On Mon, 9 May 2016 09:47:08 -0700
Alexander Duyck <alexander.du...@gmail.com> wrote:
> On Mon, May 9, 2016 at 6:44 AM, Jesper Dangaard Brouer
> <bro...@redhat.com> wrote:
> > Activate the bulk alloc API, simply by changing mlx4 from using
> > netdev_alloc_skb() to using napi_alloc_skb().
>
> This patch is just enabling the napi_alloc_skb call. You don't need
> to call out that it is enabling bulk allocations. This patch could
> stand on its own without needing to make reference to the bulk
> allocation API because there is enough of a gain from napi_alloc_skb
> replacing netdev_alloc_skb.
Okay, I see you point.
> > Signed-off-by: Jesper Dangaard Brouer <bro...@redhat.com>
> > ---
> > drivers/net/ethernet/mellanox/mlx4/en_rx.c | 7 ++++---
> > 1 file changed, 4 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> > b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> > index 8ef6875b6cf9..84fd6db5a176 100644
> > --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> > +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> > @@ -577,14 +577,15 @@ fail:
> > static struct sk_buff *mlx4_en_rx_skb(struct mlx4_en_priv *priv,
> > struct mlx4_en_rx_desc *rx_desc,
> > struct mlx4_en_rx_alloc *frags,
> > - unsigned int length)
> > + unsigned int length,
> > + struct napi_struct *napi)
>
> Instead of passing the NAPI structure you could just pass the
> mlx4_en_cq pointer to be used by the NAPI alloc function. In addition
> you might try adding the new parameter before length since that way
> the pointers are in one block followed by integers in a tapering
> length order.
Okay, will adjust.
> > {
> > struct sk_buff *skb;
> > void *va;
> > int used_frags;
> > dma_addr_t dma;
> >
> > - skb = netdev_alloc_skb(priv->dev, SMALL_PACKET_SIZE + NET_IP_ALIGN);
> > + skb = napi_alloc_skb(napi, SMALL_PACKET_SIZE + NET_IP_ALIGN);
>
> The NET_IP_ALIGN is redundant as napi_alloc_skb already takes are of
> adding that and NET_SKB_PAD.
Thanks for catching this.
> > if (!skb) {
> > en_dbg(RX_ERR, priv, "Failed allocating skb\n");
> > return NULL;
> > @@ -932,7 +933,7 @@ int mlx4_en_process_rx_cq(struct net_device *dev,
> > struct mlx4_en_cq *cq, int bud
> > }
> >
> > /* GRO not possible, complete processing here */
> > - skb = mlx4_en_rx_skb(priv, rx_desc, frags, length);
> > + skb = mlx4_en_rx_skb(priv, rx_desc, frags, length,
> > &cq->napi);
> > if (!skb) {
> > ring->dropped++;
> > goto next;
> >
--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
Author of http://www.iptv-analyzer.org
LinkedIn: http://www.linkedin.com/in/brouer
