[PATCH 2/4] Per IP network statistics: hash table implementation
From: Menny Hamburger
Date: Tue Sep 03 2013 - 03:52:28 EST
diff -r -U 4 a/include/linux/sysctl.h b/include/linux/sysctl.h
--- a/include/linux/sysctl.h 2013-09-02 12:44:17.415733555 +0300
+++ b/include/linux/sysctl.h 2013-09-02 12:44:17.537622128 +0300
@@ -436,8 +436,16 @@
NET_TCP_FRTO_RESPONSE=125,
#ifdef CONFIG_NET_IPV4_SNMP_MAPPING
NET_IPV4_SNMP_MAP_LEVEL=150,
#endif
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+ NET_IPV4_STAT_HASHTABLE_ENABLE=151,
+ NET_IPV4_STAT_HASHTABLE_DEBUG_LEVEL=152,
+ NET_IPV4_STAT_HASHTABLE_LOOPBACK=153,
+ NET_IPV4_STAT_HASHTABLE_DELETE=154,
+ NET_IPV4_STAT_HASHTABLE_ZERO=155,
+ NET_IPV4_STAT_HASHTABLE_MAX=156,
+#endif
};
enum {
NET_IPV4_ROUTE_FLUSH=1,
@@ -592,8 +600,13 @@
NET_IPV6_RTR_PROBE_INTERVAL=21,
NET_IPV6_ACCEPT_RA_RT_INFO_MAX_PLEN=22,
NET_IPV6_PROXY_NDP=23,
NET_IPV6_ACCEPT_SOURCE_ROUTE=25,
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ NET_IPV6_STAT_HASHTABLE_ENABLE=50,
+ NET_IPV6_STAT_HASHTABLE_DELETE=51,
+ NET_IPV6_STAT_HASHTABLE_ZERO=52,
+#endif
__NET_IPV6_MAX
};
/* /proc/sys/net/ipv6/icmp */
diff -r -U 4 a/include/net/stat_hashtable_cookie.h b/include/net/stat_hashtable_cookie.h
--- a/include/net/stat_hashtable_cookie.h 2013-09-02 12:44:17.425622445 +0300
+++ b/include/net/stat_hashtable_cookie.h 2013-09-02 12:44:17.553639794 +0300
@@ -0,0 +1,67 @@
+#ifndef _STAT_HASHTABLE_COOKIE_H
+#define _STAT_HASHTABLE_COOKIE_H
+
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+
+struct stat_hash_cookie {
+ struct {
+ u16 family;
+ u16 bucket;
+ } hash;
+ atomic_t seq;
+};
+
+static inline void
+stat_hash_init_cookie(struct stat_hash_cookie *cookie)
+{
+ memset(cookie, 0, sizeof(struct stat_hash_cookie));
+}
+
+#define STAT_INIT_COOKIE(cookie) stat_hash_init_cookie(cookie)
+
+static inline void
+stat_hash_copy_cookie(struct stat_hash_cookie *tgt, struct stat_hash_cookie *src)
+{
+ memcpy(tgt, src, sizeof(struct stat_hash_cookie));
+}
+
+static inline void
+stat_hash_copy_cookie_atomic(struct stat_hash_cookie *tgt, struct stat_hash_cookie *src)
+{
+ tgt->hash.family = src->hash.family;
+ tgt->hash.bucket = src->hash.bucket;
+ smp_mb();
+ atomic_set(&tgt->seq, src->seq.counter);
+ smp_mb();
+}
+
+#define STAT_COOKIE_POLLUTE_NOENT (INT_MAX)
+
+static inline bool
+stat_hash_cookie_useable(struct stat_hash_cookie *cookie)
+{
+ u32 value = ((cookie != NULL) ? cookie->seq.counter : 0);
+
+ return (value && (value != STAT_COOKIE_POLLUTE_NOENT));
+}
+
+static inline void
+stat_hash_cookie_pollute(struct stat_hash_cookie *cookie, int code)
+{
+ smp_mb();
+ atomic_set(&cookie->seq, code);
+ smp_mb();
+}
+
+/* We use memory barriers to setup the cookie so we don't have to use atomics (locking) */
+#define STAT_COOKIE_EMPTY(cookie) \
+ ((cookie)->seq.counter == 0)
+
+#else
+
+#define STAT_INIT_COOKIE(cookie)
+
+#endif
+
+#endif
+
diff -r -U 4 a/include/net/stat_hashtable.h b/include/net/stat_hashtable.h
--- a/include/net/stat_hashtable.h 2013-09-02 12:44:17.432630047 +0300
+++ b/include/net/stat_hashtable.h 2013-09-02 12:44:17.569622398 +0300
@@ -0,0 +1,565 @@
+/*
+ * Per-ip statistics hashtable implmentation
+ *
+ * Menny Hamburger<menny_hamburger@xxxxxxxx>
+ */
+
+#ifndef _STAT_HASHMAP_H
+#define _STAT_HASHMAP_H
+
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+
+#include <linux/jhash.h>
+#include <net/snmp_map.h>
+#include <net/stat_hashtable_cookie.h>
+
+
+extern bool stat_hash_data_collection_started;
+extern int stat_hash_start_data_collection(void);
+extern void stat_hash_stop_data_collection(void);
+
+/*
+ * Macros used for updating the statistics counters by use of a previousely stored cookie.
+ * Use of a cookie reduces CPU cycles by eliminating the need to call jhash when we need to update the counters
+ * contained in a hashtable entry (the cookie includes the bucket in which the entry is stored).
+ */
+#define MAP_FROM_COOKIE(cookie, m, field) \
+ struct snmp_mib_map *map = ((stat_hash_cookie_useable(cookie) ? stat_hash_##m##_ptr(cookie, field) : NULL))
+
+
+#define SNMP_INC_STATS_HASH_BH(cookie, m, field) \
+ do { \
+ MAP_FROM_COOKIE(cookie, m, field); \
+ SNMP_INC_STATS_MAPPING_BH(map, field); \
+ } while (0)
+#define SNMP_INC_STATS_HASH_USER(cookie, m, field) \
+ do { \
+ MAP_FROM_COOKIE(cookie, m, field); \
+ SNMP_INC_STATS_MAPPING_USER(map, field); \
+ } while (0)
+#define SNMP_INC_STATS_HASH(cookie, m, field) \
+ do { \
+ MAP_FROM_COOKIE(cookie, m, field); \
+ SNMP_INC_STATS_MAPPING(map, field); \
+ } while (0)
+#define SNMP_DEC_STATS_HASH(cookie, m, field) \
+ do { \
+ MAP_FROM_COOKIE(cookie, m, field); \
+ SNMP_DEC_STATS_MAPPING(map, field); \
+ } while (0)
+#define SNMP_ADD_STATS_HASH(cookie, m, field, addend) \
+ do { \
+ MAP_FROM_COOKIE(cookie, m, field); \
+ SNMP_ADD_STATS_MAPPING(map, field, addend); \
+ } while (0)
+#define SNMP_ADD_STATS_HASH_BH(cookie, m, field, addend) \
+ do { \
+ MAP_FROM_COOKIE(cookie, m, field); \
+ SNMP_ADD_STATS_MAPPING_BH(map, field, addend); \
+ } while (0)
+#define SNMP_ADD_STATS_HASH_USER(cookie, m, field, addend) \
+ do { \
+ MAP_FROM_COOKIE(cookie, m, field); \
+ SNMP_ADD_STATS_MAPPING_USER(map, field, addend); \
+ } while (0)
+
+/*
+ * Address definitions used for accessing the hash table.
+ * The address is used both when inserting a new entry into the hash (supplying a cookie to the caller),
+ * or when we need to update the counters contained in a hash entry and don't have a cookie.
