1 /* 2 * 3 * SNMP MIB entries for the IP subsystem. 4 * 5 * Alan Cox <gw4pts@gw4pts.ampr.org> 6 * 7 * We don't chose to implement SNMP in the kernel (this would 8 * be silly as SNMP is a pain in the backside in places). We do 9 * however need to collect the MIB statistics and export them 10 * out of /proc (eventually) 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License 14 * as published by the Free Software Foundation; either version 15 * 2 of the License, or (at your option) any later version. 16 * 17 * $Id: snmp.h,v 1.19 2001/06/14 13:40:46 davem Exp $ 18 * 19 */ 20 21 #ifndef _SNMP_H 22 #define _SNMP_H 23 24 #include <linux/cache.h> 25 #include <linux/snmp.h> 26 27 /* 28 * Mibs are stored in array of unsigned long. 29 */ 30 /* 31 * struct snmp_mib{} 32 * - list of entries for particular API (such as /proc/net/snmp) 33 * - name of entries. 34 */ 35 struct snmp_mib { 36 char *name; 37 int entry; 38 }; 39 40 #define SNMP_MIB_ITEM(_name,_entry) { \ 41 .name = _name, \ 42 .entry = _entry, \ 43 } 44 45 #define SNMP_MIB_SENTINEL { \ 46 .name = NULL, \ 47 .entry = 0, \ 48 } 49 50 /* 51 * We use all unsigned longs. Linux will soon be so reliable that even 52 * these will rapidly get too small 8-). Seriously consider the IpInReceives 53 * count on the 20Gb/s + networks people expect in a few years time! 54 */ 55 56 /* 57 * The rule for padding: 58 * Best is power of two because then the right structure can be found by a 59 * simple shift. The structure should be always cache line aligned. 60 * gcc needs n=alignto(cachelinesize, popcnt(sizeof(bla_mib))) shift/add 61 * instructions to emulate multiply in case it is not power-of-two. 62 * Currently n is always <=3 for all sizes so simple cache line alignment 63 * is enough. 64 * 65 * The best solution would be a global CPU local area , especially on 64 66 * and 128byte cacheline machine it makes a *lot* of sense -AK 67 */ 68 69 #define __SNMP_MIB_ALIGN__ ____cacheline_aligned 70 71 /* IPstats */ 72 #define IPSTATS_MIB_MAX __IPSTATS_MIB_MAX 73 struct ipstats_mib { 74 unsigned long mibs[IPSTATS_MIB_MAX]; 75 } __SNMP_MIB_ALIGN__; 76 77 /* ICMP */ 78 #define ICMP_MIB_DUMMY __ICMP_MIB_MAX 79 #define ICMP_MIB_MAX (__ICMP_MIB_MAX + 1) 80 81 struct icmp_mib { 82 unsigned long mibs[ICMP_MIB_MAX]; 83 } __SNMP_MIB_ALIGN__; 84 85 /* ICMP6 (IPv6-ICMP) */ 86 #define ICMP6_MIB_MAX __ICMP6_MIB_MAX 87 struct icmpv6_mib { 88 unsigned long mibs[ICMP6_MIB_MAX]; 89 } __SNMP_MIB_ALIGN__; 90 91 /* TCP */ 92 #define TCP_MIB_MAX __TCP_MIB_MAX 93 struct tcp_mib { 94 unsigned long mibs[TCP_MIB_MAX]; 95 } __SNMP_MIB_ALIGN__; 96 97 /* UDP */ 98 #define UDP_MIB_MAX __UDP_MIB_MAX 99 struct udp_mib { 100 unsigned long mibs[UDP_MIB_MAX]; 101 } __SNMP_MIB_ALIGN__; 102 103 /* Linux */ 104 #define LINUX_MIB_MAX __LINUX_MIB_MAX 105 struct linux_mib { 106 unsigned long mibs[LINUX_MIB_MAX]; 107 }; 108 109 110 /* 111 * FIXME: On x86 and some other CPUs the split into user and softirq parts 112 * is not needed because addl $1,memory is atomic against interrupts (but 113 * atomic_inc would be overkill because of the lock cycles). Wants new 114 * nonlocked_atomic_inc() primitives -AK 115 */ 116 #define DEFINE_SNMP_STAT(type, name) \ 117 __typeof__(type) *name[2] 118 #define DECLARE_SNMP_STAT(type, name) \ 119 extern __typeof__(type) *name[2] 120 121 #define SNMP_STAT_BHPTR(name) (name[0]) 122 #define SNMP_STAT_USRPTR(name) (name[1]) 123 124 #define SNMP_INC_STATS_BH(mib, field) \ 125 (per_cpu_ptr(mib[0], raw_smp_processor_id())->mibs[field]++) 126 #define SNMP_INC_STATS_OFFSET_BH(mib, field, offset) \ 127 (per_cpu_ptr(mib[0], raw_smp_processor_id())->mibs[field + (offset)]++) 128 #define SNMP_INC_STATS_USER(mib, field) \ 129 (per_cpu_ptr(mib[1], raw_smp_processor_id())->mibs[field]++) 130 #define SNMP_INC_STATS(mib, field) \ 131 (per_cpu_ptr(mib[!in_softirq()], raw_smp_processor_id())->mibs[field]++) 132 #define SNMP_DEC_STATS(mib, field) \ 133 (per_cpu_ptr(mib[!in_softirq()], raw_smp_processor_id())->mibs[field]--) 134 #define SNMP_ADD_STATS_BH(mib, field, addend) \ 135 (per_cpu_ptr(mib[0], raw_smp_processor_id())->mibs[field] += addend) 136 #define SNMP_ADD_STATS_USER(mib, field, addend) \ 137 (per_cpu_ptr(mib[1], raw_smp_processor_id())->mibs[field] += addend) 138 139 #endif 140