xref: /openbmc/linux/include/net/snmp.h (revision 4800cd83)
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 	const 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 unsigned longs for most mibs but u64 for ipstats.
51  */
52 #include <linux/u64_stats_sync.h>
53 
54 /* IPstats */
55 #define IPSTATS_MIB_MAX	__IPSTATS_MIB_MAX
56 struct ipstats_mib {
57 	/* mibs[] must be first field of struct ipstats_mib */
58 	u64		mibs[IPSTATS_MIB_MAX];
59 	struct u64_stats_sync syncp;
60 };
61 
62 /* ICMP */
63 #define ICMP_MIB_MAX	__ICMP_MIB_MAX
64 struct icmp_mib {
65 	unsigned long	mibs[ICMP_MIB_MAX];
66 };
67 
68 #define ICMPMSG_MIB_MAX	__ICMPMSG_MIB_MAX
69 struct icmpmsg_mib {
70 	unsigned long	mibs[ICMPMSG_MIB_MAX];
71 };
72 
73 /* ICMP6 (IPv6-ICMP) */
74 #define ICMP6_MIB_MAX	__ICMP6_MIB_MAX
75 struct icmpv6_mib {
76 	unsigned long	mibs[ICMP6_MIB_MAX];
77 };
78 
79 #define ICMP6MSG_MIB_MAX  __ICMP6MSG_MIB_MAX
80 struct icmpv6msg_mib {
81 	unsigned long	mibs[ICMP6MSG_MIB_MAX];
82 };
83 
84 
85 /* TCP */
86 #define TCP_MIB_MAX	__TCP_MIB_MAX
87 struct tcp_mib {
88 	unsigned long	mibs[TCP_MIB_MAX];
89 };
90 
91 /* UDP */
92 #define UDP_MIB_MAX	__UDP_MIB_MAX
93 struct udp_mib {
94 	unsigned long	mibs[UDP_MIB_MAX];
95 };
96 
97 /* Linux */
98 #define LINUX_MIB_MAX	__LINUX_MIB_MAX
99 struct linux_mib {
100 	unsigned long	mibs[LINUX_MIB_MAX];
101 };
102 
103 /* Linux Xfrm */
104 #define LINUX_MIB_XFRMMAX	__LINUX_MIB_XFRMMAX
105 struct linux_xfrm_mib {
106 	unsigned long	mibs[LINUX_MIB_XFRMMAX];
107 };
108 
109 /*
110  * FIXME: On x86 and some other CPUs the split into user and softirq parts
111  * is not needed because addl $1,memory is atomic against interrupts (but
112  * atomic_inc would be overkill because of the lock cycles). Wants new
113  * nonlocked_atomic_inc() primitives -AK
114  */
115 #define DEFINE_SNMP_STAT(type, name)	\
116 	__typeof__(type) __percpu *name[2]
117 #define DECLARE_SNMP_STAT(type, name)	\
118 	extern __typeof__(type) __percpu *name[2]
119 
120 #define SNMP_STAT_BHPTR(name)	(name[0])
121 #define SNMP_STAT_USRPTR(name)	(name[1])
122 
123 #define SNMP_INC_STATS_BH(mib, field)	\
124 			__this_cpu_inc(mib[0]->mibs[field])
125 #define SNMP_INC_STATS_USER(mib, field)	\
126 			this_cpu_inc(mib[1]->mibs[field])
127 #define SNMP_INC_STATS(mib, field)	\
128 			this_cpu_inc(mib[!in_softirq()]->mibs[field])
129 #define SNMP_DEC_STATS(mib, field)	\
130 			this_cpu_dec(mib[!in_softirq()]->mibs[field])
131 #define SNMP_ADD_STATS_BH(mib, field, addend)	\
132 			__this_cpu_add(mib[0]->mibs[field], addend)
133 #define SNMP_ADD_STATS_USER(mib, field, addend)	\
134 			this_cpu_add(mib[1]->mibs[field], addend)
135 #define SNMP_ADD_STATS(mib, field, addend)	\
136 			this_cpu_add(mib[!in_softirq()]->mibs[field], addend)
137 /*
138  * Use "__typeof__(*mib[0]) *ptr" instead of "__typeof__(mib[0]) ptr"
139  * to make @ptr a non-percpu pointer.
