tcp: speedup SIOCINQ ioctl
SIOCINQ can use the lock_sock_fast() version to avoid double acquisition
of socket lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index b7c2f43..eace049 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -536,13 +536,14 @@
{
struct tcp_sock *tp = tcp_sk(sk);
int answ;
+ bool slow;
switch (cmd) {
case SIOCINQ:
if (sk->sk_state == TCP_LISTEN)
return -EINVAL;
- lock_sock(sk);
+ slow = lock_sock_fast(sk);
if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))
answ = 0;
else if (sock_flag(sk, SOCK_URGINLINE) ||
@@ -557,7 +558,7 @@
answ--;
} else
answ = tp->urg_seq - tp->copied_seq;
- release_sock(sk);
+ unlock_sock_fast(sk, slow);
break;
case SIOCATMARK:
answ = tp->urg_data && tp->urg_seq == tp->copied_seq;