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

From: Juergen Gross
Date: Tue Jul 04 2017 - 03:48:33 EST


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.


Juergen