Commit d1668f11 authored by Saeed Mahameed's avatar Saeed Mahameed Committed by Jakub Kicinski
Browse files

net/mlx5e: Convert over to netmem 



mlx5e_page_frag holds the physical page itself, to naturally support
zc page pools, remove physical page reference from mlx5 and replace it
with netmem_ref, to avoid internal handling in mlx5 for net_iov backed
pages.

SHAMPO can issue packets that are not split into header and data. These
packets will be dropped if the data part resides in a net_iov as the
driver can't read into this area.

No performance degradation observed.

Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
Signed-off-by: default avatarDragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: default avatarDragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: default avatarTariq Toukan <tariqt@nvidia.com>
Reviewed-by: default avatarMina Almasry <almasrymina@google.com>
Signed-off-by: default avatarMark Bloch <mbloch@nvidia.com>
Link: https://patch.msgid.link/20250616141441.1243044-9-mbloch@nvidia.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent e225d9bd

drivers/net/ethernet/mellanox/mlx5/core/en.h

+1 −1
Original line number Diff line number Diff line
@@ -553,7 +553,7 @@ struct mlx5e_icosq { 
} ____cacheline_aligned_in_smp;



struct mlx5e_frag_page {

	struct page *page;

	netmem_ref netmem;

	u16 frags;

};

drivers/net/ethernet/mellanox/mlx5/core/en_rx.c

+62 −43
Original line number Diff line number Diff line
@@ -273,33 +273,32 @@ static inline u32 mlx5e_decompress_cqes_start(struct mlx5e_rq *rq, 


#define MLX5E_PAGECNT_BIAS_MAX (PAGE_SIZE / 64)



static int mlx5e_page_alloc_fragmented(struct page_pool *pool,

static int mlx5e_page_alloc_fragmented(struct page_pool *pp,

				       struct mlx5e_frag_page *frag_page)

{

	struct page *page;

	netmem_ref netmem = page_pool_dev_alloc_netmems(pp);



	page = page_pool_dev_alloc_pages(pool);

	if (unlikely(!page))

	if (unlikely(!netmem))

		return -ENOMEM;



	page_pool_fragment_page(page, MLX5E_PAGECNT_BIAS_MAX);

	page_pool_fragment_netmem(netmem, MLX5E_PAGECNT_BIAS_MAX);



	*frag_page = (struct mlx5e_frag_page) {

		.page	= page,

		.netmem	= netmem,

		.frags	= 0,

	};



	return 0;

}



static void mlx5e_page_release_fragmented(struct page_pool *pool,

static void mlx5e_page_release_fragmented(struct page_pool *pp,

					  struct mlx5e_frag_page *frag_page)

{

	u16 drain_count = MLX5E_PAGECNT_BIAS_MAX - frag_page->frags;

	struct page *page = frag_page->page;

	netmem_ref netmem = frag_page->netmem;



	if (page_pool_unref_page(page, drain_count) == 0)

		page_pool_put_unrefed_page(pool, page, -1, true);

	if (page_pool_unref_netmem(netmem, drain_count) == 0)

		page_pool_put_unrefed_netmem(pp, netmem, -1, true);

}



static inline int mlx5e_get_rx_frag(struct mlx5e_rq *rq,
@@ -359,7 +358,7 @@ static int mlx5e_alloc_rx_wqe(struct mlx5e_rq *rq, struct mlx5e_rx_wqe_cyc *wqe, 
		frag->flags &= ~BIT(MLX5E_WQE_FRAG_SKIP_RELEASE);



		headroom = i == 0 ? rq->buff.headroom : 0;

		addr = page_pool_get_dma_addr(frag->frag_page->page);

		addr = page_pool_get_dma_addr_netmem(frag->frag_page->netmem);

		wqe->data[i].addr = cpu_to_be64(addr + frag->offset + headroom);

	}
@@ -500,9 +499,10 @@ mlx5e_add_skb_shared_info_frag(struct mlx5e_rq *rq, struct skb_shared_info *sinf 
			       struct xdp_buff *xdp, struct mlx5e_frag_page *frag_page,

			       u32 frag_offset, u32 len)

{

	netmem_ref netmem = frag_page->netmem;

	skb_frag_t *frag;



	dma_addr_t addr = page_pool_get_dma_addr(frag_page->page);

	dma_addr_t addr = page_pool_get_dma_addr_netmem(netmem);



	dma_sync_single_for_cpu(rq->pdev, addr + frag_offset, len, rq->buff.map_dir);

	if (!xdp_buff_has_frags(xdp)) {
@@ -515,9 +515,9 @@ mlx5e_add_skb_shared_info_frag(struct mlx5e_rq *rq, struct skb_shared_info *sinf 
	}



	frag = &sinfo->frags[sinfo->nr_frags++];

	skb_frag_fill_page_desc(frag, frag_page->page, frag_offset, len);

	skb_frag_fill_netmem_desc(frag, netmem, frag_offset, len);



	if (page_is_pfmemalloc(frag_page->page))

	if (netmem_is_pfmemalloc(netmem))

		xdp_buff_set_frag_pfmemalloc(xdp);

	sinfo->xdp_frags_size += len;

