ipv6: sr: static percpu allocation for hmac_ring

Current allocations are not NUMA aware, and lack proper
cleanup in case of error.

It is perfectly fine to use static per cpu allocations for 256 bytes
per cpu.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Lebrun <david.lebrun@uclouvain.be>
Acked-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c
index ef1c8a4..6389bf3 100644
--- a/net/ipv6/seg6_hmac.c
+++ b/net/ipv6/seg6_hmac.c
@@ -45,7 +45,7 @@
 #include <net/seg6_hmac.h>
 #include <linux/random.h>
 
-static char * __percpu *hmac_ring;
+static DEFINE_PER_CPU(char [SEG6_HMAC_RING_SIZE], hmac_ring);
 
 static int seg6_hmac_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
 {
@@ -192,7 +192,7 @@
 	 */
 
 	local_bh_disable();
-	ring = *this_cpu_ptr(hmac_ring);
+	ring = this_cpu_ptr(hmac_ring);
 	off = ring;
 
 	/* source address */
@@ -353,27 +353,6 @@
 }
 EXPORT_SYMBOL(seg6_push_hmac);
 
-static int seg6_hmac_init_ring(void)
-{
-	int i;
-
-	hmac_ring = alloc_percpu(char *);
-
-	if (!hmac_ring)
-		return -ENOMEM;
-
-	for_each_possible_cpu(i) {
-		char *ring = kzalloc(SEG6_HMAC_RING_SIZE, GFP_KERNEL);
-
-		if (!ring)
-			return -ENOMEM;
-
-		*per_cpu_ptr(hmac_ring, i) = ring;
-	}
-
-	return 0;
-}
-
 static int seg6_hmac_init_algo(void)
 {
 	struct seg6_hmac_algo *algo;
@@ -422,16 +401,7 @@
 
 int __init seg6_hmac_init(void)
 {
-	int ret;
-
-	ret = seg6_hmac_init_ring();
-	if (ret < 0)
-		goto out;
-
-	ret = seg6_hmac_init_algo();
-
-out:
-	return ret;
+	return seg6_hmac_init_algo();
 }
 EXPORT_SYMBOL(seg6_hmac_init);
 
@@ -450,13 +420,6 @@
 	struct seg6_hmac_algo *algo = NULL;
 	int i, alg_count, cpu;
 
-	for_each_possible_cpu(i) {
-		char *ring = *per_cpu_ptr(hmac_ring, i);
-
-		kfree(ring);
-	}
-	free_percpu(hmac_ring);
-
 	alg_count = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);
 	for (i = 0; i < alg_count; i++) {
 		algo = &hmac_algos[i];