[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, 10 insertions, 5 deletions

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 9bcf263f06ca..7c62a0da5264 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -229,8 +229,8 @@ static const struct icmp_control icmp_pointers[NR_ICMP_TYPES+1];
  *
  *      On SMP we have one ICMP socket per-cpu.
  */
-static DEFINE_PER_CPU(struct sock *, __icmp_sk) = NULL;
-#define icmp_sk         __get_cpu_var(__icmp_sk)
+static struct sock **__icmp_sk = NULL;
+#define icmp_sk         (__icmp_sk[smp_processor_id()])
 
 static inline int icmp_xmit_lock(struct sock *sk)
 {
@@ -1149,18 +1149,23 @@ static void __exit icmp_exit(void)
         for_each_possible_cpu(i) {
                 struct sock *sk;
 
-                sk = per_cpu(__icmp_sk, i);
+                sk = __icmp_sk[i];
                 if (sk == NULL)
                         continue;
-                per_cpu(__icmp_sk, i) = NULL;
                 sock_release(sk->sk_socket);
         }
+        kfree(__icmp_sk);
+        __icmp_sk = NULL;
 }
 
 int __init icmp_init(void)
 {
         int i, err;
 
+        __icmp_sk = kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL);
+        if (__icmp_sk == NULL)
+                return -ENOMEM;
+
         for_each_possible_cpu(i) {
                 struct sock *sk;
                 struct socket *sock;
@@ -1170,7 +1175,7 @@ int __init icmp_init(void)
                 if (err < 0)
                         goto fail;
 
-                per_cpu(__icmp_sk, i) = sk = sock->sk;
+                __icmp_sk[i] = sk = sock->sk;
                 sk->sk_allocation = GFP_ATOMIC;
 
                 /* Enough space for 2 64K ICMP packets, including