/*
- * Copyright (c) 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
+ * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2015 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include <config.h>
#include "classifier.h"
+#include "classifier-private.h"
#include <errno.h>
#include <netinet/in.h>
#include "byte-order.h"
#include "dynamic-string.h"
-#include "flow.h"
-#include "hash.h"
-#include "hindex.h"
-#include "hmap.h"
-#include "list.h"
#include "odp-util.h"
#include "ofp-util.h"
-#include "ovs-thread.h"
#include "packets.h"
-#include "pvector.h"
-#include "tag.h"
#include "util.h"
-#include "vlog.h"
+#include "openvswitch/vlog.h"
VLOG_DEFINE_THIS_MODULE(classifier);
-struct trie_node;
struct trie_ctx;
+/* A collection of "struct cls_conjunction"s currently embedded into a
+ * cls_match. */
+struct cls_conjunction_set {
+ /* Link back to the cls_match.
+ *
+ * cls_conjunction_set is mostly used during classifier lookup, and, in
+ * turn, during classifier lookup the most used member of
+ * cls_conjunction_set is the rule's priority, so we cache it here for fast
+ * access. */
+ struct cls_match *match;
+ int priority; /* Cached copy of match->priority. */
+
+ /* Conjunction information.
+ *
+ * 'min_n_clauses' allows some optimization during classifier lookup. */
+ unsigned int n; /* Number of elements in 'conj'. */
+ unsigned int min_n_clauses; /* Smallest 'n' among elements of 'conj'. */
+ struct cls_conjunction conj[];
+};
+
/* Ports trie depends on both ports sharing the same ovs_be32. */
#define TP_PORTS_OFS32 (offsetof(struct flow, tp_src) / 4)
BUILD_ASSERT_DECL(TP_PORTS_OFS32 == offsetof(struct flow, tp_dst) / 4);
+BUILD_ASSERT_DECL(TP_PORTS_OFS32 % 2 == 0);
+#define TP_PORTS_OFS64 (TP_PORTS_OFS32 / 2)
-/* Prefix trie for a 'field' */
-struct cls_trie {
- const struct mf_field *field; /* Trie field, or NULL. */
- struct trie_node *root; /* NULL if none. */
-};
-
-enum {
- CLS_MAX_INDICES = 3 /* Maximum number of lookup indices per subtable. */
-};
-
-struct cls_classifier {
- int n_rules; /* Total number of rules. */
- uint8_t n_flow_segments;
- uint8_t flow_segments[CLS_MAX_INDICES]; /* Flow segment boundaries to use
- * for staged lookup. */
- struct hmap subtables_map; /* Contains "struct cls_subtable"s. */
- struct pvector subtables;
- struct hmap partitions; /* Contains "struct cls_partition"s. */
- struct cls_trie tries[CLS_MAX_TRIES]; /* Prefix tries. */
- unsigned int n_tries;
-};
-
-/* A set of rules that all have the same fields wildcarded. */
-struct cls_subtable {
- struct hmap_node hmap_node; /* Within struct cls_classifier 'subtables_map'
- * hmap. */
- struct hmap rules; /* Contains "struct cls_rule"s. */
- int n_rules; /* Number of rules, including duplicates. */
- unsigned int max_priority; /* Max priority of any rule in the subtable. */
- unsigned int max_count; /* Count of max_priority rules. */
- tag_type tag; /* Tag generated from mask for partitioning. */
- uint8_t n_indices; /* How many indices to use. */
- uint8_t index_ofs[CLS_MAX_INDICES]; /* u32 flow segment boundaries. */
- struct hindex indices[CLS_MAX_INDICES]; /* Staged lookup indices. */
- unsigned int trie_plen[CLS_MAX_TRIES]; /* Trie prefix length in 'mask'. */
- int ports_mask_len;
- struct trie_node *ports_trie; /* NULL if none. */
- struct minimask mask; /* Wildcards for fields. */
- /* 'mask' must be the last field. */
-};
+static size_t
+cls_conjunction_set_size(size_t n)
+{
+ return (sizeof(struct cls_conjunction_set)
+ + n * sizeof(struct cls_conjunction));
+}
-/* Associates a metadata value (that is, a value of the OpenFlow 1.1+ metadata
- * field) with tags for the "cls_subtable"s that contain rules that match that
- * metadata value. */
-struct cls_partition {
- struct hmap_node hmap_node; /* In struct cls_classifier's 'partitions'
- * hmap. */
- ovs_be64 metadata; /* metadata value for this partition. */
- tag_type tags; /* OR of each flow's cls_subtable tag. */
- struct tag_tracker tracker; /* Tracks the bits in 'tags'. */
-};
+static struct cls_conjunction_set *
+cls_conjunction_set_alloc(struct cls_match *match,
+ const struct cls_conjunction conj[], size_t n)
+{
+ if (n) {
+ size_t min_n_clauses = conj[0].n_clauses;
+ for (size_t i = 1; i < n; i++) {
+ min_n_clauses = MIN(min_n_clauses, conj[i].n_clauses);
+ }
-/* Internal representation of a rule in a "struct cls_subtable". */
-struct cls_match {
- struct cls_rule *cls_rule;
- struct hindex_node index_nodes[CLS_MAX_INDICES]; /* Within subtable's
- * 'indices'. */
- struct hmap_node hmap_node; /* Within struct cls_subtable 'rules'. */
- unsigned int priority; /* Larger numbers are higher priorities. */
- struct cls_partition *partition;
- struct list list; /* List of identical, lower-priority rules. */
- struct miniflow flow; /* Matching rule. Mask is in the subtable. */
- /* 'flow' must be the last field. */
-};
+ struct cls_conjunction_set *set = xmalloc(cls_conjunction_set_size(n));
+ set->match = match;
+ set->priority = match->priority;
+ set->n = n;
+ set->min_n_clauses = min_n_clauses;
+ memcpy(set->conj, conj, n * sizeof *conj);
+ return set;
+ } else {
+ return NULL;
+ }
+}
static struct cls_match *
-cls_match_alloc(struct cls_rule *rule)
+cls_match_alloc(const struct cls_rule *rule, cls_version_t version,
+ const struct cls_conjunction conj[], size_t n)
{
- int count = count_1bits(rule->match.flow.map);
+ size_t count = miniflow_n_values(rule->match.flow);
struct cls_match *cls_match
- = xmalloc(sizeof *cls_match - sizeof cls_match->flow.inline_values
- + MINIFLOW_VALUES_SIZE(count));
-
- cls_match->cls_rule = rule;
- miniflow_clone_inline(&cls_match->flow, &rule->match.flow, count);
- cls_match->priority = rule->priority;
- rule->cls_match = cls_match;
+ = xmalloc(sizeof *cls_match + MINIFLOW_VALUES_SIZE(count));
+
+ ovsrcu_init(&cls_match->next, NULL);
+ *CONST_CAST(const struct cls_rule **, &cls_match->cls_rule) = rule;
+ *CONST_CAST(int *, &cls_match->priority) = rule->priority;
+ *CONST_CAST(cls_version_t *, &cls_match->add_version) = version;
+ atomic_init(&cls_match->remove_version, version); /* Initially
+ * invisible. */
+ miniflow_clone(CONST_CAST(struct miniflow *, &cls_match->flow),
+ rule->match.flow, count);
+ ovsrcu_set_hidden(&cls_match->conj_set,
+ cls_conjunction_set_alloc(cls_match, conj, n));
return cls_match;
}
-static struct cls_subtable *find_subtable(const struct cls_classifier *,
+static struct cls_subtable *find_subtable(const struct classifier *cls,
const struct minimask *);
-static struct cls_subtable *insert_subtable(struct cls_classifier *,
+static struct cls_subtable *insert_subtable(struct classifier *cls,
const struct minimask *);
-
-static void destroy_subtable(struct cls_classifier *, struct cls_subtable *);
-
-static struct cls_match *find_match_wc(const struct cls_subtable *,
- const struct flow *, struct trie_ctx *,
- unsigned int n_tries,
- struct flow_wildcards *);
-static struct cls_match *find_equal(struct cls_subtable *,
+static void destroy_subtable(struct classifier *cls, struct cls_subtable *);
+
+static const struct cls_match *find_match_wc(const struct cls_subtable *,
+ cls_version_t version,
+ const struct flow *,
+ struct trie_ctx *,
+ unsigned int n_tries,
+ struct flow_wildcards *);
+static struct cls_match *find_equal(const struct cls_subtable *,
const struct miniflow *, uint32_t hash);
-static struct cls_match *insert_rule(struct cls_classifier *,
- struct cls_subtable *, struct cls_rule *);
-/* Iterates RULE over HEAD and all of the cls_rules on HEAD->list. */
-#define FOR_EACH_RULE_IN_LIST(RULE, HEAD) \
- for ((RULE) = (HEAD); (RULE) != NULL; (RULE) = next_rule_in_list(RULE))
-#define FOR_EACH_RULE_IN_LIST_SAFE(RULE, NEXT, HEAD) \
- for ((RULE) = (HEAD); \
- (RULE) != NULL && ((NEXT) = next_rule_in_list(RULE), true); \
- (RULE) = (NEXT))
+/* Return the next visible (lower-priority) rule in the list. Multiple
+ * identical rules with the same priority may exist transitionally, but when
+ * versioning is used at most one of them is ever visible for lookups on any
+ * given 'version'. */
+static inline const struct cls_match *
+next_visible_rule_in_list(const struct cls_match *rule, cls_version_t version)
+{
+ do {
+ rule = cls_match_next(rule);
+ } while (rule && !cls_match_visible_in_version(rule, version));
+
+ return rule;
+}
-static struct cls_match *next_rule_in_list__(struct cls_match *);
-static struct cls_match *next_rule_in_list(struct cls_match *);
+/* Type with maximum supported prefix length. */
+union trie_prefix {
+ struct in6_addr ipv6; /* For sizing. */
+ ovs_be32 be32; /* For access. */
+};
static unsigned int minimask_get_prefix_len(const struct minimask *,
const struct mf_field *);
-static void trie_init(struct cls_classifier *, int trie_idx,
+static void trie_init(struct classifier *cls, int trie_idx,
const struct mf_field *);
static unsigned int trie_lookup(const struct cls_trie *, const struct flow *,
- unsigned int *checkbits);
-static unsigned int trie_lookup_value(const struct trie_node *,
- const ovs_be32 value[],
- unsigned int value_bits,
- unsigned int *checkbits);
-static void trie_destroy(struct trie_node *);
+ union trie_prefix *plens);
+static unsigned int trie_lookup_value(const rcu_trie_ptr *,
+ const ovs_be32 value[], ovs_be32 plens[],
+ unsigned int value_bits);
+static void trie_destroy(rcu_trie_ptr *);
static void trie_insert(struct cls_trie *, const struct cls_rule *, int mlen);
-static void trie_insert_prefix(struct trie_node **, const ovs_be32 *prefix,
+static void trie_insert_prefix(rcu_trie_ptr *, const ovs_be32 *prefix,
int mlen);
static void trie_remove(struct cls_trie *, const struct cls_rule *, int mlen);
-static void trie_remove_prefix(struct trie_node **, const ovs_be32 *prefix,
+static void trie_remove_prefix(rcu_trie_ptr *, const ovs_be32 *prefix,
int mlen);
static void mask_set_prefix_bits(struct flow_wildcards *, uint8_t be32ofs,
- unsigned int nbits);
+ unsigned int n_bits);
static bool mask_prefix_bits_set(const struct flow_wildcards *,
- uint8_t be32ofs, unsigned int nbits);
+ uint8_t be32ofs, unsigned int n_bits);
\f
-/* flow/miniflow/minimask/minimatch utilities.
- * These are only used by the classifier, so place them here to allow
- * for better optimization. */
-
-static inline uint64_t
-miniflow_get_map_in_range(const struct miniflow *miniflow,
- uint8_t start, uint8_t end, unsigned int *offset)
-{
- uint64_t map = miniflow->map;
- *offset = 0;
-
- if (start > 0) {
- uint64_t msk = (UINT64_C(1) << start) - 1; /* 'start' LSBs set */
- *offset = count_1bits(map & msk);
- map &= ~msk;
- }
- if (end < FLOW_U32S) {
- uint64_t msk = (UINT64_C(1) << end) - 1; /* 'end' LSBs set */
- map &= msk;
- }
- return map;
-}
-
-/* Returns a hash value for the bits of 'flow' where there are 1-bits in
- * 'mask', given 'basis'.
- *
- * The hash values returned by this function are the same as those returned by
- * miniflow_hash_in_minimask(), only the form of the arguments differ. */
-static inline uint32_t
-flow_hash_in_minimask(const struct flow *flow, const struct minimask *mask,
- uint32_t basis)
-{
- const uint32_t *mask_values = miniflow_get_u32_values(&mask->masks);
- const uint32_t *flow_u32 = (const uint32_t *)flow;
- const uint32_t *p = mask_values;
- uint32_t hash;
- uint64_t map;
-
- hash = basis;
- for (map = mask->masks.map; map; map = zero_rightmost_1bit(map)) {
- hash = mhash_add(hash, flow_u32[raw_ctz(map)] & *p++);
- }
-
- return mhash_finish(hash, (p - mask_values) * 4);
-}
-
-/* Returns a hash value for the bits of 'flow' where there are 1-bits in
- * 'mask', given 'basis'.
- *
- * The hash values returned by this function are the same as those returned by
- * flow_hash_in_minimask(), only the form of the arguments differ. */
-static inline uint32_t
-miniflow_hash_in_minimask(const struct miniflow *flow,
- const struct minimask *mask, uint32_t basis)
-{
- const uint32_t *mask_values = miniflow_get_u32_values(&mask->masks);
- const uint32_t *p = mask_values;
- uint32_t hash = basis;
- uint32_t flow_u32;
-
- MINIFLOW_FOR_EACH_IN_MAP(flow_u32, flow, mask->masks.map) {
- hash = mhash_add(hash, flow_u32 & *p++);
- }
-
- return mhash_finish(hash, (p - mask_values) * 4);
-}
-
-/* Returns a hash value for the bits of range [start, end) in 'flow',
- * where there are 1-bits in 'mask', given 'hash'.
