diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.co.jp> | 2021-11-24 11:14:30 +0900 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-11-26 18:01:58 -0800 |
| commit | afd20b9290e184c203fe22f2d6b80dc7127ba724 (patch) | |
| tree | 26608b7fc089541250d5cb8e17b6c40659726284 /net/unix/diag.c | |
| parent | e6b4b873896f0e9298f70d25726f4bb1e1b265ba (diff) | |
af_unix: Replace the big lock with small locks.
The hash table of AF_UNIX sockets is protected by the single lock. This
patch replaces it with per-hash locks.
The effect is noticeable when we handle multiple sockets simultaneously.
Here is a test result on an EC2 c5.24xlarge instance. It shows latency
(under 10us only) in unix_insert_unbound_socket() while 64 CPUs creating
1024 sockets for each in parallel.
Without this patch:
nsec : count distribution
0 : 179 | |
500 : 3021 |********* |
1000 : 6271 |******************* |
1500 : 6318 |******************* |
2000 : 5828 |***************** |
2500 : 5124 |*************** |
3000 : 4426 |************* |
3500 : 3672 |*********** |
4000 : 3138 |********* |
4500 : 2811 |******** |
5000 : 2384 |******* |
5500 : 2023 |****** |
6000 : 1954 |***** |
6500 : 1737 |***** |
7000 : 1749 |***** |
7500 : 1520 |**** |
8000 : 1469 |**** |
8500 : 1394 |**** |
9000 : 1232 |*** |
9500 : 1138 |*** |
10000 : 994 |*** |
With this patch:
nsec : count distribution
0 : 1634 |**** |
500 : 13170 |****************************************|
1000 : 13156 |*************************************** |
1500 : 9010 |*************************** |
2000 : 6363 |******************* |
2500 : 4443 |************* |
3000 : 3240 |********* |
3500 : 2549 |******* |
4000 : 1872 |***** |
4500 : 1504 |**** |
5000 : 1247 |*** |
5500 : 1035 |*** |
6000 : 889 |** |
6500 : 744 |** |
7000 : 634 |* |
7500 : 498 |* |
8000 : 433 |* |
8500 : 355 |* |
9000 : 336 |* |
9500 : 284 | |
10000 : 243 | |
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/unix/diag.c')
| -rw-r--r-- | net/unix/diag.c | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/net/unix/diag.c b/net/unix/diag.c index db555f267407..bb0b5ea1655f 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_lock */ + /* might or might not have unix_table_locks */ struct unix_address *addr = smp_load_acquire(&unix_sk(sk)->addr); if (!addr) @@ -204,13 +204,13 @@ static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) s_slot = cb->args[0]; num = s_num = cb->args[1]; - spin_lock(&unix_table_lock); for (slot = s_slot; slot < ARRAY_SIZE(unix_socket_table); s_num = 0, slot++) { struct sock *sk; num = 0; + spin_lock(&unix_table_locks[slot]); sk_for_each(sk, &unix_socket_table[slot]) { if (!net_eq(sock_net(sk), net)) continue; @@ -221,14 +221,16 @@ static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) if (sk_diag_dump(sk, skb, req, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, - NLM_F_MULTI) < 0) + NLM_F_MULTI) < 0) { + spin_unlock(&unix_table_locks[slot]); goto done; + } next: num++; } + spin_unlock(&unix_table_locks[slot]); } done: - spin_unlock(&unix_table_lock); cb->args[0] = slot; cb->args[1] = num; @@ -237,21 +239,19 @@ done: static struct sock *unix_lookup_by_ino(unsigned int ino) { - int i; struct sock *sk; + int i; - spin_lock(&unix_table_lock); for (i = 0; i < ARRAY_SIZE(unix_socket_table); i++) { + spin_lock(&unix_table_locks[i]); sk_for_each(sk, &unix_socket_table[i]) if (ino == sock_i_ino(sk)) { sock_hold(sk); - spin_unlock(&unix_table_lock); - + spin_unlock(&unix_table_locks[i]); return sk; } + spin_unlock(&unix_table_locks[i]); } - - spin_unlock(&unix_table_lock); return NULL; } |