From: Jakub Kicinski Date: Thu, 13 Feb 2025 01:06:35 +0000 (-0800) Subject: eth: mlx4: use the page pool for Rx buffers X-Git-Tag: v6.15-rc1~160^2~293^2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=82b023c97f602970af6e1f77914cbba5f63b3936;p=thirdparty%2Flinux.git eth: mlx4: use the page pool for Rx buffers Simple conversion to page pool. Preserve the current fragmentation logic / page splitting. Each page starts with a single frag reference, and then we bump that when attaching to skbs. This can likely be optimized further. Reviewed-by: Tariq Toukan Link: https://patch.msgid.link/20250213010635.1354034-5-kuba@kernel.org Signed-off-by: Jakub Kicinski --- diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c index d2cfbf2e38d96..b33285d755b90 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c @@ -52,57 +52,39 @@ #include "mlx4_en.h" -static int mlx4_alloc_page(struct mlx4_en_priv *priv, - struct mlx4_en_rx_alloc *frag, - gfp_t gfp) -{ - struct page *page; - dma_addr_t dma; - - page = alloc_page(gfp); - if (unlikely(!page)) - return -ENOMEM; - dma = dma_map_page(priv->ddev, page, 0, PAGE_SIZE, priv->dma_dir); - if (unlikely(dma_mapping_error(priv->ddev, dma))) { - __free_page(page); - return -ENOMEM; - } - frag->page = page; - frag->dma = dma; - frag->page_offset = priv->rx_headroom; - return 0; -} - static int mlx4_en_alloc_frags(struct mlx4_en_priv *priv, struct mlx4_en_rx_ring *ring, struct mlx4_en_rx_desc *rx_desc, struct mlx4_en_rx_alloc *frags, gfp_t gfp) { + dma_addr_t dma; int i; for (i = 0; i < priv->num_frags; i++, frags++) { if (!frags->page) { - if (mlx4_alloc_page(priv, frags, gfp)) { + frags->page = page_pool_alloc_pages(ring->pp, gfp); + if (!frags->page) { ring->alloc_fail++; return -ENOMEM; } + page_pool_fragment_page(frags->page, 1); + frags->page_offset = priv->rx_headroom; + ring->rx_alloc_pages++; } - rx_desc->data[i].addr = cpu_to_be64(frags->dma + - frags->page_offset); + dma = page_pool_get_dma_addr(frags->page); + rx_desc->data[i].addr = cpu_to_be64(dma + frags->page_offset); } return 0; } static void mlx4_en_free_frag(const struct mlx4_en_priv *priv, + struct mlx4_en_rx_ring *ring, struct mlx4_en_rx_alloc *frag) { - if (frag->page) { - dma_unmap_page(priv->ddev, frag->dma, - PAGE_SIZE, priv->dma_dir); - __free_page(frag->page); - } + if (frag->page) + page_pool_put_full_page(ring->pp, frag->page, false); /* We need to clear all fields, otherwise a change of priv->log_rx_info * could lead to see garbage later in frag->page. */ @@ -167,7 +149,7 @@ static void mlx4_en_free_rx_desc(const struct mlx4_en_priv *priv, frags = ring->rx_info + (index << priv->log_rx_info); for (nr = 0; nr < priv->num_frags; nr++) { en_dbg(DRV, priv, "Freeing fragment:%d\n", nr); - mlx4_en_free_frag(priv, frags + nr); + mlx4_en_free_frag(priv, ring, frags + nr); } } @@ -469,7 +451,7 @@ static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv, if (unlikely(!page)) goto fail; - dma = frags->dma; + dma = page_pool_get_dma_addr(page); dma_sync_single_range_for_cpu(priv->ddev, dma, frags->page_offset, frag_size, priv->dma_dir); @@ -480,6 +462,7 @@ static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv, if (frag_info->frag_stride == PAGE_SIZE / 2) { frags->page_offset ^= PAGE_SIZE / 2; release = page_count(page) != 1 || + atomic_long_read(&page->pp_ref_count) != 1 || page_is_pfmemalloc(page) || page_to_nid(page) != numa_mem_id(); } else if (!priv->rx_headroom) { @@ -493,10 +476,9 @@ static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv, release = frags->page_offset + frag_info->frag_size > PAGE_SIZE; } if (release) { - dma_unmap_page(priv->ddev, dma, PAGE_SIZE, priv->dma_dir); frags->page = NULL; } else { - page_ref_inc(page); + page_pool_ref_page(page); } nr++; @@ -766,7 +748,8 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud /* Get pointer to first fragment since we haven't * skb yet and cast it to ethhdr struct */ - dma = frags[0].dma + frags[0].page_offset; + dma = page_pool_get_dma_addr(frags[0].page); + dma += frags[0].page_offset; dma_sync_single_for_cpu(priv->ddev, dma, sizeof(*ethh), DMA_FROM_DEVICE); @@ -805,7 +788,8 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud void *orig_data; u32 act; - dma = frags[0].dma + frags[0].page_offset; + dma = page_pool_get_dma_addr(frags[0].page); + dma += frags[0].page_offset; dma_sync_single_for_cpu(priv->ddev, dma, priv->frag_info[0].frag_size, DMA_FROM_DEVICE); @@ -868,6 +852,7 @@ xdp_drop_no_cnt: skb = napi_get_frags(&cq->napi); if (unlikely(!skb)) goto next; + skb_mark_for_recycle(skb); if (unlikely(ring->hwtstamp_rx_filter == HWTSTAMP_FILTER_ALL)) { u64 timestamp = mlx4_en_get_cqe_ts(cqe); diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c index fe1378a689a10..87f35bcbeff8f 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c @@ -44,6 +44,7 @@ #include #include #include +#include #include "mlx4_en.h" @@ -350,9 +351,10 @@ 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 page_pool *pool = ring->recycle_ring->pp; - dma_unmap_page(priv->ddev, tx_info->map0_dma, PAGE_SIZE, priv->dma_dir); - put_page(tx_info->page); + /* Note that napi_mode = 0 means ndo_close() path, not budget = 0 */ + page_pool_put_full_page(pool, tx_info->page, !!napi_mode); return tx_info->nr_txbb; } @@ -1189,7 +1191,7 @@ netdev_tx_t mlx4_en_xmit_frame(struct mlx4_en_rx_ring *rx_ring, tx_desc = ring->buf + (index << LOG_TXBB_SIZE); data = &tx_desc->data; - dma = frame->dma; + dma = page_pool_get_dma_addr(frame->page); tx_info->page = frame->page; frame->page = NULL; diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h index 97311c98569f5..ad0d91a751848 100644 --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h @@ -247,7 +247,6 @@ struct mlx4_en_tx_desc { struct mlx4_en_rx_alloc { struct page *page; - dma_addr_t dma; u32 page_offset; };