- *
- * The hash values returned by this function are the same as those returned by
- * minimatch_hash_range(), only the form of the arguments differ. */
-static inline uint32_t
-flow_hash_in_minimask_range(const struct flow *flow,
- const struct minimask *mask,
- uint8_t start, uint8_t end, uint32_t *basis)
-{
- const uint32_t *mask_values = miniflow_get_u32_values(&mask->masks);
- const uint32_t *flow_u32 = (const uint32_t *)flow;
- unsigned int offset;
- uint64_t map = miniflow_get_map_in_range(&mask->masks, start, end,
- &offset);
- const uint32_t *p = mask_values + offset;
- uint32_t hash = *basis;
-
- for (; map; map = zero_rightmost_1bit(map)) {
- hash = mhash_add(hash, flow_u32[raw_ctz(map)] & *p++);
- }
-
- *basis = hash; /* Allow continuation from the unfinished value. */
- return mhash_finish(hash, (p - mask_values) * 4);
-}
-
-/* Fold minimask 'mask''s wildcard mask into 'wc's wildcard mask. */
-static inline void
-flow_wildcards_fold_minimask(struct flow_wildcards *wc,
- const struct minimask *mask)
-{
- flow_union_with_miniflow(&wc->masks, &mask->masks);
-}
+/* cls_rule. */
-/* Fold minimask 'mask''s wildcard mask into 'wc's wildcard mask
- * in range [start, end). */
static inline void
-flow_wildcards_fold_minimask_range(struct flow_wildcards *wc,
- const struct minimask *mask,
- uint8_t start, uint8_t end)
+cls_rule_init__(struct cls_rule *rule, unsigned int priority)
{
- uint32_t *dst_u32 = (uint32_t *)&wc->masks;
- unsigned int offset;
- uint64_t map = miniflow_get_map_in_range(&mask->masks, start, end,
- &offset);
- const uint32_t *p = miniflow_get_u32_values(&mask->masks) + offset;
-
- for (; map; map = zero_rightmost_1bit(map)) {
- dst_u32[raw_ctz(map)] |= *p++;
- }
-}
-
-/* Returns a hash value for 'flow', given 'basis'. */
-static inline uint32_t
-miniflow_hash(const struct miniflow *flow, uint32_t basis)
-{
- const uint32_t *values = miniflow_get_u32_values(flow);
- const uint32_t *p = values;
- uint32_t hash = basis;
- uint64_t hash_map = 0;
- uint64_t map;
-
- for (map = flow->map; map; map = zero_rightmost_1bit(map)) {
- if (*p) {
- hash = mhash_add(hash, *p);
- hash_map |= rightmost_1bit(map);
- }
- p++;
- }
- hash = mhash_add(hash, hash_map);
- hash = mhash_add(hash, hash_map >> 32);
-
- return mhash_finish(hash, p - values);
-}
-
-/* Returns a hash value for 'mask', given 'basis'. */
-static inline uint32_t
-minimask_hash(const struct minimask *mask, uint32_t basis)
-{
- return miniflow_hash(&mask->masks, basis);
-}
-
-/* Returns a hash value for 'match', given 'basis'. */
-static inline uint32_t
-minimatch_hash(const struct minimatch *match, uint32_t basis)
-{
- return miniflow_hash(&match->flow, minimask_hash(&match->mask, basis));
-}
-
-/* Returns a hash value for the bits of range [start, end) in 'minimatch',
- * given 'basis'.
- *
- * The hash values returned by this function are the same as those returned by
- * flow_hash_in_minimask_range(), only the form of the arguments differ. */
-static inline uint32_t
-minimatch_hash_range(const struct minimatch *match, uint8_t start, uint8_t end,
- uint32_t *basis)
-{
- unsigned int offset;
- const uint32_t *p, *q;
- uint32_t hash = *basis;
- int n, i;
-
- n = count_1bits(miniflow_get_map_in_range(&match->mask.masks, start, end,
- &offset));
- q = miniflow_get_u32_values(&match->mask.masks) + offset;
- p = miniflow_get_u32_values(&match->flow) + offset;
-
- for (i = 0; i < n; i++) {
- hash = mhash_add(hash, p[i] & q[i]);
- }
- *basis = hash; /* Allow continuation from the unfinished value. */
- return mhash_finish(hash, (offset + n) * 4);
+ rculist_init(&rule->node);
+ *CONST_CAST(int *, &rule->priority) = priority;
+ rule->cls_match = NULL;
}
-\f
-/* cls_rule. */
-
/* Initializes 'rule' to match packets specified by 'match' at the given
* 'priority'. 'match' must satisfy the invariant described in the comment at
* the definition of struct match.
*
* The caller must eventually destroy 'rule' with cls_rule_destroy().
*
- * (OpenFlow uses priorities between 0 and UINT16_MAX, inclusive, but
- * internally Open vSwitch supports a wider range.) */
+ * Clients should not use priority INT_MIN. (OpenFlow uses priorities between
+ * 0 and UINT16_MAX, inclusive.) */
void
-cls_rule_init(struct cls_rule *rule,
- const struct match *match, unsigned int priority)
+cls_rule_init(struct cls_rule *rule, const struct match *match, int priority)
{
- minimatch_init(&rule->match, match);
- rule->priority = priority;
- rule->cls_match = NULL;
+ cls_rule_init__(rule, priority);
+ minimatch_init(CONST_CAST(struct minimatch *, &rule->match), match);
}
/* Same as cls_rule_init() for initialization from a "struct minimatch". */
void
cls_rule_init_from_minimatch(struct cls_rule *rule,
- const struct minimatch *match,
- unsigned int priority)
+ const struct minimatch *match, int priority)
{
- minimatch_clone(&rule->match, match);
- rule->priority = priority;
- rule->cls_match = NULL;
+ cls_rule_init__(rule, priority);
+ minimatch_clone(CONST_CAST(struct minimatch *, &rule->match), match);
}
/* Initializes 'dst' as a copy of 'src'.
void
cls_rule_clone(struct cls_rule *dst, const struct cls_rule *src)
{
- minimatch_clone(&dst->match, &src->match);
- dst->priority = src->priority;
- dst->cls_match = NULL;
+ cls_rule_init__(dst, src->priority);
+ minimatch_clone(CONST_CAST(struct minimatch *, &dst->match), &src->match);
}
/* Initializes 'dst' with the data in 'src', destroying 'src'.
+ *
+ * 'src' must be a cls_rule NOT in a classifier.
*
* The caller must eventually destroy 'dst' with cls_rule_destroy(). */
void
cls_rule_move(struct cls_rule *dst, struct cls_rule *src)
{
- minimatch_move(&dst->match, &src->match);
- dst->priority = src->priority;
- dst->cls_match = NULL;
+ cls_rule_init__(dst, src->priority);
+ minimatch_move(CONST_CAST(struct minimatch *, &dst->match),
+ CONST_CAST(struct minimatch *, &src->match));
}
/* Frees memory referenced by 'rule'. Doesn't free 'rule' itself (it's
* ('rule' must not currently be in a classifier.) */
void
cls_rule_destroy(struct cls_rule *rule)
+ OVS_NO_THREAD_SAFETY_ANALYSIS
{
- ovs_assert(!rule->cls_match);
- minimatch_destroy(&rule->match);
+ ovs_assert(!rule->cls_match); /* Must not be in a classifier. */
+
+ /* Check that the rule has been properly removed from the classifier. */
+ ovs_assert(rule->node.prev == RCULIST_POISON
+ || rculist_is_empty(&rule->node));
+ rculist_poison__(&rule->node); /* Poisons also the next pointer. */
+
+ minimatch_destroy(CONST_CAST(struct minimatch *, &rule->match));
}
+void
+cls_rule_set_conjunctions(struct cls_rule *cr,
+ const struct cls_conjunction *conj, size_t n)
+{
+ struct cls_match *match = cr->cls_match;
+ struct cls_conjunction_set *old
+ = ovsrcu_get_protected(struct cls_conjunction_set *, &match->conj_set);
+ struct cls_conjunction *old_conj = old ? old->conj : NULL;
+ unsigned int old_n = old ? old->n : 0;
+
+ if (old_n != n || (n && memcmp(old_conj, conj, n * sizeof *conj))) {
+ if (old) {
+ ovsrcu_postpone(free, old);
+ }
+ ovsrcu_set(&match->conj_set,
+ cls_conjunction_set_alloc(match, conj, n));
+ }
+}
+
+
/* Returns true if 'a' and 'b' match the same packets at the same priority,
* false if they differ in some way. */
bool
return a->priority == b->priority && minimatch_equal(&a->match, &b->match);
}
-/* Returns a hash value for 'rule', folding in 'basis'. */
-uint32_t
-cls_rule_hash(const struct cls_rule *rule, uint32_t basis)
-{
- return minimatch_hash(&rule->match, hash_int(rule->priority, basis));
-}
-
/* Appends a string describing 'rule' to 's'. */
void
cls_rule_format(const struct cls_rule *rule, struct ds *s)
bool
cls_rule_is_catchall(const struct cls_rule *rule)
{
- return minimask_is_catchall(&rule->match.mask);
+ return minimask_is_catchall(rule->match.mask);
}
-\f
-/* Initializes 'cls' as a classifier that initially contains no classification
- * rules. */
+
+/* Makes 'rule' invisible in 'remove_version'. Once that version is used in
+ * lookups, the caller should remove 'rule' via ovsrcu_postpone().
+ *
+ * 'rule' must be in a classifier. */
void
-classifier_init(struct classifier *cls_, const uint8_t *flow_segments)
+cls_rule_make_invisible_in_version(const struct cls_rule *rule,
+ cls_version_t remove_version)
{
- struct cls_classifier *cls = xmalloc(sizeof *cls);
+ ovs_assert(remove_version >= rule->cls_match->add_version);
- fat_rwlock_init(&cls_->rwlock);
+ cls_match_set_remove_version(rule->cls_match, remove_version);
+}
- cls_->cls = cls;
+/* This undoes the change made by cls_rule_make_invisible_in_version().
+ *
+ * 'rule' must be in a classifier. */
+void
+cls_rule_restore_visibility(const struct cls_rule *rule)
+{
+ cls_match_set_remove_version(rule->cls_match, CLS_NOT_REMOVED_VERSION);
+}
+/* Return true if 'rule' is visible in 'version'.
+ *
+ * 'rule' must be in a classifier. */
+bool
+cls_rule_visible_in_version(const struct cls_rule *rule, cls_version_t version)
+{
+ return cls_match_visible_in_version(rule->cls_match, version);
+}
+\f
+/* Initializes 'cls' as a classifier that initially contains no classification
+ * rules. */
+void
+classifier_init(struct classifier *cls, const uint8_t *flow_segments)
+{
cls->n_rules = 0;
- hmap_init(&cls->subtables_map);
+ cmap_init(&cls->subtables_map);
pvector_init(&cls->subtables);
- hmap_init(&cls->partitions);
cls->n_flow_segments = 0;
if (flow_segments) {
while (cls->n_flow_segments < CLS_MAX_INDICES
- && *flow_segments < FLOW_U32S) {
+ && *flow_segments < FLOW_U64S) {
cls->flow_segments[cls->n_flow_segments++] = *flow_segments++;
}
}
cls->n_tries = 0;
+ for (int i = 0; i < CLS_MAX_TRIES; i++) {
+ trie_init(cls, i, NULL);
+ }
+ cls->publish = true;
}
/* Destroys 'cls'. Rules within 'cls', if any, are not freed; this is the
- * caller's responsibility. */
+ * caller's responsibility.
+ * May only be called after all the readers have been terminated. */
void
-classifier_destroy(struct classifier *cls_)
+classifier_destroy(struct classifier *cls)
{
- if (cls_) {
- struct cls_classifier *cls = cls_->cls;
- struct cls_partition *partition, *next_partition;
- struct cls_subtable *subtable, *next_subtable;
+ if (cls) {
+ struct cls_subtable *subtable;
int i;
- fat_rwlock_destroy(&cls_->rwlock);
- if (!cls) {
- return;
- }
-
for (i = 0; i < cls->n_tries; i++) {
- trie_destroy(cls->tries[i].root);
+ trie_destroy(&cls->tries[i].root);
}
- HMAP_FOR_EACH_SAFE (subtable, next_subtable, hmap_node,
- &cls->subtables_map) {
+ CMAP_FOR_EACH (subtable, cmap_node, &cls->subtables_map) {
destroy_subtable(cls, subtable);
}
- hmap_destroy(&cls->subtables_map);
-
- HMAP_FOR_EACH_SAFE (partition, next_partition, hmap_node,
- &cls->partitions) {
- hmap_remove(&cls->partitions, &partition->hmap_node);
- free(partition);
- }
- hmap_destroy(&cls->partitions);
+ cmap_destroy(&cls->subtables_map);
pvector_destroy(&cls->subtables);
- free(cls);
}
}
-/* We use uint64_t as a set for the fields below. */
-BUILD_ASSERT_DECL(MFF_N_IDS <= 64);
-
/* Set the fields for which prefix lookup should be performed. */
-void
-classifier_set_prefix_fields(struct classifier *cls_,
+bool
+classifier_set_prefix_fields(struct classifier *cls,
const enum mf_field_id *trie_fields,
unsigned int n_fields)
{
- struct cls_classifier *cls = cls_->cls;
- uint64_t fields = 0;
- int i, trie;
+ const struct mf_field * new_fields[CLS_MAX_TRIES];
+ struct mf_bitmap fields = MF_BITMAP_INITIALIZER;
+ int i, n_tries = 0;
+ bool changed = false;
- for (i = 0, trie = 0; i < n_fields && trie < CLS_MAX_TRIES; i++) {
+ for (i = 0; i < n_fields && n_tries < CLS_MAX_TRIES; i++) {
const struct mf_field *field = mf_from_id(trie_fields[i]);
if (field->flow_be32ofs < 0 || field->n_bits % 32) {
/* Incompatible field. This is the only place where we
continue;
}
- if (fields & (UINT64_C(1) << trie_fields[i])) {
+ if (bitmap_is_set(fields.bm, trie_fields[i])) {
/* Duplicate field, there is no need to build more than
* one index for any one field. */
continue;
}
- fields |= UINT64_C(1) << trie_fields[i];
+ bitmap_set1(fields.bm, trie_fields[i]);
- if (trie >= cls->n_tries || field != cls->tries[trie].field) {
- trie_init(cls, trie, field);
+ new_fields[n_tries] = NULL;
+ if (n_tries >= cls->n_tries || field != cls->tries[n_tries].field) {
+ new_fields[n_tries] = field;
+ changed = true;
+ }
+ n_tries++;
+ }
+
+ if (changed || n_tries < cls->n_tries) {
+ struct cls_subtable *subtable;
+
+ /* Trie configuration needs to change. Disable trie lookups
+ * for the tries that are changing and wait all the current readers
+ * with the old configuration to be done. */
+ changed = false;
+ CMAP_FOR_EACH (subtable, cmap_node, &cls->subtables_map) {
+ for (i = 0; i < cls->n_tries; i++) {
+ if ((i < n_tries && new_fields[i]) || i >= n_tries) {
+ if (subtable->trie_plen[i]) {
+ subtable->trie_plen[i] = 0;
+ changed = true;
+ }
+ }
+ }
+ }
+ /* Synchronize if any readers were using tries. The readers may
+ * temporarily function without the trie lookup based optimizations. */
+ if (changed) {
+ /* ovsrcu_synchronize() functions as a memory barrier, so it does
+ * not matter that subtable->trie_plen is not atomic. */
+ ovsrcu_synchronize();
}
- trie++;
- }
- /* Destroy the rest. */
- for (i = trie; i < cls->n_tries; i++) {
- trie_init(cls, i, NULL);
+ /* Now set up the tries. */
+ for (i = 0; i < n_tries; i++) {
+ if (new_fields[i]) {
+ trie_init(cls, i, new_fields[i]);
+ }
+ }
+ /* Destroy the rest, if any. */
+ for (; i < cls->n_tries; i++) {
+ trie_init(cls, i, NULL);
+ }
+
+ cls->n_tries = n_tries;
+ return true;
}
- cls->n_tries = trie;
+
+ return false; /* No change. */
}
static void
-trie_init(struct cls_classifier *cls, int trie_idx,
- const struct mf_field *field)
+trie_init(struct classifier *cls, int trie_idx, const struct mf_field *field)
{
struct cls_trie *trie = &cls->tries[trie_idx];
struct cls_subtable *subtable;
if (trie_idx < cls->n_tries) {
- trie_destroy(trie->root);
+ trie_destroy(&trie->root);
+ } else {
+ ovsrcu_set_hidden(&trie->root, NULL);
}
- trie->root = NULL;
trie->field = field;
- /* Add existing rules to the trie. */
- HMAP_FOR_EACH (subtable, hmap_node, &cls->subtables_map) {
+ /* Add existing rules to the new trie. */
+ CMAP_FOR_EACH (subtable, cmap_node, &cls->subtables_map) {
unsigned int plen;
plen = field ? minimask_get_prefix_len(&subtable->mask, field) : 0;
- /* Initialize subtable's prefix length on this field. */
- subtable->trie_plen[trie_idx] = plen;
-
if (plen) {
struct cls_match *head;
- HMAP_FOR_EACH (head, hmap_node, &subtable->rules) {
- struct cls_match *match;
-
- FOR_EACH_RULE_IN_LIST (match, head) {
- trie_insert(trie, match->cls_rule, plen);
- }
+ CMAP_FOR_EACH (head, cmap_node, &subtable->rules) {
+ trie_insert(trie, head->cls_rule, plen);
}
}
+ /* Initialize subtable's prefix length on this field. This will
+ * allow readers to use the trie. */
+ atomic_thread_fence(memory_order_release);
+ subtable->trie_plen[trie_idx] = plen;
}
}
-/* Returns true if 'cls' contains no classification rules, false otherwise. */
+/* Returns true if 'cls' contains no classification rules, false otherwise.
