| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20220621171913.73401-7-kuniyu@amazon.com>
Date: Tue, 21 Jun 2022 10:19:13 -0700
From: Kuniyuki Iwashima <kuniyu@...zon.com>
To: "David S. Miller" <davem@...emloft.net>,
Eric Dumazet <edumazet@...gle.com>,
Jakub Kicinski <kuba@...nel.org>,
Paolo Abeni <pabeni@...hat.com>
CC: Amit Shah <aams@...zon.com>, Kuniyuki Iwashima <kuniyu@...zon.com>,
Kuniyuki Iwashima <kuni1840@...il.com>,
<netdev@...r.kernel.org>
Subject: [PATCH v3 net-next 6/6] af_unix: Remove unix_table_locks.
unix_table_locks are to protect the global hash table, unix_socket_table.
The previous commit removed it, so let's clean up the unnecessary locks.
Here is a test result on EC2 c5.9xlarge where 10 processes run concurrently
in different netns and bind 100,000 sockets for each.
without this series : 1m 38s
with this series : 11s
It is ~10x faster because the global hash table is split into 10 netns in
this case.
Signed-off-by: Kuniyuki Iwashima <kuniyu@...zon.com>
---
include/net/af_unix.h | 1 -
net/unix/af_unix.c | 42 ++++++++----------------------------------
net/unix/diag.c | 8 +-------
3 files changed, 9 insertions(+), 42 deletions(-)
diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index b1748c9b6db2..480fa579787e 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -21,7 +21,6 @@ struct sock *unix_peer_get(struct sock *sk);
#define UNIX_HASH_BITS 8
extern unsigned int unix_tot_inflight;
-extern spinlock_t unix_table_locks[UNIX_HASH_SIZE];
struct unix_address {
refcount_t refcnt;
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 9d0b07235dbc..49f6626330c3 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -118,13 +118,11 @@
#include "scm.h"
-spinlock_t unix_table_locks[UNIX_HASH_SIZE];
-EXPORT_SYMBOL_GPL(unix_table_locks);
static atomic_long_t unix_nr_socks;
/* SMP locking strategy:
- * hash table is protected with spinlock unix_table_locks
- * each socket state is protected by separate spin lock.
+ * hash table is protected with spinlock.
+ * each socket state is protected by separate spinlock.
*/
static unsigned int unix_unbound_hash(struct sock *sk)
@@ -166,9 +164,6 @@ static void unix_table_double_lock(struct net *net,
if (hash1 > hash2)
swap(hash1, hash2);
- spin_lock(&unix_table_locks[hash1]);
- spin_lock_nested(&unix_table_locks[hash2], SINGLE_DEPTH_NESTING);
-
spin_lock(&net->unx.table.locks[hash1]);
spin_lock_nested(&net->unx.table.locks[hash2], SINGLE_DEPTH_NESTING);
}
@@ -178,9 +173,6 @@ static void unix_table_double_unlock(struct net *net,
{
spin_unlock(&net->unx.table.locks[hash1]);
spin_unlock(&net->unx.table.locks[hash2]);
-
- spin_unlock(&unix_table_locks[hash1]);
- spin_unlock(&unix_table_locks[hash2]);
}
#ifdef CONFIG_SECURITY_NETWORK
@@ -324,20 +316,16 @@ static void __unix_set_addr_hash(struct net *net, struct sock *sk,
static void unix_remove_socket(struct net *net, struct sock *sk)
{
- spin_lock(&unix_table_locks[sk->sk_hash]);
spin_lock(&net->unx.table.locks[sk->sk_hash]);
__unix_remove_socket(sk);
spin_unlock(&net->unx.table.locks[sk->sk_hash]);
- spin_unlock(&unix_table_locks[sk->sk_hash]);
}
static void unix_insert_unbound_socket(struct net *net, struct sock *sk)
{
- spin_lock(&unix_table_locks[sk->sk_hash]);
spin_lock(&net->unx.table.locks[sk->sk_hash]);
__unix_insert_socket(net, sk);
spin_unlock(&net->unx.table.locks[sk->sk_hash]);
- spin_unlock(&unix_table_locks[sk->sk_hash]);
}
static struct sock *__unix_find_socket_byname(struct net *net,
@@ -362,13 +350,11 @@ static inline struct sock *unix_find_socket_byname(struct net *net,
{
struct sock *s;
- spin_lock(&unix_table_locks[hash]);
spin_lock(&net->unx.table.locks[hash]);
s = __unix_find_socket_byname(net, sunname, len, hash);
if (s)
sock_hold(s);
spin_unlock(&net->unx.table.locks[hash]);
- spin_unlock(&unix_table_locks[hash]);
return s;
}
@@ -377,7 +363,6 @@ static struct sock *unix_find_socket_byinode(struct net *net, struct inode *i)
unsigned int hash = unix_bsd_hash(i);
struct sock *s;
- spin_lock(&unix_table_locks[hash]);
spin_lock(&net->unx.table.locks[hash]);
sk_for_each(s, &net->unx.table.buckets[hash]) {
struct dentry *dentry = unix_sk(s)->path.dentry;
@@ -385,12 +370,10 @@ static struct sock *unix_find_socket_byinode(struct net *net, struct inode *i)
if (dentry && d_backing_inode(dentry) == i) {
sock_hold(s);
spin_unlock(&net->unx.table.locks[hash]);
- spin_unlock(&unix_table_locks[hash]);
return s;
}
}
spin_unlock(&net->unx.table.locks[hash]);
- spin_unlock(&unix_table_locks[hash]);
return NULL;
}
@@ -1551,9 +1534,9 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
*
* The contents of *(otheru->addr) and otheru->path
* are seen fully set up here, since we have found
- * otheru in hash under unix_table_locks. Insertion
- * into the hash chain we'd found it in had been done
- * in an earlier critical area protected by unix_table_locks,
+ * otheru in hash under its lock. Insertion into the
+ * hash chain we'd found it in had been done in an
+ * earlier critical area protected by the chain's lock,
* the same one where we'd set *(otheru->addr) contents,
* as well as otheru->path and otheru->addr itself.
