ipv4: Namespaceify tcp_max_syn_backlog knob

Different namespace application might require different maximal
number of remembered connection requests.

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
index fffd384539852616ff3446bc649f4fb53fe439be..8e3f5b6f26d57cfaf813e3ee243de27494f3db45 100644 (file)
--- a/include/net/netns/ipv4.h
+++ b/include/net/netns/ipv4.h
@@ -122,6 +122,7 @@ struct netns_ipv4 {
        unsigned int sysctl_tcp_notsent_lowat;
        int sysctl_tcp_tw_reuse;
        struct inet_timewait_death_row tcp_death_row;
+       int sysctl_max_syn_backlog;
 
        int sysctl_igmp_max_memberships;
        int sysctl_igmp_max_msf;

diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index 6ebe13eb1c4cbcd84c4b3345b051b3320d7591e6..a12a5d25b27e650166cdd1bd8513317874b714da 100644 (file)
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -1,7 +1,7 @@
 /*
  * NET         Generic infrastructure for Network protocols.
  *
- *             Definitions for request_sock 
+ *             Definitions for request_sock
  *
  * Authors:    Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  *
@@ -123,8 +123,6 @@ static inline void reqsk_put(struct request_sock *req)
                reqsk_free(req);
 }
 
-extern int sysctl_max_syn_backlog;
-
 /*
  * For a TCP Fast Open listener -
  *     lock - protects the access to all the reqsk, which is co-owned by

diff --git a/net/core/request_sock.c b/net/core/request_sock.c
index 5d26056b6d8f01f4db815423d2d78f6f7d25d55f..9b8727c67b58011227cc09098d96a40fee5c5d69 100644 (file)
--- a/net/core/request_sock.c
+++ b/net/core/request_sock.c
@@ -34,8 +34,6 @@
  * and it will increase in proportion to the memory of machine.
  * Note : Dont forget somaxconn that may limit backlog too.
  */
-int sysctl_max_syn_backlog = 256;
-EXPORT_SYMBOL(sysctl_max_syn_backlog);
 
 void reqsk_queue_alloc(struct request_sock_queue *queue)
 {

diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 66f8f1b1dc78c319184c986a2dd87c8973141e86..134d8e19136622360a73498d13be3f640890446f 100644 (file)
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -323,13 +323,6 @@ static struct ctl_table ipv4_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec
        },
-       {
-               .procname       = "tcp_max_syn_backlog",
-               .data           = &sysctl_max_syn_backlog,
-               .maxlen         = sizeof(int),
-               .mode           = 0644,
-               .proc_handler   = proc_dointvec
-       },
        {
                .procname       = "inet_peer_threshold",
                .data           = &inet_peer_threshold,
@@ -960,6 +953,13 @@ static struct ctl_table ipv4_net_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec
        },
+       {
+               .procname       = "tcp_max_syn_backlog",
+               .data           = &init_net.ipv4.sysctl_max_syn_backlog,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = proc_dointvec
+       },
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
        {
                .procname       = "fib_multipath_use_neigh",

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 7f0d81c090ceeff0e6255df8ca89d9269a524377..2e3807d8eba8ba6c37898a057154e67590325903 100644 (file)
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3378,9 +3378,7 @@ void __init tcp_init(void)
 
 
        cnt = tcp_hashinfo.ehash_mask + 1;
-
        sysctl_tcp_max_orphans = cnt / 2;
-       sysctl_max_syn_backlog = max(128, cnt / 256);
 
        tcp_init_mem();
        /* Set per-socket limits to no more than 1/128 the pressure threshold */

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index c614802498359a7c1334e6fb615c48645b8035ea..ec6d843630242074421994b17a851429a51a926c 100644 (file)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -6377,8 +6377,8 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
                }
                /* Kill the following clause, if you dislike this way. */
                else if (!net->ipv4.sysctl_tcp_syncookies &&
-                        (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) <
-                         (sysctl_max_syn_backlog >> 2)) &&
+                        (net->ipv4.sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) <
+                         (net->ipv4.sysctl_max_syn_backlog >> 2)) &&
                         !tcp_peer_is_proven(req, dst, false,
                                             tmp_opt.saw_tstamp)) {
                        /* Without syncookies last quarter of

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 56b5f49e3f9765dd70b4cf2ba45a2662d77141d3..7e4be4f361f3097db4c005cab6cbec0ed2f18a43 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -2419,7 +2419,7 @@ static void __net_exit tcp_sk_exit(struct net *net)
 
 static int __net_init tcp_sk_init(struct net *net)
 {
-       int res, cpu;
+       int res, cpu, cnt;
 
        net->ipv4.tcp_sk = alloc_percpu(struct sock *);
        if (!net->ipv4.tcp_sk)
@@ -2458,10 +2458,13 @@ static int __net_init tcp_sk_init(struct net *net)
        net->ipv4.sysctl_tcp_notsent_lowat = UINT_MAX;
        net->ipv4.sysctl_tcp_tw_reuse = 0;
 
+       cnt = tcp_hashinfo.ehash_mask + 1;
        net->ipv4.tcp_death_row.sysctl_tw_recycle = 0;
-       net->ipv4.tcp_death_row.sysctl_max_tw_buckets = (tcp_hashinfo.ehash_mask + 1) / 2;
+       net->ipv4.tcp_death_row.sysctl_max_tw_buckets = (cnt + 1) / 2;
        net->ipv4.tcp_death_row.hashinfo = &tcp_hashinfo;
 
+       net->ipv4.sysctl_max_syn_backlog = max(128, cnt / 256);
+
        return 0;
 fail:
        tcp_sk_exit(net);