock_mapping *map);
> >  
> > +static void pvcalls_conn_back_read(void *opaque)
> > +{
> > +}
> > +
> > +static int pvcalls_conn_back_write(struct sock_mapping *map)
> > +{
> > +	return 0;
> > +}
> 
> Any reason for letting this function return int? I haven't spotted any
> use of the return value in this or any later patch.

No reason. I'll change it to void.