On Wed, May 30, 2018 at 11:01 AM, Jesper Dangaard Brouer
<bro...@redhat.com> wrote:
> The XDP_REDIRECT map devmap can avoid using ndo_xdp_flush, by instead
> instructing ndo_xdp_xmit to flush via XDP_XMIT_FLUSH flag in
> appropriate places.
>
> Notice after this patch it is possible to remove ndo_xdp_flush
> completely, as this is the last user of ndo_xdp_flush. This is left
> for later patches, to keep driver changes separate.
>
> Signed-off-by: Jesper Dangaard Brouer <bro...@redhat.com>
> ---
> kernel/bpf/devmap.c | 20 +++++++-------------
> 1 file changed, 7 insertions(+), 13 deletions(-)
>
> diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
> index 04fbd75a5274..9c846a7a8cff 100644
> --- a/kernel/bpf/devmap.c
> +++ b/kernel/bpf/devmap.c
> @@ -217,7 +217,7 @@ void __dev_map_insert_ctx(struct bpf_map *map, u32 bit)
> }
>
> static int bq_xmit_all(struct bpf_dtab_netdev *obj,
> - struct xdp_bulk_queue *bq)
> + struct xdp_bulk_queue *bq, bool flush)
How about we use "int flags" instead of "bool flush" for easier extension?
Thanks,
Song
> {
> struct net_device *dev = obj->dev;
> int sent = 0, drops = 0, err = 0;
> @@ -232,7 +232,8 @@ static int bq_xmit_all(struct bpf_dtab_netdev *obj,
> prefetch(xdpf);
> }
>
> - sent = dev->netdev_ops->ndo_xdp_xmit(dev, bq->count, bq->q, 0);
> + sent = dev->netdev_ops->ndo_xdp_xmit(dev, bq->count, bq->q,
> + flush ? XDP_XMIT_FLUSH : 0);
> if (sent < 0) {
> err = sent;
> sent = 0;
> @@ -276,7 +277,6 @@ void __dev_map_flush(struct bpf_map *map)
> for_each_set_bit(bit, bitmap, map->max_entries) {
> struct bpf_dtab_netdev *dev =
> READ_ONCE(dtab->netdev_map[bit]);
> struct xdp_bulk_queue *bq;
> - struct net_device *netdev;
>
> /* This is possible if the dev entry is removed by user space
> * between xdp redirect and flush op.
> @@ -287,10 +287,7 @@ void __dev_map_flush(struct bpf_map *map)
> __clear_bit(bit, bitmap);
>
> bq = this_cpu_ptr(dev->bulkq);
> - bq_xmit_all(dev, bq);
> - netdev = dev->dev;
> - if (likely(netdev->netdev_ops->ndo_xdp_flush))
> - netdev->netdev_ops->ndo_xdp_flush(netdev);
> + bq_xmit_all(dev, bq, true);
> }
> }
>
> @@ -320,7 +317,7 @@ static int bq_enqueue(struct bpf_dtab_netdev *obj, struct
> xdp_frame *xdpf,
> struct xdp_bulk_queue *bq = this_cpu_ptr(obj->bulkq);
>
> if (unlikely(bq->count == DEV_MAP_BULK_SIZE))
> - bq_xmit_all(obj, bq);
> + bq_xmit_all(obj, bq, false);
>
> /* Ingress dev_rx will be the same for all xdp_frame's in
> * bulk_queue, because bq stored per-CPU and must be flushed
> @@ -359,8 +356,7 @@ static void *dev_map_lookup_elem(struct bpf_map *map,
> void *key)
>
> static void dev_map_flush_old(struct bpf_dtab_netdev *dev)
> {
> - if (dev->dev->netdev_ops->ndo_xdp_flush) {
> - struct net_device *fl = dev->dev;
> + if (dev->dev->netdev_ops->ndo_xdp_xmit) {
> struct xdp_bulk_queue *bq;
> unsigned long *bitmap;
>
> @@ -371,9 +367,7 @@ static void dev_map_flush_old(struct bpf_dtab_netdev *dev)
> __clear_bit(dev->bit, bitmap);
>
> bq = per_cpu_ptr(dev->bulkq, cpu);
> - bq_xmit_all(dev, bq);
> -
> - fl->netdev_ops->ndo_xdp_flush(dev->dev);
> + bq_xmit_all(dev, bq, true);
> }
> }
> }
>