+ */
+union stat_hash_inet_addr {
+ __be32 ip;
+ struct in_addr in;
+ __be32 ip6[4];
+ struct in6_addr in6;
+};
+
+struct stat_hash_addr {
+ u16 family;
+ union stat_hash_inet_addr saddr;
+ union stat_hash_inet_addr daddr;
+};
+
+/* Macros used for updating the statistics counters by supplying an address */
+#define MAP_FROM_ADDRESS(initval, addr, m, field) \
+ struct snmp_mib_map *map = stat_hash_##m##_ptr_from_address(initval, addr, field)
+
+#define SNMP_INC_STATS_HASH_ADDR_BH(initval, addr, m, field) \
+ do { \
+ MAP_FROM_ADDRESS(initval, addr, m, field); \
+ SNMP_INC_STATS_MAPPING_BH(map, field); \
+ } while (0)
+#define SNMP_INC_STATS_HASH_ADDR_USER(initval, addr, m, field) \
+ do { \
+ MAP_FROM_ADDRESS(initval, addr, m, field); \
+ SNMP_INC_STATS_MAPPING_USER(map, field); \
+ } while (0)
+#define SNMP_INC_STATS_HASH_ADDR(initval, addr, m, field) \
+ do { \
+ MAP_FROM_ADDRESS(initval, addr, m, field); \
+ SNMP_INC_STATS_MAPPING(map, field); \
+ } while (0)
+#define SNMP_DEC_STATS_HASH_ADDR(initval, addr, m, field) \
+ do { \
+ MAP_FROM_ADDRESS(initval, addr, m, field); \
+ SNMP_DEC_STATS_MAPPING(map, field); \
+ } while (0)
+#define SNMP_ADD_STATS_HASH_ADDR(initval, addr, m, field, addend) \
+ do { \
+ MAP_FROM_ADDRESS(initval, addr, m, field); \
+ SNMP_ADD_STATS_MAPPING(map, field, addend); \
+ } while (0)
+#define SNMP_ADD_STATS_HASH_ADDR_BH(addr, m, field, addend) \
+ do { \
+ MAP_FROM_ADDRESS(initval, addr, m, field); \
+ SNMP_ADD_STATS_MAPPING_BH(map, field, addend); \
+ } while (0)
+#define SNMP_ADD_STATS_HASH_ADDR_USER(initval, addr, m, field, addend) \
+ do { \
+ MAP_FROM_ADDRESS(initval, addr, m, field); \
+ SNMP_ADD_STATS_MAPPING_USER(map, field, addend); \
+ } while (0)
+
+
+/* Available values for state member of stat_hash_entry_mappings */
+enum {
+ STAT_HASH_MAPPING_STATE_NEW,
+ STAT_HASH_MAPPING_STATE_ENTRY,
+ STAT_HASH_MAPPING_STATE_ALLOCATING,
+ STAT_HASH_MAPPING_STATE_ALLOCATED,
+};
+
+struct stat_hash_entry_mappings;
+/* delayed work section of an entry, used for allocating the per CPU counters lazily if necassary */
+struct state_hash_entry_delayed {
+ struct stat_hash_entry_mappings *mapping;
+ struct delayed_work alloc_work;
+};
+
+/* Data structure for storing counters of single mapping level */
+struct stat_hash_entry_mappings {
+ atomic_t state;
+ /* We are only interested in TCP statistics for now */
+ DEFINE_SNMP_MIB_MAP(struct tcp_mib_map, tcp_stats);
+ DEFINE_SNMP_MIB_MAP(struct linux_mib_map, lnx_stats);
+ struct state_hash_entry_delayed *delayed;
+};
+
+struct stat_hash_entry {
+ struct hlist_node hlist;
+ struct rcu_head rcu;
+
+ /* A sequence number used for identifying the entry using a previousely stored cookie */
+ u32 sequence;
+
+ /* The contained address */
+ struct stat_hash_addr addr;
+
+ /* the actual mappings that countain the per CPU counters for every available SNMP map level */
+ struct stat_hash_entry_mappings mappings[SNMP_MAP_LEVEL_MAX];
+};
+
+struct stat_hash_lookup_info {
+ int len;
+ /*
+ * Sequence number assigned to the entry with the lowest number in the hashtable.
+ * When hashtable is emptied and the entries are deleted using proc interface, this is updated.
+ * If the sequence number specified in a cookie is less than then the value of this, it can only mean
+ * that the hashtable was emptied at at least once (using the proc interface) and the entry we are looking
+ * for does not exist.
+ */
+ u32 first_sequence;
+ struct hlist_head *htable;
+};
+
+enum {
+ STAT_HASH_IPV4_INFO,
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ STAT_HASH_IPV6_INFO,
+#endif
+ STAT_HASH_INFO_MAX,
+};
+
+extern struct stat_hash_lookup_info *stat_lookup_info[STAT_HASH_INFO_MAX];
+
+static inline struct stat_hash_lookup_info *
+stat_hash_get_lookup_info(u16 family)
+{
+ struct stat_hash_lookup_info *info = NULL;
+
+ switch (family) {
+ case AF_INET:
+ info = stat_lookup_info[STAT_HASH_IPV4_INFO];
+ break;
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ case AF_INET6:
+ info = stat_lookup_info[STAT_HASH_IPV6_INFO];
+ break;
+#endif
+ default:
+ break;
+ }
+
+ return info;
+}
+
+static inline struct snmp_mib_map *
+stat_hash_get_mapping(struct stat_hash_entry_mappings *mapping, u8 mibid)
+{
+ struct snmp_mib_map *map = NULL;
+
+ switch (mibid) {
+ case SNMP_TCP_MIB:
+ map = (struct snmp_mib_map *) &mapping->tcp_stats;
+ break;
+ case SNMP_LINUX_MIB:
+ map = (struct snmp_mib_map *) &mapping->lnx_stats;
+ break;
+ default:
+ break;
+ }
+
+ return map;
+}
+
+static inline bool
+stat_hash_mapping_state_equals(struct stat_hash_entry_mappings *mapping, int state)
+{
+ return (state == atomic_read(&mapping->state));
+}
+
+static inline bool
+stat_hash_mapping_state_equals_nonatomic(struct stat_hash_entry_mappings *mapping, int state)
+{
+ return (state == mapping->state.counter);
+}
+
+static inline bool
+stat_hash_mapping_state(struct stat_hash_entry *entry, int maplvl, int state)
+{
+ return stat_hash_mapping_state_equals(&entry->mappings[maplvl], state);
+}
+
+static inline bool
+stat_hash_mapping_state_nonatomic(struct stat_hash_entry *entry, int maplvl, int state)
+{
+ return stat_hash_mapping_state_equals_nonatomic(&entry->mappings[maplvl], state);
+}
+
+static inline bool
+stat_hash_mapping_allocated(struct stat_hash_entry *entry, int maplvl)
+{
+ return stat_hash_mapping_state(entry, maplvl, STAT_HASH_MAPPING_STATE_ALLOCATED);
+}
+
+/* Non atomic version for use in lookup */
+static inline bool
+stat_hash_mapping_allocated_nonatomic(struct stat_hash_entry *entry, int maplvl)
+{
+ return stat_hash_mapping_state_nonatomic(entry, maplvl, STAT_HASH_MAPPING_STATE_ALLOCATED);
+}
+
+static inline bool
+stat_hash_any_allocated(struct stat_hash_entry *entry)
+{
+ int i;
+
+ for (i = 0; i < SNMP_MAP_LEVEL_MAX; i++) {
+ if (stat_hash_mapping_allocated(entry, i))
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * Lookup function for accessing a hash entry using a previousely stored cookie.
+ * This is the preferred method for accessing the hashtables and should be used always
+ * unless we don't have access to a cookie.
+ */
+static inline struct snmp_mib_map *
+stat_hash_lookup_by_cookie(struct stat_hash_cookie *cookie, u8 mibid, u8 field)
+{
+ struct stat_hash_lookup_info *info;
+ struct stat_hash_entry *entry = NULL;
+ struct hlist_head *head;
+ struct hlist_node *pos;
+
+ info = stat_hash_get_lookup_info(cookie->hash.family);
+ if (info == NULL)
+ return NULL;
+
+ /*
+ * If the requested entry was deleted from the hashtable, we want the container to stop using the cookie for looking up
+ * the hash entry, or in other words we want to pollute the cookie so it will no longer be used.