+ * Checking the cmap requires no locking. */
bool
classifier_is_empty(const struct classifier *cls)
{
- return cls->cls->n_rules == 0;
+ return cmap_is_empty(&cls->subtables_map);
}
/* Returns the number of rules in 'cls'. */
int
classifier_count(const struct classifier *cls)
{
- return cls->cls->n_rules;
+ /* n_rules is an int, so in the presence of concurrent writers this will
+ * return either the old or a new value. */
+ return cls->n_rules;
}
-static uint32_t
-hash_metadata(ovs_be64 metadata_)
+static inline ovs_be32 minimatch_get_ports(const struct minimatch *match)
{
- uint64_t metadata = (OVS_FORCE uint64_t) metadata_;
- return hash_uint64(metadata);
+ /* Could optimize to use the same map if needed for fast path. */
+ return MINIFLOW_GET_BE32(match->flow, tp_src)
+ & MINIFLOW_GET_BE32(&match->mask->masks, tp_src);
}
-static struct cls_partition *
-find_partition(const struct cls_classifier *cls, ovs_be64 metadata,
- uint32_t hash)
+static void
+subtable_replace_head_rule(struct classifier *cls OVS_UNUSED,
+ struct cls_subtable *subtable,
+ struct cls_match *head, struct cls_match *new,
+ uint32_t hash, uint32_t ihash[CLS_MAX_INDICES])
{
- struct cls_partition *partition;
+ /* Rule's data is already in the tries. */
- HMAP_FOR_EACH_IN_BUCKET (partition, hmap_node, hash, &cls->partitions) {
- if (partition->metadata == metadata) {
- return partition;
- }
+ for (int i = 0; i < subtable->n_indices; i++) {
+ cmap_replace(&subtable->indices[i], &head->index_nodes[i],
+ &new->index_nodes[i], ihash[i]);
}
-
- return NULL;
+ cmap_replace(&subtable->rules, &head->cmap_node, &new->cmap_node, hash);
}
-static struct cls_partition *
-create_partition(struct cls_classifier *cls, struct cls_subtable *subtable,
- ovs_be64 metadata)
-{
- uint32_t hash = hash_metadata(metadata);
- struct cls_partition *partition = find_partition(cls, metadata, hash);
- if (!partition) {
- partition = xmalloc(sizeof *partition);
- partition->metadata = metadata;
- partition->tags = 0;
- tag_tracker_init(&partition->tracker);
- hmap_insert(&cls->partitions, &partition->hmap_node, hash);
- }
- tag_tracker_add(&partition->tracker, &partition->tags, subtable->tag);
- return partition;
-}
-
-static inline ovs_be32 minimatch_get_ports(const struct minimatch *match)
-{
- /* Could optimize to use the same map if needed for fast path. */
- return MINIFLOW_GET_BE32(&match->flow, tp_src)
- & MINIFLOW_GET_BE32(&match->mask.masks, tp_src);
-}
-
-/* Inserts 'rule' into 'cls'. Until 'rule' is removed from 'cls', the caller
- * must not modify or free it.
+/* Inserts 'rule' into 'cls' in 'version'. Until 'rule' is removed from 'cls',
+ * the caller must not modify or free it.
*
* If 'cls' already contains an identical rule (including wildcards, values of
- * fixed fields, and priority), replaces the old rule by 'rule' and returns the
- * rule that was replaced. The caller takes ownership of the returned rule and
- * is thus responsible for destroying it with cls_rule_destroy(), freeing the
- * memory block in which it resides, etc., as necessary.
+ * fixed fields, and priority) that is visible in 'version', replaces the old
+ * rule by 'rule' and returns the rule that was replaced. The caller takes
+ * ownership of the returned rule and is thus responsible for destroying it
+ * with cls_rule_destroy(), after RCU grace period has passed (see
+ * ovsrcu_postpone()).
*
* Returns NULL if 'cls' does not contain a rule with an identical key, after
* inserting the new rule. In this case, no rules are displaced by the new
* rule, even rules that cannot have any effect because the new rule matches a
- * superset of their flows and has higher priority. */
-struct cls_rule *
-classifier_replace(struct classifier *cls_, struct cls_rule *rule)
+ * superset of their flows and has higher priority.
+ */
+const struct cls_rule *
+classifier_replace(struct classifier *cls, const struct cls_rule *rule,
+ cls_version_t version,
+ const struct cls_conjunction *conjs, size_t n_conjs)
{
- struct cls_classifier *cls = cls_->cls;
- struct cls_match *old_rule;
+ struct cls_match *new;
struct cls_subtable *subtable;
+ uint32_t ihash[CLS_MAX_INDICES];
+ struct cls_match *head;
+ unsigned int mask_offset;
+ size_t n_rules = 0;
+ uint32_t basis;
+ uint32_t hash;
+ unsigned int i;
- subtable = find_subtable(cls, &rule->match.mask);
- if (!subtable) {
- subtable = insert_subtable(cls, &rule->match.mask);
- }
+ /* 'new' is initially invisible to lookups. */
+ new = cls_match_alloc(rule, version, conjs, n_conjs);
- old_rule = insert_rule(cls, subtable, rule);
- if (!old_rule) {
- int i;
+ CONST_CAST(struct cls_rule *, rule)->cls_match = new;
- rule->cls_match->partition = NULL;
- if (minimask_get_metadata_mask(&rule->match.mask) == OVS_BE64_MAX) {
- ovs_be64 metadata = miniflow_get_metadata(&rule->match.flow);
- rule->cls_match->partition = create_partition(cls, subtable,
- metadata);
- }
+ subtable = find_subtable(cls, rule->match.mask);
+ if (!subtable) {
+ subtable = insert_subtable(cls, rule->match.mask);
+ }
- cls->n_rules++;
+ /* Compute hashes in segments. */
+ basis = 0;
+ mask_offset = 0;
+ for (i = 0; i < subtable->n_indices; i++) {
+ ihash[i] = minimatch_hash_range(&rule->match, subtable->index_maps[i],
+ &mask_offset, &basis);
+ }
+ hash = minimatch_hash_range(&rule->match, subtable->index_maps[i],
+ &mask_offset, &basis);
+ head = find_equal(subtable, rule->match.flow, hash);
+ if (!head) {
+ /* Add rule to tries.
+ *
+ * Concurrent readers might miss seeing the rule until this update,
+ * which might require being fixed up by revalidation later. */
for (i = 0; i < cls->n_tries; i++) {
if (subtable->trie_plen[i]) {
trie_insert(&cls->tries[i], rule, subtable->trie_plen[i]);
}
}
- /* Ports trie. */
+ /* Add rule to ports trie. */
if (subtable->ports_mask_len) {
/* We mask the value to be inserted to always have the wildcarded
* bits in known (zero) state, so we can include them in comparison
subtable->ports_mask_len);
}
- return NULL;
- } else {
- struct cls_rule *old_cls_rule = old_rule->cls_rule;
+ /* Add new node to segment indices.
+ *
+ * Readers may find the rule in the indices before the rule is visible
+ * in the subtables 'rules' map. This may result in us losing the
+ * opportunity to quit lookups earlier, resulting in sub-optimal
+ * wildcarding. This will be fixed later by revalidation (always
+ * scheduled after flow table changes). */
+ for (i = 0; i < subtable->n_indices; i++) {
+ cmap_insert(&subtable->indices[i], &new->index_nodes[i], ihash[i]);
+ }
+ n_rules = cmap_insert(&subtable->rules, &new->cmap_node, hash);
+ } else { /* Equal rules exist in the classifier already. */
+ struct cls_match *prev, *iter;
- rule->cls_match->partition = old_rule->partition;
- old_cls_rule->cls_match = NULL;
- free(old_rule);
- return old_cls_rule;
+ /* Scan the list for the insertion point that will keep the list in
+ * order of decreasing priority. Insert after rules marked invisible
+ * in any version of the same priority. */
+ FOR_EACH_RULE_IN_LIST_PROTECTED (iter, prev, head) {
+ if (rule->priority > iter->priority
+ || (rule->priority == iter->priority
+ && !cls_match_is_eventually_invisible(iter))) {
+ break;
+ }
+ }
+
+ /* Replace 'iter' with 'new' or insert 'new' between 'prev' and
+ * 'iter'. */
+ if (iter) {
+ struct cls_rule *old;
+
+ if (rule->priority == iter->priority) {
+ cls_match_replace(prev, iter, new);
+ old = CONST_CAST(struct cls_rule *, iter->cls_rule);
+ } else {
+ cls_match_insert(prev, iter, new);
+ old = NULL;
+ }
+
+ /* Replace the existing head in data structures, if rule is the new
+ * head. */
+ if (iter == head) {
+ subtable_replace_head_rule(cls, subtable, head, new, hash,
+ ihash);
+ }
+
+ if (old) {
+ struct cls_conjunction_set *conj_set;
+
+ conj_set = ovsrcu_get_protected(struct cls_conjunction_set *,
+ &iter->conj_set);
+ if (conj_set) {
+ ovsrcu_postpone(free, conj_set);
+ }
+
+ ovsrcu_postpone(cls_match_free_cb, iter);
+ old->cls_match = NULL;
+
+ /* No change in subtable's max priority or max count. */
+
+ /* Make 'new' visible to lookups in the appropriate version. */
+ cls_match_set_remove_version(new, CLS_NOT_REMOVED_VERSION);
+
+ /* Make rule visible to iterators (immediately). */
+ rculist_replace(CONST_CAST(struct rculist *, &rule->node),
+ &old->node);
+
+ /* Return displaced rule. Caller is responsible for keeping it
+ * around until all threads quiesce. */
+ return old;
+ }
+ } else {
+ /* 'new' is new node after 'prev' */
+ cls_match_insert(prev, iter, new);
+ }
+ }
+
+ /* Make 'new' visible to lookups in the appropriate version. */
+ cls_match_set_remove_version(new, CLS_NOT_REMOVED_VERSION);
+
+ /* Make rule visible to iterators (immediately). */
+ rculist_push_back(&subtable->rules_list,
+ CONST_CAST(struct rculist *, &rule->node));
+
+ /* Rule was added, not replaced. Update 'subtable's 'max_priority' and
+ * 'max_count', if necessary.
+ *
+ * The rule was already inserted, but concurrent readers may not see the
+ * rule yet as the subtables vector is not updated yet. This will have to
+ * be fixed by revalidation later. */
+ if (n_rules == 1) {
+ subtable->max_priority = rule->priority;
+ subtable->max_count = 1;
+ pvector_insert(&cls->subtables, subtable, rule->priority);
+ } else if (rule->priority == subtable->max_priority) {
+ ++subtable->max_count;
+ } else if (rule->priority > subtable->max_priority) {
+ subtable->max_priority = rule->priority;
+ subtable->max_count = 1;
+ pvector_change_priority(&cls->subtables, subtable, rule->priority);
}
+
+ /* Nothing was replaced. */
+ cls->n_rules++;
+
+ if (cls->publish) {
+ pvector_publish(&cls->subtables);
+ }
+
+ return NULL;
}
/* Inserts 'rule' into 'cls'. Until 'rule' is removed from 'cls', the caller
* fixed fields, and priority). Use classifier_find_rule_exactly() to find
* such a rule. */
void
-classifier_insert(struct classifier *cls, struct cls_rule *rule)
+classifier_insert(struct classifier *cls, const struct cls_rule *rule,
+ cls_version_t version, const struct cls_conjunction conj[],
+ size_t n_conj)
{
- struct cls_rule *displaced_rule = classifier_replace(cls, rule);
+ const struct cls_rule *displaced_rule
+ = classifier_replace(cls, rule, version, conj, n_conj);
ovs_assert(!displaced_rule);
}
/* Removes 'rule' from 'cls'. It is the caller's responsibility to destroy
* 'rule' with cls_rule_destroy(), freeing the memory block in which 'rule'
- * resides, etc., as necessary. */
-void
-classifier_remove(struct classifier *cls_, struct cls_rule *rule)
+ * resides, etc., as necessary.
+ *
+ * Does nothing if 'rule' has been already removed, or was never inserted.
+ *
+ * Returns the removed rule, or NULL, if it was already removed.
