net: mvpp2: Add xdp tx return bulking support

Convert mvpp2 driver to xdp_return_frame_bulk APIs.

XDP_REDIRECT (upstream codepath): 1.79Mpps
XDP_REDIRECT (upstream codepath + bulking APIs): 1.93Mpps
Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Matteo Croce <mcroce@microsoft.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/0b38c295e58e8ce251ef6b4e2187a2f457f9f7a3.1605267335.git.lorenzo@kernel.org

drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c

@@ -2440,8 +2440,13 @@ static void mvpp2_txq_bufs_free(struct mvpp2_port *port,
 				struct mvpp2_tx_queue *txq,
 				struct mvpp2_txq_pcpu *txq_pcpu, int num)
 {
+	struct xdp_frame_bulk bq;
 	int i;
 
+	xdp_frame_bulk_init(&bq);
+
+	rcu_read_lock(); /* need for xdp_return_frame_bulk */
+
 	for (i = 0; i < num; i++) {
 		struct mvpp2_txq_pcpu_buf *tx_buf =
 			txq_pcpu->buffs + txq_pcpu->txq_get_index;
@@ -2454,10 +2459,13 @@ static void mvpp2_txq_bufs_free(struct mvpp2_port *port,
 			dev_kfree_skb_any(tx_buf->skb);
 		else if (tx_buf->type == MVPP2_TYPE_XDP_TX ||
 			 tx_buf->type == MVPP2_TYPE_XDP_NDO)
-			xdp_return_frame(tx_buf->xdpf);
+			xdp_return_frame_bulk(tx_buf->xdpf, &bq);
 
 		mvpp2_txq_inc_get(txq_pcpu);
 	}
+	xdp_flush_frame_bulk(&bq);
+
+	rcu_read_unlock();
 }
 
 static inline struct mvpp2_rx_queue *mvpp2_get_rx_queue(struct mvpp2_port *port,