+ */
+ if (cookie->seq.counter < info->first_sequence) {
+ stat_hash_cookie_pollute(cookie, STAT_COOKIE_POLLUTE_NOENT);
+ return NULL;
+ }
+
+ head = &info->htable[cookie->hash.bucket];
+ hlist_for_each_entry_rcu(entry, pos, head, hlist) {
+ if (entry->sequence == cookie->seq.counter) {
+ int maplvl = snmp_map_get_map_level(mibid, field);
+ if ((maplvl != SNMP_MAP_UNMAPPED) && stat_hash_mapping_allocated_nonatomic(entry, maplvl)) {
+ return stat_hash_get_mapping(&entry->mappings[maplvl], mibid);
+ }
+ }
+ }
+
+ return NULL;
+}
+
+
+/*************************************************************************************
+ * Helper functions for looking up an entry in the hashtable by address
+ *************************************************************************************/
+
+
+static inline u16 stat4_ehashfn(u16 sz, u32 initval, struct stat_hash_addr *addr)
+{
+ return jhash_2words(addr->saddr.ip, addr->daddr.ip, initval) & (sz - 1);
+}
+
+
+static inline void
+stat4_reverse_address(struct stat_hash_addr *tgt, struct stat_hash_addr *src)
+{
+ tgt->saddr.ip = src->daddr.ip;
+ tgt->daddr.ip = src->saddr.ip;
+}
+
+static inline bool
+stat4_compare_entry_addr(struct stat_hash_entry *entry, struct stat_hash_addr *addr)
+{
+ return (entry->addr.saddr.ip == addr->saddr.ip) && (entry->addr.daddr.ip == addr->daddr.ip);
+}
+
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+static inline u16
+stat6_ehashfn(u16 sz, u32 initval, struct stat_hash_addr *addr)
+{
+ u32 key[4];
+
+ key[0] = (__force u32)(&addr->saddr.in6)->s6_addr32[2];
+ key[1] = (__force u32)(&addr->saddr.in6)->s6_addr32[3];
+ key[2] = (__force u32)(&addr->daddr.in6)->s6_addr32[2];
+ key[3] = (__force u32)(&addr->daddr.in6)->s6_addr32[3];
+
+ return jhash2(key, 4, initval) & (sz - 1);
+}
+
+static inline void
+stat6_reverse_address(struct stat_hash_addr *tgt, struct stat_hash_addr *src)
+{
+ ipv6_addr_copy(&tgt->saddr.in6, &src->daddr.in6);
+ ipv6_addr_copy(&tgt->daddr.in6, &src->saddr.in6);
+}
+
+static inline bool
+stat6_compare_entry_addr(struct stat_hash_entry *entry, struct stat_hash_addr *addr)
+{
+ return ((ipv6_addr_equal(&entry->addr.saddr.in6, &addr->saddr.in6) &&
+ ipv6_addr_equal(&entry->addr.daddr.in6, &addr->daddr.in6)));
+}
+#endif
+
+static inline u16
+stat_hash_bucket(int len, u32 initval, struct stat_hash_addr *addr)
+{
+ if (addr->family == AF_INET)
+ return stat4_ehashfn(len, initval, addr);
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ else
+ return stat6_ehashfn(len, initval, addr);
+#endif
+}
+
+static inline bool
+stat_hash_match(struct stat_hash_entry *entry, struct stat_hash_addr *addr)
+{
+ if (addr->family == AF_INET)
+ return stat4_compare_entry_addr(entry, addr);
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ else
+ return stat6_compare_entry_addr(entry, addr);
+#endif
+}
+
+static inline void
+stat_hash_reverse_address(struct stat_hash_addr *tgt, struct stat_hash_addr *src)
+{
+ tgt->family = src->family;
+ if (src->family == AF_INET)
+ stat4_reverse_address(tgt, src);
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ else
+ stat6_reverse_address(tgt, src);
+#endif
+}
+
+static inline struct stat_hash_entry *
+stat_hash_lookup_addr(u32 initval, struct stat_hash_addr *addr, u16 *bucket_in)
+{
+ struct stat_hash_lookup_info *info;
+ struct hlist_head *head;
+ struct hlist_node *pos;
+ struct stat_hash_entry *entry;
+ struct stat_hash_addr raddr;
+ u16 bucket;
+
+ info = stat_hash_get_lookup_info(addr->family);
+ if (info == NULL)
+ return NULL;
+
+ bucket = stat_hash_bucket(info->len, initval, addr);
+ if (bucket_in != NULL)
+ *bucket_in = bucket;
+
+ head = &info->htable[bucket];
+ hlist_for_each_entry_rcu(entry, pos, head, hlist) {
+ if (stat_hash_match(entry, addr))
+ return entry;
+ }
+
+ /* There is a single hash entry for both in and out traffic */
+ stat_hash_reverse_address(&raddr, addr);
+ bucket = stat_hash_bucket(info->len, initval, &raddr);
+ if (bucket_in != NULL)
+ *bucket_in = bucket;
+
+ head = &info->htable[bucket];
+ hlist_for_each_entry_rcu(entry, pos, head, hlist) {
+ if (stat_hash_match(entry, &raddr))
+ return entry;
+ }
+
+ return NULL;
+}
+
+
+
+/*
+ * Lookup function for accessing a hash entry using an address.
+ * This method uses jhash for recomputing the hash bucket using a suppliyed address,
+ * thus tskes some more cpu and should only be used if we don't have a cookie to work with.
+ */
+static inline struct snmp_mib_map *
+stat_hash_lookup_by_address(int initval, struct stat_hash_addr *addr, u8 mibid, u8 field)
+{
+ struct stat_hash_entry *entry = NULL;
+
+ entry = stat_hash_lookup_addr(initval, addr, NULL);
+ if (entry) {
+ int maplvl = snmp_map_get_map_level(mibid, field);
+ if ((maplvl != SNMP_MAP_UNMAPPED) && stat_hash_mapping_allocated_nonatomic(entry, maplvl)) {
+ return stat_hash_get_mapping(&entry->mappings[maplvl], mibid);
+ }
+ }
+
+ return NULL;
+}
+
+/* Helper function to access specific SNMP MIB statistics in the hash entry by cookie */
+static inline struct snmp_mib_map *
+stat_hash_tcp_stats_ptr(struct stat_hash_cookie *cookie, u8 field)
+{
+ return stat_hash_lookup_by_cookie(cookie, SNMP_TCP_MIB, field);
+}
+
+static inline struct snmp_mib_map *
+stat_hash_lnx_stats_ptr(struct stat_hash_cookie *cookie, u8 field)
+{
+ return stat_hash_lookup_by_cookie(cookie, SNMP_LINUX_MIB, field);
+}
+
+/* Helper function to access specific SNMP MIB statistics in the hash entry by address */
+static inline struct snmp_mib_map *
+stat_hash_tcp_stats_ptr_from_address(int initval, struct stat_hash_addr *addr, u8 field)
+{
+ return stat_hash_lookup_by_address(initval, addr, SNMP_TCP_MIB, field);
+}
+
+static inline struct snmp_mib_map *
+stat_hash_lnx_stats_ptr_from_address(int initval, struct stat_hash_addr *addr, u8 field)
+{
+ return stat_hash_lookup_by_address(initval, addr, SNMP_LINUX_MIB, field);
+}
+
+/* possible flags for alloc_flag argument to stat_hash_get_entry */
+enum {
+ /*
+ * If an entry containing the address does not exists - don't allocate a new one.
+ * If an entry does exists, don't try to add new mapping levels to it (sort of a "read only" flag).
+ */
+ STAT_HASH_ALLOC_FLAG_NOALLOC,
+ /*
+ * If an entry doesn't exists we will allocate it and add it to the hashtable,
+ * where the per CPU counters are allocated for all mappings up to snmp_map_level.
+ * If an entry exists, missing per CPU counters up to snmp_map_level will be allocated.
+ */
+ STAT_HASH_ALLOC_FLAG_ALLOC,
+ /*
+ * If an entry doesn't exists we will allocate it and add it to the hashtable,
+ * where the per CPU counters are allocated for all mappings up to snmp_map_level in delayed work.
+ */
+ STAT_HASH_ALLOC_FLAG_DELAYED_ALLOC,
+};
+
+/*
+ * Main entry point for inserting an entry containing a specified address into the statistics hashtable.
+ * Arguments:
+ * initval: used by jhash
+ * existing: were expecting an entry containing the address to exists, if it doesn't we do not try to allocate insert a new entry.
+ * alloc_flag: used for specifying how an entry per CPU counters should be allocated per mapping level (stat_hash_entry_mappings)
+ * SNMP MIB per CPU counters are allocated with GFP_KERNEL, which is not suitible for allocation inside an atomic context
+ * or spinlock. Instead of revising the infrastructure with an option to allocate the counters with GFP_ATOMIC,
+ * we add an option to allocate the counters lazily using delayed work.
+ */
+struct stat_hash_entry *
+stat_hash_get_entry(u32 initval, struct stat_hash_addr *addr,
+ bool existing, int alloc_flag, struct stat_hash_cookie *cookie);
+
+
+
+
+
+/* Used for printing the IP address for debugging purposes */
+void stat_hash_dump_address(struct stat_hash_addr *addr);
+
+extern int net_stat_hashtable;
+extern int net_stat_hash_loopback;
+extern int net_stat_ipv4_sysctl_hash_delete;
+extern int net_stat_ipv4_sysctl_hash_zero;
+extern int stat_hash_enable_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos);
+extern int stat_hash_ipv4_delete_hash_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos);
+extern int stat_hash_ipv4_zero_hash_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos);
+
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+extern int net_stat_hashtable_ipv6;
+extern int net_stat_ipv6_sysctl_hash_delete;
+extern int net_stat_ipv6_sysctl_hash_zero;
+extern int stat_hash_ipv6_delete_hash_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos);
+extern int stat_hash_ipv6_zero_hash_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos);
+#endif
+
+extern int stat_hash_sysctl_hash_max[STAT_HASH_INFO_MAX];
+
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLE_DEBUG
+enum {
+ STAT_HASH_MESSAGE_ERROR,
+ STAT_HASH_MESSAGE_WARNING,
+ STAT_HASH_MESSAGE_NOTICE,
+ STAT_HASH_MESSAGE_INFO,
+ STAT_HASH_MESSAGE_DEBUG,
+ STAT_HASH_MESSAGE_DEBUG_VERBOSE,
+};
+
+extern int stat_hash_debug_level;
+#endif
+
+#endif
+
+#endif
diff -r -U 4 a/kernel/sysctl_check.c b/kernel/sysctl_check.c
--- a/kernel/sysctl_check.c 2013-09-02 12:44:17.440680048 +0300
+++ b/kernel/sysctl_check.c 2013-09-02 12:44:17.586622176 +0300
@@ -541,8 +541,11 @@
{ NET_NF_CONNTRACK_FRAG6_TIMEOUT, "nf_conntrack_frag6_timeout" },
{ NET_NF_CONNTRACK_FRAG6_LOW_THRESH, "nf_conntrack_frag6_low_thresh" },
{ NET_NF_CONNTRACK_FRAG6_HIGH_THRESH, "nf_conntrack_frag6_high_thresh" },
{ NET_IPV6_MLD_MAX_MSF, "mld_max_msf" },
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+ { NET_CORE_STAT_HASHTABLE_IPV6, "stat_hash_ipv6" },
+#endif
{ 2088 /* IPQ_QMAX */, "ip6_queue_maxlen" },
{}
};
diff -r -U 4 a/net/ipv4/Kconfig b/net/ipv4/Kconfig
--- a/net/ipv4/Kconfig 2013-09-02 12:44:17.452622191 +0300
+++ b/net/ipv4/Kconfig 2013-09-02 12:44:17.612729975 +0300
@@ -650,4 +650,23 @@
the counters are allocated per CPU and each counter is 8 bytes.
