From 3b81af711d639cdcf820836bad6b4ac0f5a761fa Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 14 May 2012 02:01:46 +0200 Subject: [PATCH] netfilter: xt_HMARK: modulus is expensive for hash calculation Use: ((u64)(HASH_VAL * HASH_SIZE)) >> 32 as suggested by David S. Miller. Signed-off-by: Pablo Neira Ayuso --- net/netfilter/xt_HMARK.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netfilter/xt_HMARK.c b/net/netfilter/xt_HMARK.c index 5817d03..0a96a43 100644 --- a/net/netfilter/xt_HMARK.c +++ b/net/netfilter/xt_HMARK.c @@ -109,7 +109,7 @@ hmark_hash(struct hmark_tuple *t, const struct xt_hmark_info *info) hash = jhash_3words(t->src, t->dst, t->uports.v32, info->hashrnd); hash = hash ^ (t->proto & info->proto_mask); - return (hash % info->hmodulus) + info->hoffset; + return (((u64)hash * info->hmodulus) >> 32) + info->hoffset; } static void -- 1.7.10