1 /* Kernel module to match running CPU */ 2 3 /* 4 * Might be used to distribute connections on several daemons, if 5 * RPS (Remote Packet Steering) is enabled or NIC is multiqueue capable, 6 * each RX queue IRQ affined to one CPU (1:1 mapping) 7 * 8 */ 9 10 /* (C) 2010 Eric Dumazet 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License version 2 as 14 * published by the Free Software Foundation. 15 */ 16 17 #include <linux/module.h> 18 #include <linux/skbuff.h> 19 #include <linux/netfilter/xt_cpu.h> 20 #include <linux/netfilter/x_tables.h> 21 22 MODULE_LICENSE("GPL"); 23 MODULE_AUTHOR("Eric Dumazet <[email protected]>"); 24 MODULE_DESCRIPTION("Xtables: CPU match"); 25 26 static int cpu_mt_check(const struct xt_mtchk_param *par) 27 { 28 const struct xt_cpu_info *info = par->matchinfo; 29 30 if (info->invert & ~1) 31 return -EINVAL; 32 return 0; 33 } 34 35 static bool cpu_mt(const struct sk_buff *skb, struct xt_action_param *par) 36 { 37 const struct xt_cpu_info *info = par->matchinfo; 38 39 return (info->cpu == smp_processor_id()) ^ info->invert; 40 } 41 42 static struct xt_match cpu_mt_reg __read_mostly = { 43 .name = "cpu", 44 .revision = 0, 45 .family = NFPROTO_UNSPEC, 46 .checkentry = cpu_mt_check, 47 .match = cpu_mt, 48 .matchsize = sizeof(struct xt_cpu_info), 49 .me = THIS_MODULE, 50 }; 51 52 static int __init cpu_mt_init(void) 53 { 54 return xt_register_match(&cpu_mt_reg); 55 } 56 57 static void __exit cpu_mt_exit(void) 58 { 59 xt_unregister_match(&cpu_mt_reg); 60 } 61 62 module_init(cpu_mt_init); 63 module_exit(cpu_mt_exit); 64