mlx5, xsk: Migrate to new MEM_TYPE_XSK_BUFF_POOL

Use the new MEM_TYPE_XSK_BUFF_POOL API in lieu of MEM_TYPE_ZERO_COPY in
mlx5e. It allows to drop a lot of code from the driver (which is now
common in AF_XDP core and was related to XSK RX frame allocation, DMA
mapping, etc.) and slightly improve performance (RX +0.8 Mpps, TX +0.4
Mpps).

rfc->v1: Put back the sanity check for XSK params, use XSK API to get
         the total headroom size. (Maxim)

v1->v2: Fix DMA address handling, set XDP metadata to invalid. (Maxim)

v2->v3: Handle frame_sz, use xsk_buff_xdp_get_frame_dma, use xsk_buff
        API for DMA sync on TX, add performance numbers. (Maxim)

v3->v4: Remove unused variable num_xsk_frames. (Jakub)

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200520192103.355233-12-bjorn.topel@gmail.com

1 files changed, 6 insertions, 43 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/umem.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/umem.c
index 5e49fdb564b3..7b17fcd0a56d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/umem.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/umem.c
@@ -10,40 +10,14 @@ static int mlx5e_xsk_map_umem(struct mlx5e_priv *priv,
 			      struct xdp_umem *umem)
 {
 	struct device *dev = priv->mdev->device;
-	u32 i;
 
-	for (i = 0; i < umem->npgs; i++) {
-		dma_addr_t dma = dma_map_page(dev, umem->pgs[i], 0, PAGE_SIZE,
-					      DMA_BIDIRECTIONAL);
-
-		if (unlikely(dma_mapping_error(dev, dma)))
-			goto err_unmap;
-		umem->pages[i].dma = dma;
-	}
-
-	return 0;
-
-err_unmap:
-	while (i--) {
-		dma_unmap_page(dev, umem->pages[i].dma, PAGE_SIZE,
-			       DMA_BIDIRECTIONAL);
-		umem->pages[i].dma = 0;
-	}
-
-	return -ENOMEM;
+	return xsk_buff_dma_map(umem, dev, 0);
 }
 
 static void mlx5e_xsk_unmap_umem(struct mlx5e_priv *priv,
 				 struct xdp_umem *umem)
 {
-	struct device *dev = priv->mdev->device;
-	u32 i;
-
-	for (i = 0; i < umem->npgs; i++) {
-		dma_unmap_page(dev, umem->pages[i].dma, PAGE_SIZE,
-			       DMA_BIDIRECTIONAL);
-		umem->pages[i].dma = 0;
-	}
+	return xsk_buff_dma_unmap(umem, 0);
 }
 
 static int mlx5e_xsk_get_umems(struct mlx5e_xsk *xsk)
@@ -90,13 +64,14 @@ static void mlx5e_xsk_remove_umem(struct mlx5e_xsk *xsk, u16 ix)
 
 static bool mlx5e_xsk_is_umem_sane(struct xdp_umem *umem)
 {
-	return umem->headroom <= 0xffff && umem->chunk_size_nohr <= 0xffff;
+	return xsk_umem_get_headroom(umem) <= 0xffff &&
+		xsk_umem_get_chunk_size(umem) <= 0xffff;
 }
 
 void mlx5e_build_xsk_param(struct xdp_umem *umem, struct mlx5e_xsk_param *xsk)
 {
-	xsk->headroom = umem->headroom;
-	xsk->chunk_size = umem->chunk_size_nohr + umem->headroom;
+	xsk->headroom = xsk_umem_get_headroom(umem);
+	xsk->chunk_size = xsk_umem_get_chunk_size(umem);
 }
 
 static int mlx5e_xsk_enable_locked(struct mlx5e_priv *priv,
@@ -241,18 +216,6 @@ int mlx5e_xsk_setup_umem(struct net_device *dev, struct xdp_umem *umem, u16 qid)
 		      mlx5e_xsk_disable_umem(priv, ix);
 }
 
-int mlx5e_xsk_resize_reuseq(struct xdp_umem *umem, u32 nentries)
-{
-	struct xdp_umem_fq_reuse *reuseq;
-
-	reuseq = xsk_reuseq_prepare(nentries);
-	if (unlikely(!reuseq))
-		return -ENOMEM;
-	xsk_reuseq_free(xsk_reuseq_swap(umem, reuseq));
-
-	return 0;
-}
-
 u16 mlx5e_xsk_first_unused_channel(struct mlx5e_params *params, struct mlx5e_xsk *xsk)
 {
 	u16 res = xsk->refcnt ? params->num_channels : 0;