wil6210: prefetch head of packet

As soon as skb is ready to be reaped, prefetch 1-st cache line.
This accelerates data access that is performed later, during the
packet classification by the driver and IP stack.
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/wil6210/txrx.c

@@ -21,6 +21,7 @@
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <net/ipv6.h>
+#include <asm/processor.h>
 
 #include "wil6210.h"
 #include "wmi.h"
@@ -377,6 +378,8 @@ static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
 	}
 	skb_trim(skb, dmalen);
 
+	prefetch(skb->data);
+
 	wil_hex_dump_txrx("Rx ", DUMP_PREFIX_OFFSET, 16, 1,
 			  skb->data, skb_headlen(skb), false);