net: speedup sock_recv_ts_and_drops()

sock_recv_ts_and_drops() is fat and slow (~ 4% of cpu time on some
profiles)

We can test all socket flags at once to make fast path fast again.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 20 insertions, 3 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index d361c7769fe0..e1777db5b9ab 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1635,7 +1635,24 @@ sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
                 sk->sk_stamp = kt;
 }
 
-extern void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, struct sk_buff *skb);
+extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
+                                     struct sk_buff *skb);
+
+static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
+                                          struct sk_buff *skb)
+{
+#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL)                       | \
+                           (1UL << SOCK_RCVTSTAMP)                      | \
+                           (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)       | \
+                           (1UL << SOCK_TIMESTAMPING_SOFTWARE)          | \
+                           (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE)      | \
+                           (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
+
+        if (sk->sk_flags & FLAGS_TS_OR_DROPS)
+                __sock_recv_ts_and_drops(msg, sk, skb);
+        else
+                sk->sk_stamp = skb->tstamp;
+}
 
 /**
  * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
diff --git a/net/socket.c b/net/socket.c
index 9822081eab38..cb7c1f6c0d6e 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -655,13 +655,13 @@ inline void sock_recv_drops(struct msghdr *msg, struct sock *sk, struct sk_buff
                         sizeof(__u32), &skb->dropcount);
 }
 
-void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
+void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
         struct sk_buff *skb)
 {
         sock_recv_timestamp(msg, sk, skb);
         sock_recv_drops(msg, sk, skb);
 }
-EXPORT_SYMBOL_GPL(sock_recv_ts_and_drops);
+EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops);
 
 static inline int __sock_recvmsg_nosec(struct kiocb *iocb, struct socket *sock,
                                        struct msghdr *msg, size_t size, int flags)