xref: /openbmc/linux/include/net/snmp.h (revision 22246614)
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 #include <linux/smp.h>
27 
28 /*
29  * Mibs are stored in array of unsigned long.
30  */
31 /*
32  * struct snmp_mib{}
33  *  - list of entries for particular API (such as /proc/net/snmp)
34  *  - name of entries.
35  */
36 struct snmp_mib {
37 	char *name;
38 	int entry;
39 };
40 
41 #define SNMP_MIB_ITEM(_name,_entry)	{	\
42 	.name = _name,				\
43 	.entry = _entry,			\
44 }
45 
46 #define SNMP_MIB_SENTINEL {	\
47 	.name = NULL,		\
48 	.entry = 0,		\
49 }
50 
51 /*
52  * We use all unsigned longs. Linux will soon be so reliable that even
53  * these will rapidly get too small 8-). Seriously consider the IpInReceives
54  * count on the 20Gb/s + networks people expect in a few years time!
55  */
56 
57 /*
58  * The rule for padding:
59  * Best is power of two because then the right structure can be found by a
60  * simple shift. The structure should be always cache line aligned.
61  * gcc needs n=alignto(cachelinesize, popcnt(sizeof(bla_mib))) shift/add
62  * instructions to emulate multiply in case it is not power-of-two.
63  * Currently n is always <=3 for all sizes so simple cache line alignment
64  * is enough.
65  *
66  * The best solution would be a global CPU local area , especially on 64
67  * and 128byte cacheline machine it makes a *lot* of sense -AK
68  */
69 
70 #define __SNMP_MIB_ALIGN__	____cacheline_aligned
71 
72 /* IPstats */
73 #define IPSTATS_MIB_MAX	__IPSTATS_MIB_MAX
74 struct ipstats_mib {
75 	unsigned long	mibs[IPSTATS_MIB_MAX];
76 } __SNMP_MIB_ALIGN__;
77 
78 /* ICMP */
79 #define ICMP_MIB_DUMMY	__ICMP_MIB_MAX
80 #define ICMP_MIB_MAX	(__ICMP_MIB_MAX + 1)
81 
82 struct icmp_mib {
83 	unsigned long	mibs[ICMP_MIB_MAX];
84 } __SNMP_MIB_ALIGN__;
85 
86 #define ICMPMSG_MIB_MAX	__ICMPMSG_MIB_MAX
87 struct icmpmsg_mib {
88 	unsigned long	mibs[ICMPMSG_MIB_MAX];
89 } __SNMP_MIB_ALIGN__;
90 
91 /* ICMP6 (IPv6-ICMP) */
92 #define ICMP6_MIB_MAX	__ICMP6_MIB_MAX
93 struct icmpv6_mib {
94 	unsigned long	mibs[ICMP6_MIB_MAX];
95 } __SNMP_MIB_ALIGN__;
96 
97 #define ICMP6MSG_MIB_MAX  __ICMP6MSG_MIB_MAX
98 struct icmpv6msg_mib {
99 	unsigned long	mibs[ICMP6MSG_MIB_MAX];
100 } __SNMP_MIB_ALIGN__;
101 
102 
103 /* TCP */
104 #define TCP_MIB_MAX	__TCP_MIB_MAX
105 struct tcp_mib {
106 	unsigned long	mibs[TCP_MIB_MAX];
107 } __SNMP_MIB_ALIGN__;
108 
109 /* UDP */
110 #define UDP_MIB_MAX	__UDP_MIB_MAX
111 struct udp_mib {
112 	unsigned long	mibs[UDP_MIB_MAX];
113 } __SNMP_MIB_ALIGN__;
114 
115 /* Linux */
116 #define LINUX_MIB_MAX	__LINUX_MIB_MAX
117 struct linux_mib {
118 	unsigned long	mibs[LINUX_MIB_MAX];
119 };
120 
121 /* Linux Xfrm */
122 #define LINUX_MIB_XFRMMAX	__LINUX_MIB_XFRMMAX
123 struct linux_xfrm_mib {
124 	unsigned long	mibs[LINUX_MIB_XFRMMAX];
125 };
126 
127 /*
128  * FIXME: On x86 and some other CPUs the split into user and softirq parts
129  * is not needed because addl $1,memory is atomic against interrupts (but
130  * atomic_inc would be overkill because of the lock cycles). Wants new
131  * nonlocked_atomic_inc() primitives -AK
132  */
133 #define DEFINE_SNMP_STAT(type, name)	\
134 	__typeof__(type) *name[2]
135 #define DECLARE_SNMP_STAT(type, name)	\
136 	extern __typeof__(type) *name[2]
137 
138 #define SNMP_STAT_BHPTR(name)	(name[0])
139 #define SNMP_STAT_USRPTR(name)	(name[1])
140 
141 #define SNMP_INC_STATS_BH(mib, field) 	\
142 	(per_cpu_ptr(mib[0], raw_smp_processor_id())->mibs[field]++)
143 #define SNMP_INC_STATS_USER(mib, field) \
144 	do { \
145 		per_cpu_ptr(mib[1], get_cpu())->mibs[field]++; \
146 		put_cpu(); \
147 	} while (0)
148 #define SNMP_INC_STATS(mib, field) 	\
149 	do { \
150 		per_cpu_ptr(mib[!in_softirq()], get_cpu())->mibs[field]++; \
151 		put_cpu(); \
152 	} while (0)
153 #define SNMP_DEC_STATS(mib, field) 	\
154 	do { \
155 		per_cpu_ptr(mib[!in_softirq()], get_cpu())->mibs[field]--; \
156 		put_cpu(); \
157 	} while (0)
158 #define SNMP_ADD_STATS_BH(mib, field, addend) 	\
159 	(per_cpu_ptr(mib[0], raw_smp_processor_id())->mibs[field] += addend)
160 #define SNMP_ADD_STATS_USER(mib, field, addend) 	\
161 	do { \
162 		per_cpu_ptr(mib[1], get_cpu())->mibs[field] += addend; \
163 		put_cpu(); \
164 	} while (0)
165 
166 #endif
167