ip_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE, skb); 
static int icmp_packet(struct ip_conntrack *ct,		       const struct sk_buff *skb,		       enum ip_conntrack_info ctinfo){	/* Try to delete connection immediately after all replies:           won't actually vanish as we still have skb, and del_timer           means this will only run once even if count hits zero twice           (theoretically possible with SMP) */	if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) {		if (atomic_dec_and_test(&ct->proto.icmp.count)		    && del_timer(&ct->timeout))			ct->timeout.function((unsigned long)ct);	} else {		atomic_inc(&ct->proto.icmp.count);		ip_ct_refresh_acct(ct, ctinfo, skb, ip_ct_icmp_timeout);	}	return NF_ACCEPT;}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/ac3247baf8ecadf168642e3898b0212c29c79715/ip_conntrack_proto_icmp.c/clean/net/ipv4/netfilter/ip_conntrack_proto_icmp.c