From dd24c00191d5e4a1ae896aafe33c6b8095ab4bd1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 25 Nov 2008 21:17:14 -0800 Subject: [PATCH] net: Use a percpu_counter for orphan_count Instead of using one atomic_t per protocol, use a percpu_counter for "orphan_count", to reduce cache line contention on heavy duty network servers. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/sock.h | 2 +- include/net/tcp.h | 2 +- net/dccp/dccp.h | 2 +- net/dccp/proto.c | 16 ++++++++++------ net/ipv4/inet_connection_sock.c | 4 ++-- net/ipv4/proc.c | 2 +- net/ipv4/tcp.c | 12 +++++++----- net/ipv4/tcp_timer.c | 2 +- 8 files changed, 24 insertions(+), 18 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index a2a3890959c4..5a3a151bd730 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -666,7 +666,7 @@ struct proto { unsigned int obj_size; int slab_flags; - atomic_t *orphan_count; + struct percpu_counter *orphan_count; struct request_sock_ops *rsk_prot; struct timewait_sock_ops *twsk_prot; diff --git a/include/net/tcp.h b/include/net/tcp.h index cbca3b8a133d..de1e91d959b8 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -46,7 +46,7 @@ extern struct inet_hashinfo tcp_hashinfo; -extern atomic_t tcp_orphan_count; +extern struct percpu_counter tcp_orphan_count; extern void tcp_time_wait(struct sock *sk, int state, int timeo); #define MAX_TCP_HEADER (128 + MAX_HEADER) diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h index 031ce350d3c1..33a1127270c1 100644 --- a/net/dccp/dccp.h +++ b/net/dccp/dccp.h @@ -49,7 +49,7 @@ extern int dccp_debug; extern struct inet_hashinfo dccp_hashinfo; -extern atomic_t dccp_orphan_count; +extern struct percpu_counter dccp_orphan_count; extern void dccp_time_wait(struct sock *sk, int state, int timeo); diff --git a/net/dccp/proto.c b/net/dccp/proto.c index ea85c423cdbd..db225f93cd5a 100644 --- a/net/dccp/proto.c +++ b/net/dccp/proto.c @@ -40,8 +40,7 @@ DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly; EXPORT_SYMBOL_GPL(dccp_statistics); -atomic_t dccp_orphan_count = ATOMIC_INIT(0); - +struct percpu_counter dccp_orphan_count; EXPORT_SYMBOL_GPL(dccp_orphan_count); struct inet_hashinfo dccp_hashinfo; @@ -1000,7 +999,7 @@ adjudge_to_death: state = sk->sk_state; sock_hold(sk); sock_orphan(sk); - atomic_inc(sk->sk_prot->orphan_count); + percpu_counter_inc(sk->sk_prot->orphan_count); /* * It is the last release_sock in its life. It will remove backlog. @@ -1064,18 +1063,21 @@ static int __init dccp_init(void) { unsigned long goal; int ehash_order, bhash_order, i; - int rc = -ENOBUFS; + int rc; BUILD_BUG_ON(sizeof(struct dccp_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb)); - + rc = percpu_counter_init(&dccp_orphan_count, 0); + if (rc) + goto out; + rc = -ENOBUFS; inet_hashinfo_init(&dccp_hashinfo); dccp_hashinfo.bind_bucket_cachep = kmem_cache_create("dccp_bind_bucket", sizeof(struct inet_bind_bucket), 0, SLAB_HWCACHE_ALIGN, NULL); if (!dccp_hashinfo.bind_bucket_cachep) - goto out; + goto out_free_percpu; /* * Size and allocate the main established and bind bucket @@ -1168,6 +1170,8 @@ out_free_dccp_ehash: out_free_bind_bucket_cachep: kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep); dccp_hashinfo.bind_bucket_cachep = NULL; +out_free_percpu: + percpu_counter_destroy(&dccp_orphan_count); goto out; } diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 05af807ca9b9..1ccdbba528be 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -561,7 +561,7 @@ void inet_csk_destroy_sock(struct sock *sk) sk_refcnt_debug_release(sk); - atomic_dec(sk->sk_prot->orphan_count); + percpu_counter_dec(sk->sk_prot->orphan_count); sock_put(sk); } @@ -641,7 +641,7 @@ void inet_csk_listen_stop(struct sock *sk) sock_orphan(child); - atomic_inc(sk->sk_prot->orphan_count); + percpu_counter_inc(sk->sk_prot->orphan_count); inet_csk_destroy_sock(child); diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index 4944b47ad628..614958b7c276 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -54,7 +54,7 @@ static int sockstat_seq_show(struct seq_file *seq, void *v) socket_seq_show(seq); seq_printf(seq, "TCP: inuse %d orphan %d tw %d alloc %d mem %d\n", sock_prot_inuse_get(net, &tcp_prot), - atomic_read(&tcp_orphan_count), + (int)percpu_counter_sum_positive(&tcp_orphan_count), tcp_death_row.tw_count, (int)percpu_counter_sum_positive(&tcp_sockets_allocated), atomic_read(&tcp_memory_allocated)); diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index e6fade9ebf62..019243408623 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -277,8 +277,7 @@ int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT; -atomic_t tcp_orphan_count = ATOMIC_INIT(0); - +struct percpu_counter tcp_orphan_count; EXPORT_SYMBOL_GPL(tcp_orphan_count); int sysctl_tcp_mem[3] __read_mostly; @@ -1837,7 +1836,7 @@ adjudge_to_death: state = sk->sk_state; sock_hold(sk); sock_orphan(sk); - atomic_inc(sk->sk_prot->orphan_count); + percpu_counter_inc(sk->sk_prot->orphan_count); /* It is the last release_sock in its life. It will remove backlog. */ release_sock(sk); @@ -1888,9 +1887,11 @@ adjudge_to_death: } } if (sk->sk_state != TCP_CLOSE) { + int orphan_count = percpu_counter_read_positive( + sk->sk_prot->orphan_count); + sk_mem_reclaim(sk); - if (tcp_too_many_orphans(sk, - atomic_read(sk->sk_prot->orphan_count))) { + if (tcp_too_many_orphans(sk, orphan_count)) { if (net_ratelimit()) printk(KERN_INFO "TCP: too many of orphaned " "sockets\n"); @@ -2689,6 +2690,7 @@ void __init tcp_init(void) BUILD_BUG_ON(sizeof(struct tcp_skb_cb) > sizeof(skb->cb)); percpu_counter_init(&tcp_sockets_allocated, 0); + percpu_counter_init(&tcp_orphan_count, 0); tcp_hashinfo.bind_bucket_cachep = kmem_cache_create("tcp_bind_bucket", sizeof(struct inet_bind_bucket), 0, diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index 3df339e3e363..cc4e6d27dedc 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -65,7 +65,7 @@ static void tcp_write_err(struct sock *sk) static int tcp_out_of_resources(struct sock *sk, int do_reset) { struct tcp_sock *tp = tcp_sk(sk); - int orphans = atomic_read(&tcp_orphan_count); + int orphans = percpu_counter_read_positive(&tcp_orphan_count); /* If peer does not open window for long time, or did not transmit * anything for long time, penalize it. */ -- 2.39.2