eth: mlx4: remove the local XDP fast-recycling ring

It will be replaced with page pool's built-in recycling.

Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250213010635.1354034-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index a8c0cf5..d2cfbf2 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -142,18 +142,6 @@ static int mlx4_en_prepare_rx_desc(struct mlx4_en_priv *priv,
                (index << ring->log_stride);
        struct mlx4_en_rx_alloc *frags = ring->rx_info +
                                        (index << priv->log_rx_info);
-       if (likely(ring->page_cache.index > 0)) {
-               /* XDP uses a single page per frame */
-               if (!frags->page) {
-                       ring->page_cache.index--;
-                       frags->page = ring->page_cache.buf[ring->page_cache.index].page;
-                       frags->dma  = ring->page_cache.buf[ring->page_cache.index].dma;
-               }
-               frags->page_offset = XDP_PACKET_HEADROOM;
-               rx_desc->data[0].addr = cpu_to_be64(frags->dma +
-                                                   XDP_PACKET_HEADROOM);
-               return 0;
-       }
 
        return mlx4_en_alloc_frags(priv, ring, rx_desc, frags, gfp);
 }
@@ -430,26 +418,6 @@ void mlx4_en_recover_from_oom(struct mlx4_en_priv *priv)
        }
 }
 
-/* When the rx ring is running in page-per-packet mode, a released frame can go
- * directly into a small cache, to avoid unmapping or touching the page
- * allocator. In bpf prog performance scenarios, buffers are either forwarded
- * or dropped, never converted to skbs, so every page can come directly from
- * this cache when it is sized to be a multiple of the napi budget.
- */
-bool mlx4_en_rx_recycle(struct mlx4_en_rx_ring *ring,
-                       struct mlx4_en_rx_alloc *frame)
-{
-       struct mlx4_en_page_cache *cache = &ring->page_cache;
-
-       if (cache->index >= MLX4_EN_CACHE_SIZE)
-               return false;
-
-       cache->buf[cache->index].page = frame->page;
-       cache->buf[cache->index].dma = frame->dma;
-       cache->index++;
-       return true;
-}
-
 void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
                             struct mlx4_en_rx_ring **pring,
                             u32 size, u16 stride)
@@ -475,14 +443,6 @@ void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
 void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
                                struct mlx4_en_rx_ring *ring)
 {
-       int i;
-
-       for (i = 0; i < ring->page_cache.index; i++) {
-               dma_unmap_page(priv->ddev, ring->page_cache.buf[i].dma,
-                              PAGE_SIZE, priv->dma_dir);
-               put_page(ring->page_cache.buf[i].page);
-       }
-       ring->page_cache.index = 0;
        mlx4_en_free_rx_buf(priv, ring);
        if (ring->stride <= TXBB_SIZE)
                ring->buf -= TXBB_SIZE;

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index 6e077d2..fe1378a 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -350,16 +350,9 @@ u32 mlx4_en_recycle_tx_desc(struct mlx4_en_priv *priv,
                            int napi_mode)
 {
        struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
-       struct mlx4_en_rx_alloc frame = {
-               .page = tx_info->page,
-               .dma = tx_info->map0_dma,
-       };
-
-       if (!napi_mode || !mlx4_en_rx_recycle(ring->recycle_ring, &frame)) {
-               dma_unmap_page(priv->ddev, tx_info->map0_dma,
-                              PAGE_SIZE, priv->dma_dir);
-               put_page(tx_info->page);
-       }
+
+       dma_unmap_page(priv->ddev, tx_info->map0_dma, PAGE_SIZE, priv->dma_dir);
+       put_page(tx_info->page);
 
        return tx_info->nr_txbb;
 }

diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index 29f48e6..97311c9 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -253,14 +253,6 @@ struct mlx4_en_rx_alloc {
 
 #define MLX4_EN_CACHE_SIZE (2 * NAPI_POLL_WEIGHT)
 
-struct mlx4_en_page_cache {
-       u32 index;
-       struct {
-               struct page     *page;
-               dma_addr_t      dma;
-       } buf[MLX4_EN_CACHE_SIZE];
-};
-
 enum {
        MLX4_EN_TX_RING_STATE_RECOVERING,
 };
@@ -343,7 +335,6 @@ struct mlx4_en_rx_ring {
        void *buf;
        void *rx_info;
        struct bpf_prog __rcu *xdp_prog;
-       struct mlx4_en_page_cache page_cache;
        unsigned long bytes;
        unsigned long packets;
        unsigned long csum_ok;
@@ -708,8 +699,6 @@ netdev_tx_t mlx4_en_xmit_frame(struct mlx4_en_rx_ring *rx_ring,
                               struct mlx4_en_priv *priv, unsigned int length,
                               int tx_ind, bool *doorbell_pending);
 void mlx4_en_xmit_doorbell(struct mlx4_en_tx_ring *ring);
-bool mlx4_en_rx_recycle(struct mlx4_en_rx_ring *ring,
-                       struct mlx4_en_rx_alloc *frame);
 
 int mlx4_en_create_tx_ring(struct mlx4_en_priv *priv,
                           struct mlx4_en_tx_ring **pring,