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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Greg Kroah-Hartman , "Rafael J . Wysocki" , Danilo Krummrich , Jonathan Corbet , Jesper Dangaard Brouer , Ilias Apalodimas , Willem de Bruijn , Kuniyuki Iwashima , Joshua Washington , Harshitha Ramamurthy , Saeed Mahameed , Tariq Toukan , Tony Nguyen , Przemek Kitszel , Alexander Lobakin , Michael Chan , Pavan Chebbi , iommu@lists.linux.dev, netdev@vger.kernel.org, linux-mm@kvack.org, driver-core@lists.linux.dev, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Luigi Rizzo Content-Type: text/plain; charset="UTF-8" When dev->dma_pmd_tx_hdrs is enabled, allocate a MAX_TCP_HEADER bounce buffer per TX buffer slot out of the DMA_PMD arena. When the linear portion of a transmitted packet is at most MAX_TCP_HEADER bytes, copy it into the pre-mapped bounce buffer and set the SQE unmap length to 0 instead of calling dma_map_single()/dma_unmap_page() on every packet. Signed-off-by: Luigi Rizzo --- .../ethernet/intel/idpf/idpf_singleq_txrx.c | 6 ++--- drivers/net/ethernet/intel/idpf/idpf_txrx.c | 21 ++++++++++++--- drivers/net/ethernet/intel/idpf/idpf_txrx.h | 27 ++++++++++++++++++- include/net/libeth/tx.h | 5 ++-- 4 files changed, 50 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c index e3ddf18dcbf51..24a2dfec6212d 100644 --- a/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c +++ b/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c @@ -261,7 +261,7 @@ static void idpf_tx_singleq_map(struct idpf_tx_queue *tx_q, tx_desc = &tx_q->base_tx[i]; - dma = dma_map_single(tx_q->dev, skb->data, size, DMA_TO_DEVICE); + dma = idpf_tx_map_hdr(tx_q, skb, first, size); /* write each descriptor with CRC bit */ if (idpf_queue_has(CRC_EN, tx_q)) @@ -274,8 +274,7 @@ static void idpf_tx_singleq_map(struct idpf_tx_queue *tx_q, return idpf_tx_singleq_dma_map_error(tx_q, skb, first, i); - /* record length, and DMA address */ - dma_unmap_len_set(tx_buf, len, size); + /* record DMA address */ dma_unmap_addr_set(tx_buf, dma, dma); tx_buf->type = LIBETH_SQE_FRAG; @@ -326,6 +325,7 @@ static void idpf_tx_singleq_map(struct idpf_tx_queue *tx_q, size = skb_frag_size(frag); data_len -= size; + dma_unmap_len_set(tx_buf, len, size); dma = skb_frag_dma_map(tx_q->dev, frag, 0, size, DMA_TO_DEVICE); diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c index 4311ffa30bb18..4bdec468ea2ce 100644 --- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c +++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c @@ -90,6 +90,14 @@ static void idpf_tx_buf_rel_all(struct idpf_tx_queue *txq) else idpf_tx_buf_clean(txq); + if (txq->hdr_buf_va) { + dma_free_coherent(txq->dev, + txq->buf_pool_size * MAX_TCP_HEADER, + txq->hdr_buf_va, txq->hdr_buf_dma); + txq->hdr_buf_va = NULL; + txq->hdr_buf_dma = 0; + } + kfree(txq->tx_buf); txq->tx_buf = NULL; } @@ -187,6 +195,13 @@ static int idpf_tx_buf_alloc_all(struct idpf_tx_queue *tx_q) if (!tx_q->tx_buf) return -ENOMEM; + if (tx_q->dev->dma_pmd_tx_hdrs) + tx_q->hdr_buf_va = + dma_alloc_coherent(tx_q->dev, + tx_q->buf_pool_size * MAX_TCP_HEADER, + &tx_q->hdr_buf_dma, + GFP_KERNEL | __GFP_NOWARN); + return 0; } @@ -2663,7 +2678,7 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q, tx_desc = &tx_q->flex_tx[i]; - dma = dma_map_single(tx_q->dev, skb->data, size, DMA_TO_DEVICE); + dma = idpf_tx_map_hdr(tx_q, skb, first, size); tx_buf = first; first->nr_frags = 0; @@ -2680,8 +2695,7 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q, first->nr_frags++; tx_buf->type = LIBETH_SQE_FRAG; - /* record length, and DMA address */ - dma_unmap_len_set(tx_buf, len, size); + /* record DMA address */ dma_unmap_addr_set(tx_buf, dma, dma); /* buf_addr is in same location for both desc types */ @@ -2784,6 +2798,7 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q, size = skb_frag_size(frag); data_len -= size; + dma_unmap_len_set(tx_buf, len, size); dma = skb_frag_dma_map(tx_q->dev, frag, 0, size, DMA_TO_DEVICE); diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.h b/drivers/net/ethernet/intel/idpf/idpf_txrx.h index 93547597efd2a..39458a8e5baa0 100644 --- a/drivers/net/ethernet/intel/idpf/idpf_txrx.h +++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.h @@ -8,6 +8,7 @@ #include #include +#include #include #include #include @@ -639,6 +640,8 @@ libeth_cacheline_set_assert(struct idpf_rx_queue, * @q_vector: Backreference to associated vector * @buf_pool_size: Total number of idpf_tx_buf * @rel_q_id: relative virtchnl queue index + * @hdr_buf_va: Base of the TX header bounce buffer array, or NULL + * @hdr_buf_dma: DMA address matching @hdr_buf_va */ struct idpf_tx_queue { __cacheline_group_begin_aligned(read_mostly); @@ -715,6 +718,8 @@ struct idpf_tx_queue { u32 buf_pool_size; u32 rel_q_id; + void *hdr_buf_va; + dma_addr_t hdr_buf_dma; __cacheline_group_end_aligned(cold); }; libeth_cacheline_set_assert(struct idpf_tx_queue, 64, @@ -723,7 +728,7 @@ libeth_cacheline_set_assert(struct idpf_tx_queue, 64, offsetofend(struct idpf_tx_queue, timer) + offsetof(struct idpf_tx_queue, q_stats) - offsetofend(struct idpf_tx_queue, tstamp_task), - 32); + 48); /** * struct idpf_buf_queue - software structure representing a buffer queue @@ -1131,4 +1136,24 @@ int idpf_tso(struct sk_buff *skb, struct idpf_tx_offload_params *off); void idpf_wait_for_sw_marker_completion(const struct idpf_tx_queue *txq); +static inline dma_addr_t idpf_tx_map_hdr(struct idpf_tx_queue *tx_q, + const struct sk_buff *skb, + struct libeth_sqe *first, + unsigned int size) +{ + u32 buf_idx = first - tx_q->tx_buf; + + if (tx_q->hdr_buf_va && buf_idx < tx_q->buf_pool_size && + size <= MAX_TCP_HEADER) { + u32 offset = buf_idx * MAX_TCP_HEADER; + + memcpy(tx_q->hdr_buf_va + offset, skb->data, size); + dma_unmap_len_set(first, len, 0); + return tx_q->hdr_buf_dma + offset; + } + + dma_unmap_len_set(first, len, size); + return dma_map_single(tx_q->dev, skb->data, size, DMA_TO_DEVICE); +} + #endif /* !_IDPF_TXRX_H_ */ diff --git a/include/net/libeth/tx.h b/include/net/libeth/tx.h index c3db5c6f16410..2720ab9393e90 100644 --- a/include/net/libeth/tx.h +++ b/include/net/libeth/tx.h @@ -130,8 +130,9 @@ static inline void libeth_tx_complete(struct libeth_sqe *sqe, case LIBETH_SQE_SKB: case LIBETH_SQE_FRAG: case LIBETH_SQE_SLAB: - dma_unmap_page(cp->dev, dma_unmap_addr(sqe, dma), - dma_unmap_len(sqe, len), DMA_TO_DEVICE); + if (dma_unmap_len(sqe, len)) + dma_unmap_page(cp->dev, dma_unmap_addr(sqe, dma), + dma_unmap_len(sqe, len), DMA_TO_DEVICE); break; default: break; -- 2.56.0.rc1.315.gc6ed9934b7-goog