+ */
+const struct cls_rule *
+classifier_remove(struct classifier *cls, const struct cls_rule *cls_rule)
{
- struct cls_classifier *cls = cls_->cls;
- struct cls_partition *partition;
- struct cls_match *cls_match = rule->cls_match;
- struct cls_match *head;
+ struct cls_match *rule, *prev, *next, *head;
+ struct cls_conjunction_set *conj_set;
struct cls_subtable *subtable;
- int i;
+ uint32_t basis = 0, hash, ihash[CLS_MAX_INDICES];
+ unsigned int mask_offset;
+ size_t n_rules;
+ unsigned int i;
+
+ rule = cls_rule->cls_match;
+ if (!rule) {
+ return NULL;
+ }
+ /* Mark as removed. */
+ CONST_CAST(struct cls_rule *, cls_rule)->cls_match = NULL;
- ovs_assert(cls_match);
+ /* Remove 'cls_rule' from the subtable's rules list. */
+ rculist_remove(CONST_CAST(struct rculist *, &cls_rule->node));
- subtable = find_subtable(cls, &rule->match.mask);
+ subtable = find_subtable(cls, cls_rule->match.mask);
ovs_assert(subtable);
+ mask_offset = 0;
+ for (i = 0; i < subtable->n_indices; i++) {
+ ihash[i] = minimatch_hash_range(&cls_rule->match,
+ subtable->index_maps[i],
+ &mask_offset, &basis);
+ }
+ hash = minimatch_hash_range(&cls_rule->match, subtable->index_maps[i],
+ &mask_offset, &basis);
+
+ head = find_equal(subtable, cls_rule->match.flow, hash);
+
+ /* Check if the rule is not the head rule. */
+ if (rule != head) {
+ struct cls_match *iter;
+
+ /* Not the head rule, but potentially one with the same priority. */
+ /* Remove from the list of equal rules. */
+ FOR_EACH_RULE_IN_LIST_PROTECTED (iter, prev, head) {
+ if (rule == iter) {
+ break;
+ }
+ }
+ ovs_assert(iter == rule);
+
+ cls_match_remove(prev, rule);
+
+ goto check_priority;
+ }
+
+ /* 'rule' is the head rule. Check if there is another rule to
+ * replace 'rule' in the data structures. */
+ next = cls_match_next_protected(rule);
+ if (next) {
+ subtable_replace_head_rule(cls, subtable, rule, next, hash, ihash);
+ goto check_priority;
+ }
+
+ /* 'rule' is last of the kind in the classifier, must remove from all the
+ * data structures. */
+
if (subtable->ports_mask_len) {
- ovs_be32 masked_ports = minimatch_get_ports(&rule->match);
+ ovs_be32 masked_ports = minimatch_get_ports(&cls_rule->match);
trie_remove_prefix(&subtable->ports_trie,
&masked_ports, subtable->ports_mask_len);
}
for (i = 0; i < cls->n_tries; i++) {
if (subtable->trie_plen[i]) {
- trie_remove(&cls->tries[i], rule, subtable->trie_plen[i]);
+ trie_remove(&cls->tries[i], cls_rule, subtable->trie_plen[i]);
}
}
/* Remove rule node from indices. */
for (i = 0; i < subtable->n_indices; i++) {
- hindex_remove(&subtable->indices[i], &cls_match->index_nodes[i]);
+ cmap_remove(&subtable->indices[i], &rule->index_nodes[i], ihash[i]);
}
+ n_rules = cmap_remove(&subtable->rules, &rule->cmap_node, hash);
- head = find_equal(subtable, &rule->match.flow, cls_match->hmap_node.hash);
- if (head != cls_match) {
- list_remove(&cls_match->list);
- } else if (list_is_empty(&cls_match->list)) {
- hmap_remove(&subtable->rules, &cls_match->hmap_node);
+ if (n_rules == 0) {
+ destroy_subtable(cls, subtable);
} else {
- struct cls_match *next = CONTAINER_OF(cls_match->list.next,
- struct cls_match, list);
-
- list_remove(&cls_match->list);
- hmap_replace(&subtable->rules, &cls_match->hmap_node,
- &next->hmap_node);
- }
+check_priority:
+ if (subtable->max_priority == rule->priority
+ && --subtable->max_count == 0) {
+ /* Find the new 'max_priority' and 'max_count'. */
+ int max_priority = INT_MIN;
+ struct cls_match *head;
- partition = cls_match->partition;
- if (partition) {
- tag_tracker_subtract(&partition->tracker, &partition->tags,
- subtable->tag);
- if (!partition->tags) {
- hmap_remove(&cls->partitions, &partition->hmap_node);
- free(partition);
+ CMAP_FOR_EACH (head, cmap_node, &subtable->rules) {
+ if (head->priority > max_priority) {
+ max_priority = head->priority;
+ subtable->max_count = 1;
+ } else if (head->priority == max_priority) {
+ ++subtable->max_count;
+ }
+ }
+ subtable->max_priority = max_priority;
+ pvector_change_priority(&cls->subtables, subtable, max_priority);
}
}
- if (--subtable->n_rules == 0) {
- destroy_subtable(cls, subtable);
- } else if (subtable->max_priority == cls_match->priority
- && --subtable->max_count == 0) {
- /* Find the new 'max_priority' and 'max_count'. */
- struct cls_match *head;
- unsigned int max_priority = 0;
-
- HMAP_FOR_EACH (head, hmap_node, &subtable->rules) {
- if (head->priority > max_priority) {
- max_priority = head->priority;
- subtable->max_count = 1;
- } else if (head->priority == max_priority) {
- ++subtable->max_count;
- }
- }
- subtable->max_priority = max_priority;
- pvector_change_priority(&cls->subtables, subtable, max_priority);
+ if (cls->publish) {
+ pvector_publish(&cls->subtables);
}
+ /* free the rule. */
+ conj_set = ovsrcu_get_protected(struct cls_conjunction_set *,
+ &rule->conj_set);
+ if (conj_set) {
+ ovsrcu_postpone(free, conj_set);
+ }
+ ovsrcu_postpone(cls_match_free_cb, rule);
cls->n_rules--;
- rule->cls_match = NULL;
- free(cls_match);
+ return cls_rule;
}
/* Prefix tree context. Valid when 'lookup_done' is true. Can skip all
- * subtables which have more than 'match_plen' bits in their corresponding
- * field at offset 'be32ofs'. If skipped, 'maskbits' prefix bits should be
- * unwildcarded to quarantee datapath flow matches only packets it should. */
+ * subtables which have a prefix match on the trie field, but whose prefix
+ * length is not indicated in 'match_plens'. For example, a subtable that
+ * has a 8-bit trie field prefix match can be skipped if
+ * !be_get_bit_at(&match_plens, 8 - 1). If skipped, 'maskbits' prefix bits
+ * must be unwildcarded to make datapath flow only match packets it should. */
struct trie_ctx {
const struct cls_trie *trie;
bool lookup_done; /* Status of the lookup. */
uint8_t be32ofs; /* U32 offset of the field in question. */
- unsigned int match_plen; /* Longest prefix than could possibly match. */
unsigned int maskbits; /* Prefix length needed to avoid false matches. */
+ union trie_prefix match_plens; /* Bitmask of prefix lengths with possible
+ * matches. */
};
static void
ctx->lookup_done = false;
}
-/* Finds and returns the highest-priority rule in 'cls' that matches 'flow'.
- * Returns a null pointer if no rules in 'cls' match 'flow'. If multiple rules
- * of equal priority match 'flow', returns one arbitrarily.
- *
- * If a rule is found and 'wc' is non-null, bitwise-OR's 'wc' with the
- * set of bits that were significant in the lookup. At some point
- * earlier, 'wc' should have been initialized (e.g., by
- * flow_wildcards_init_catchall()). */
-struct cls_rule *
-classifier_lookup(const struct classifier *cls_, const struct flow *flow,
- struct flow_wildcards *wc)
-{
- struct cls_classifier *cls = cls_->cls;
- const struct cls_partition *partition;
- tag_type tags;
- int64_t best_priority = -1;
- const struct cls_match *best;
- struct trie_ctx trie_ctx[CLS_MAX_TRIES];
- struct cls_subtable *subtable;
+struct conjunctive_match {
+ struct hmap_node hmap_node;
+ uint32_t id;
+ uint64_t clauses;
+};
- /* Determine 'tags' such that, if 'subtable->tag' doesn't intersect them,
- * then 'flow' cannot possibly match in 'subtable':
- *
- * - If flow->metadata maps to a given 'partition', then we can use
- * 'tags' for 'partition->tags'.
- *
- * - If flow->metadata has no partition, then no rule in 'cls' has an
- * exact-match for flow->metadata. That means that we don't need to
- * search any subtable that includes flow->metadata in its mask.
- *
- * In either case, we always need to search any cls_subtables that do not
- * include flow->metadata in its mask. One way to do that would be to
- * check the "cls_subtable"s explicitly for that, but that would require an
- * extra branch per subtable. Instead, we mark such a cls_subtable's
- * 'tags' as TAG_ALL and make sure that 'tags' is never empty. This means
- * that 'tags' always intersects such a cls_subtable's 'tags', so we don't
- * need a special case.
- */
- partition = (hmap_is_empty(&cls->partitions)
- ? NULL
- : find_partition(cls, flow->metadata,
- hash_metadata(flow->metadata)));
- tags = partition ? partition->tags : TAG_ARBITRARY;
-
- /* Initialize trie contexts for match_find_wc(). */
- for (int i = 0; i < cls->n_tries; i++) {
- trie_ctx_init(&trie_ctx[i], &cls->tries[i]);
+static struct conjunctive_match *
+find_conjunctive_match__(struct hmap *matches, uint64_t id, uint32_t hash)
+{
+ struct conjunctive_match *m;
+
+ HMAP_FOR_EACH_IN_BUCKET (m, hmap_node, hash, matches) {
+ if (m->id == id) {
+ return m;
+ }
+ }
+ return NULL;
+}
+
+static bool
+find_conjunctive_match(const struct cls_conjunction_set *set,
+ unsigned int max_n_clauses, struct hmap *matches,
+ struct conjunctive_match *cm_stubs, size_t n_cm_stubs,
+ uint32_t *idp)
+{
+ const struct cls_conjunction *c;
+
+ if (max_n_clauses < set->min_n_clauses) {
+ return false;
}
- best = NULL;
- PVECTOR_FOR_EACH_PRIORITY(subtable, best_priority, 2,
- sizeof(struct cls_subtable), &cls->subtables) {
- struct cls_match *rule;
+ for (c = set->conj; c < &set->conj[set->n]; c++) {
+ struct conjunctive_match *cm;
+ uint32_t hash;
- if (!tag_intersects(tags, subtable->tag)) {
+ if (c->n_clauses > max_n_clauses) {
continue;
}
- rule = find_match_wc(subtable, flow, trie_ctx, cls->n_tries, wc);
- if (rule && (int64_t)rule->priority > best_priority) {
- best_priority = (int64_t)rule->priority;
- best = rule;
+ hash = hash_int(c->id, 0);
+ cm = find_conjunctive_match__(matches, c->id, hash);
+ if (!cm) {
+ size_t n = hmap_count(matches);
+
+ cm = n < n_cm_stubs ? &cm_stubs[n] : xmalloc(sizeof *cm);
+ hmap_insert(matches, &cm->hmap_node, hash);
+ cm->id = c->id;
+ cm->clauses = UINT64_MAX << (c->n_clauses & 63);
+ }
+ cm->clauses |= UINT64_C(1) << c->clause;
+ if (cm->clauses == UINT64_MAX) {
+ *idp = cm->id;
+ return true;
}
}
-
- return best ? best->cls_rule : NULL;
+ return false;
}
-/* Returns true if 'target' satisifies 'match', that is, if each bit for which
- * 'match' specifies a particular value has the correct value in 'target'.
- *
- * 'flow' and 'mask' have the same mask! */
-static bool
-miniflow_and_mask_matches_miniflow(const struct miniflow *flow,
- const struct minimask *mask,
- const struct miniflow *target)
+static void
+free_conjunctive_matches(struct hmap *matches,
+ struct conjunctive_match *cm_stubs, size_t n_cm_stubs)
{
- const uint32_t *flowp = miniflow_get_u32_values(flow);
- const uint32_t *maskp = miniflow_get_u32_values(&mask->masks);
- uint32_t target_u32;
+ if (hmap_count(matches) > n_cm_stubs) {
+ struct conjunctive_match *cm, *next;
- MINIFLOW_FOR_EACH_IN_MAP(target_u32, target, mask->masks.map) {
- if ((*flowp++ ^ target_u32) & *maskp++) {
- return false;
+ HMAP_FOR_EACH_SAFE (cm, next, hmap_node, matches) {
+ if (!(cm >= cm_stubs && cm < &cm_stubs[n_cm_stubs])) {
+ free(cm);
+ }
}
}
-
- return true;
+ hmap_destroy(matches);
}
-static inline struct cls_match *
-find_match_miniflow(const struct cls_subtable *subtable,
- const struct miniflow *flow,
- uint32_t hash)
+/* Like classifier_lookup(), except that support for conjunctive matches can be
+ * configured with 'allow_conjunctive_matches'. That feature is not exposed
+ * externally because turning off conjunctive matches is only useful to avoid
+ * recursion within this function itself.
+ *
+ * 'flow' is non-const to allow for temporary modifications during the lookup.
+ * Any changes are restored before returning. */
+static const struct cls_rule *
+classifier_lookup__(const struct classifier *cls, cls_version_t version,
+ struct flow *flow, struct flow_wildcards *wc,
+ bool allow_conjunctive_matches)
{
- struct cls_match *rule;
+ struct trie_ctx trie_ctx[CLS_MAX_TRIES];
+ const struct cls_match *match;
+ /* Highest-priority flow in 'cls' that certainly matches 'flow'. */
+ const struct cls_match *hard = NULL;
+ int hard_pri = INT_MIN; /* hard ? hard->priority : INT_MIN. */
+
+ /* Highest-priority conjunctive flows in 'cls' matching 'flow'. Since
+ * these are (components of) conjunctive flows, we can only know whether
+ * the full conjunctive flow matches after seeing multiple of them. Thus,
+ * we refer to these as "soft matches". */
+ struct cls_conjunction_set *soft_stub[64];
+ struct cls_conjunction_set **soft = soft_stub;
+ size_t n_soft = 0, allocated_soft = ARRAY_SIZE(soft_stub);
+ int soft_pri = INT_MIN; /* n_soft ? MAX(soft[*]->priority) : INT_MIN. */
+
+ /* Synchronize for cls->n_tries and subtable->trie_plen. They can change
+ * when table configuration changes, which happens typically only on
+ * startup. */
+ atomic_thread_fence(memory_order_acquire);
+
+ /* Initialize trie contexts for find_match_wc(). */
+ for (int i = 0; i < cls->n_tries; i++) {
+ trie_ctx_init(&trie_ctx[i], &cls->tries[i]);
+ }
- HMAP_FOR_EACH_WITH_HASH (rule, hmap_node, hash, &subtable->rules) {
- if (miniflow_and_mask_matches_miniflow(&rule->flow, &subtable->mask,
- flow)) {
- return rule;
+ /* Main loop. */
+ struct cls_subtable *subtable;
+ PVECTOR_FOR_EACH_PRIORITY (subtable, hard_pri, 2, sizeof *subtable,
+ &cls->subtables) {
+ struct cls_conjunction_set *conj_set;
+
+ /* Skip subtables with no match, or where the match is lower-priority
+ * than some certain match we've already found. */
+ match = find_match_wc(subtable, version, flow, trie_ctx, cls->n_tries,
+ wc);
+ if (!match || match->priority <= hard_pri) {
+ continue;
+ }
+
+ conj_set = ovsrcu_get(struct cls_conjunction_set *, &match->conj_set);
+ if (!conj_set) {
+ /* 'match' isn't part of a conjunctive match. It's the best
+ * certain match we've got so far, since we know that it's
+ * higher-priority than hard_pri.
