[ICMP]: Allocate data for __icmp(v6)_sk dynamically.

Own __icmp(v6)_sk should be present in each namespace. So, it should be
allocated dynamically. Though, alloc_percpu does not fit the case as it
implies additional dereferrence for no bonus.

Allocate data for pointers just like __percpu_alloc_mask does and place
pointers to struct sock into this array.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 5 deletions

diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 18f220a04486..3368f32fe226 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -80,8 +80,8 @@ EXPORT_SYMBOL(icmpv6msg_statistics);
  *
  *      On SMP we have one ICMP socket per-cpu.
  */
-static DEFINE_PER_CPU(struct sock *, __icmpv6_sk) = NULL;
-#define icmpv6_sk       __get_cpu_var(__icmpv6_sk)
+static struct sock **__icmpv6_sk = NULL;
+#define icmpv6_sk       (__icmpv6_sk[smp_processor_id()])
 
 static int icmpv6_rcv(struct sk_buff *skb);
 
@@ -785,6 +785,10 @@ int __init icmpv6_init(void)
         struct sock *sk;
         int err, i, j;
 
+        __icmpv6_sk = kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL);
+        if (__icmpv6_sk == NULL)
+                return -ENOMEM;
+
         for_each_possible_cpu(i) {
                 struct socket *sock;
                 err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6,
@@ -797,7 +801,7 @@ int __init icmpv6_init(void)
                         goto fail;
                 }
 
-                per_cpu(__icmpv6_sk, i) = sk = sock->sk;
+                __icmpv6_sk[i] = sk = sock->sk;
                 sk->sk_allocation = GFP_ATOMIC;
                 /*
                  * Split off their lock-class, because sk->sk_dst_lock
@@ -830,7 +834,7 @@ int __init icmpv6_init(void)
         for (j = 0; j < i; j++) {
                 if (!cpu_possible(j))
                         continue;
-                sock_release(per_cpu(__icmpv6_sk, j)->sk_socket);
+                sock_release(__icmpv6_sk[j]->sk_socket);
         }
 
         return err;
@@ -841,7 +845,7 @@ void icmpv6_cleanup(void)
         int i;
 
         for_each_possible_cpu(i) {
-                sock_release(per_cpu(__icmpv6_sk, i)->sk_socket);
+                sock_release(__icmpv6_sk[i]->sk_socket);
         }
         inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
 }