}
@@ -528,27 +528,29 @@ mlx5e_add_skb_frag(struct mlx5e_rq *rq, struct sk_buff *skb, 
		   u32 frag_offset, u32 len,

		   unsigned int truesize)

{

	dma_addr_t addr = page_pool_get_dma_addr(frag_page->page);

	dma_addr_t addr = page_pool_get_dma_addr_netmem(frag_page->netmem);

	u8 next_frag = skb_shinfo(skb)->nr_frags;

	netmem_ref netmem = frag_page->netmem;



	dma_sync_single_for_cpu(rq->pdev, addr + frag_offset, len,

				rq->buff.map_dir);



	if (skb_can_coalesce(skb, next_frag, frag_page->page, frag_offset)) {

	if (skb_can_coalesce_netmem(skb, next_frag, netmem, frag_offset)) {

		skb_coalesce_rx_frag(skb, next_frag - 1, len, truesize);

	} else {

		return;

	}



	frag_page->frags++;

		skb_add_rx_frag(skb, next_frag, frag_page->page,

	skb_add_rx_frag_netmem(skb, next_frag, netmem,

			       frag_offset, len, truesize);

}

}



static inline void

mlx5e_copy_skb_header(struct mlx5e_rq *rq, struct sk_buff *skb,

		      struct page *page, dma_addr_t addr,

		      netmem_ref netmem, dma_addr_t addr,

		      int offset_from, int dma_offset, u32 headlen)

{

	const void *from = page_address(page) + offset_from;

	const void *from = netmem_address(netmem) + offset_from;

	/* Aligning len to sizeof(long) optimizes memcpy performance */

	unsigned int len = ALIGN(headlen, sizeof(long));
@@ -685,7 +687,7 @@ static int mlx5e_build_shampo_hd_umr(struct mlx5e_rq *rq, 
		if (unlikely(err))

			goto err_unmap;



		addr = page_pool_get_dma_addr(frag_page->page);

		addr = page_pool_get_dma_addr_netmem(frag_page->netmem);



		for (int j = 0; j < MLX5E_SHAMPO_WQ_HEADER_PER_PAGE; j++) {

			header_offset = mlx5e_shampo_hd_offset(index++);
@@ -796,7 +798,8 @@ static int mlx5e_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix) 
		err = mlx5e_page_alloc_fragmented(rq->page_pool, frag_page);

		if (unlikely(err))

			goto err_unmap;

		addr = page_pool_get_dma_addr(frag_page->page);



		addr = page_pool_get_dma_addr_netmem(frag_page->netmem);

		umr_wqe->inline_mtts[i] = (struct mlx5_mtt) {

			.ptag = cpu_to_be64(addr | MLX5_EN_WR),

		};
@@ -1216,7 +1219,7 @@ static void *mlx5e_shampo_get_packet_hd(struct mlx5e_rq *rq, u16 header_index) 
	struct mlx5e_frag_page *frag_page = mlx5e_shampo_hd_to_frag_page(rq, header_index);

	u16 head_offset = mlx5e_shampo_hd_offset(header_index) + rq->buff.headroom;



	return page_address(frag_page->page) + head_offset;

	return netmem_address(frag_page->netmem) + head_offset;

}



static void mlx5e_shampo_update_ipv4_udp_hdr(struct mlx5e_rq *rq, struct iphdr *ipv4)
@@ -1677,11 +1680,11 @@ mlx5e_skb_from_cqe_linear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi, 
	dma_addr_t addr;

	u32 frag_size;



	va             = page_address(frag_page->page) + wi->offset;

	va             = netmem_address(frag_page->netmem) + wi->offset;

	data           = va + rx_headroom;

	frag_size      = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt);



	addr = page_pool_get_dma_addr(frag_page->page);

	addr = page_pool_get_dma_addr_netmem(frag_page->netmem);

	dma_sync_single_range_for_cpu(rq->pdev, addr, wi->offset,

				      frag_size, rq->buff.map_dir);

	net_prefetch(data);
@@ -1731,10 +1734,10 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi 


	frag_page = wi->frag_page;



	va = page_address(frag_page->page) + wi->offset;

	va = netmem_address(frag_page->netmem) + wi->offset;

	frag_consumed_bytes = min_t(u32, frag_info->frag_size, cqe_bcnt);



	addr = page_pool_get_dma_addr(frag_page->page);

	addr = page_pool_get_dma_addr_netmem(frag_page->netmem);

	dma_sync_single_range_for_cpu(rq->pdev, addr, wi->offset,

				      rq->buff.frame0_sz, rq->buff.map_dir);

	net_prefetchw(va); /* xdp_frame data area */
@@ -2007,13 +2010,14 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w 


	if (prog) {

		/* area for bpf_xdp_[store|load]_bytes */

		net_prefetchw(page_address(frag_page->page) + frag_offset);

		net_prefetchw(netmem_address(frag_page->netmem) + frag_offset);

		if (unlikely(mlx5e_page_alloc_fragmented(rq->page_pool,

							 &wi->linear_page))) {

			rq->stats->buff_alloc_err++;

			return NULL;