+ *
+ * (There might be a higher-priority conjunctive match. We can't
+ * tell yet.) */
+ hard = match;
+ hard_pri = hard->priority;
+ } else if (allow_conjunctive_matches) {
+ /* 'match' is part of a conjunctive match. Add it to the list. */
+ if (OVS_UNLIKELY(n_soft >= allocated_soft)) {
+ struct cls_conjunction_set **old_soft = soft;
+
+ allocated_soft *= 2;
+ soft = xmalloc(allocated_soft * sizeof *soft);
+ memcpy(soft, old_soft, n_soft * sizeof *soft);
+ if (old_soft != soft_stub) {
+ free(old_soft);
+ }
+ }
+ soft[n_soft++] = conj_set;
+
+ /* Keep track of the highest-priority soft match. */
+ if (soft_pri < match->priority) {
+ soft_pri = match->priority;
+ }
}
}
- return NULL;
-}
+ /* In the common case, at this point we have no soft matches and we can
+ * return immediately. (We do the same thing if we have potential soft
+ * matches but none of them are higher-priority than our hard match.) */
+ if (hard_pri >= soft_pri) {
+ if (soft != soft_stub) {
+ free(soft);
+ }
+ return hard ? hard->cls_rule : NULL;
+ }
-/* Finds and returns the highest-priority rule in 'cls' that matches
- * 'miniflow'. Returns a null pointer if no rules in 'cls' match 'flow'.
- * If multiple rules of equal priority match 'flow', returns one arbitrarily.
- *
- * This function is optimized for the userspace datapath, which only ever has
- * one priority value for it's flows!
- */
-struct cls_rule *classifier_lookup_miniflow_first(const struct classifier *cls_,
- const struct miniflow *flow)
-{
- struct cls_classifier *cls = cls_->cls;
- struct cls_subtable *subtable;
+ /* At this point, we have some soft matches. We might also have a hard
+ * match; if so, its priority is lower than the highest-priority soft
+ * match. */
- PVECTOR_FOR_EACH (subtable, &cls->subtables) {
- struct cls_match *rule;
+ /* Soft match loop.
+ *
+ * Check whether soft matches are real matches. */
+ for (;;) {
+ /* Delete soft matches that are null. This only happens in second and
+ * subsequent iterations of the soft match loop, when we drop back from
+ * a high-priority soft match to a lower-priority one.
+ *
+ * Also, delete soft matches whose priority is less than or equal to
+ * the hard match's priority. In the first iteration of the soft
+ * match, these can be in 'soft' because the earlier main loop found
+ * the soft match before the hard match. In second and later iteration
+ * of the soft match loop, these can be in 'soft' because we dropped
+ * back from a high-priority soft match to a lower-priority soft match.
+ *
+ * It is tempting to delete soft matches that cannot be satisfied
+ * because there are fewer soft matches than required to satisfy any of
+ * their conjunctions, but we cannot do that because there might be
+ * lower priority soft or hard matches with otherwise identical
+ * matches. (We could special case those here, but there's no
+ * need--we'll do so at the bottom of the soft match loop anyway and
+ * this duplicates less code.)
+ *
+ * It's also tempting to break out of the soft match loop if 'n_soft ==
+ * 1' but that would also miss lower-priority hard matches. We could
+ * special case that also but again there's no need. */
+ for (int i = 0; i < n_soft; ) {
+ if (!soft[i] || soft[i]->priority <= hard_pri) {
+ soft[i] = soft[--n_soft];
+ } else {
+ i++;
+ }
+ }
+ if (!n_soft) {
+ break;
+ }
- rule = find_match_miniflow(subtable, flow,
- miniflow_hash_in_minimask(flow,
- &subtable->mask,
- 0));
- if (rule) {
- return rule->cls_rule;
+ /* Find the highest priority among the soft matches. (We know this
+ * must be higher than the hard match's priority; otherwise we would
+ * have deleted all of the soft matches in the previous loop.) Count
+ * the number of soft matches that have that priority. */
+ soft_pri = INT_MIN;
+ int n_soft_pri = 0;
+ for (int i = 0; i < n_soft; i++) {
+ if (soft[i]->priority > soft_pri) {
+ soft_pri = soft[i]->priority;
+ n_soft_pri = 1;
+ } else if (soft[i]->priority == soft_pri) {
+ n_soft_pri++;
+ }
+ }
+ ovs_assert(soft_pri > hard_pri);
+
+ /* Look for a real match among the highest-priority soft matches.
+ *
+ * It's unusual to have many conjunctive matches, so we use stubs to
+ * avoid calling malloc() in the common case. An hmap has a built-in
+ * stub for up to 2 hmap_nodes; possibly, we would benefit a variant
+ * with a bigger stub. */
+ struct conjunctive_match cm_stubs[16];
+ struct hmap matches;
+
+ hmap_init(&matches);
+ for (int i = 0; i < n_soft; i++) {
+ uint32_t id;
+
+ if (soft[i]->priority == soft_pri
+ && find_conjunctive_match(soft[i], n_soft_pri, &matches,
+ cm_stubs, ARRAY_SIZE(cm_stubs),
+ &id)) {
+ uint32_t saved_conj_id = flow->conj_id;
+ const struct cls_rule *rule;
+
+ flow->conj_id = id;
+ rule = classifier_lookup__(cls, version, flow, wc, false);
+ flow->conj_id = saved_conj_id;
+
+ if (rule) {
+ free_conjunctive_matches(&matches,
+ cm_stubs, ARRAY_SIZE(cm_stubs));
+ if (soft != soft_stub) {
+ free(soft);
+ }
+ return rule;
+ }
+ }
+ }
+ free_conjunctive_matches(&matches, cm_stubs, ARRAY_SIZE(cm_stubs));
+
+ /* There's no real match among the highest-priority soft matches.
+ * However, if any of those soft matches has a lower-priority but
+ * otherwise identical flow match, then we need to consider those for
+ * soft or hard matches.
+ *
+ * The next iteration of the soft match loop will delete any null
+ * pointers we put into 'soft' (and some others too). */
+ for (int i = 0; i < n_soft; i++) {
+ if (soft[i]->priority != soft_pri) {
+ continue;
+ }
+
+ /* Find next-lower-priority flow with identical flow match. */
+ match = next_visible_rule_in_list(soft[i]->match, version);
+ if (match) {
+ soft[i] = ovsrcu_get(struct cls_conjunction_set *,
+ &match->conj_set);
+ if (!soft[i]) {
+ /* The flow is a hard match; don't treat as a soft
+ * match. */
+ if (match->priority > hard_pri) {
+ hard = match;
+ hard_pri = hard->priority;
+ }
+ }
+ } else {
+ /* No such lower-priority flow (probably the common case). */
+ soft[i] = NULL;
+ }
}
}
- return NULL;
+ if (soft != soft_stub) {
+ free(soft);
+ }
+ return hard ? hard->cls_rule : NULL;
+}
+
+/* Finds and returns the highest-priority rule in 'cls' that matches 'flow' and
+ * that is visible in 'version'. Returns a null pointer if no rules in 'cls'
+ * match 'flow'. If multiple rules of equal priority match 'flow', returns one
+ * arbitrarily.
+ *
+ * If a rule is found and 'wc' is non-null, bitwise-OR's 'wc' with the
+ * set of bits that were significant in the lookup. At some point
+ * earlier, 'wc' should have been initialized (e.g., by
+ * flow_wildcards_init_catchall()).
+ *
+ * 'flow' is non-const to allow for temporary modifications during the lookup.
+ * Any changes are restored before returning. */
+const struct cls_rule *
+classifier_lookup(const struct classifier *cls, cls_version_t version,
+ struct flow *flow, struct flow_wildcards *wc)
+{
+ return classifier_lookup__(cls, version, flow, wc, true);
}
/* Finds and returns a rule in 'cls' with exactly the same priority and
- * matching criteria as 'target'. Returns a null pointer if 'cls' doesn't
+ * matching criteria as 'target', and that is visible in 'version'.
+ * Only one such rule may ever exist. Returns a null pointer if 'cls' doesn't
* contain an exact match. */
-struct cls_rule *
-classifier_find_rule_exactly(const struct classifier *cls_,
- const struct cls_rule *target)
+const struct cls_rule *
+classifier_find_rule_exactly(const struct classifier *cls,
+ const struct cls_rule *target,
+ cls_version_t version)
{
- struct cls_classifier *cls = cls_->cls;
- struct cls_match *head, *rule;
- struct cls_subtable *subtable;
+ const struct cls_match *head, *rule;
+ const struct cls_subtable *subtable;
- subtable = find_subtable(cls, &target->match.mask);
+ subtable = find_subtable(cls, target->match.mask);
if (!subtable) {
return NULL;
}
- /* Skip if there is no hope. */
- if (target->priority > subtable->max_priority) {
+ head = find_equal(subtable, target->match.flow,
+ miniflow_hash_in_minimask(target->match.flow,
+ target->match.mask, 0));
+ if (!head) {
return NULL;
}
-
- head = find_equal(subtable, &target->match.flow,
- miniflow_hash_in_minimask(&target->match.flow,
- &target->match.mask, 0));
- FOR_EACH_RULE_IN_LIST (rule, head) {
- if (target->priority >= rule->priority) {
- return target->priority == rule->priority ? rule->cls_rule : NULL;
+ CLS_MATCH_FOR_EACH (rule, head) {
+ if (rule->priority < target->priority) {
+ break; /* Not found. */
+ }
+ if (rule->priority == target->priority
+ && cls_match_visible_in_version(rule, version)) {
+ return rule->cls_rule;
}
}
return NULL;
}
/* Finds and returns a rule in 'cls' with priority 'priority' and exactly the
- * same matching criteria as 'target'. Returns a null pointer if 'cls' doesn't
- * contain an exact match. */
-struct cls_rule *
+ * same matching criteria as 'target', and that is visible in 'version'.
+ * Returns a null pointer if 'cls' doesn't contain an exact match visible in
+ * 'version'. */
+const struct cls_rule *
classifier_find_match_exactly(const struct classifier *cls,
- const struct match *target,
- unsigned int priority)
+ const struct match *target, int priority,
+ cls_version_t version)
{
- struct cls_rule *retval;
+ const struct cls_rule *retval;
struct cls_rule cr;
cls_rule_init(&cr, target, priority);
- retval = classifier_find_rule_exactly(cls, &cr);
+ retval = classifier_find_rule_exactly(cls, &cr, version);
cls_rule_destroy(&cr);
return retval;
}
-/* Checks if 'target' would overlap any other rule in 'cls'. Two rules are
- * considered to overlap if both rules have the same priority and a packet
- * could match both. */
+/* Checks if 'target' would overlap any other rule in 'cls' in 'version'. Two
+ * rules are considered to overlap if both rules have the same priority and a
+ * packet could match both, and if both rules are visible in the same version.
+ *
+ * A trivial example of overlapping rules is two rules matching disjoint sets
+ * of fields. E.g., if one rule matches only on port number, while another only
+ * on dl_type, any packet from that specific port and with that specific
+ * dl_type could match both, if the rules also have the same priority. */
bool
-classifier_rule_overlaps(const struct classifier *cls_,
- const struct cls_rule *target)
+classifier_rule_overlaps(const struct classifier *cls,
+ const struct cls_rule *target, cls_version_t version)
{
- struct cls_classifier *cls = cls_->cls;
struct cls_subtable *subtable;
- int64_t stop_at_priority = (int64_t)target->priority - 1;
/* Iterate subtables in the descending max priority order. */
- PVECTOR_FOR_EACH_PRIORITY (subtable, stop_at_priority, 2,
+ PVECTOR_FOR_EACH_PRIORITY (subtable, target->priority - 1, 2,
sizeof(struct cls_subtable), &cls->subtables) {
- uint32_t storage[FLOW_U32S];
- struct minimask mask;
- struct cls_match *head;
-
- minimask_combine(&mask, &target->match.mask, &subtable->mask, storage);
- HMAP_FOR_EACH (head, hmap_node, &subtable->rules) {
- struct cls_match *rule;
-
- FOR_EACH_RULE_IN_LIST (rule, head) {
- if (rule->priority < target->priority) {
- break; /* Rules in descending priority order. */
- }
- if (rule->priority == target->priority
- && miniflow_equal_in_minimask(&target->match.flow,
- &rule->flow, &mask)) {
- return true;
- }
+ struct {
+ struct minimask mask;
+ uint64_t storage[FLOW_U64S];
+ } m;
+ const struct cls_rule *rule;
+
+ minimask_combine(&m.mask, target->match.mask, &subtable->mask,
+ m.storage);
+
+ RCULIST_FOR_EACH (rule, node, &subtable->rules_list) {
+ if (rule->priority == target->priority
+ && miniflow_equal_in_minimask(target->match.flow,
+ rule->match.flow, &m.mask)
+ && cls_match_visible_in_version(rule->cls_match, version)) {
+ return true;
}
}
}
-
return false;
}
cls_rule_is_loose_match(const struct cls_rule *rule,
const struct minimatch *criteria)
{
- return (!minimask_has_extra(&rule->match.mask, &criteria->mask)
- && miniflow_equal_in_minimask(&rule->match.flow, &criteria->flow,
- &criteria->mask));
+ return (!minimask_has_extra(rule->match.mask, criteria->mask)
+ && miniflow_equal_in_minimask(rule->match.flow, criteria->flow,
+ criteria->mask));
}
\f
/* Iteration. */
static bool
-rule_matches(const struct cls_match *rule, const struct cls_rule *target)
+rule_matches(const struct cls_rule *rule, const struct cls_rule *target,
+ cls_version_t version)
{
- return (!target
- || miniflow_equal_in_minimask(&rule->flow,
- &target->match.flow,
- &target->match.mask));
+ /* Rule may only match a target if it is visible in target's version. */
+ return cls_match_visible_in_version(rule->cls_match, version)
+ && (!target || miniflow_equal_in_minimask(rule->match.flow,
+ target->match.flow,
+ target->match.mask));
}
-static struct cls_match *
+static const struct cls_rule *
search_subtable(const struct cls_subtable *subtable,
- const struct cls_rule *target)
+ struct cls_cursor *cursor)
{
- if (!target || !minimask_has_extra(&subtable->mask, &target->match.mask)) {
- struct cls_match *rule;
+ if (!cursor->target
+ || !minimask_has_extra(&subtable->mask, cursor->target->match.mask)) {
+ const struct cls_rule *rule;
- HMAP_FOR_EACH (rule, hmap_node, &subtable->rules) {
- if (rule_matches(rule, target)) {
+ RCULIST_FOR_EACH (rule, node, &subtable->rules_list) {
+ if (rule_matches(rule, cursor->target, cursor->version)) {
return rule;
}
}
return NULL;
}
-/* Initializes 'cursor' for iterating through rules in 'cls':
+/* Initializes 'cursor' for iterating through rules in 'cls', and returns the
+ * cursor.
*
- * - If 'target' is null, the cursor will visit every rule in 'cls'.
+ * - If 'target' is null, or if the 'target' is a catchall target, the
+ * cursor will visit every rule in 'cls' that is visible in 'version'.
*
* - If 'target' is nonnull, the cursor will visit each 'rule' in 'cls'
- * such that cls_rule_is_loose_match(rule, target) returns true.
+ * such that cls_rule_is_loose_match(rule, target) returns true and that
+ * the rule is visible in 'version'.