*
@@ -3253,7 +3236,6 @@ static struct sock *unix_get_first(struct seq_file *seq, loff_t *pos)
struct sock *sk;
while (bucket < UNIX_HASH_SIZE) {
- spin_lock(&unix_table_locks[bucket]);
spin_lock(&net->unx.table.locks[bucket]);
sk = unix_from_bucket(seq, pos);
@@ -3261,7 +3243,6 @@ static struct sock *unix_get_first(struct seq_file *seq, loff_t *pos)
return sk;
spin_unlock(&net->unx.table.locks[bucket]);
- spin_unlock(&unix_table_locks[bucket]);
*pos = set_bucket_offset(++bucket, 1);
}
@@ -3280,7 +3261,6 @@ static struct sock *unix_get_next(struct seq_file *seq, struct sock *sk,
spin_unlock(&seq_file_net(seq)->unx.table.locks[bucket]);
- spin_unlock(&unix_table_locks[bucket]);
*pos = set_bucket_offset(++bucket, 1);
@@ -3309,10 +3289,8 @@ static void unix_seq_stop(struct seq_file *seq, void *v)
{
struct sock *sk = v;
- if (sk) {
+ if (sk)
spin_unlock(&seq_file_net(seq)->unx.table.locks[sk->sk_hash]);
- spin_unlock(&unix_table_locks[sk->sk_hash]);
- }
}
static int unix_seq_show(struct seq_file *seq, void *v)
@@ -3337,7 +3315,7 @@ static int unix_seq_show(struct seq_file *seq, void *v)
(s->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING),
sock_i_ino(s));
- if (u->addr) { // under unix_table_locks here
+ if (u->addr) { // under a hash table lock here
int i, len;
seq_putc(seq, ' ');
@@ -3416,7 +3394,6 @@ static int bpf_iter_unix_hold_batch(struct seq_file *seq, struct sock *start_sk)
}
spin_unlock(&seq_file_net(seq)->unx.table.locks[start_sk->sk_hash]);
- spin_unlock(&unix_table_locks[start_sk->sk_hash]);
return expected;
}
@@ -3705,13 +3682,10 @@ static void __init bpf_iter_register(void)
static int __init af_unix_init(void)
{
- int i, rc = -1;
+ int rc = -1;
BUILD_BUG_ON(sizeof(struct unix_skb_parms) > sizeof_field(struct sk_buff, cb));
- for (i = 0; i < UNIX_HASH_SIZE; i++)
- spin_lock_init(&unix_table_locks[i]);
-
rc = proto_register(&unix_dgram_proto, 1);
if (rc != 0) {
pr_crit("%s: Cannot create unix_sock SLAB cache!\n", __func__);
diff --git a/net/unix/diag.c b/net/unix/diag.c
index 4d0f0ca6a1eb..105f522a89fe 100644
--- a/net/unix/diag.c
+++ b/net/unix/diag.c
@@ -13,7 +13,7 @@
static int sk_diag_dump_name(struct sock *sk, struct sk_buff *nlskb)
{
- /* might or might not have unix_table_locks */
+ /* might or might not have a hash table lock */
struct unix_address *addr = smp_load_acquire(&unix_sk(sk)->addr);
if (!addr)
@@ -208,7 +208,6 @@ static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
struct sock *sk;
num = 0;
- spin_lock(&unix_table_locks[slot]);
spin_lock(&net->unx.table.locks[slot]);
sk_for_each(sk, &net->unx.table.buckets[slot]) {
if (num < s_num)
@@ -220,14 +219,12 @@ static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
cb->nlh->nlmsg_seq,
NLM_F_MULTI) < 0) {
spin_unlock(&net->unx.table.locks[slot]);
- spin_unlock(&unix_table_locks[slot]);
goto done;
}
next:
num++;
}
spin_unlock(&net->unx.table.locks[slot]);
- spin_unlock(&unix_table_locks[slot]);
}
done:
cb->args[0] = slot;
@@ -242,18 +239,15 @@ static struct sock *unix_lookup_by_ino(struct net *net, unsigned int ino)
int i;
for (i = 0; i < UNIX_HASH_SIZE; i++) {
- spin_lock(&unix_table_locks[i]);
spin_lock(&net->unx.table.locks[i]);
sk_for_each(sk, &net->unx.table.buckets[i]) {
if (ino == sock_i_ino(sk)) {
sock_hold(sk);
spin_unlock(&net->unx.table.locks[i]);
- spin_unlock(&unix_table_locks[i]);
return sk;
}
}
spin_unlock(&net->unx.table.locks[i]);
- spin_unlock(&unix_table_locks[i]);
}
return NULL;
}
--
2.30.2
Powered by blists - more mailing lists