tcp: bind() optimize port allocation

Port autoselection finds a port and then drop the lock,
then right after that, gets the hash bucket again and lock it.

Fix it to go direct.

Signed-off-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 4 deletions

diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index ecd19b5a7ee2..19d66cefd7d3 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -123,15 +123,13 @@ again:
                                                 smallest_size = tb->num_owners;
                                                 smallest_rover = rover;
                                                 if (atomic_read(&hashinfo->bsockets) > (high - low) + 1) {
-                                                        spin_unlock(&head->lock);
                                                         snum = smallest_rover;
-                                                        goto have_snum;
+                                                        goto tb_found;
                                                 }
                                         }
                                         if (!inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
-                                                spin_unlock(&head->lock);
                                                 snum = rover;
-                                                goto have_snum;
+                                                goto tb_found;
                                         }
                                         goto next;
                                 }