		}

		va = page_address(wi->linear_page.page);



		va = netmem_address(wi->linear_page.netmem);

		net_prefetchw(va); /* xdp_frame data area */

		linear_hr = XDP_PACKET_HEADROOM;

		linear_data_len = 0;
@@ -2124,8 +2128,8 @@ mlx5e_skb_from_cqe_mpwrq_nonlinear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *w 
			while (++pagep < frag_page);

		}

		/* copy header */

		addr = page_pool_get_dma_addr(head_page->page);

		mlx5e_copy_skb_header(rq, skb, head_page->page, addr,

		addr = page_pool_get_dma_addr_netmem(head_page->netmem);

		mlx5e_copy_skb_header(rq, skb, head_page->netmem, addr,

				      head_offset, head_offset, headlen);

		/* skb linear part was allocated with headlen and aligned to long */

		skb->tail += headlen;
@@ -2155,11 +2159,11 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi, 
		return NULL;

	}



	va             = page_address(frag_page->page) + head_offset;

	va             = netmem_address(frag_page->netmem) + head_offset;

	data           = va + rx_headroom;

	frag_size      = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt);



	addr = page_pool_get_dma_addr(frag_page->page);

	addr = page_pool_get_dma_addr_netmem(frag_page->netmem);

	dma_sync_single_range_for_cpu(rq->pdev, addr, head_offset,

				      frag_size, rq->buff.map_dir);

	net_prefetch(data);
@@ -2198,16 +2202,19 @@ mlx5e_skb_from_cqe_shampo(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi, 
			  struct mlx5_cqe64 *cqe, u16 header_index)

{

	struct mlx5e_frag_page *frag_page = mlx5e_shampo_hd_to_frag_page(rq, header_index);

	dma_addr_t page_dma_addr = page_pool_get_dma_addr(frag_page->page);

	u16 head_offset = mlx5e_shampo_hd_offset(header_index);

	dma_addr_t dma_addr = page_dma_addr + head_offset;

	u16 head_size = cqe->shampo.header_size;

	u16 rx_headroom = rq->buff.headroom;

	struct sk_buff *skb = NULL;

	dma_addr_t page_dma_addr;

	dma_addr_t dma_addr;

	void *hdr, *data;

	u32 frag_size;



	hdr		= page_address(frag_page->page) + head_offset;

	page_dma_addr = page_pool_get_dma_addr_netmem(frag_page->netmem);

	dma_addr = page_dma_addr + head_offset;



	hdr		= netmem_address(frag_page->netmem) + head_offset;

	data		= hdr + rx_headroom;

	frag_size	= MLX5_SKB_FRAG_SZ(rx_headroom + head_size);
@@ -2232,7 +2239,7 @@ mlx5e_skb_from_cqe_shampo(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi, 
		}



		net_prefetchw(skb->data);

		mlx5e_copy_skb_header(rq, skb, frag_page->page, dma_addr,

		mlx5e_copy_skb_header(rq, skb, frag_page->netmem, dma_addr,

				      head_offset + rx_headroom,

				      rx_headroom, head_size);

		/* skb linear part was allocated with headlen and aligned to long */
@@ -2326,11 +2333,23 @@ static void mlx5e_handle_rx_cqe_mpwrq_shampo(struct mlx5e_rq *rq, struct mlx5_cq 
	}



	if (!*skb) {

		if (likely(head_size))

		if (likely(head_size)) {

			*skb = mlx5e_skb_from_cqe_shampo(rq, wi, cqe, header_index);

		else

			*skb = mlx5e_skb_from_cqe_mpwrq_nonlinear(rq, wi, cqe, cqe_bcnt,

								  data_offset, page_idx);

		} else {

			struct mlx5e_frag_page *frag_page;



			frag_page = &wi->alloc_units.frag_pages[page_idx];

			/* Drop packets with header in unreadable data area to

			 * prevent the kernel from touching it.

			 */

			if (unlikely(netmem_is_net_iov(frag_page->netmem)))

				goto free_hd_entry;

			*skb = mlx5e_skb_from_cqe_mpwrq_nonlinear(rq, wi, cqe,

								  cqe_bcnt,

								  data_offset,

								  page_idx);

		}



		if (unlikely(!*skb))

			goto free_hd_entry;