This feature enables allocation of only a subset of counters from within a stat mib
by defining a mapping between the whole range of counters to a smaller set.
+config NET_IPV4_STAT_HASHTABLES
+ boolean "Define a hash table to hold per-ip IPV4 statistics"
+ depends on NET_IPV4_SNMP_MAPPING
+ default y
+ ---help---
+ Define a hash table to hold per-ip IPV4 statistics
+
+config NET_IPV4_STAT_HASHTABLE_SIZE
+ int "Define size of per-ip statistics hashtable"
+ depends on NET_IPV4_STAT_HASHTABLES
+ default "2048"
+
+config NET_IPV4_STAT_HASHTABLE_DEBUG
+ boolean "Debug statistics hash table functionality"
+ depends on NET_IPV4_STAT_HASHTABLES
+ default n
+ ---help---
+ Debug statistics hash table functionality
+
diff -r -U 4 a/net/ipv4/Makefile b/net/ipv4/Makefile
--- a/net/ipv4/Makefile 2013-09-02 12:44:17.459626370 +0300
+++ b/net/ipv4/Makefile 2013-09-02 12:44:17.636812490 +0300
@@ -52,5 +52,6 @@
obj-$(CONFIG_XFRM) += xfrm4_policy.o xfrm4_state.o xfrm4_input.o \
xfrm4_output.o
obj-$(CONFIG_NET_IPV4_SNMP_MAPPING) += snmp_map.o
+obj-$(CONFIG_NET_IPV4_STAT_HASHTABLES) += stat_hashtable.o
diff -r -U 4 a/net/ipv4/proc.c b/net/ipv4/proc.c
--- a/net/ipv4/proc.c 2013-09-02 12:44:17.467626639 +0300
+++ b/net/ipv4/proc.c 2013-09-02 12:44:17.651769979 +0300
@@ -44,8 +44,12 @@
#include <linux/seq_file.h>
#include <net/sock.h>
#include <net/raw.h>
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+#include <net/snmp_map.h>
+#endif
+
/*
* Report socket allocation statistics [mea@xxxxxx]
*/
static int sockstat_seq_show(struct seq_file *seq, void *v)
@@ -450,19 +454,43 @@
.llseek = seq_lseek,
.release = single_release_net,
};
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+extern int show_hash4_info(struct seq_file *, void *v);
+
+static int stat4_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, show_hash4_info, NULL);
+}
+
+static const struct file_operations stat4_hash_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = stat4_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+#endif
+
static __net_init int ip_proc_init_net(struct net *net)
{
if (!proc_net_fops_create(net, "sockstat", S_IRUGO, &sockstat_seq_fops))
goto out_sockstat;
if (!proc_net_fops_create(net, "netstat", S_IRUGO, &netstat_seq_fops))
goto out_netstat;
if (!proc_net_fops_create(net, "snmp", S_IRUGO, &snmp_seq_fops))
goto out_snmp;
-
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+ if (!proc_net_fops_create(net, "perip", S_IRUGO, &stat4_hash_seq_fops))
+ goto out_hash;
+#endif
return 0;
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+out_hash:
+ proc_net_remove(net, "snmp");
+#endif
out_snmp:
proc_net_remove(net, "netstat");
out_netstat:
proc_net_remove(net, "sockstat");
@@ -471,8 +499,11 @@
}
static __net_exit void ip_proc_exit_net(struct net *net)
{
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+ proc_net_remove(net, "perip");
+#endif
proc_net_remove(net, "snmp");
proc_net_remove(net, "netstat");
proc_net_remove(net, "sockstat");
}
@@ -483,7 +514,11 @@
};
int __init ip_misc_proc_init(void)
{
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+ snmp_map_register_labels(SNMP_TCP_MIB, snmp4_tcp_list, sizeof(snmp4_tcp_list) / sizeof(struct snmp_mib));
+ snmp_map_register_labels(SNMP_LINUX_MIB, snmp4_net_list, sizeof(snmp4_net_list) / sizeof(struct snmp_mib));
+#endif
return register_pernet_subsys(&ip_proc_ops);
}
diff -r -U 4 a/net/ipv4/stat_hashtable.c b/net/ipv4/stat_hashtable.c
--- a/net/ipv4/stat_hashtable.c 2013-09-02 12:44:17.474632471 +0300
+++ b/net/ipv4/stat_hashtable.c 2013-09-02 12:44:17.667792078 +0300
@@ -0,0 +1,876 @@
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/seq_file.h>
+#include <linux/ip.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/socket.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/jhash.h>
+#include <linux/bitmap.h>
+#include <linux/kthread.h>
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+#include <linux/in6.h>
+#include <linux/ipv6.h>
+#include <net/ipv6.h>
+#endif
+
+#include <net/stat_hashtable.h>
+
+int net_stat_hashtable = 1;
+EXPORT_SYMBOL(net_stat_hashtable);
+
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLE_DEBUG
+int stat_hash_debug_level = 0;
+EXPORT_SYMBOL(stat_hash_debug_level);
+#endif
+
+bool stat_hash_data_collection_started = false;
+EXPORT_SYMBOL(stat_hash_data_collection_started);
+
+int net_stat_hash_loopback = 0;
+int net_stat_ipv4_sysctl_hash_delete;
+int net_stat_ipv4_sysctl_hash_zero;
+
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+int net_stat_hashtable_ipv6 = 0;
+EXPORT_SYMBOL(net_stat_hashtable_ipv6);
+
+int net_stat_ipv6_sysctl_hash_delete;
+EXPORT_SYMBOL(net_stat_ipv6_sysctl_hash_delete);
+
+int net_stat_ipv6_sysctl_hash_zero;
+EXPORT_SYMBOL(net_stat_ipv6_sysctl_hash_zero);
+#endif
+
+#define STAT_HASH_MAX_DEFAULT 1024
+int stat_hash_sysctl_hash_max[STAT_HASH_INFO_MAX] = {
+ STAT_HASH_MAX_DEFAULT,
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ STAT_HASH_MAX_DEFAULT
+#endif
+};
+
+#define STAT_HASH_PREFIX "stat_hash: "
+
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLE_DEBUG
+#define stat_dprintk(level, format...) \
+ if ((stat_hash_debug_level) >= (level)) \
+ printk(KERN_DEBUG STAT_HASH_PREFIX format)
+#else
+#define stat_dprintk(level, format...)
