rps: Add flag to skb to indicate rxhash is based on L4 tuple
The l4_rxhash flag was added to the skb structure to indicate
that the rxhash value was computed over the 4 tuple for the
packet which includes the port information in the encapsulated
transport packet. This is used by the stack to preserve the
rxhash value in __skb_rx_tunnel.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 7b996ed..f902c33 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -414,6 +414,7 @@
__u8 ndisc_nodetype:2;
#endif
__u8 ooo_okay:1;
+ __u8 l4_rxhash:1;
kmemcheck_bitfield_end(flags2);
/* 0/13 bit hole */
@@ -572,11 +573,11 @@
unsigned int to, struct ts_config *config,
struct ts_state *state);
-extern __u32 __skb_get_rxhash(struct sk_buff *skb);
+extern void __skb_get_rxhash(struct sk_buff *skb);
static inline __u32 skb_get_rxhash(struct sk_buff *skb)
{
if (!skb->rxhash)
- skb->rxhash = __skb_get_rxhash(skb);
+ __skb_get_rxhash(skb);
return skb->rxhash;
}
diff --git a/include/net/dst.h b/include/net/dst.h
index 13d507d..4fb6c43 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -325,7 +325,14 @@
static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
{
skb->dev = dev;
- skb->rxhash = 0;
+
+ /*
+ * Clear rxhash so that we can recalulate the hash for the
+ * encapsulated packet, unless we have already determine the hash
+ * over the L4 4-tuple.
+ */
+ if (!skb->l4_rxhash)
+ skb->rxhash = 0;
skb_set_queue_mapping(skb, 0);
skb_dst_drop(skb);
nf_reset(skb);
diff --git a/include/net/sock.h b/include/net/sock.h
index 8e4062f..5ac682f 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -686,16 +686,25 @@
#endif
}
-static inline void sock_rps_save_rxhash(struct sock *sk, u32 rxhash)
+static inline void sock_rps_save_rxhash(struct sock *sk,
+ const struct sk_buff *skb)
{
#ifdef CONFIG_RPS
- if (unlikely(sk->sk_rxhash != rxhash)) {
+ if (unlikely(sk->sk_rxhash != skb->rxhash)) {
sock_rps_reset_flow(sk);
- sk->sk_rxhash = rxhash;
+ sk->sk_rxhash = skb->rxhash;
}
#endif
}
+static inline void sock_rps_reset_rxhash(struct sock *sk)
+{
+#ifdef CONFIG_RPS
+ sock_rps_reset_flow(sk);
+ sk->sk_rxhash = 0;
+#endif
+}
+
#define sk_wait_event(__sk, __timeo, __condition) \
({ int __rc; \
release_sock(__sk); \
diff --git a/net/core/dev.c b/net/core/dev.c
index 6578d94..e485cb3 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2519,10 +2519,11 @@
/*
* __skb_get_rxhash: calculate a flow hash based on src/dst addresses
- * and src/dst port numbers. Returns a non-zero hash number on success
- * and 0 on failure.
+ * and src/dst port numbers. Sets rxhash in skb to non-zero hash value
+ * on success, zero indicates no valid hash. Also, sets l4_rxhash in skb
+ * if hash is a canonical 4-tuple hash over transport ports.
*/
-__u32 __skb_get_rxhash(struct sk_buff *skb)
+void __skb_get_rxhash(struct sk_buff *skb)
{
int nhoff, hash = 0, poff;
const struct ipv6hdr *ip6;
@@ -2574,6 +2575,7 @@
ports.v32 = * (__force u32 *) (skb->data + nhoff);
if (ports.v16[1] < ports.v16[0])
swap(ports.v16[0], ports.v16[1]);
+ skb->l4_rxhash = 1;
}
}
@@ -2586,7 +2588,7 @@
hash = 1;
done:
- return hash;
+ skb->rxhash = hash;
}
EXPORT_SYMBOL(__skb_get_rxhash);
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 27002df..edb66f3 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -529,6 +529,7 @@
new->mac_header = old->mac_header;
skb_dst_copy(new, old);
new->rxhash = old->rxhash;
+ new->l4_rxhash = old->l4_rxhash;
#ifdef CONFIG_XFRM
new->sp = secpath_get(old->sp);
#endif
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 1c12b8e..b3f2611 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1578,7 +1578,7 @@
#endif
if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
- sock_rps_save_rxhash(sk, skb->rxhash);
+ sock_rps_save_rxhash(sk, skb);
if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len)) {
rsk = sk;
goto reset;
@@ -1595,7 +1595,7 @@
goto discard;
if (nsk != sk) {
- sock_rps_save_rxhash(nsk, skb->rxhash);
+ sock_rps_save_rxhash(nsk, skb);
if (tcp_child_process(sk, nsk, skb)) {
rsk = nsk;
goto reset;
@@ -1603,7 +1603,7 @@
return 0;
}
} else
- sock_rps_save_rxhash(sk, skb->rxhash);
+ sock_rps_save_rxhash(sk, skb);
if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) {
rsk = sk;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index c1d5fac..ebaa96b 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1267,7 +1267,7 @@
sk->sk_state = TCP_CLOSE;
inet->inet_daddr = 0;
inet->inet_dport = 0;
- sock_rps_save_rxhash(sk, 0);
+ sock_rps_reset_rxhash(sk);
sk->sk_bound_dev_if = 0;
if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
inet_reset_saddr(sk);
@@ -1355,7 +1355,7 @@
int rc;
if (inet_sk(sk)->inet_daddr)
- sock_rps_save_rxhash(sk, skb->rxhash);
+ sock_rps_save_rxhash(sk, skb);
rc = ip_queue_rcv_skb(sk, skb);
if (rc < 0) {
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index d1fb63f..44a5859 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1628,7 +1628,7 @@
opt_skb = skb_clone(skb, GFP_ATOMIC);
if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
- sock_rps_save_rxhash(sk, skb->rxhash);
+ sock_rps_save_rxhash(sk, skb);
if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len))
goto reset;
if (opt_skb)
@@ -1650,7 +1650,7 @@
* the new socket..
*/
if(nsk != sk) {
- sock_rps_save_rxhash(nsk, skb->rxhash);
+ sock_rps_save_rxhash(nsk, skb);
if (tcp_child_process(sk, nsk, skb))
goto reset;
if (opt_skb)
@@ -1658,7 +1658,7 @@
return 0;
}
} else
- sock_rps_save_rxhash(sk, skb->rxhash);
+ sock_rps_save_rxhash(sk, skb);
if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len))
goto reset;
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 97e47f0..35bbdc4 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -509,7 +509,7 @@
int is_udplite = IS_UDPLITE(sk);
if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
- sock_rps_save_rxhash(sk, skb->rxhash);
+ sock_rps_save_rxhash(sk, skb);
if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
goto drop;
