>From 49318a2c917f970373e66e21d747a38a595eb462 Mon Sep 17 00:00:00 2001 From: Glauber Costa Date: Fri, 27 Jan 2012 19:34:17 +0400 Subject: [PATCH] fix tcp sysctl initialization with CONFIG_SYSCTL disabled. sysctl_tcp_mem initialization was moved to sysctl_tcp_ipv4.c in commit 3dc43e3e4d0b52197d3205214fe8f162f9e0c334, since it became a per-ns value. That code, however, will never run when CONFIG_SYSCTL is disabled, leading to bogus values on those fields. This patch fixes it by keeping an initialization code in tcp_init(). It will be overwritten by the first net namespace init if CONFIG_SYSCTL is compiled in, and do the right thing if it is compiled out. Signed-off-by: Glauber Costa Reported-by: Ingo Molnar --- include/net/tcp.h | 2 ++ net/ipv4/sysctl_net_ipv4.c | 1 + net/ipv4/tcp.c | 16 +++++++++++++--- 3 files changed, 16 insertions(+), 3 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 0118ea9..b04a3e9 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -311,6 +311,8 @@ extern struct proto tcp_prot; #define TCP_ADD_STATS_USER(net, field, val) SNMP_ADD_STATS_USER((net)->mib.tcp_statistics, field, val) #define TCP_ADD_STATS(net, field, val) SNMP_ADD_STATS((net)->mib.tcp_statistics, field, val) +extern void init_tcp_mem(struct net *net); + extern void tcp_v4_err(struct sk_buff *skb, u32); extern void tcp_shutdown (struct sock *sk, int how); diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index 4aa7e9d..1d67cde 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -814,6 +814,7 @@ static __net_init int ipv4_sysctl_init_net(struct net *net) net->ipv4.sysctl_rt_cache_rebuild_count = 4; + init_tcp_mem(net); limit = nr_free_buffer_pages() / 8; limit = max(limit, 128UL); net->ipv4.sysctl_tcp_mem[0] = limit / 4 * 3; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 9bcdec3..34e4051 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3216,6 +3216,16 @@ static int __init set_thash_entries(char *str) } __setup("thash_entries=", set_thash_entries); +void init_tcp_mem(struct net *net) +{ + /* Set per-socket limits to no more than 1/128 the pressure threshold */ + unsigned long limit = nr_free_buffer_pages() / 8; + limit = max(limit, 128UL); + net->ipv4.sysctl_tcp_mem[0] = limit / 4 * 3; + net->ipv4.sysctl_tcp_mem[1] = limit; + net->ipv4.sysctl_tcp_mem[2] = net->ipv4.sysctl_tcp_mem[0] * 2; +} + void __init tcp_init(void) { struct sk_buff *skb = NULL; @@ -3276,9 +3286,9 @@ void __init tcp_init(void) sysctl_tcp_max_orphans = cnt / 2; sysctl_max_syn_backlog = max(128, cnt / 256); - /* Set per-socket limits to no more than 1/128 the pressure threshold */ - limit = ((unsigned long)init_net.ipv4.sysctl_tcp_mem[1]) - << (PAGE_SHIFT - 7); + init_tcp_mem(&init_net); + limit = nr_free_buffer_pages() / 8; + limit = max(limit, 128UL); max_share = min(4UL*1024*1024, limit); sysctl_tcp_wmem[0] = SK_MEM_QUANTUM; -- 1.7.7.4