*
* Ignores target->priority. */
-void
-cls_cursor_init(struct cls_cursor *cursor, const struct classifier *cls,
- const struct cls_rule *target)
-{
- cursor->cls = cls->cls;
- cursor->target = target && !cls_rule_is_catchall(target) ? target : NULL;
-}
-
-/* Returns the first matching cls_rule in 'cursor''s iteration, or a null
- * pointer if there are no matches. */
-struct cls_rule *
-cls_cursor_first(struct cls_cursor *cursor)
+struct cls_cursor
+cls_cursor_start(const struct classifier *cls, const struct cls_rule *target,
+ cls_version_t version)
{
+ struct cls_cursor cursor;
struct cls_subtable *subtable;
- HMAP_FOR_EACH (subtable, hmap_node, &cursor->cls->subtables_map) {
- struct cls_match *rule = search_subtable(subtable, cursor->target);
+ cursor.cls = cls;
+ cursor.target = target && !cls_rule_is_catchall(target) ? target : NULL;
+ cursor.version = version;
+ cursor.rule = NULL;
+
+ /* Find first rule. */
+ PVECTOR_CURSOR_FOR_EACH (subtable, &cursor.subtables,
+ &cursor.cls->subtables) {
+ const struct cls_rule *rule = search_subtable(subtable, &cursor);
+
if (rule) {
- cursor->subtable = subtable;
- return rule->cls_rule;
+ cursor.subtable = subtable;
+ cursor.rule = rule;
+ break;
}
}
- return NULL;
+ return cursor;
}
-/* Returns the next matching cls_rule in 'cursor''s iteration, or a null
- * pointer if there are no more matches. */
-struct cls_rule *
-cls_cursor_next(struct cls_cursor *cursor, const struct cls_rule *rule_)
+static const struct cls_rule *
+cls_cursor_next(struct cls_cursor *cursor)
{
- struct cls_match *rule = CONST_CAST(struct cls_match *, rule_->cls_match);
+ const struct cls_rule *rule;
const struct cls_subtable *subtable;
- struct cls_match *next;
-
- next = next_rule_in_list__(rule);
- if (next->priority < rule->priority) {
- return next->cls_rule;
- }
- /* 'next' is the head of the list, that is, the rule that is included in
- * the subtable's hmap. (This is important when the classifier contains
- * rules that differ only in priority.) */
- rule = next;
- HMAP_FOR_EACH_CONTINUE (rule, hmap_node, &cursor->subtable->rules) {
- if (rule_matches(rule, cursor->target)) {
- return rule->cls_rule;
+ rule = cursor->rule;
+ subtable = cursor->subtable;
+ RCULIST_FOR_EACH_CONTINUE (rule, node, &subtable->rules_list) {
+ if (rule_matches(rule, cursor->target, cursor->version)) {
+ return rule;
}
}
- subtable = cursor->subtable;
- HMAP_FOR_EACH_CONTINUE (subtable, hmap_node, &cursor->cls->subtables_map) {
- rule = search_subtable(subtable, cursor->target);
+ PVECTOR_CURSOR_FOR_EACH_CONTINUE (subtable, &cursor->subtables) {
+ rule = search_subtable(subtable, cursor);
if (rule) {
cursor->subtable = subtable;
- return rule->cls_rule;
+ return rule;
}
}
return NULL;
}
+
+/* Sets 'cursor->rule' to the next matching cls_rule in 'cursor''s iteration,
+ * or to null if all matching rules have been visited. */
+void
+cls_cursor_advance(struct cls_cursor *cursor)
+{
+ cursor->rule = cls_cursor_next(cursor);
+}
\f
static struct cls_subtable *
-find_subtable(const struct cls_classifier *cls, const struct minimask *mask)
+find_subtable(const struct classifier *cls, const struct minimask *mask)
{
struct cls_subtable *subtable;
- HMAP_FOR_EACH_IN_BUCKET (subtable, hmap_node, minimask_hash(mask, 0),
+ CMAP_FOR_EACH_WITH_HASH (subtable, cmap_node, minimask_hash(mask, 0),
&cls->subtables_map) {
if (minimask_equal(mask, &subtable->mask)) {
return subtable;
return NULL;
}
+/* Initializes 'map' with a subset of 'miniflow''s maps that includes only the
+ * portions with u64-offset 'i' such that 'start' <= i < 'end'. Does not copy
+ * any data from 'miniflow' to 'map'. */
+static struct flowmap
+miniflow_get_map_in_range(const struct miniflow *miniflow, uint8_t start,
+ uint8_t end)
+{
+ struct flowmap map;
+ size_t ofs = 0;
+
+ map = miniflow->map;
+
+ /* Clear the bits before 'start'. */
+ while (start >= MAP_T_BITS) {
+ start -= MAP_T_BITS;
+ ofs += MAP_T_BITS;
+ map.bits[start / MAP_T_BITS] = 0;
+ }
+ if (start > 0) {
+ flowmap_clear(&map, ofs, start);
+ }
+
+ /* Clear the bits starting at 'end'. */
+ if (end < FLOW_U64S) {
+ /* flowmap_clear() can handle at most MAP_T_BITS at a time. */
+ ovs_assert(FLOW_U64S - end <= MAP_T_BITS);
+ flowmap_clear(&map, end, FLOW_U64S - end);
+ }
+ return map;
+}
+
+/* The new subtable will be visible to the readers only after this. */
static struct cls_subtable *
-insert_subtable(struct cls_classifier *cls, const struct minimask *mask)
+insert_subtable(struct classifier *cls, const struct minimask *mask)
{
uint32_t hash = minimask_hash(mask, 0);
struct cls_subtable *subtable;
int i, index = 0;
- struct flow_wildcards old, new;
+ struct flowmap stage_map;
uint8_t prev;
- int count = count_1bits(mask->masks.map);
+ size_t count = miniflow_n_values(&mask->masks);
- subtable = xzalloc(sizeof *subtable - sizeof mask->masks.inline_values
- + MINIFLOW_VALUES_SIZE(count));
- hmap_init(&subtable->rules);
- miniflow_clone_inline(&subtable->mask.masks, &mask->masks, count);
+ subtable = xzalloc(sizeof *subtable + MINIFLOW_VALUES_SIZE(count));
+ cmap_init(&subtable->rules);
+ miniflow_clone(CONST_CAST(struct miniflow *, &subtable->mask.masks),
+ &mask->masks, count);
/* Init indices for segmented lookup, if any. */
- flow_wildcards_init_catchall(&new);
- old = new;
prev = 0;
for (i = 0; i < cls->n_flow_segments; i++) {
- flow_wildcards_fold_minimask_range(&new, mask, prev,
- cls->flow_segments[i]);
+ stage_map = miniflow_get_map_in_range(&mask->masks, prev,
+ cls->flow_segments[i]);
/* Add an index if it adds mask bits. */
- if (!flow_wildcards_equal(&new, &old)) {
- hindex_init(&subtable->indices[index]);
- subtable->index_ofs[index] = cls->flow_segments[i];
+ if (!flowmap_is_empty(stage_map)) {
+ cmap_init(&subtable->indices[index]);
+ *CONST_CAST(struct flowmap *, &subtable->index_maps[index])
+ = stage_map;
index++;
- old = new;
}
prev = cls->flow_segments[i];
}
- /* Check if the rest of the subtable's mask adds any bits,
+ /* Map for the final stage. */
+ *CONST_CAST(struct flowmap *, &subtable->index_maps[index])
+ = miniflow_get_map_in_range(&mask->masks, prev, FLOW_U64S);
+ /* Check if the final stage adds any bits,
* and remove the last index if it doesn't. */
if (index > 0) {
- flow_wildcards_fold_minimask_range(&new, mask, prev, FLOW_U32S);
- if (flow_wildcards_equal(&new, &old)) {
+ if (flowmap_equal(subtable->index_maps[index],
+ subtable->index_maps[index - 1])) {
--index;
- subtable->index_ofs[index] = 0;
- hindex_destroy(&subtable->indices[index]);
+ cmap_destroy(&subtable->indices[index]);
}
}
- subtable->n_indices = index;
-
- subtable->tag = (minimask_get_metadata_mask(mask) == OVS_BE64_MAX
- ? tag_create_deterministic(hash)
- : TAG_ALL);
+ *CONST_CAST(uint8_t *, &subtable->n_indices) = index;
for (i = 0; i < cls->n_tries; i++) {
subtable->trie_plen[i] = minimask_get_prefix_len(mask,
}
/* Ports trie. */
- subtable->ports_trie = NULL;
- subtable->ports_mask_len
+ ovsrcu_set_hidden(&subtable->ports_trie, NULL);
+ *CONST_CAST(int *, &subtable->ports_mask_len)
= 32 - ctz32(ntohl(MINIFLOW_GET_BE32(&mask->masks, tp_src)));
- hmap_insert(&cls->subtables_map, &subtable->hmap_node, hash);
+ /* List of rules. */
+ rculist_init(&subtable->rules_list);
+
+ cmap_insert(&cls->subtables_map, &subtable->cmap_node, hash);
return subtable;
}
+/* RCU readers may still access the subtable before it is actually freed. */
static void
-destroy_subtable(struct cls_classifier *cls, struct cls_subtable *subtable)
+destroy_subtable(struct classifier *cls, struct cls_subtable *subtable)
{
int i;
pvector_remove(&cls->subtables, subtable);
- trie_destroy(subtable->ports_trie);
+ cmap_remove(&cls->subtables_map, &subtable->cmap_node,
+ minimask_hash(&subtable->mask, 0));
+
+ ovs_assert(ovsrcu_get_protected(struct trie_node *, &subtable->ports_trie)
+ == NULL);
+ ovs_assert(cmap_is_empty(&subtable->rules));
+ ovs_assert(rculist_is_empty(&subtable->rules_list));
for (i = 0; i < subtable->n_indices; i++) {
- hindex_destroy(&subtable->indices[i]);
+ cmap_destroy(&subtable->indices[i]);
}
- hmap_remove(&cls->subtables_map, &subtable->hmap_node);
- minimask_destroy(&subtable->mask);
- hmap_destroy(&subtable->rules);
+ cmap_destroy(&subtable->rules);
ovsrcu_postpone(free, subtable);
}
-struct range {
- uint8_t start;
- uint8_t end;
-};
+static unsigned int be_get_bit_at(const ovs_be32 value[], unsigned int ofs);
/* Return 'true' if can skip rest of the subtable based on the prefix trie
* lookup results. */
static inline bool
check_tries(struct trie_ctx trie_ctx[CLS_MAX_TRIES], unsigned int n_tries,
const unsigned int field_plen[CLS_MAX_TRIES],
- const struct range ofs, const struct flow *flow,
+ const struct flowmap range_map, const struct flow *flow,
struct flow_wildcards *wc)
{
int j;
* fields using the prefix tries. The trie checks are done only as
* needed to avoid folding in additional bits to the wildcards mask. */
for (j = 0; j < n_tries; j++) {
- /* Is the trie field relevant for this subtable? */
- if (field_plen[j]) {
+ /* Is the trie field relevant for this subtable, and
+ is the trie field within the current range of fields? */
+ if (field_plen[j] &&
+ flowmap_is_set(&range_map, trie_ctx[j].be32ofs / 2)) {
struct trie_ctx *ctx = &trie_ctx[j];
- uint8_t be32ofs = ctx->be32ofs;
-
- /* Is the trie field within the current range of fields? */
- if (be32ofs >= ofs.start && be32ofs < ofs.end) {
- /* On-demand trie lookup. */
- if (!ctx->lookup_done) {
- ctx->match_plen = trie_lookup(ctx->trie, flow,
- &ctx->maskbits);
- ctx->lookup_done = true;
+
+ /* On-demand trie lookup. */
+ if (!ctx->lookup_done) {
+ memset(&ctx->match_plens, 0, sizeof ctx->match_plens);
+ ctx->maskbits = trie_lookup(ctx->trie, flow, &ctx->match_plens);
+ ctx->lookup_done = true;
+ }
+ /* Possible to skip the rest of the subtable if subtable's
+ * prefix on the field is not included in the lookup result. */
+ if (!be_get_bit_at(&ctx->match_plens.be32, field_plen[j] - 1)) {
+ /* We want the trie lookup to never result in unwildcarding
+ * any bits that would not be unwildcarded otherwise.
+ * Since the trie is shared by the whole classifier, it is
+ * possible that the 'maskbits' contain bits that are
+ * irrelevant for the partition relevant for the current
+ * packet. Hence the checks below. */
+
+ /* Check that the trie result will not unwildcard more bits
+ * than this subtable would otherwise. */
+ if (ctx->maskbits <= field_plen[j]) {
+ /* Unwildcard the bits and skip the rest. */
+ mask_set_prefix_bits(wc, ctx->be32ofs, ctx->maskbits);
+ /* Note: Prerequisite already unwildcarded, as the only
+ * prerequisite of the supported trie lookup fields is
+ * the ethertype, which is always unwildcarded. */
+ return true;
}
- /* Possible to skip the rest of the subtable if subtable's
- * prefix on the field is longer than what is known to match
- * based on the trie lookup. */
- if (field_plen[j] > ctx->match_plen) {
- /* RFC: We want the trie lookup to never result in
- * unwildcarding any bits that would not be unwildcarded
- * otherwise. Since the trie is shared by the whole
- * classifier, it is possible that the 'maskbits' contain
- * bits that are irrelevant for the partition of the
- * classifier relevant for the current flow. */
-
- /* Can skip if the field is already unwildcarded. */
- if (mask_prefix_bits_set(wc, be32ofs, ctx->maskbits)) {
- return true;
- }
- /* Check that the trie result will not unwildcard more bits
- * than this stage will. */
- if (ctx->maskbits <= field_plen[j]) {
- /* Unwildcard the bits and skip the rest. */
- mask_set_prefix_bits(wc, be32ofs, ctx->maskbits);
- /* Note: Prerequisite already unwildcarded, as the only
- * prerequisite of the supported trie lookup fields is
- * the ethertype, which is currently always
- * unwildcarded.
