Merge branch 'net-minor-cleanups-and-optimizations'

Alexander Duyck says:

====================
A couple of minor clean-ups and optimizations

This patch series is basically just a v2 of a couple patches I recently
submitted.

The two patches aren't technically related but there are just items I found
while cleaning up and prepping some further work to enable Tx checksums for
tunnels.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/geneve.c

@@ -463,8 +463,6 @@ static struct sk_buff **geneve_gro_receive(struct sk_buff **head,
 			goto out;
 	}
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		if (!NAPI_GRO_CB(p)->same_flow)
 			continue;
@@ -481,14 +479,13 @@ static struct sk_buff **geneve_gro_receive(struct sk_buff **head,
 
 	rcu_read_lock();
 	ptype = gro_find_receive_by_type(type);
-	if (!ptype) {
-		flush = 1;
+	if (!ptype)
 		goto out_unlock;
-	}
 
 	skb_gro_pull(skb, gh_len);
 	skb_gro_postpull_rcsum(skb, gh, gh_len);
 	pp = ptype->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();

drivers/net/vxlan.c

@@ -591,8 +591,6 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head,
 
 	skb_gro_pull(skb, sizeof(struct vxlanhdr)); /* pull vxlan header */
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		if (!NAPI_GRO_CB(p)->same_flow)
 			continue;
@@ -606,6 +604,7 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head,
 	}
 
 	pp = eth_gro_receive(head, skb);
+	flush = 0;
 
 out:
 	skb_gro_remcsum_cleanup(skb, &grc);

include/net/checksum.h

@@ -88,8 +88,11 @@ static inline __wsum
 csum_block_add(__wsum csum, __wsum csum2, int offset)
 {
 	u32 sum = (__force u32)csum2;
-	if (offset&1)
-		sum = ((sum&0xFF00FF)<<8)+((sum>>8)&0xFF00FF);
+
+	/* rotate sum to align it with a 16b boundary */
+	if (offset & 1)
+		sum = ror32(sum, 8);
+
 	return csum_add(csum, (__force __wsum)sum);
 }
 
@@ -102,10 +105,7 @@ csum_block_add_ext(__wsum csum, __wsum csum2, int offset, int len)
 static inline __wsum
 csum_block_sub(__wsum csum, __wsum csum2, int offset)
 {
-	u32 sum = (__force u32)csum2;
-	if (offset&1)
-		sum = ((sum&0xFF00FF)<<8)+((sum>>8)&0xFF00FF);
-	return csum_sub(csum, (__force __wsum)sum);
+	return csum_block_add(csum, ~csum2, offset);
 }
 
 static inline __wsum csum_unfold(__sum16 n)

net/ipv4/fou.c

@@ -319,8 +319,6 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
 
 	skb_gro_pull(skb, hdrlen);
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		const struct guehdr *guehdr2;
 
@@ -352,6 +350,7 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
 		goto out_unlock;
 
 	pp = ops->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();

net/ipv4/gre_offload.c

@@ -175,8 +175,6 @@ static struct sk_buff **gre_gro_receive(struct sk_buff **head,
 					     null_compute_pseudo);
 	}
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		const struct gre_base_hdr *greh2;
 
@@ -213,6 +211,7 @@ static struct sk_buff **gre_gro_receive(struct sk_buff **head,
 	skb_gro_postpull_rcsum(skb, greh, grehlen);
 
 	pp = ptype->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();