From: Flavio Leitner <fbl@redhat.com>
Date: Wed, 25 Jan 2012 08:34:52 +0000 (+0000)
Subject: tcp: bind() optimize port allocation
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=fddb7b5761f104f034a0e708ece756d9b2eb2cac;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

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>
---

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;
 				}