+#endif
+
+#define atomic_set_mb(v,i) \
+ do { \
+ smp_mb(); \
+ atomic_set(v,i); \
+ smp_mb(); \
+ } while (0)
+
+typedef void (*stat_hash_copy_entry_addr_t)(struct stat_hash_entry *entry, struct stat_hash_addr *addr);
+typedef void (*stat_hash_print_t)(struct stat_hash_addr *addr);
+typedef void (*stat_hash_print_seq_t)(struct seq_file *seq, struct stat_hash_entry *entry);
+
+static void stat_hash_alloc_delayed(struct work_struct *);
+
+struct stat_hash_access_info {
+ spinlock_t lock;
+ atomic_t sequence;
+ atomic_t count;
+ int *max;
+ stat_hash_print_t print;
+ stat_hash_print_seq_t print_seq;
+ stat_hash_copy_entry_addr_t copy;
+ void *lock_bitmap;
+};
+
+static void stat4_copy_entry_addr(struct stat_hash_entry *entry, struct stat_hash_addr *addr);
+static void stat4_dump_address(struct stat_hash_addr *addr);
+static void stat4_dump_entry_address(struct seq_file *seq, struct stat_hash_entry *entry);
+
+#define STAT4_HASH_TABLE_SIZE CONFIG_NET_IPV4_STAT_HASHTABLE_SIZE
+static struct hlist_head stat4_hashtable[STAT4_HASH_TABLE_SIZE];
+static DECLARE_BITMAP(stat4_hashtable_lock_bitmap, STAT4_HASH_TABLE_SIZE);
+static struct stat_hash_access_info stat4_access_info = {
+ .lock = SPIN_LOCK_UNLOCKED,
+ .sequence = ATOMIC_INIT(0),
+ .count = ATOMIC_INIT(0),
+ .max = &stat_hash_sysctl_hash_max[STAT_HASH_IPV4_INFO],
+ .print = stat4_dump_address,
+ .print_seq = stat4_dump_entry_address,
+ .copy = stat4_copy_entry_addr,
+ .lock_bitmap = stat4_hashtable_lock_bitmap,
+};
+
+struct stat_hash_lookup_info stat4_lookup_info = {
+ .len = STAT4_HASH_TABLE_SIZE,
+ .first_sequence = 0,
+ .htable = stat4_hashtable,
+};
+
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+
+static void stat6_copy_entry_addr(struct stat_hash_entry *entry, struct stat_hash_addr *addr);
+static void stat6_dump_address(struct stat_hash_addr *addr);
+static void stat6_dump_entry_address(struct seq_file *seq, struct stat_hash_entry *entry);
+
+#define STAT6_HASH_TABLE_SIZE CONFIG_NET_IPV4_STAT_HASHTABLE_SIZE
+static struct hlist_head stat6_hashtable[STAT6_HASH_TABLE_SIZE];
+static DECLARE_BITMAP(stat6_hashtable_lock_bitmap, STAT6_HASH_TABLE_SIZE);
+static struct stat_hash_access_info stat6_access_info = {
+ .lock = SPIN_LOCK_UNLOCKED,
+ .sequence = ATOMIC_INIT(0),
+ .count = ATOMIC_INIT(0),
+ .max = &stat_hash_sysctl_hash_max[STAT_HASH_IPV6_INFO],
+ .print = stat6_dump_address,
+ .print_seq = stat6_dump_entry_address,
+ .copy = stat6_copy_entry_addr,
+ .lock_bitmap = stat6_hashtable_lock_bitmap,
+};
+
+struct stat_hash_lookup_info stat6_lookup_info = {
+ .len = STAT6_HASH_TABLE_SIZE,
+ .first_sequence = 0,
+ .htable = stat6_hashtable,
+};
+#endif
+
+static struct stat_hash_access_info *stat_access_info[] = {
+ &stat4_access_info,
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ &stat6_access_info,
+#endif
+};
+
+struct stat_hash_lookup_info *stat_lookup_info[STAT_HASH_INFO_MAX] = {
+ &stat4_lookup_info,
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ &stat6_lookup_info,
+#endif
+};
+EXPORT_SYMBOL(stat_lookup_info);
+
+static inline struct stat_hash_access_info *
+stat_hash_get_access_info(u16 family)
+{
+ struct stat_hash_access_info *info = NULL;
+
+ switch (family) {
+ case AF_INET:
+ info = stat_access_info[STAT_HASH_IPV4_INFO];
+ break;
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ case AF_INET6:
+ info = stat_access_info[STAT_HASH_IPV6_INFO];
+ break;
+#endif
+ default:
+ stat_dprintk(STAT_HASH_MESSAGE_NOTICE, "unsupported family %d\n", family);
+ break;
+ }
+
+ return info;
+}
+
+static inline int
+stat_hash_get_info(u16 family, struct stat_hash_access_info **access_info,
+ struct stat_hash_lookup_info **lookup_info)
+{
+ struct stat_hash_access_info *a = stat_hash_get_access_info(family);
+ struct stat_hash_lookup_info *l = stat_hash_get_lookup_info(family);
+
+ if (a == NULL || l == NULL)
+ return -EINVAL;
+
+ *access_info = a;
+ *lookup_info = l;
+
+ return 0;
+}
+
+static void stat_destroy(struct stat_hash_entry *entry);
+
+/*
+ * Helper functions shared by both ipv4 and ipv6
+ */
+static struct stat_hash_entry *
+__alloc_stat_entry(void)
+{
+ struct stat_hash_entry *entry = NULL;
+ int err, i;
+
+ entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
+ if (entry == NULL) {
+ printk(KERN_NOTICE STAT_HASH_PREFIX "OOM while allocating a new hash entry\n");
+ err = -ENOMEM;
+ goto out;
+ }
+
+ INIT_RCU_HEAD(&entry->rcu);
+
+ for (i = 0; i < SNMP_MAP_LEVEL_MAX; i++) {
+ entry->mappings[i].delayed = kzalloc(sizeof(struct state_hash_entry_delayed), GFP_ATOMIC);
+ if (entry->mappings[i].delayed == NULL) {
+ printk(KERN_NOTICE STAT_HASH_PREFIX "OOM while allocating delayed work section for a new hash entry\n");
+ err = -ENOMEM;
+ goto out_destroy;
+ }
+ entry->mappings[i].state.counter = STAT_HASH_MAPPING_STATE_ENTRY;
+ entry->mappings[i].delayed->mapping = &entry->mappings[i];
+ INIT_DELAYED_WORK(&entry->mappings[i].delayed->alloc_work, stat_hash_alloc_delayed);
+ }
+
+ return entry;
+
+out_destroy:
+ for (i = 0; i < SNMP_MAP_LEVEL_MAX; i++) {
+ if (entry->mappings[i].delayed != NULL)
+ kfree(entry->mappings[i].delayed);
+ }
+ kfree(entry);
+out:
+ return ERR_PTR(err);
+}
+
+static int
+stat_alloc_mibs(struct stat_hash_entry_mappings *mapping)
+{
+ int err, maplvl;
+ struct stat_hash_entry *entry;
+
+ maplvl = mapping->tcp_stats.maplvl;
+ entry = container_of(mapping, struct stat_hash_entry, mappings[maplvl]);
+
+ if ((err = snmp_map_mib_init((struct snmp_mib_map *) &mapping->tcp_stats)) < 0)
+ goto out_err;
+
+ if ((err = snmp_map_mib_init((struct snmp_mib_map *) &mapping->lnx_stats)) < 0)
+ goto out_free_tcp_mib;
+
+ stat_dprintk(STAT_HASH_MESSAGE_INFO, "mapping %d has been allocated for entry sequence %d\n",
+ maplvl, entry->sequence);
+
+ return 0;
+
+out_free_tcp_mib:
+ snmp_map_mib_free((struct snmp_mib_map *) &mapping->tcp_stats);
+out_err:
+
+ return err;
+}
+
+static void
+stat_free_mibs(struct stat_hash_entry *entry)
+{
+ int i;
+
+ for (i = SNMP_MAP_LEVEL_MAX - 1; i > 0; i--) {
+ smp_mb();
+ if (atomic_cmpxchg(&entry->mappings[i].state, STAT_HASH_MAPPING_STATE_ALLOCATED,
+ STAT_HASH_MAPPING_STATE_ENTRY) == STAT_HASH_MAPPING_STATE_ALLOCATED) {
+ smp_mb();
+ snmp_map_mib_free((struct snmp_mib_map *) &entry->mappings[i].tcp_stats);
