net: Pre-COW metrics for TCP.
TCP is going to record metrics for the connection,
so pre-COW the route metrics at route cache entry
creation time.
This avoids several atomic operations that have to
occur if we COW the metrics after the entry reaches
global visibility.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/flow.h b/include/net/flow.h
index 240b7f3..1ae901f 100644
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -48,7 +48,8 @@
__u8 proto;
__u8 flags;
-#define FLOWI_FLAG_ANYSRC 0x01
+#define FLOWI_FLAG_ANYSRC 0x01
+#define FLOWI_FLAG_PRECOW_METRICS 0x02
union {
struct {
__be16 sport;
diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 8181498..6e6dfd7 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -219,7 +219,13 @@
static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
{
- return inet_sk(sk)->transparent ? FLOWI_FLAG_ANYSRC : 0;
+ __u8 flags = 0;
+
+ if (inet_sk(sk)->transparent)
+ flags |= FLOWI_FLAG_ANYSRC;
+ if (sk->sk_protocol == IPPROTO_TCP)
+ flags |= FLOWI_FLAG_PRECOW_METRICS;
+ return flags;
}
#endif /* _INET_SOCK_H */
diff --git a/include/net/route.h b/include/net/route.h
index 5677cbf..e586465 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -182,6 +182,8 @@
if (inet_sk(sk)->transparent)
fl.flags |= FLOWI_FLAG_ANYSRC;
+ if (protocol == IPPROTO_TCP)
+ fl.flags |= FLOWI_FLAG_PRECOW_METRICS;
if (!dst || !src) {
err = __ip_route_output_key(net, rp, &fl);
@@ -209,6 +211,8 @@
fl.proto = protocol;
if (inet_sk(sk)->transparent)
fl.flags |= FLOWI_FLAG_ANYSRC;
+ if (protocol == IPPROTO_TCP)
+ fl.flags |= FLOWI_FLAG_PRECOW_METRICS;
ip_rt_put(*rp);
*rp = NULL;
security_sk_classify_flow(sk, &fl);