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 */ 18 19 #ifndef _SNMP_H 20 #define _SNMP_H 21 22 #include <linux/cache.h> 23 #include <linux/snmp.h> 24 #include <linux/smp.h> 25 26 /* 27 * Mibs are stored in array of unsigned long. 28 */ 29 /* 30 * struct snmp_mib{} 31 * - list of entries for particular API (such as /proc/net/snmp) 32 * - name of entries. 33 */ 34 struct snmp_mib { 35 char *name; 36 int entry; 37 }; 38 39 #define SNMP_MIB_ITEM(_name,_entry) { \ 40 .name = _name, \ 41 .entry = _entry, \ 42 } 43 44 #define SNMP_MIB_SENTINEL { \ 45 .name = NULL, \ 46 .entry = 0, \ 47 } 48 49 /* 50 * We use all unsigned longs. Linux will soon be so reliable that even 51 * these will rapidly get too small 8-). Seriously consider the IpInReceives 52 * count on the 20Gb/s + networks people expect in a few years time! 53 */ 54 55 /* 56 * The rule for padding: 57 * Best is power of two because then the right structure can be found by a 58 * simple shift. The structure should be always cache line aligned. 59 * gcc needs n=alignto(cachelinesize, popcnt(sizeof(bla_mib))) shift/add 60 * instructions to emulate multiply in case it is not power-of-two. 61 * Currently n is always <=3 for all sizes so simple cache line alignment 62 * is enough. 63 * 64 * The best solution would be a global CPU local area , especially on 64 65 * and 128byte cacheline machine it makes a *lot* of sense -AK 66 */ 67 68 #define __SNMP_MIB_ALIGN__ ____cacheline_aligned 69 70 /* IPstats */ 71 #define IPSTATS_MIB_MAX __IPSTATS_MIB_MAX 72 struct ipstats_mib { 73 unsigned long mibs[IPSTATS_MIB_MAX]; 74 } __SNMP_MIB_ALIGN__; 75 76 /* ICMP */ 77 #define ICMP_MIB_DUMMY __ICMP_MIB_MAX 78 #define ICMP_MIB_MAX (__ICMP_MIB_MAX + 1) 79 80 struct icmp_mib { 81 unsigned long mibs[ICMP_MIB_MAX]; 82 } __SNMP_MIB_ALIGN__; 83 84 #define ICMPMSG_MIB_MAX __ICMPMSG_MIB_MAX 85 struct icmpmsg_mib { 86 unsigned long mibs[ICMPMSG_MIB_MAX]; 87 } __SNMP_MIB_ALIGN__; 88 89 /* ICMP6 (IPv6-ICMP) */ 90 #define ICMP6_MIB_MAX __ICMP6_MIB_MAX 91 struct icmpv6_mib { 92 unsigned long mibs[ICMP6_MIB_MAX]; 93 } __SNMP_MIB_ALIGN__; 94 95 #define ICMP6MSG_MIB_MAX __ICMP6MSG_MIB_MAX 96 struct icmpv6msg_mib { 97 unsigned long mibs[ICMP6MSG_MIB_MAX]; 98 } __SNMP_MIB_ALIGN__; 99 100 101 /* TCP */ 102 #define TCP_MIB_MAX __TCP_MIB_MAX 103 struct tcp_mib { 104 unsigned long mibs[TCP_MIB_MAX]; 105 } __SNMP_MIB_ALIGN__; 106 107 /* UDP */ 108 #define UDP_MIB_MAX __UDP_MIB_MAX 109 struct udp_mib { 110 unsigned long mibs[UDP_MIB_MAX]; 111 } __SNMP_MIB_ALIGN__; 112 113 /* Linux */ 114 #define LINUX_MIB_MAX __LINUX_MIB_MAX 115 struct linux_mib { 116 unsigned long mibs[LINUX_MIB_MAX]; 117 }; 118 119 /* Linux Xfrm */ 120 #define LINUX_MIB_XFRMMAX __LINUX_MIB_XFRMMAX 121 struct linux_xfrm_mib { 122 unsigned long mibs[LINUX_MIB_XFRMMAX]; 123 }; 124 125 /* 126 * FIXME: On x86 and some other CPUs the split into user and softirq parts 127 * is not needed because addl $1,memory is atomic against interrupts (but 128 * atomic_inc would be overkill because of the lock cycles). Wants new 129 * nonlocked_atomic_inc() primitives -AK 130 */ 131 #define DEFINE_SNMP_STAT(type, name) \ 132 __typeof__(type) *name[2] 133 #define DECLARE_SNMP_STAT(type, name) \ 134 extern __typeof__(type) *name[2] 135 136 #define SNMP_STAT_BHPTR(name) (name[0]) 137 #define SNMP_STAT_USRPTR(name) (name[1]) 138 139 #define SNMP_INC_STATS_BH(mib, field) \ 140 (per_cpu_ptr(mib[0], raw_smp_processor_id())->mibs[field]++) 141 #define SNMP_INC_STATS_USER(mib, field) \ 142 do { \ 143 per_cpu_ptr(mib[1], get_cpu())->mibs[field]++; \ 144 put_cpu(); \ 145 } while (0) 146 #define SNMP_INC_STATS(mib, field) \ 147 do { \ 148 per_cpu_ptr(mib[!in_softirq()], get_cpu())->mibs[field]++; \ 149 put_cpu(); \ 150 } while (0) 151 #define SNMP_DEC_STATS(mib, field) \ 152 do { \ 153 per_cpu_ptr(mib[!in_softirq()], get_cpu())->mibs[field]--; \ 154 put_cpu(); \ 155 } while (0) 156 #define SNMP_ADD_STATS_BH(mib, field, addend) \ 157 (per_cpu_ptr(mib[0], raw_smp_processor_id())->mibs[field] += addend) 158 #define SNMP_ADD_STATS_USER(mib, field, addend) \ 159 do { \ 160 per_cpu_ptr(mib[1], get_cpu())->mibs[field] += addend; \ 161 put_cpu(); \ 162 } while (0) 163 164 #endif 165