[SOCK][NETNS]: Add the percpu prot_inuse counter in the struct net.

Such an accounting would cost us two more dereferences to get the
percpu variable from the struct net, so I make sock_prot_inuse_get
and _add calls work differently depending on CONFIG_NET_NS - without
it old optimized routines are used.

The per-cpu counter for init_net is prepared in core_initcall, so
that even af_inet, that starts as fs_initcall, will already have the
init_net prepared.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/netns/core.h b/include/net/netns/core.h
index 0e8c0f8435d48ebed0d5c2f6b12cbeff258ceff1..24d4be76bbd140c0b0778cc2f1144d446fb7cb7d 100644 (file)
--- a/include/net/netns/core.h
+++ b/include/net/netns/core.h
@@ -2,12 +2,15 @@
 #define __NETNS_CORE_H__
 
 struct ctl_table_header;
+struct prot_inuse;
 
 struct netns_core {
        /* core sysctls */
        struct ctl_table_header *sysctl_hdr;
 
        int     sysctl_somaxconn;
+
+       struct prot_inuse       *inuse;
 };
 
 #endif

diff --git a/net/core/sock.c b/net/core/sock.c
index 6f36ab91bb5970bd9fe5c4f847fb2c0e5af8997d..83e11f7260ffb1c3c3bd28c7c578472f6dfdf631 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1947,6 +1947,53 @@ struct prot_inuse {
 };
 
 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
+
+#ifdef CONFIG_NET_NS
+void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
+{
+       int cpu = smp_processor_id();
+       per_cpu_ptr(net->core.inuse, cpu)->val[prot->inuse_idx] += val;
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
+
+int sock_prot_inuse_get(struct net *net, struct proto *prot)
+{
+       int cpu, idx = prot->inuse_idx;
+       int res = 0;
+
+       for_each_possible_cpu(cpu)
+               res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
+
+       return res >= 0 ? res : 0;
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
+
+static int sock_inuse_init_net(struct net *net)
+{
+       net->core.inuse = alloc_percpu(struct prot_inuse);
+       return net->core.inuse ? 0 : -ENOMEM;
+}
+
+static void sock_inuse_exit_net(struct net *net)
+{
+       free_percpu(net->core.inuse);
+}
+
+static struct pernet_operations net_inuse_ops = {
+       .init = sock_inuse_init_net,
+       .exit = sock_inuse_exit_net,
+};
+
+static __init int net_inuse_init(void)
+{
+       if (register_pernet_subsys(&net_inuse_ops))
+               panic("Cannot initialize net inuse counters");
+
+       return 0;
+}
+
+core_initcall(net_inuse_init);
+#else
 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
 
 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
@@ -1966,6 +2013,7 @@ int sock_prot_inuse_get(struct net *net, struct proto *prot)
        return res >= 0 ? res : 0;
 }
 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
+#endif
 
 static void assign_proto_idx(struct proto *prot)
 {