+ snmp_map_mib_free((struct snmp_mib_map *) &entry->mappings[i].lnx_stats);
+ }
+ }
+}
+
+static int
+stat_hash_alloc_counters(struct stat_hash_entry_mappings *mapping)
+{
+ int err;
+
+ if ((err = stat_alloc_mibs(mapping)) < 0)
+ return err;
+
+ /* We don't need the delayed allocation stuff any more */
+ kfree(mapping->delayed);
+ mapping->delayed = NULL;
+
+ atomic_set_mb(&mapping->state, STAT_HASH_MAPPING_STATE_ALLOCATED);
+
+ return 0;
+}
+
+#define STAT_DELAYED_ALLOC_PERIOD ((2 * HZ)/3)
+static void
+stat_hash_alloc_delayed(struct work_struct *work)
+{
+ int err, maplvl;
+ struct stat_hash_entry *entry;
+ struct state_hash_entry_delayed *delayed = container_of(work, struct state_hash_entry_delayed, alloc_work.work);
+ struct stat_hash_entry_mappings *mapping = delayed->mapping;
+
+ maplvl = mapping->tcp_stats.maplvl;
+ entry = container_of(mapping, struct stat_hash_entry, mappings[maplvl]);
+
+ stat_dprintk(STAT_HASH_MESSAGE_INFO, "proccessing delayed allocation for entry sequence %d, mapping %d\n",
+ entry->sequence, maplvl);
+
+ if ((err = stat_hash_alloc_counters(mapping)) < 0) {
+ printk(KERN_NOTICE STAT_HASH_PREFIX "error %d while allocating mapping %d for entry sequence %d\n",
+ err, maplvl, entry->sequence);
+
+ atomic_set_mb(&mapping->state, STAT_HASH_MAPPING_STATE_ENTRY);
+ }
+}
+
+static int
+stat_hash_alloc_mappings(struct stat_hash_entry *entry, int alloc_flag)
+{
+ int err = 0, i, map_level = snmp_map_level, again = 0;
+ struct stat_hash_entry_mappings *mapping;
+
+ for (i = 0; i <= map_level; i++) {
+ mapping = &entry->mappings[i];
+ smp_mb();
+ if (atomic_cmpxchg(&mapping->state, STAT_HASH_MAPPING_STATE_ENTRY,
+ STAT_HASH_MAPPING_STATE_ALLOCATING) == STAT_HASH_MAPPING_STATE_ENTRY) {
+ smp_mb();
+ if (alloc_flag == STAT_HASH_ALLOC_FLAG_ALLOC) {
+ if ((err = stat_hash_alloc_counters(mapping)) < 0)
+ goto out_rollback;
+ } else {
+ stat_dprintk(STAT_HASH_MESSAGE_INFO, "scheduled delayed allocation for entry sequence %d, mapping %d\n",
+ entry->sequence, i);
+
+ schedule_delayed_work(&mapping->delayed->alloc_work, STAT_DELAYED_ALLOC_PERIOD);
+ }
+ } else {
+ again = 1;
+ continue;
+ }
+ }
+
+ return ((again) ? -EAGAIN : err);
+
+out_rollback:
+ atomic_set_mb(&mapping->state, STAT_HASH_MAPPING_STATE_ENTRY);
+
+ printk(KERN_NOTICE STAT_HASH_PREFIX "error %d while allocating mapping %d for entry sequence %d\n",
+ err, i, entry->sequence);
+
+ return err;
+}
+
+static int
+stat_hash_init_mappings(struct stat_hash_entry *entry)
+{
+ int err = 0, i;
+ struct stat_hash_entry_mappings *mapping;
+
+ for (i = 0; i < SNMP_MAP_LEVEL_MAX; i++) {
+ mapping = &entry->mappings[i];
+ if ((err = snmp_map_init_map(i, SNMP_TCP_MIB, (struct snmp_mib_map *) &mapping->tcp_stats)) < 0)
+ break;
+
+ if ((err = snmp_map_init_map(i, SNMP_LINUX_MIB, (struct snmp_mib_map *) &mapping->lnx_stats)) < 0)
+ break;
+ }
+
+ if (err != 0)
+ printk(KERN_NOTICE STAT_HASH_PREFIX "error %d while initializing mapping %d for new entry\n",
+ err, i);
+
+ return err;
+}
+
+static struct stat_hash_cookie *
+stat_fill_cookie(struct stat_hash_entry *entry, u16 family, u16 bucket, struct stat_hash_cookie *cookie)
+{
+ if (cookie != NULL) {
+ cookie->hash.family = family;
+ cookie->hash.bucket = bucket;
+ atomic_set_mb(&cookie->seq, entry->sequence);
+ }
+
+ return cookie;
+}
+
+/*
+ * IPV4 stat hashtable
+ */
+static void
+stat4_copy_entry_addr(struct stat_hash_entry *entry, struct stat_hash_addr *addr)
+{
+ entry->addr.family = addr->family;
+ entry->addr.saddr.ip = addr->saddr.ip;
+ entry->addr.daddr.ip = addr->daddr.ip;
+}
+
+static void
+stat4_dump_address(struct stat_hash_addr *addr)
+{
+ printk(KERN_NOTICE STAT_HASH_PREFIX "IPV4 address pair: %pI4, %pI4\n", &addr->saddr, &addr->daddr);
+}
+
+static void
+stat4_dump_entry_address(struct seq_file *seq, struct stat_hash_entry *entry)
+{
+ seq_printf(seq, "%pI4, %pI4", &entry->addr.saddr, &entry->addr.daddr);
+}
+
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+static void
+stat6_copy_entry_addr(struct stat_hash_entry *entry, struct stat_hash_addr *addr)
+{
+ entry->addr.family = addr->family;
+ ipv6_addr_copy(&entry->addr.saddr.in6, &addr->saddr.in6);
+ ipv6_addr_copy(&entry->addr.daddr.in6, &addr->daddr.in6);
+}
+
+static void
+stat6_dump_address(struct stat_hash_addr *addr)
+{
+ printk(KERN_NOTICE STAT_HASH_PREFIX "IPV6 addresss pair: %pI6, %pI6\n", &addr->saddr.in6, &addr->daddr.in6);
+}
+
+static void
+stat6_dump_entry_address(struct seq_file *seq, struct stat_hash_entry *entry)
+{
+ seq_printf(seq, "%pI6, %pI6", &entry->addr.saddr.in6, &entry->addr.daddr.in6);
+}
+#endif
+
+static struct stat_hash_entry *
+stat_hash_alloc_entry(u32 initval, struct stat_hash_addr *addr)
+{
+ struct stat_hash_entry *entry = NULL;
+ struct stat_hash_access_info *access_info;
+ struct stat_hash_lookup_info *lookup_info;
+
+ if (stat_hash_get_info(addr->family, &access_info, &lookup_info) < 0)
+ return NULL;
+
+ entry = __alloc_stat_entry();
+ if (entry && !IS_ERR(entry)) {
+ entry->sequence = atomic_inc_return(&access_info->sequence);
+ access_info->copy(entry, addr);
+ }
+
+ return entry;
+}
+
+static bool
+stat_hash_all_processed_allocate(struct stat_hash_entry *entry)
+{
+ int i, map_level = snmp_map_level;
+
+ for (i = 0; i < map_level; i++) {
+ if (!stat_hash_mapping_state(entry, i, STAT_HASH_MAPPING_STATE_ALLOCATING) ||
+ !stat_hash_mapping_state(entry, i, STAT_HASH_MAPPING_STATE_ALLOCATED))
+ return false;
+ }
+
+ return true;
+}
+
+struct stat_hash_entry *
+stat_hash_get_entry(u32 initval, struct stat_hash_addr *addr,
+ bool existing, int alloc_flag, struct stat_hash_cookie *cookie)
+{
+ struct stat_hash_access_info *access_info = NULL;
+ struct stat_hash_lookup_info *lookup_info = NULL;
+ struct stat_hash_entry *entry = NULL;
+ u16 bucket = 0;
+ int err;
+
+ if (stat_hash_get_info(addr->family, &access_info, &lookup_info) < 0)
+ return NULL;
+
+ /* Fail here if we are looking for an existing entry and it does not exists */
+ entry = stat_hash_lookup_addr(initval, addr, &bucket);
+
+
+ if (existing && (entry == NULL)) {
+ stat_dprintk(STAT_HASH_MESSAGE_DEBUG, "hash entry does not exist - unable to reuse\n");
+ return NULL;
+ }
+
+ /*
+ * If we find an entry reuse it, possibly allocating additional map levels.
