Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/include/net/snmp.h b/include/net/snmp.h
new file mode 100644
index 0000000..a15ab25
--- /dev/null
+++ b/include/net/snmp.h
@@ -0,0 +1,145 @@
+/*
+ *
+ *		SNMP MIB entries for the IP subsystem.
+ *		
+ *		Alan Cox <gw4pts@gw4pts.ampr.org>
+ *
+ *		We don't chose to implement SNMP in the kernel (this would
+ *		be silly as SNMP is a pain in the backside in places). We do
+ *		however need to collect the MIB statistics and export them
+ *		out of /proc (eventually)
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ *		$Id: snmp.h,v 1.19 2001/06/14 13:40:46 davem Exp $
+ *
+ */
+ 
+#ifndef _SNMP_H
+#define _SNMP_H
+
+#include <linux/cache.h>
+#include <linux/snmp.h>
+
+/*
+ * Mibs are stored in array of unsigned long.
+ */
+/*
+ * struct snmp_mib{}
+ *  - list of entries for particular API (such as /proc/net/snmp)
+ *  - name of entries.
+ */
+struct snmp_mib {
+	char *name;
+	int entry;
+};
+
+#define SNMP_MIB_ITEM(_name,_entry)	{	\
+	.name = _name,				\
+	.entry = _entry,			\
+}
+
+#define SNMP_MIB_SENTINEL {	\
+	.name = NULL,		\
+	.entry = 0,		\
+}
+
+/*
+ * We use all unsigned longs. Linux will soon be so reliable that even 
+ * these will rapidly get too small 8-). Seriously consider the IpInReceives 
+ * count on the 20Gb/s + networks people expect in a few years time!
+ */
+
+/* 
+ * The rule for padding: 
+ * Best is power of two because then the right structure can be found by a 
+ * simple shift. The structure should be always cache line aligned.
+ * gcc needs n=alignto(cachelinesize, popcnt(sizeof(bla_mib))) shift/add 
+ * instructions to emulate multiply in case it is not power-of-two. 
+ * Currently n is always <=3 for all sizes so simple cache line alignment 
+ * is enough. 
+ * 
+ * The best solution would be a global CPU local area , especially on 64 
+ * and 128byte cacheline machine it makes a *lot* of sense -AK
+ */ 
+
+#define __SNMP_MIB_ALIGN__	____cacheline_aligned
+
+/* IPstats */
+#define IPSTATS_MIB_MAX	__IPSTATS_MIB_MAX
+struct ipstats_mib {
+	unsigned long	mibs[IPSTATS_MIB_MAX];
+} __SNMP_MIB_ALIGN__;
+
+/* ICMP */
+#define ICMP_MIB_DUMMY	__ICMP_MIB_MAX
+#define ICMP_MIB_MAX	(__ICMP_MIB_MAX + 1)
+
+struct icmp_mib {
+	unsigned long	mibs[ICMP_MIB_MAX];
+} __SNMP_MIB_ALIGN__;
+
+/* ICMP6 (IPv6-ICMP) */
+#define ICMP6_MIB_MAX	__ICMP6_MIB_MAX
+struct icmpv6_mib {
+	unsigned long	mibs[ICMP6_MIB_MAX];
+} __SNMP_MIB_ALIGN__;
+
+/* TCP */
+#define TCP_MIB_MAX	__TCP_MIB_MAX
+struct tcp_mib {
+	unsigned long	mibs[TCP_MIB_MAX];
+} __SNMP_MIB_ALIGN__;
+
+/* UDP */
+#define UDP_MIB_MAX	__UDP_MIB_MAX
+struct udp_mib {
+	unsigned long	mibs[UDP_MIB_MAX];
+} __SNMP_MIB_ALIGN__;
+
+/* SCTP */
+#define SCTP_MIB_MAX	__SCTP_MIB_MAX
+struct sctp_mib {
+	unsigned long	mibs[SCTP_MIB_MAX];
+} __SNMP_MIB_ALIGN__;
+
+/* Linux */
+#define LINUX_MIB_MAX	__LINUX_MIB_MAX
+struct linux_mib {
+	unsigned long	mibs[LINUX_MIB_MAX];
+};
+
+
+/* 
+ * FIXME: On x86 and some other CPUs the split into user and softirq parts
+ * is not needed because addl $1,memory is atomic against interrupts (but 
+ * atomic_inc would be overkill because of the lock cycles). Wants new 
+ * nonlocked_atomic_inc() primitives -AK
+ */ 
+#define DEFINE_SNMP_STAT(type, name)	\
+	__typeof__(type) *name[2]
+#define DECLARE_SNMP_STAT(type, name)	\
+	extern __typeof__(type) *name[2]
+
+#define SNMP_STAT_BHPTR(name)	(name[0])
+#define SNMP_STAT_USRPTR(name)	(name[1])
+
+#define SNMP_INC_STATS_BH(mib, field) 	\
+	(per_cpu_ptr(mib[0], _smp_processor_id())->mibs[field]++)
+#define SNMP_INC_STATS_OFFSET_BH(mib, field, offset)	\
+	(per_cpu_ptr(mib[0], _smp_processor_id())->mibs[field + (offset)]++)
+#define SNMP_INC_STATS_USER(mib, field) \
+	(per_cpu_ptr(mib[1], _smp_processor_id())->mibs[field]++)
+#define SNMP_INC_STATS(mib, field) 	\
+	(per_cpu_ptr(mib[!in_softirq()], _smp_processor_id())->mibs[field]++)
+#define SNMP_DEC_STATS(mib, field) 	\
+	(per_cpu_ptr(mib[!in_softirq()], _smp_processor_id())->mibs[field]--)
+#define SNMP_ADD_STATS_BH(mib, field, addend) 	\
+	(per_cpu_ptr(mib[0], _smp_processor_id())->mibs[field] += addend)
+#define SNMP_ADD_STATS_USER(mib, field, addend) 	\
+	(per_cpu_ptr(mib[1], _smp_processor_id())->mibs[field] += addend)
+
+#endif