X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fnet%2Fxen-netfront.c;h=7ffa43bd7cf9e9f3b1fc43f83d0ec4c53b355765;hb=e91d1694d362f065c51eb07b46b19e8b33c92777;hp=c26e28b4bd9f985a4d7c6d3307d969bb671bf6f7;hpb=58890c06691462ca29900d1116b28c7a3e131252;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index c26e28b4bd9f..7ffa43bd7cf9 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1015,29 +1015,10 @@ err:
 		i = xennet_fill_frags(np, skb, &tmpq);
 
 		/*
-		 * Truesize approximates the size of true data plus
-		 * any supervisor overheads. Adding hypervisor
-		 * overheads has been shown to significantly reduce
-		 * achievable bandwidth with the default receive
-		 * buffer size. It is therefore not wise to account
-		 * for it here.
-		 *
-		 * After alloc_skb(RX_COPY_THRESHOLD), truesize is set
-		 * to RX_COPY_THRESHOLD + the supervisor
-		 * overheads. Here, we add the size of the data pulled
-		 * in xennet_fill_frags().
-		 *
-		 * We also adjust for any unused space in the main
-		 * data area by subtracting (RX_COPY_THRESHOLD -
-		 * len). This is especially important with drivers
-		 * which split incoming packets into header and data,
-		 * using only 66 bytes of the main data area (see the
-		 * e1000 driver for example.)  On such systems,
-		 * without this last adjustement, our achievable
-		 * receive throughout using the standard receive
-		 * buffer size was cut by 25%(!!!).
-		 */
-		skb->truesize += skb->data_len - RX_COPY_THRESHOLD;
+                 * Truesize is the actual allocation size, even if the
+                 * allocation is only partially used.
+                 */
+		skb->truesize += PAGE_SIZE * skb_shinfo(skb)->nr_frags;
 		skb->len += skb->data_len;
 
 		if (rx->flags & XEN_NETRXF_csum_blank)