- */
- return true;
- }
+ /* Can skip if the field is already unwildcarded. */
+ if (mask_prefix_bits_set(wc, ctx->be32ofs, ctx->maskbits)) {
+ return true;
}
}
}
static inline bool
miniflow_and_mask_matches_flow(const struct miniflow *flow,
const struct minimask *mask,
- const struct flow *target,
- struct flow_wildcards *wc)
-{
- const uint32_t *flowp = miniflow_get_u32_values(flow);
- const uint32_t *maskp = miniflow_get_u32_values(&mask->masks);
- uint32_t idx;
-
- MAP_FOR_EACH_INDEX(idx, mask->masks.map) {
- uint32_t diff = (*flowp++ ^ flow_u32_value(target, idx)) & *maskp++;
-
- if (diff) {
- /* Only unwildcard if none of the differing bits is already
- * exact-matched. */
- if (wc && !(flow_u32_value(&wc->masks, idx) & diff)) {
- /* Keep one bit of the difference. */
- *flow_u32_lvalue(&wc->masks, idx) |= rightmost_1bit(diff);
+ const struct flow *target)
+{
+ const uint64_t *flowp = miniflow_get_values(flow);
+ const uint64_t *maskp = miniflow_get_values(&mask->masks);
+ const uint64_t *target_u64 = (const uint64_t *)target;
+ map_t map;
+
+ FLOWMAP_FOR_EACH_MAP (map, mask->masks.map) {
+ size_t idx;
+
+ MAP_FOR_EACH_INDEX (idx, map) {
+ if ((*flowp++ ^ target_u64[idx]) & *maskp++) {
+ return false;
}
- return false;
}
+ target_u64 += MAP_T_BITS;
}
-
return true;
}
-static inline struct cls_match *
-find_match(const struct cls_subtable *subtable, const struct flow *flow,
- uint32_t hash)
+static inline const struct cls_match *
+find_match(const struct cls_subtable *subtable, cls_version_t version,
+ const struct flow *flow, uint32_t hash)
{
- struct cls_match *rule;
+ const struct cls_match *head, *rule;
- HMAP_FOR_EACH_WITH_HASH (rule, hmap_node, hash, &subtable->rules) {
- if (miniflow_and_mask_matches_flow(&rule->flow, &subtable->mask,
- flow, NULL)) {
- return rule;
+ CMAP_FOR_EACH_WITH_HASH (head, cmap_node, hash, &subtable->rules) {
+ if (OVS_LIKELY(miniflow_and_mask_matches_flow(&head->flow,
+ &subtable->mask,
+ flow))) {
+ /* Return highest priority rule that is visible. */
+ CLS_MATCH_FOR_EACH (rule, head) {
+ if (OVS_LIKELY(cls_match_visible_in_version(rule, version))) {
+ return rule;
+ }
+ }
}
}
return NULL;
}
-static struct cls_match *
-find_match_wc(const struct cls_subtable *subtable, const struct flow *flow,
- struct trie_ctx trie_ctx[CLS_MAX_TRIES], unsigned int n_tries,
- struct flow_wildcards *wc)
-{
- uint32_t basis = 0, hash;
- struct cls_match *rule;
- int i;
- struct range ofs;
+/* Returns true if 'target' satisifies 'flow'/'mask', that is, if each bit
+ * for which 'flow', for which 'mask' has a bit set, specifies a particular
+ * value has the correct value in 'target'.
+ *
+ * This function is equivalent to miniflow_and_mask_matches_flow() but this
+ * version fills in the mask bits in 'wc'. */
+static inline bool
+miniflow_and_mask_matches_flow_wc(const struct miniflow *flow,
+ const struct minimask *mask,
+ const struct flow *target,
+ struct flow_wildcards *wc)
+{
+ const uint64_t *flowp = miniflow_get_values(flow);
+ const uint64_t *maskp = miniflow_get_values(&mask->masks);
+ const uint64_t *target_u64 = (const uint64_t *)target;
+ uint64_t *wc_u64 = (uint64_t *)&wc->masks;
+ uint64_t diff;
+ size_t idx;
+ map_t map;
+
+ FLOWMAP_FOR_EACH_MAP (map, mask->masks.map) {
+ MAP_FOR_EACH_INDEX(idx, map) {
+ uint64_t msk = *maskp++;
+
+ diff = (*flowp++ ^ target_u64[idx]) & msk;
+ if (diff) {
+ goto out;
+ }
+ /* Fill in the bits that were looked at. */
+ wc_u64[idx] |= msk;
+ }
+ target_u64 += MAP_T_BITS;
+ wc_u64 += MAP_T_BITS;
+ }
+ return true;
+
+out:
+ /* Only unwildcard if none of the differing bits is already
+ * exact-matched. */
+ if (!(wc_u64[idx] & diff)) {
+ /* Keep one bit of the difference. The selected bit may be
+ * different in big-endian v.s. little-endian systems. */
+ wc_u64[idx] |= rightmost_1bit(diff);
+ }
+ return false;
+}
+
+static const struct cls_match *
+find_match_wc(const struct cls_subtable *subtable, cls_version_t version,
+ const struct flow *flow, struct trie_ctx trie_ctx[CLS_MAX_TRIES],
+ unsigned int n_tries, struct flow_wildcards *wc)
+{
if (OVS_UNLIKELY(!wc)) {
- return find_match(subtable, flow,
+ return find_match(subtable, version, flow,
flow_hash_in_minimask(flow, &subtable->mask, 0));
}
- ofs.start = 0;
+ uint32_t basis = 0, hash;
+ const struct cls_match *rule = NULL;
+ struct flowmap stages_map = FLOWMAP_EMPTY_INITIALIZER;
+ unsigned int mask_offset = 0;
+ int i;
+
/* Try to finish early by checking fields in segments. */
for (i = 0; i < subtable->n_indices; i++) {
- struct hindex_node *inode;
- ofs.end = subtable->index_ofs[i];
+ const struct cmap_node *inode;
- if (check_tries(trie_ctx, n_tries, subtable->trie_plen, ofs, flow,
- wc)) {
- goto range_out;
+ if (check_tries(trie_ctx, n_tries, subtable->trie_plen,
+ subtable->index_maps[i], flow, wc)) {
+ /* 'wc' bits for the trie field set, now unwildcard the preceding
+ * bits used so far. */
+ goto no_match;
}
- hash = flow_hash_in_minimask_range(flow, &subtable->mask, ofs.start,
- ofs.end, &basis);
- ofs.start = ofs.end;
- inode = hindex_node_with_hash(&subtable->indices[i], hash);
+
+ /* Accumulate the map used so far. */
+ stages_map = flowmap_or(stages_map, subtable->index_maps[i]);
+
+ hash = flow_hash_in_minimask_range(flow, &subtable->mask,
+ subtable->index_maps[i],
+ &mask_offset, &basis);
+
+ inode = cmap_find(&subtable->indices[i], hash);
if (!inode) {
- /* No match, can stop immediately, but must fold in the mask
- * covered so far. */
- goto range_out;
+ goto no_match;
}
/* If we have narrowed down to a single rule already, check whether
*
* (Rare) hash collisions may cause us to miss the opportunity for this
* optimization. */
- if (!inode->s) {
- ASSIGN_CONTAINER(rule, inode - i, index_nodes);
- if (miniflow_and_mask_matches_flow(&rule->flow, &subtable->mask,
- flow, wc)) {
- goto out;
+ if (!cmap_node_next(inode)) {
+ const struct cls_match *head;
+
+ ASSIGN_CONTAINER(head, inode - i, index_nodes);
+ if (miniflow_and_mask_matches_flow_wc(&head->flow, &subtable->mask,
+ flow, wc)) {
+ /* Return highest priority rule that is visible. */
+ CLS_MATCH_FOR_EACH (rule, head) {
+ if (OVS_LIKELY(cls_match_visible_in_version(rule,
+ version))) {
+ return rule;
+ }
+ }
}
- goto range_out;
+ return NULL;
}
}
- ofs.end = FLOW_U32S;
/* Trie check for the final range. */
- if (check_tries(trie_ctx, n_tries, subtable->trie_plen, ofs, flow, wc)) {
- goto range_out;
- }
- hash = flow_hash_in_minimask_range(flow, &subtable->mask, ofs.start,
- ofs.end, &basis);
- rule = find_match(subtable, flow, hash);
+ if (check_tries(trie_ctx, n_tries, subtable->trie_plen,
+ subtable->index_maps[i], flow, wc)) {
+ goto no_match;
+ }
+ hash = flow_hash_in_minimask_range(flow, &subtable->mask,
+ subtable->index_maps[i],
+ &mask_offset, &basis);
+ rule = find_match(subtable, version, flow, hash);
if (!rule && subtable->ports_mask_len) {
- /* Ports are always part of the final range, if any.
- * No match was found for the ports. Use the ports trie to figure out
- * which ports bits to unwildcard. */
+ /* The final stage had ports, but there was no match. Instead of
+ * unwildcarding all the ports bits, use the ports trie to figure out a
+ * smaller set of bits to unwildcard. */
unsigned int mbits;
- ovs_be32 value, mask;
+ ovs_be32 value, plens, mask;
mask = MINIFLOW_GET_BE32(&subtable->mask.masks, tp_src);
value = ((OVS_FORCE ovs_be32 *)flow)[TP_PORTS_OFS32] & mask;
- trie_lookup_value(subtable->ports_trie, &value, 32, &mbits);
+ mbits = trie_lookup_value(&subtable->ports_trie, &value, &plens, 32);
((OVS_FORCE ovs_be32 *)&wc->masks)[TP_PORTS_OFS32] |=
- mask & htonl(~0 << (32 - mbits));
+ mask & be32_prefix_mask(mbits);
- ofs.start = TP_PORTS_OFS32;
- goto range_out;
+ goto no_match;
}
-out:
+
/* Must unwildcard all the fields, as they were looked at. */
flow_wildcards_fold_minimask(wc, &subtable->mask);
return rule;
-range_out:
- /* Must unwildcard the fields looked up so far, if any. */
- if (ofs.start) {
- flow_wildcards_fold_minimask_range(wc, &subtable->mask, 0, ofs.start);
- }
+no_match:
+ /* Unwildcard the bits in stages so far, as they were used in determining
+ * there is no match. */
+ flow_wildcards_fold_minimask_in_map(wc, &subtable->mask, stages_map);
return NULL;
}
static struct cls_match *
-find_equal(struct cls_subtable *subtable, const struct miniflow *flow,
+find_equal(const struct cls_subtable *subtable, const struct miniflow *flow,
uint32_t hash)
{
struct cls_match *head;
- HMAP_FOR_EACH_WITH_HASH (head, hmap_node, hash, &subtable->rules) {
+ CMAP_FOR_EACH_WITH_HASH (head, cmap_node, hash, &subtable->rules) {
if (miniflow_equal(&head->flow, flow)) {
return head;
}
}
return NULL;
}
-
-static struct cls_match *
-insert_rule(struct cls_classifier *cls, struct cls_subtable *subtable,
- struct cls_rule *new)
-{
- struct cls_match *cls_match = cls_match_alloc(new);
- struct cls_match *head;
- struct cls_match *old = NULL;
- int i;
- uint32_t basis = 0, hash;
- uint8_t prev_be32ofs = 0;
-
- /* Add new node to segment indices. */
- for (i = 0; i < subtable->n_indices; i++) {
- hash = minimatch_hash_range(&new->match, prev_be32ofs,
- subtable->index_ofs[i], &basis);
- hindex_insert(&subtable->indices[i], &cls_match->index_nodes[i], hash);
- prev_be32ofs = subtable->index_ofs[i];
- }
- hash = minimatch_hash_range(&new->match, prev_be32ofs, FLOW_U32S, &basis);
- head = find_equal(subtable, &new->match.flow, hash);
- if (!head) {
- hmap_insert(&subtable->rules, &cls_match->hmap_node, hash);
- list_init(&cls_match->list);
- goto out;
- } else {
- /* Scan the list for the insertion point that will keep the list in
- * order of decreasing priority. */
- struct cls_match *rule;
-
- cls_match->hmap_node.hash = hash; /* Otherwise done by hmap_insert. */
-
- FOR_EACH_RULE_IN_LIST (rule, head) {
- if (cls_match->priority >= rule->priority) {
- if (rule == head) {
- /* 'cls_match' is the new highest-priority flow in the
- * list. */
- hmap_replace(&subtable->rules,
- &rule->hmap_node, &cls_match->hmap_node);
- }
-
- if (cls_match->priority == rule->priority) {
- list_replace(&cls_match->list, &rule->list);
- old = rule;
- } else {
- list_insert(&rule->list, &cls_match->list);
- }
- goto out;
- }
- }
-
- /* Insert 'new' at the end of the list. */
- list_push_back(&head->list, &cls_match->list);
- }
-
- out:
- if (!old) {
- subtable->n_rules++;
-
- /* Rule was added, not replaced. Update 'subtable's 'max_priority'
- * and 'max_count', if necessary. */
- if (subtable->n_rules == 1) {
- subtable->max_priority = cls_match->priority;
- subtable->max_count = 1;
- pvector_insert(&cls->subtables, subtable, cls_match->priority);
- } else if (subtable->max_priority == cls_match->priority) {
- ++subtable->max_count;
- } else if (cls_match->priority > subtable->max_priority) {
- subtable->max_priority = cls_match->priority;
- subtable->max_count = 1;
- pvector_change_priority(&cls->subtables, subtable, cls_match->priority);
- }
- } else {
- /* Remove old node from indices. */
- for (i = 0; i < subtable->n_indices; i++) {
- hindex_remove(&subtable->indices[i], &old->index_nodes[i]);
- }
- }
- return old;
-}
-
-static struct cls_match *
-next_rule_in_list__(struct cls_match *rule)
-{
- struct cls_match *next = OBJECT_CONTAINING(rule->list.next, next, list);
- return next;
-}
-
-static struct cls_match *
-next_rule_in_list(struct cls_match *rule)
-{
- struct cls_match *next = next_rule_in_list__(rule);
- return next->priority < rule->priority ? next : NULL;
-}
\f
/* A longest-prefix match tree. */
-struct trie_node {
- uint32_t prefix; /* Prefix bits for this node, MSB first. */
- uint8_t nbits; /* Never zero, except for the root node. */
- unsigned int n_rules; /* Number of rules that have this prefix. */
- struct trie_node *edges[2]; /* Both NULL if leaf. */
-};
-
-/* Max bits per node. Must fit in struct trie_node's 'prefix'.
- * Also tested with 16, 8, and 5 to stress the implementation. */
-#define TRIE_PREFIX_BITS 32
/* Return at least 'plen' bits of the 'prefix', starting at bit offset 'ofs'.
