From: Tariq Toukan <tariqt@mellanox.com>
Date: Thu, 24 May 2018 13:44:24 +0300
Subject: net/mlx5e: TX, Obsolete maintaining local copies of skb->len/data
Patch-mainline: v4.18-rc1
Git-commit: 5e7d77a9c5738457cdaa6bc230799c8f80733481
References: bsc#1103990 FATE#326006

Instead of maintaining a local copy of skb->len/data and updating
it upon every copy to the WQE inline part, just calculate it once
when needed, using the ihs.

This obsoletes the function mlx5e_tx_skb_pull_inline.

Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_tx.c |   42 ++++++------------------
 1 file changed, 12 insertions(+), 30 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -188,28 +188,16 @@ static inline u16 mlx5e_calc_min_inline(
 	return min_t(u16, hlen, skb_headlen(skb));
 }
 
-static inline void mlx5e_tx_skb_pull_inline(unsigned char **skb_data,
-					    unsigned int *skb_len,
-					    unsigned int len)
-{
-	*skb_len -= len;
-	*skb_data += len;
-}
-
-static inline void mlx5e_insert_vlan(void *start, struct sk_buff *skb, u16 ihs,
-				     unsigned char **skb_data,
-				     unsigned int *skb_len)
+static inline void mlx5e_insert_vlan(void *start, struct sk_buff *skb, u16 ihs)
 {
 	struct vlan_ethhdr *vhdr = (struct vlan_ethhdr *)start;
 	int cpy1_sz = 2 * ETH_ALEN;
 	int cpy2_sz = ihs - cpy1_sz;
 
-	memcpy(vhdr, *skb_data, cpy1_sz);
-	mlx5e_tx_skb_pull_inline(skb_data, skb_len, cpy1_sz);
+	memcpy(vhdr, skb->data, cpy1_sz);
 	vhdr->h_vlan_proto = skb->vlan_proto;
 	vhdr->h_vlan_TCI = cpu_to_be16(skb_vlan_tag_get(skb));
-	memcpy(&vhdr->h_vlan_encapsulated_proto, *skb_data, cpy2_sz);
-	mlx5e_tx_skb_pull_inline(skb_data, skb_len, cpy2_sz);
+	memcpy(&vhdr->h_vlan_encapsulated_proto, skb->data + cpy1_sz, cpy2_sz);
 }
 
 static inline void
@@ -357,8 +345,6 @@ netdev_tx_t mlx5e_sq_xmit(struct mlx5e_t
 	struct mlx5e_tx_wqe_info *wi;
 
 	struct mlx5e_sq_stats *stats = sq->stats;
-	unsigned char *skb_data = skb->data;
-	unsigned int skb_len = skb->len;
 	u16 ds_cnt, ds_cnt_inl = 0;
 	u16 headlen, ihs, frag_pi;
 	u8 num_wqebbs, opcode;
@@ -385,7 +371,7 @@ netdev_tx_t mlx5e_sq_xmit(struct mlx5e_t
 	stats->bytes     += num_bytes;
 	stats->xmit_more += skb->xmit_more;
 
-	headlen = skb_len - ihs - skb->data_len;
+	headlen = skb->len - ihs - skb->data_len;
 	ds_cnt += !!headlen;
 	ds_cnt += skb_shinfo(skb)->nr_frags;
 
@@ -414,15 +400,14 @@ netdev_tx_t mlx5e_sq_xmit(struct mlx5e_t
 	eseg->mss = mss;
 
 	if (ihs) {
+		eseg->inline_hdr.sz = cpu_to_be16(ihs);
 		if (skb_vlan_tag_present(skb)) {
-			mlx5e_insert_vlan(eseg->inline_hdr.start, skb,
-					  ihs - VLAN_HLEN, &skb_data, &skb_len);
+			ihs -= VLAN_HLEN;
+			mlx5e_insert_vlan(eseg->inline_hdr.start, skb, ihs);
 			stats->added_vlan_packets++;
 		} else {
-			memcpy(eseg->inline_hdr.start, skb_data, ihs);
-			mlx5e_tx_skb_pull_inline(&skb_data, &skb_len, ihs);
+			memcpy(eseg->inline_hdr.start, skb->data, ihs);
 		}
-		eseg->inline_hdr.sz = cpu_to_be16(ihs);
 		dseg += ds_cnt_inl;
 	} else if (skb_vlan_tag_present(skb)) {
 		eseg->insert.type = cpu_to_be16(MLX5_ETH_WQE_INSERT_VLAN);
@@ -432,7 +417,7 @@ netdev_tx_t mlx5e_sq_xmit(struct mlx5e_t
 		stats->added_vlan_packets++;
 	}
 
-	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb_data, headlen, dseg);
+	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + ihs, headlen, dseg);
 	if (unlikely(num_dma < 0))
 		goto err_drop;
 
@@ -644,8 +629,6 @@ netdev_tx_t mlx5i_sq_xmit(struct mlx5e_t
 	struct mlx5e_tx_wqe_info *wi;
 
 	struct mlx5e_sq_stats *stats = sq->stats;
-	unsigned char *skb_data = skb->data;
-	unsigned int skb_len = skb->len;
 	u16 headlen, ihs, pi, frag_pi;
 	u16 ds_cnt, ds_cnt_inl = 0;
 	u8 num_wqebbs, opcode;
@@ -672,7 +655,7 @@ netdev_tx_t mlx5i_sq_xmit(struct mlx5e_t
 	stats->bytes     += num_bytes;
 	stats->xmit_more += skb->xmit_more;
 
-	headlen = skb_len - ihs - skb->data_len;
+	headlen = skb->len - ihs - skb->data_len;
 	ds_cnt += !!headlen;
 	ds_cnt += skb_shinfo(skb)->nr_frags;
 
@@ -704,13 +687,12 @@ netdev_tx_t mlx5i_sq_xmit(struct mlx5e_t
 	eseg->mss = mss;
 
 	if (ihs) {
-		memcpy(eseg->inline_hdr.start, skb_data, ihs);
-		mlx5e_tx_skb_pull_inline(&skb_data, &skb_len, ihs);
+		memcpy(eseg->inline_hdr.start, skb->data, ihs);
 		eseg->inline_hdr.sz = cpu_to_be16(ihs);
 		dseg += ds_cnt_inl;
 	}
 
-	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb_data, headlen, dseg);
+	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + ihs, headlen, dseg);
 	if (unlikely(num_dma < 0))
 		goto err_drop;