+ */
+ if (entry != NULL) {
+ stat_fill_cookie(entry, addr->family, bucket, cookie);
+ stat_dprintk(STAT_HASH_MESSAGE_DEBUG, "reusining entry (family = %d, bucket = %d, sequence = %d)\n",
+ cookie->hash.family, cookie->hash.bucket, entry->sequence);
+
+ if (!stat_hash_all_processed_allocate(entry)) {
+ if ((err = stat_hash_alloc_mappings(entry, alloc_flag)) < 0) {
+ if (err == -EAGAIN) {
+ stat_dprintk(STAT_HASH_MESSAGE_DEBUG, "mapping not in correct state for alloc (family = %d, bucket = %d, sequence = %d)\n",
+ cookie->hash.family, cookie->hash.bucket, entry->sequence);
+ } else {
+ stat_dprintk(STAT_HASH_MESSAGE_NOTICE, "error %d while allocating mapping (family = %d, bucket = %d, sequence = %d)\n",
+ err, cookie->hash.family, cookie->hash.bucket, entry->sequence);
+ }
+ }
+ }
+
+ return entry;
+ }
+
+ /* we cannot allocate a new entry - bail out */
+ if (alloc_flag == STAT_HASH_ALLOC_FLAG_NOALLOC) {
+ stat_dprintk(STAT_HASH_MESSAGE_INFO, "cannot allocate a new entry at this stage\n");
+ return NULL;
+ }
+
+ if (atomic_read(&access_info->count) >= *(access_info->max)) {
+ stat_dprintk(STAT_HASH_MESSAGE_NOTICE, "insert failed - reached maximum entry count\n");
+ return NULL;
+ }
+
+ bucket = stat_hash_bucket(lookup_info->len, initval, addr);
+ if (test_and_set_bit(bucket, access_info->lock_bitmap)) {
+ stat_dprintk(STAT_HASH_MESSAGE_INFO, "insert failed - bucket lock held\n");
+ return NULL;
+ }
+
+ /* Allocate a new entry for the supplied address. */
+ entry = stat_hash_alloc_entry(initval, addr);
+ if (IS_ERR(entry))
+ goto err_unlock;
+ else {
+ if ((err = stat_hash_init_mappings(entry)) < 0)
+ goto err_destroy;
+
+ if ((err = stat_hash_alloc_mappings(entry, alloc_flag)) < 0)
+ goto err_destroy;
+
+ stat_fill_cookie(entry, addr->family, bucket, cookie);
+ stat_dprintk(STAT_HASH_MESSAGE_NOTICE, "new entry added (family = %d, bucket = %d, sequence = %d)\n",
+ cookie->hash.family, cookie->hash.bucket, entry->sequence);
+
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLE_DEBUG
+ if (stat_hash_debug_level >= STAT_HASH_MESSAGE_NOTICE)
+ access_info->print(addr);
+#endif
+ spin_lock(&access_info->lock);
+ hlist_add_head_rcu(&entry->hlist, &lookup_info->htable[bucket]);
+ atomic_inc(&access_info->count);
+ spin_unlock(&access_info->lock);
+ clear_bit(bucket, access_info->lock_bitmap);
+ smp_mb();
+
+ }
+
+ return entry;
+
+err_destroy:
+ kfree(entry);
+err_unlock:
+ clear_bit(bucket, access_info->lock_bitmap);
+ smp_mb();
+
+ return NULL;
+}
+
+void
+stat_hash_dump_address(struct stat_hash_addr *addr)
+{
+ struct stat_hash_access_info *info;
+
+ info = stat_hash_get_access_info(addr->family);
+ if (info == NULL)
+ return;
+
+ info->print(addr);
+}
+
+static void
+stat_destroy_rcu(struct rcu_head *head)
+{
+ struct stat_hash_entry *entry = container_of(head, struct stat_hash_entry, rcu);
+ stat_free_mibs(entry);
+ kfree(entry);
+}
+
+static void
+stat_destroy(struct stat_hash_entry *entry)
+{
+ hlist_del_rcu(&entry->hlist);
+ call_rcu(&entry->rcu, stat_destroy_rcu);
+}
+
+static void
+stat_zero(struct stat_hash_entry *entry, int maplvl)
+{
+ if (stat_hash_mapping_allocated(entry, maplvl)) {
+ snmp_map_mib_zero((struct snmp_mib_map *) &entry->mappings[maplvl].tcp_stats);
+ snmp_map_mib_zero((struct snmp_mib_map *) &entry->mappings[maplvl].lnx_stats);
+ }
+}
+
+static void
+stat_hash_dump_stats(struct seq_file *seq, struct stat_hash_entry *entry)
+{
+ int i, initialized = 0, map_level = snmp_map_level;
+ union snmp_mib_map_bitmaps test_negative;
+
+ if (!stat_hash_any_allocated(entry))
+ return;
+
+ /* Setup counters to be tested for negative value and possibly zeroed prior to display */
+ memset(&test_negative, 0, sizeof(union snmp_mib_map_bitmaps));
+ set_bit(TCP_MIB_CURRESTAB, test_negative.bmap.bitmap);
+
+ for (i = 0; i <= map_level; i++) {
+ if (stat_hash_mapping_allocated(entry, i)) {
+ if (snmp_map_count((struct snmp_mib_map *) &entry->mappings[i].tcp_stats) > 0) {
+ if (0 == initialized++)
+ seq_printf(seq, "Tcp:\n");
+ snmp_map_print_stats(seq, (struct snmp_mib_map *) &entry->mappings[i].tcp_stats, &test_negative);
+ }
+ }
+ }
+ if (initialized > 0)
+ seq_putc(seq, '\n');
+
+ initialized = 0;
+ for (i = 0; i <= map_level; i++) {
+ if (stat_hash_mapping_allocated(entry, i)) {
+ if (snmp_map_count((struct snmp_mib_map *) &entry->mappings[i].lnx_stats) > 0) {
+ if (0 == initialized++)
+ seq_printf(seq, "TcpExt:\n");
+ snmp_map_print_stats(seq, (struct snmp_mib_map *) &entry->mappings[i].lnx_stats, NULL);
+ }
+ }
+ }
+ if (initialized > 0)
+ seq_putc(seq, '\n');
+}
+
+static void
+stat_hash_show_entry(u16 family, struct seq_file *seq, struct stat_hash_entry *entry)
+{
+ struct stat_hash_access_info *info;
+
+ info = stat_hash_get_access_info(family);
+ if (info == NULL)
+ return;
+
+ info->print_seq(seq, entry);
+ seq_printf(seq, ":\n");
+ stat_hash_dump_stats(seq, entry);
+ seq_putc(seq, '\n');
+}
+
+static void
+stat_hash_delete_all(u16 family)
+{
+ struct stat_hash_access_info *access_info;
+ struct stat_hash_lookup_info *lookup_info;
+ struct hlist_head *htable;
+ struct hlist_head *head;
+ struct hlist_node *pos, *n;
+ struct stat_hash_entry *entry;
+ int i;
+
+ if (stat_hash_get_info(family, &access_info, &lookup_info) < 0)
+ return;
+
+ htable = lookup_info->htable;
+
+ spin_lock(&access_info->lock);
+ for (i = 0; i < lookup_info->len; i++) {
+ head = &htable[i];
+ hlist_for_each_entry_safe(entry, pos, n, head, hlist)
+ stat_destroy(entry);
+ }
+ lookup_info->first_sequence = atomic_read(&access_info->sequence);
+ atomic_set_mb(&access_info->count, 0);
+ spin_unlock(&access_info->lock);
+}
+
+static void
+stat_hash_zero_mapping(u16 family, int maplvl)
+{
+ struct stat_hash_access_info *access_info;
+ struct stat_hash_lookup_info *lookup_info;
+ struct hlist_head *htable;
+ struct hlist_head *head;
+ struct hlist_node *pos;
+ struct stat_hash_entry *entry;
+ int i;
+
+ if (stat_hash_get_info(family, &access_info, &lookup_info) < 0)
+ return;
+
+ htable = lookup_info->htable;
+
+ spin_lock(&access_info->lock);
+ for (i = 0; i < lookup_info->len; i++) {
+ head = &htable[i];
+ hlist_for_each_entry(entry, pos, head, hlist)
+ stat_zero(entry, maplvl);
+ }
+ spin_unlock(&access_info->lock);
+}
+
+static void
+stat_hash_iter(u16 family, struct seq_file *seq)
+{
+ struct stat_hash_lookup_info *lookup_info = NULL;
+ struct stat_hash_entry *entry;
+ struct hlist_head *head;
+ struct hlist_node *pos;
+ struct hlist_head *htable;
+ int i;
+
+ lookup_info = stat_hash_get_lookup_info(family);
+ if (lookup_info == NULL)
+ return;
+
+ htable = lookup_info->htable;
+
+ for (i = 0; i < lookup_info->len; i++) {
+ head = &htable[i];
+ hlist_for_each_entry_rcu(entry, pos, head, hlist) {
+ stat_hash_show_entry(family, seq, entry);
+ }
+ }
+}
+
+int
+show_hash4_info(struct seq_file *seq, void *v)
+{
+ stat_hash_iter(AF_INET, seq);
+ return 0;
+}
+
+int
+show_hash6_info(struct seq_file *seq, void *v)
+{
+ stat_hash_iter(AF_INET6, seq);
+ return 0;
+}
+EXPORT_SYMBOL(show_hash6_info);
+
+static int
+stat_hash_delete_hash_handler(u16 family, int *var, ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos)
+{
+ int err = 0;
+
+ if (!write)
+ err = -EINVAL;
+ else {
+ err = proc_dointvec_minmax(table, write, buffer, length, ppos);
+ if (err == 0) {
+ if (*var <= 0) {
+ printk(KERN_WARNING "invalid argument (valid argument > 0)\n");
+ err = -EINVAL;
+ } else
+ stat_hash_delete_all(family);
+ }
+ }
+
+ return err;
+}
+
+int
+stat_hash_ipv4_delete_hash_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos)
+{
+ return stat_hash_delete_hash_handler(AF_INET, &net_stat_ipv4_sysctl_hash_delete, table, write, buffer, length, ppos);
+}
+
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+int