140  */
141 #define SNMP_UPD_PO_STATS(mib, basefield, addend)	\
142 	do { \
143 		__typeof__(*mib[0]) *ptr; \
144 		preempt_disable(); \
145 		ptr = this_cpu_ptr((mib)[!in_softirq()]); \
146 		ptr->mibs[basefield##PKTS]++; \
147 		ptr->mibs[basefield##OCTETS] += addend;\
148 		preempt_enable(); \
149 	} while (0)
150 #define SNMP_UPD_PO_STATS_BH(mib, basefield, addend)	\
151 	do { \
152 		__typeof__(*mib[0]) *ptr = \
153 			__this_cpu_ptr((mib)[!in_softirq()]); \
154 		ptr->mibs[basefield##PKTS]++; \
155 		ptr->mibs[basefield##OCTETS] += addend;\
156 	} while (0)
157 
158 
159 #if BITS_PER_LONG==32
160 
161 #define SNMP_ADD_STATS64_BH(mib, field, addend) 			\
162 	do {								\
163 		__typeof__(*mib[0]) *ptr = __this_cpu_ptr((mib)[0]);	\
164 		u64_stats_update_begin(&ptr->syncp);			\
165 		ptr->mibs[field] += addend;				\
166 		u64_stats_update_end(&ptr->syncp);			\
167 	} while (0)
168 #define SNMP_ADD_STATS64_USER(mib, field, addend) 			\
169 	do {								\
170 		__typeof__(*mib[0]) *ptr;				\
171 		preempt_disable();					\
172 		ptr = __this_cpu_ptr((mib)[1]);				\
173 		u64_stats_update_begin(&ptr->syncp);			\
174 		ptr->mibs[field] += addend;				\
175 		u64_stats_update_end(&ptr->syncp);			\
176 		preempt_enable();					\
177 	} while (0)
178 #define SNMP_ADD_STATS64(mib, field, addend)				\
179 	do {								\
180 		__typeof__(*mib[0]) *ptr;				\
181 		preempt_disable();					\
182 		ptr = __this_cpu_ptr((mib)[!in_softirq()]);		\
183 		u64_stats_update_begin(&ptr->syncp);			\
184 		ptr->mibs[field] += addend;				\
185 		u64_stats_update_end(&ptr->syncp);			\
186 		preempt_enable();					\
187 	} while (0)
188 #define SNMP_INC_STATS64_BH(mib, field) SNMP_ADD_STATS64_BH(mib, field, 1)
189 #define SNMP_INC_STATS64_USER(mib, field) SNMP_ADD_STATS64_USER(mib, field, 1)
190 #define SNMP_INC_STATS64(mib, field) SNMP_ADD_STATS64(mib, field, 1)
191 #define SNMP_UPD_PO_STATS64(mib, basefield, addend)			\
192 	do {								\
193 		__typeof__(*mib[0]) *ptr;				\
194 		preempt_disable();					\
195 		ptr = __this_cpu_ptr((mib)[!in_softirq()]);		\
196 		u64_stats_update_begin(&ptr->syncp);			\
197 		ptr->mibs[basefield##PKTS]++;				\
198 		ptr->mibs[basefield##OCTETS] += addend;			\
199 		u64_stats_update_end(&ptr->syncp);			\
200 		preempt_enable();					\
201 	} while (0)
202 #define SNMP_UPD_PO_STATS64_BH(mib, basefield, addend)			\
203 	do {								\
204 		__typeof__(*mib[0]) *ptr;				\
205 		ptr = __this_cpu_ptr((mib)[!in_softirq()]);		\
206 		u64_stats_update_begin(&ptr->syncp);			\
207 		ptr->mibs[basefield##PKTS]++;				\
208 		ptr->mibs[basefield##OCTETS] += addend;			\
209 		u64_stats_update_end(&ptr->syncp);			\
210 	} while (0)
211 #else
212 #define SNMP_INC_STATS64_BH(mib, field)		SNMP_INC_STATS_BH(mib, field)
213 #define SNMP_INC_STATS64_USER(mib, field)	SNMP_INC_STATS_USER(mib, field)
214 #define SNMP_INC_STATS64(mib, field)		SNMP_INC_STATS(mib, field)
215 #define SNMP_DEC_STATS64(mib, field)		SNMP_DEC_STATS(mib, field)
216 #define SNMP_ADD_STATS64_BH(mib, field, addend) SNMP_ADD_STATS_BH(mib, field, addend)
217 #define SNMP_ADD_STATS64_USER(mib, field, addend) SNMP_ADD_STATS_USER(mib, field, addend)
218 #define SNMP_ADD_STATS64(mib, field, addend)	SNMP_ADD_STATS(mib, field, addend)
219 #define SNMP_UPD_PO_STATS64(mib, basefield, addend) SNMP_UPD_PO_STATS(mib, basefield, addend)
220 #define SNMP_UPD_PO_STATS64_BH(mib, basefield, addend) SNMP_UPD_PO_STATS_BH(mib, basefield, addend)
221 #endif
222 
223 #endif
224