* Prefixes are in the network byte order, and the offset 0 corresponds to
return raw_get_prefix(pr, ofs, plen) & ~0u << (32 - plen);
}
-/* Return the number of equal bits in 'nbits' of 'prefix's MSBs and a 'value'
+/* Return the number of equal bits in 'n_bits' of 'prefix's MSBs and a 'value'
* starting at "MSB 0"-based offset 'ofs'. */
static unsigned int
-prefix_equal_bits(uint32_t prefix, unsigned int nbits, const ovs_be32 value[],
+prefix_equal_bits(uint32_t prefix, unsigned int n_bits, const ovs_be32 value[],
unsigned int ofs)
{
- uint64_t diff = prefix ^ raw_get_prefix(value, ofs, nbits);
+ uint64_t diff = prefix ^ raw_get_prefix(value, ofs, n_bits);
/* Set the bit after the relevant bits to limit the result. */
- return raw_clz64(diff << 32 | UINT64_C(1) << (63 - nbits));
+ return raw_clz64(diff << 32 | UINT64_C(1) << (63 - n_bits));
}
/* Return the number of equal bits in 'node' prefix and a 'prefix' of length
trie_prefix_equal_bits(const struct trie_node *node, const ovs_be32 prefix[],
unsigned int ofs, unsigned int plen)
{
- return prefix_equal_bits(node->prefix, MIN(node->nbits, plen - ofs),
+ return prefix_equal_bits(node->prefix, MIN(node->n_bits, plen - ofs),
prefix, ofs);
}
node->prefix = trie_get_prefix(prefix, ofs, plen);
if (plen <= TRIE_PREFIX_BITS) {
- node->nbits = plen;
- node->edges[0] = NULL;
- node->edges[1] = NULL;
+ node->n_bits = plen;
+ ovsrcu_set_hidden(&node->edges[0], NULL);
+ ovsrcu_set_hidden(&node->edges[1], NULL);
node->n_rules = n_rules;
} else { /* Need intermediate nodes. */
struct trie_node *subnode = trie_branch_create(prefix,
plen - TRIE_PREFIX_BITS,
n_rules);
int bit = get_bit_at(subnode->prefix, 0);
- node->nbits = TRIE_PREFIX_BITS;
- node->edges[bit] = subnode;
- node->edges[!bit] = NULL;
+ node->n_bits = TRIE_PREFIX_BITS;
+ ovsrcu_set_hidden(&node->edges[bit], subnode);
+ ovsrcu_set_hidden(&node->edges[!bit], NULL);
node->n_rules = 0;
}
return node;
}
static void
-trie_node_destroy(struct trie_node *node)
+trie_node_destroy(const struct trie_node *node)
+{
+ ovsrcu_postpone(free, CONST_CAST(struct trie_node *, node));
+}
+
+/* Copy a trie node for modification and postpone delete the old one. */
+static struct trie_node *
+trie_node_rcu_realloc(const struct trie_node *node)
{
- free(node);
+ struct trie_node *new_node = xmalloc(sizeof *node);
+
+ *new_node = *node;
+ trie_node_destroy(node);
+
+ return new_node;
}
static void
-trie_destroy(struct trie_node *node)
+trie_destroy(rcu_trie_ptr *trie)
{
+ struct trie_node *node = ovsrcu_get_protected(struct trie_node *, trie);
+
if (node) {
- trie_destroy(node->edges[0]);
- trie_destroy(node->edges[1]);
- free(node);
+ ovsrcu_set_hidden(trie, NULL);
+ trie_destroy(&node->edges[0]);
+ trie_destroy(&node->edges[1]);
+ trie_node_destroy(node);
}
}
static bool
trie_is_leaf(const struct trie_node *trie)
{
- return !trie->edges[0] && !trie->edges[1]; /* No children. */
+ /* No children? */
+ return !ovsrcu_get(struct trie_node *, &trie->edges[0])
+ && !ovsrcu_get(struct trie_node *, &trie->edges[1]);
}
static void
mask_set_prefix_bits(struct flow_wildcards *wc, uint8_t be32ofs,
- unsigned int nbits)
+ unsigned int n_bits)
{
ovs_be32 *mask = &((ovs_be32 *)&wc->masks)[be32ofs];
unsigned int i;
- for (i = 0; i < nbits / 32; i++) {
+ for (i = 0; i < n_bits / 32; i++) {
mask[i] = OVS_BE32_MAX;
}
- if (nbits % 32) {
- mask[i] |= htonl(~0u << (32 - nbits % 32));
+ if (n_bits % 32) {
+ mask[i] |= htonl(~0u << (32 - n_bits % 32));
}
}
static bool
mask_prefix_bits_set(const struct flow_wildcards *wc, uint8_t be32ofs,
- unsigned int nbits)
+ unsigned int n_bits)
{
ovs_be32 *mask = &((ovs_be32 *)&wc->masks)[be32ofs];
unsigned int i;
ovs_be32 zeroes = 0;
- for (i = 0; i < nbits / 32; i++) {
+ for (i = 0; i < n_bits / 32; i++) {
zeroes |= ~mask[i];
}
- if (nbits % 32) {
- zeroes |= ~mask[i] & htonl(~0u << (32 - nbits % 32));
+ if (n_bits % 32) {
+ zeroes |= ~mask[i] & htonl(~0u << (32 - n_bits % 32));
}
- return !zeroes; /* All 'nbits' bits set. */
+ return !zeroes; /* All 'n_bits' bits set. */
}
-static struct trie_node **
+static rcu_trie_ptr *
trie_next_edge(struct trie_node *node, const ovs_be32 value[],
unsigned int ofs)
{
trie_next_node(const struct trie_node *node, const ovs_be32 value[],
unsigned int ofs)
{
- return node->edges[be_get_bit_at(value, ofs)];
+ return ovsrcu_get(struct trie_node *,
+ &node->edges[be_get_bit_at(value, ofs)]);
+}
+
+/* Set the bit at ("MSB 0"-based) offset 'ofs'. 'ofs' can be greater than 31.
+ */
+static void
+be_set_bit_at(ovs_be32 value[], unsigned int ofs)
+{
+ ((uint8_t *)value)[ofs / 8] |= 1u << (7 - ofs % 8);
}
-/* Return the prefix mask length necessary to find the longest-prefix match for
- * the '*value' in the prefix tree 'node'.
- * '*checkbits' is set to the number of bits in the prefix mask necessary to
- * determine a mismatch, in case there are longer prefixes in the tree below
- * the one that matched.
+/* Returns the number of bits in the prefix mask necessary to determine a
+ * mismatch, in case there are longer prefixes in the tree below the one that
+ * matched.
+ * '*plens' will have a bit set for each prefix length that may have matching
+ * rules. The caller is responsible for clearing the '*plens' prior to
+ * calling this.
*/
static unsigned int
-trie_lookup_value(const struct trie_node *node, const ovs_be32 value[],
- unsigned int n_bits, unsigned int *checkbits)
+trie_lookup_value(const rcu_trie_ptr *trie, const ovs_be32 value[],
+ ovs_be32 plens[], unsigned int n_bits)
{
- unsigned int ofs = 0, match_len = 0;
const struct trie_node *prev = NULL;
+ const struct trie_node *node = ovsrcu_get(struct trie_node *, trie);
+ unsigned int match_len = 0; /* Number of matching bits. */
- for (; node; prev = node, node = trie_next_node(node, value, ofs)) {
+ for (; node; prev = node, node = trie_next_node(node, value, match_len)) {
unsigned int eqbits;
/* Check if this edge can be followed. */
- eqbits = prefix_equal_bits(node->prefix, node->nbits, value, ofs);
- ofs += eqbits;
- if (eqbits < node->nbits) { /* Mismatch, nothing more to be found. */
- /* Bit at offset 'ofs' differed. */
- *checkbits = ofs + 1; /* Includes the first mismatching bit. */
- return match_len;
+ eqbits = prefix_equal_bits(node->prefix, node->n_bits, value,
+ match_len);
+ match_len += eqbits;
+ if (eqbits < node->n_bits) { /* Mismatch, nothing more to be found. */
+ /* Bit at offset 'match_len' differed. */
+ return match_len + 1; /* Includes the first mismatching bit. */
}
/* Full match, check if rules exist at this prefix length. */
if (node->n_rules > 0) {
- match_len = ofs;
+ be_set_bit_at(plens, match_len - 1);
}
- if (ofs >= n_bits) {
- *checkbits = n_bits; /* Full prefix. */
- return match_len;
+ if (match_len >= n_bits) {
+ return n_bits; /* Full prefix. */
}
}
- /* node == NULL. Full match so far, but we came to a dead end.
- * need to exclude the other branch if it exists. */
- *checkbits = !prev || trie_is_leaf(prev) ? ofs : ofs + 1;
- return match_len;
+ /* node == NULL. Full match so far, but we tried to follow an
+ * non-existing branch. Need to exclude the other branch if it exists
+ * (it does not if we were called on an empty trie or 'prev' is a leaf
+ * node). */
+ return !prev || trie_is_leaf(prev) ? match_len : match_len + 1;
}
static unsigned int
trie_lookup(const struct cls_trie *trie, const struct flow *flow,
- unsigned int *checkbits)
+ union trie_prefix *plens)
{
const struct mf_field *mf = trie->field;
* field. Some match fields are used for multiple purposes, so we
* must check that the trie is relevant for this flow. */
if (mf_are_prereqs_ok(mf, flow)) {
- return trie_lookup_value(trie->root,
+ return trie_lookup_value(&trie->root,
&((ovs_be32 *)flow)[mf->flow_be32ofs],
- mf->n_bits, checkbits);
+ &plens->be32, mf->n_bits);
}
- *checkbits = 0; /* Value not used in this case. */
- return UINT_MAX;
+ memset(plens, 0xff, sizeof *plens); /* All prefixes, no skipping. */
+ return 0; /* Value not used in this case. */
}
/* Returns the length of a prefix match mask for the field 'mf' in 'minimask'.
minimask_get_prefix_len(const struct minimask *minimask,
const struct mf_field *mf)
{
- unsigned int nbits = 0, mask_tz = 0; /* Non-zero when end of mask seen. */
- uint8_t u32_ofs = mf->flow_be32ofs;
- uint8_t u32_end = u32_ofs + mf->n_bytes / 4;
+ unsigned int n_bits = 0, mask_tz = 0; /* Non-zero when end of mask seen. */
+ uint8_t be32_ofs = mf->flow_be32ofs;
+ uint8_t be32_end = be32_ofs + mf->n_bytes / 4;
- for (; u32_ofs < u32_end; ++u32_ofs) {
- uint32_t mask;
- mask = ntohl((OVS_FORCE ovs_be32)minimask_get(minimask, u32_ofs));
+ for (; be32_ofs < be32_end; ++be32_ofs) {
+ uint32_t mask = ntohl(minimask_get_be32(minimask, be32_ofs));
/* Validate mask, count the mask length. */
if (mask_tz) {
return 0; /* Mask not contiguous. */
}
mask_tz = ctz32(mask);
- nbits += 32 - mask_tz;
+ n_bits += 32 - mask_tz;
}
}
- return nbits;
+ return n_bits;
}
/*
static const ovs_be32 *
minimatch_get_prefix(const struct minimatch *match, const struct mf_field *mf)
{
- return miniflow_get_be32_values(&match->flow) +
- count_1bits(match->flow.map & ((UINT64_C(1) << mf->flow_be32ofs) - 1));
+ size_t u64_ofs = mf->flow_be32ofs / 2;
+
+ return (OVS_FORCE const ovs_be32 *)miniflow_get__(match->flow, u64_ofs)
+ + (mf->flow_be32ofs & 1);
}
/* Insert rule in to the prefix tree.
}
static void
-trie_insert_prefix(struct trie_node **edge, const ovs_be32 *prefix, int mlen)
+trie_insert_prefix(rcu_trie_ptr *edge, const ovs_be32 *prefix, int mlen)
{
struct trie_node *node;
int ofs = 0;
/* Walk the tree. */
- for (; (node = *edge) != NULL;
+ for (; (node = ovsrcu_get_protected(struct trie_node *, edge));
edge = trie_next_edge(node, prefix, ofs)) {
unsigned int eqbits = trie_prefix_equal_bits(node, prefix, ofs, mlen);
ofs += eqbits;
- if (eqbits < node->nbits) {
+ if (eqbits < node->n_bits) {
/* Mismatch, new node needs to be inserted above. */
int old_branch = get_bit_at(node->prefix, eqbits);
+ struct trie_node *new_parent;
- /* New parent node. */
- *edge = trie_branch_create(prefix, ofs - eqbits, eqbits,
- ofs == mlen ? 1 : 0);
-
- /* Adjust old node for its new position in the tree. */
+ new_parent = trie_branch_create(prefix, ofs - eqbits, eqbits,
+ ofs == mlen ? 1 : 0);
+ /* Copy the node to modify it. */
+ node = trie_node_rcu_realloc(node);
+ /* Adjust the new node for its new position in the tree. */
node->prefix <<= eqbits;
- node->nbits -= eqbits;
- (*edge)->edges[old_branch] = node;
+ node->n_bits -= eqbits;
+ ovsrcu_set_hidden(&new_parent->edges[old_branch], node);
/* Check if need a new branch for the new rule. */
if (ofs < mlen) {
- (*edge)->edges[!old_branch]
- = trie_branch_create(prefix, ofs, mlen - ofs, 1);
+ ovsrcu_set_hidden(&new_parent->edges[!old_branch],
+ trie_branch_create(prefix, ofs, mlen - ofs,
+ 1));
}
+ ovsrcu_set(edge, new_parent); /* Publish changes. */
return;
}
/* Full match so far. */
}
}
/* Must insert a new tree branch for the new rule. */
- *edge = trie_branch_create(prefix, ofs, mlen - ofs, 1);
+ ovsrcu_set(edge, trie_branch_create(prefix, ofs, mlen - ofs, 1));
}
/* 'mlen' must be the (non-zero) CIDR prefix length of the 'trie->field' mask
/* 'mlen' must be the (non-zero) CIDR prefix length of the 'trie->field' mask
* in 'rule'. */
static void
-trie_remove_prefix(struct trie_node **root, const ovs_be32 *prefix, int mlen)
+trie_remove_prefix(rcu_trie_ptr *root, const ovs_be32 *prefix, int mlen)
{
struct trie_node *node;
- struct trie_node **edges[sizeof(union mf_value) * 8];
+ rcu_trie_ptr *edges[sizeof(union trie_prefix) * CHAR_BIT];
int depth = 0, ofs = 0;
/* Walk the tree. */
for (edges[0] = root;
- (node = *edges[depth]) != NULL;
+ (node = ovsrcu_get_protected(struct trie_node *, edges[depth]));
edges[++depth] = trie_next_edge(node, prefix, ofs)) {
unsigned int eqbits = trie_prefix_equal_bits(node, prefix, ofs, mlen);
- if (eqbits < node->nbits) {
+ if (eqbits < node->n_bits) {
/* Mismatch, nothing to be removed. This should never happen, as
* only rules in the classifier are ever removed. */
break; /* Log a warning. */
node->n_rules--;
/* Check if can prune the tree. */
- while (!node->n_rules && !(node->edges[0] && node->edges[1])) {
- /* No rules and at most one child node, remove this node. */
- struct trie_node *next;
- next = node->edges[0] ? node->edges[0] : node->edges[1];
+ while (!node->n_rules) {
+ struct trie_node *next,
+ *edge0 = ovsrcu_get_protected(struct trie_node *,
+ &node->edges[0]),
+ *edge1 = ovsrcu_get_protected(struct trie_node *,
+ &node->edges[1]);
+
+ if (edge0 && edge1) {
+ break; /* A branching point, cannot prune. */
+ }
+
+ /* Else have at most one child node, remove this node. */
+ next = edge0 ? edge0 : edge1;
if (next) {
- if (node->nbits + next->nbits > TRIE_PREFIX_BITS) {
+ if (node->n_bits + next->n_bits > TRIE_PREFIX_BITS) {
break; /* Cannot combine. */
}
+ next = trie_node_rcu_realloc(next); /* Modify. */
+
/* Combine node with next. */
- next->prefix = node->prefix | next->prefix >> node->nbits;
- next->nbits += node->nbits;
+ next->prefix = node->prefix | next->prefix >> node->n_bits;
+ next->n_bits += node->n_bits;
}
- trie_node_destroy(node);
/* Update the parent's edge. */
- *edges[depth] = next;
+ ovsrcu_set(edges[depth], next); /* Publish changes. */
+ trie_node_destroy(node);
+
if (next || !depth) {
/* Branch not pruned or at root, nothing more to do. */
break;
}
- node = *edges[--depth];
+ node = ovsrcu_get_protected(struct trie_node *,
+ edges[--depth]);
}
return;
}
* that actually exist in the classifier are ever removed. */
VLOG_WARN("Trying to remove non-existing rule from a prefix trie.");
}
+\f
+
+#define CLS_MATCH_POISON (struct cls_match *)(UINTPTR_MAX / 0xf * 0xb)
+
+void
+cls_match_free_cb(struct cls_match *rule)
+{
+ ovsrcu_set_hidden(&rule->next, CLS_MATCH_POISON);
+ free(rule);
+}