+stat_hash_ipv6_delete_hash_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos)
+{
+ return stat_hash_delete_hash_handler(AF_INET6, &net_stat_ipv6_sysctl_hash_delete, table, write, buffer, length, ppos);
+}
+EXPORT_SYMBOL(stat_hash_ipv6_delete_hash_handler);
+#endif
+
+static int
+stat_hash_zero_hash_handler(u16 family, int *var, ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos)
+{
+ int err = 0;
+
+ if (!write)
+ err = -EINVAL;
+ else {
+ err = proc_dointvec_minmax(table, write, buffer, length, ppos);
+ if (err == 0) {
+ if (*var < 0 || *var >= SNMP_MAP_LEVEL_MAX) {
+ printk(KERN_WARNING "invalid map level (valid argument: %d - %d)\n", 0, SNMP_MAP_LEVEL_MAX - 1);
+ err = -EINVAL;
+ } else
+ stat_hash_zero_mapping(family, *var);
+ }
+ }
+
+ return err;
+}
+
+int
+stat_hash_ipv4_zero_hash_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos)
+{
+ return stat_hash_zero_hash_handler(AF_INET, &net_stat_ipv4_sysctl_hash_zero, table, write, buffer, length, ppos);
+}
+
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+int
+stat_hash_ipv6_zero_hash_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos)
+{
+ return stat_hash_zero_hash_handler(AF_INET6, &net_stat_ipv6_sysctl_hash_zero, table, write, buffer, length, ppos);
+}
+EXPORT_SYMBOL(stat_hash_ipv6_zero_hash_handler);
+#endif
+
+int
+stat_hash_enable_handler(ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos)
+{
+ int err = proc_dointvec_minmax(table, write, buffer, length, ppos);
+ if ((err == 0) && write)
+ smp_mb();
+
+ return err;
+}
+
+int
+stat_hash_start_data_collection(void)
+{
+ int err = 0;
+
+ if (stat_hash_data_collection_started) {
+ printk(KERN_NOTICE STAT_HASH_PREFIX "data collection already started\n");
+ return 0;
+ }
+
+ stat_hash_data_collection_started = true;
+ smp_mb();
+
+ return err;
+}
+EXPORT_SYMBOL(stat_hash_start_data_collection);
+
+void
+stat_hash_stop_data_collection(void)
+{
+ if (!stat_hash_data_collection_started) {
+ printk(KERN_NOTICE STAT_HASH_PREFIX "data collection was not started\n");
+ return;
+ }
+
+ stat_hash_data_collection_started = false;
+ smp_mb();
+}
+EXPORT_SYMBOL(stat_hash_stop_data_collection);
+
+static __init int
+stat_hash_init(void)
+{
+ memset(stat4_hashtable_lock_bitmap, 0, sizeof(stat4_hashtable_lock_bitmap));
+ memset(stat6_hashtable_lock_bitmap, 0, sizeof(stat6_hashtable_lock_bitmap));
+ return 0;
+}
+
+__initcall(stat_hash_init);
+
diff -r -U 4 a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
--- a/net/ipv4/sysctl_net_ipv4.c 2013-09-02 12:44:17.481628441 +0300
+++ b/net/ipv4/sysctl_net_ipv4.c 2013-09-02 12:44:17.687767866 +0300
@@ -825,8 +825,64 @@
.proc_handler = snmp_map_level_handler,
.strategy = &sysctl_intvec,
},
#endif
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+ {
+ .ctl_name = NET_IPV4_STAT_HASHTABLE_ENABLE,
+ .procname = "perip_stats",
+ .data = &net_stat_hashtable,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = stat_hash_enable_handler,
+ .strategy = &sysctl_intvec,
+ },
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLE_DEBUG
+ {
+ .ctl_name = NET_IPV4_STAT_HASHTABLE_DEBUG_LEVEL,
+ .procname = "perip_stats_debug",
+ .data = &stat_hash_debug_level,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec
+ },
+#endif
+ {
+ .ctl_name = NET_IPV4_STAT_HASHTABLE_LOOPBACK,
+ .procname = "perip_stats_loopback",
+ .data = &net_stat_hash_loopback,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec
+ },
+ {
+ .ctl_name = NET_IPV4_STAT_HASHTABLE_DELETE,
+ .procname = "perip_stats_delete_entries",
+ .data = &net_stat_ipv4_sysctl_hash_delete,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = stat_hash_ipv4_delete_hash_handler,
+ .strategy = &sysctl_intvec,
+ },
+ {
+ .ctl_name = NET_IPV4_STAT_HASHTABLE_ZERO,
+ .procname = "perip_stats_zero_counters",
+ .data = &net_stat_ipv4_sysctl_hash_zero,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = stat_hash_ipv4_zero_hash_handler,
+ .strategy = &sysctl_intvec,
+ },
+ {
+ .ctl_name = NET_IPV4_STAT_HASHTABLE_MAX,
+ .procname = "perip_stats_max_entries",
+ .data = &stat_hash_sysctl_hash_max,
+ .maxlen = sizeof(stat_hash_sysctl_hash_max),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .strategy = &sysctl_intvec,
+ },
+#endif
{ .ctl_name = 0 }
};
static struct ctl_table ipv4_net_table[] = {
diff -r -U 4 a/net/ipv6/Kconfig b/net/ipv6/Kconfig
--- a/net/ipv6/Kconfig 2013-09-02 12:44:17.491622411 +0300
+++ b/net/ipv6/Kconfig 2013-09-02 12:44:17.708919635 +0300
@@ -216,5 +216,12 @@
---help---
Support for IPv6 PIM multicast routing protocol PIM-SMv2.
If unsure, say N.
+config IPV6_STAT_HASHTABLES
+ boolean "Define a hash table to hold per-ip IPV6 statistics"
+ depends on IPV6 && NET_IPV4_STAT_HASHTABLES
+ default y
+ ---help---
+ Define a hash table to hold per-ip IPV6 statistics
+
endif # IPV6
diff -r -U 4 a/net/ipv6/proc.c b/net/ipv6/proc.c
--- a/net/ipv6/proc.c 2013-09-02 12:44:17.498640683 +0300
+++ b/net/ipv6/proc.c 2013-09-02 12:44:17.724867731 +0300
@@ -231,8 +231,25 @@
.llseek = seq_lseek,
.release = single_release,
};
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+extern int show_hash6_info(struct seq_file *, void *v);
+
+static int stat6_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, show_hash6_info, NULL);
+}
+
+static const struct file_operations stat6_hash_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = stat6_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+#endif
+
int snmp6_register_dev(struct inet6_dev *idev)
{
struct proc_dir_entry *p;
struct net *net;
@@ -278,10 +295,20 @@
net->mib.proc_net_devsnmp6 = proc_mkdir("dev_snmp6", net->proc_net);
if (!net->mib.proc_net_devsnmp6)
goto proc_dev_snmp6_fail;
+
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+ if (!proc_net_fops_create(net, "perip6", S_IRUGO, &stat6_hash_seq_fops))
+ goto proc_hash6_fail;
+#endif
+
return 0;
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+proc_hash6_fail:
+ proc_net_remove(net, "dev_snmp6");
+#endif
proc_snmp6_fail:
proc_net_remove(net, "sockstat6");
proc_dev_snmp6_fail:
proc_net_remove(net, "dev_snmp6");
@@ -292,8 +319,11 @@
{
proc_net_remove(net, "sockstat6");
proc_net_remove(net, "dev_snmp6");
proc_net_remove(net, "snmp6");
+#ifdef CONFIG_NET_IPV4_STAT_HASHTABLES
+ proc_net_remove(net, "perip6");
+#endif
}
static struct pernet_operations ipv6_proc_ops = {
.init = ipv6_proc_init_net,
diff -r -U 4 a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
--- a/net/ipv6/reassembly.c 2013-09-02 12:44:17.505628399 +0300
+++ b/net/ipv6/reassembly.c 2013-09-02 12:44:17.741702887 +0300
@@ -53,8 +53,12 @@
#include <net/ndisc.h>
#include <net/addrconf.h>
#include <net/inet_frag.h>
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+#include <net/ip.h>
+#endif
+
struct ip6frag_skb_cb
{
struct inet6_skb_parm h;
int offset;
@@ -589,8 +593,36 @@
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
.strategy = sysctl_jiffies,
},
+#ifdef CONFIG_IPV6_STAT_HASHTABLES
+ {
+ .ctl_name = NET_IPV6_STAT_HASHTABLE_ENABLE,
+ .procname = "perip_stats_ipv6",
+ .data = &net_stat_hashtable_ipv6,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec
+ },
+ {
+ .ctl_name = NET_IPV6_STAT_HASHTABLE_DELETE,
+ .procname = "perip_stats_delete_entries",
+ .data = &net_stat_ipv6_sysctl_hash_delete,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = stat_hash_ipv6_delete_hash_handler,
+ .strategy = &sysctl_intvec,
+ },
+ {
+ .ctl_name = NET_IPV6_STAT_HASHTABLE_ZERO,
+ .procname = "perip_stats_zero_counters",
+ .data = &net_stat_ipv6_sysctl_hash_zero,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = stat_hash_ipv6_zero_hash_handler,
+ .strategy = &sysctl_intvec,
+ },
+#endif
{ }
};
static struct ctl_table ip6_frags_ctl_table[] = {
--
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