inet: kill smallest_size and smallest_port

In inet_csk_get_port we seem to be using smallest_port to figure out where the
best place to look for a SO_REUSEPORT sk that matches with an existing set of
SO_REUSEPORT's.  However if we get to the logic

if (smallest_size != -1) {
	port = smallest_port;
	goto have_port;
}

we will do a useless search, because we would have already done the
inet_csk_bind_conflict for that port and it would have returned 1, otherwise we
would have gone to found_tb and succeeded.  Since this logic makes us do yet
another trip through inet_csk_bind_conflict for a port we know won't work just
delete this code and save us the time.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Josef Bacik 2017-01-17 07:51:03 -08:00 committed by David S. Miller
parent aa078842b7
commit b9470c2760
3 changed files with 4 additions and 26 deletions

View file

@ -80,7 +80,6 @@ struct inet_bind_bucket {
signed char fastreuse;
signed char fastreuseport;
kuid_t fastuid;
int num_owners;
struct hlist_node node;
struct hlist_head owners;
};

View file

@ -165,7 +165,6 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum)
bool reuse = sk->sk_reuse && sk->sk_state != TCP_LISTEN;
struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
int ret = 1, attempts = 5, port = snum;
int smallest_size = -1, smallest_port;
struct inet_bind_hashbucket *head;
struct net *net = sock_net(sk);
int i, low, high, attempt_half;
@ -175,7 +174,6 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum)
bool reuseport_ok = !!snum;
if (port) {
have_port:
head = &hinfo->bhash[inet_bhashfn(net, port,
hinfo->bhash_size)];
spin_lock_bh(&head->lock);
@ -209,8 +207,6 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum)
* We do the opposite to not pollute connect() users.
*/
offset |= 1U;
smallest_size = -1;
smallest_port = low; /* avoid compiler warning */
other_parity_scan:
port = low + offset;
@ -224,15 +220,6 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum)
spin_lock_bh(&head->lock);
inet_bind_bucket_for_each(tb, &head->chain)
if (net_eq(ib_net(tb), net) && tb->port == port) {
if (((tb->fastreuse > 0 && reuse) ||
(tb->fastreuseport > 0 &&
sk->sk_reuseport &&
!rcu_access_pointer(sk->sk_reuseport_cb) &&
uid_eq(tb->fastuid, uid))) &&
(tb->num_owners < smallest_size || smallest_size == -1)) {
smallest_size = tb->num_owners;
smallest_port = port;
}
if (!inet_csk_bind_conflict(sk, tb, false, reuseport_ok))
goto tb_found;
goto next_port;
@ -243,10 +230,6 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum)
cond_resched();
}
if (smallest_size != -1) {
port = smallest_port;
goto have_port;
}
offset--;
if (!(offset & 1))
goto other_parity_scan;
@ -268,19 +251,18 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum)
if (sk->sk_reuse == SK_FORCE_REUSE)
goto success;
if (((tb->fastreuse > 0 && reuse) ||
if ((tb->fastreuse > 0 && reuse) ||
(tb->fastreuseport > 0 &&
!rcu_access_pointer(sk->sk_reuseport_cb) &&
sk->sk_reuseport && uid_eq(tb->fastuid, uid))) &&
smallest_size == -1)
sk->sk_reuseport && uid_eq(tb->fastuid, uid)))
goto success;
if (inet_csk_bind_conflict(sk, tb, true, reuseport_ok)) {
if ((reuse ||
(tb->fastreuseport > 0 &&
sk->sk_reuseport &&
!rcu_access_pointer(sk->sk_reuseport_cb) &&
uid_eq(tb->fastuid, uid))) &&
!snum && smallest_size != -1 && --attempts >= 0) {
uid_eq(tb->fastuid, uid))) && !snum &&
--attempts >= 0) {
spin_unlock_bh(&head->lock);
goto again;
}

View file

@ -73,7 +73,6 @@ struct inet_bind_bucket *inet_bind_bucket_create(struct kmem_cache *cachep,
tb->port = snum;
tb->fastreuse = 0;
tb->fastreuseport = 0;
tb->num_owners = 0;
INIT_HLIST_HEAD(&tb->owners);
hlist_add_head(&tb->node, &head->chain);
}
@ -96,7 +95,6 @@ void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
{
inet_sk(sk)->inet_num = snum;
sk_add_bind_node(sk, &tb->owners);
tb->num_owners++;
inet_csk(sk)->icsk_bind_hash = tb;
}
@ -114,7 +112,6 @@ static void __inet_put_port(struct sock *sk)
spin_lock(&head->lock);
tb = inet_csk(sk)->icsk_bind_hash;
__sk_del_bind_node(sk);
tb->num_owners--;
inet_csk(sk)->icsk_bind_hash = NULL;
inet_sk(sk)->inet_num = 0;
inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb);