On Tue, Jan 25, 2022 at 12:23:06PM +0100, Alexander Lobakin wrote:
> From: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx>
> Date: Mon, 24 Jan 2022 17:55:41 +0100
>
> > With the upcoming introduction of batching to XSK data path,
> > performance wise it will be the best to have the ring descriptor count
> > to be aligned to power of 2.
> >
> > Check if rings sizes that user is going to attach the XSK socket fulfill
> > the condition above. For Tx side, although check is being done against
> > the Tx queue and in the end the socket will be attached to the XDP
> > queue, it is fine since XDP queues get the ring->count setting from Tx
> > queues.
> >
> > Suggested-by: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx>
> > Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx>
> > ---
> > drivers/net/ethernet/intel/ice/ice_xsk.c | 9 +++++++++
> > 1 file changed, 9 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c
> > index 2388837d6d6c..0350f9c22c62 100644
> > --- a/drivers/net/ethernet/intel/ice/ice_xsk.c
> > +++ b/drivers/net/ethernet/intel/ice/ice_xsk.c
> > @@ -327,6 +327,14 @@ int ice_xsk_pool_setup(struct ice_vsi *vsi, struct xsk_buff_pool *pool, u16 qid)
> > bool if_running, pool_present = !!pool;
> > int ret = 0, pool_failure = 0;
> >
> > + if (!is_power_of_2(vsi->rx_rings[qid]->count) ||
> > + !is_power_of_2(vsi->tx_rings[qid]->count)) {
> > + netdev_err(vsi->netdev,
> > + "Please align ring sizes at idx %d to power of 2\n", qid);
>
> Ideally I'd pass xdp->extack from ice_xdp() to print this message
> directly in userspace (note that NL_SET_ERR_MSG{,_MOD}() don't
> support string formatting, but the user already knows QID at this
> point).
I thought about that as well but it seemed to me kinda off to have a
single extack usage in here. Updating the rest of error paths in
ice_xsk_pool_setup() to make use of extack is a candidate for a separate
patch to me.
WDYT?
>
> > + pool_failure = -EINVAL;
> > + goto failure;
> > + }
> > +
> > if_running = netif_running(vsi->netdev) && ice_is_xdp_ena_vsi(vsi);
> >
> > if (if_running) {
> > @@ -349,6 +357,7 @@ int ice_xsk_pool_setup(struct ice_vsi *vsi, struct xsk_buff_pool *pool, u16 qid)
> > netdev_err(vsi->netdev, "ice_qp_ena error = %d\n", ret);
> > }
> >
> > +failure:
> > if (pool_failure) {
> > netdev_err(vsi->netdev, "Could not %sable buffer pool, error = %d\n",
> > pool_present ? "en" : "dis", pool_failure);
> > --
> > 2.33.1
>
> Thanks,
> Al
