/*
- * 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 "odp-util.h"
#include "ofp-util.h"
#include "packets.h"
-#include "ovs-thread.h"
-
-static struct cls_table *find_table(const struct classifier *,
- const struct minimask *);
-static struct cls_table *insert_table(struct classifier *,
- const struct minimask *);
-
-static void destroy_table(struct classifier *, struct cls_table *);
-
-static void update_tables_after_insertion(struct classifier *,
- struct cls_table *,
- unsigned int new_priority);
-static void update_tables_after_removal(struct classifier *,
- struct cls_table *,
- unsigned int del_priority);
-
-static struct cls_rule *find_match(const struct cls_table *,
- const struct flow *);
-static struct cls_rule *find_equal(struct cls_table *,
- const struct miniflow *, uint32_t hash);
-static struct cls_rule *insert_rule(struct classifier *,
- struct cls_table *, 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))
-
-static struct cls_rule *next_rule_in_list__(struct cls_rule *);
-static struct cls_rule *next_rule_in_list(struct cls_rule *);
+#include "util.h"
+#include "openvswitch/vlog.h"
+
+VLOG_DEFINE_THIS_MODULE(classifier);
+
+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)
+
+static size_t
+cls_conjunction_set_size(size_t n)
+{
+ return (sizeof(struct cls_conjunction_set)
+ + n * sizeof(struct cls_conjunction));
+}
+
+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);
+ }
+
+ 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(const struct cls_rule *rule, cls_version_t version,
+ const struct cls_conjunction conj[], size_t n)
+{
+ size_t count = miniflow_n_values(rule->match.flow);
+
+ struct 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 classifier *cls,
+ const struct minimask *);
+static struct cls_subtable *insert_subtable(struct classifier *cls,
+ const struct minimask *);
+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);
+
+/* 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;
+}
+
+/* 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 classifier *cls, int trie_idx,
+ const struct mf_field *);
+static unsigned int trie_lookup(const struct cls_trie *, const struct flow *,
+ 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(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(rcu_trie_ptr *, const ovs_be32 *prefix,
+ int mlen);
+static void mask_set_prefix_bits(struct flow_wildcards *, uint8_t be32ofs,
+ unsigned int n_bits);
+static bool mask_prefix_bits_set(const struct flow_wildcards *,
+ uint8_t be32ofs, unsigned int n_bits);
\f
/* cls_rule. */
+static inline void
+cls_rule_init__(struct cls_rule *rule, unsigned int priority)
+{
+ rculist_init(&rule->node);
+ *CONST_CAST(int *, &rule->priority) = priority;
+ rule->cls_match = NULL;
+}
+
/* 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;
+ 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;
+ 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;
+ 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;
+ 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
{
- 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);
+}
+
+/* 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
+cls_rule_make_invisible_in_version(const struct cls_rule *rule,
+ cls_version_t remove_version)
+{
+ ovs_assert(remove_version >= rule->cls_match->add_version);
+
+ cls_match_set_remove_version(rule->cls_match, remove_version);
+}
+
+/* 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)
+classifier_init(struct classifier *cls, const uint8_t *flow_segments)
{
cls->n_rules = 0;
- hmap_init(&cls->tables);
- list_init(&cls->tables_priority);
- hmap_init(&cls->partitions);
- ovs_rwlock_init(&cls->rwlock);
+ cmap_init(&cls->subtables_map);
+ pvector_init(&cls->subtables);
+ cls->n_flow_segments = 0;
+ if (flow_segments) {
+ while (cls->n_flow_segments < CLS_MAX_INDICES
+ && *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)
{
if (cls) {
- struct cls_table *partition, *next_partition;
- struct cls_table *table, *next_table;
+ struct cls_subtable *subtable;
+ int i;
+
+ for (i = 0; i < cls->n_tries; i++) {
+ trie_destroy(&cls->tries[i].root);
+ }
+
+ CMAP_FOR_EACH (subtable, cmap_node, &cls->subtables_map) {
+ destroy_subtable(cls, subtable);
+ }
+ cmap_destroy(&cls->subtables_map);
+
+ pvector_destroy(&cls->subtables);
+ }
+}
+
+/* Set the fields for which prefix lookup should be performed. */
+bool
+classifier_set_prefix_fields(struct classifier *cls,
+ const enum mf_field_id *trie_fields,
+ unsigned int n_fields)
+{
+ 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; 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
+ * enforce these requirements, but the rest of the trie code
+ * depends on the flow_be32ofs to be non-negative and the
+ * field length to be a multiple of 32 bits. */
+ continue;
+ }
- HMAP_FOR_EACH_SAFE (table, next_table, hmap_node, &cls->tables) {
- destroy_table(cls, table);
+ 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;
}
- hmap_destroy(&cls->tables);
+ bitmap_set1(fields.bm, trie_fields[i]);
- HMAP_FOR_EACH_SAFE (partition, next_partition, hmap_node,
- &cls->partitions) {
- hmap_remove(&cls->partitions, &partition->hmap_node);
- free(partition);
+ new_fields[n_tries] = NULL;
+ if (n_tries >= cls->n_tries || field != cls->tries[n_tries].field) {
+ new_fields[n_tries] = field;
+ changed = true;
}
- hmap_destroy(&cls->partitions);
- ovs_rwlock_destroy(&cls->rwlock);
+ 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();
+ }
+
+ /* 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;
+ }
+
+ return false; /* No change. */
}
-/* Returns true if 'cls' contains no classification rules, false otherwise. */
+static void
+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);
+ } else {
+ ovsrcu_set_hidden(&trie->root, NULL);
+ }
+ trie->field = field;
+
+ /* 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;
+ if (plen) {
+ struct cls_match *head;
+
+ 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.
+ * Checking the cmap requires no locking. */
bool
classifier_is_empty(const struct classifier *cls)
{
- return 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)
{
+ /* 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_2words(metadata, metadata >> 32);
+ /* 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 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 classifier *cls, struct cls_table *table,
- 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, table->tag);
- return partition;
-}
-
-/* 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_rule *old_rule;
- struct cls_table *table;
+ 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;
+
+ /* 'new' is initially invisible to lookups. */
+ new = cls_match_alloc(rule, version, conjs, n_conjs);
+
+ CONST_CAST(struct cls_rule *, rule)->cls_match = new;
+
+ subtable = find_subtable(cls, rule->match.mask);
+ if (!subtable) {
+ subtable = insert_subtable(cls, rule->match.mask);
+ }
- table = find_table(cls, &rule->match.mask);
- if (!table) {
- table = insert_table(cls, &rule->match.mask);
+ /* 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]);
+ }
+ }
+
+ /* 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
+ * and they will always match (== their original value does not
+ * matter). */
+ ovs_be32 masked_ports = minimatch_get_ports(&rule->match);
+
+ trie_insert_prefix(&subtable->ports_trie, &masked_ports,
+ subtable->ports_mask_len);
+ }
+
+ /* 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;
+
+ /* 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);
+ }
- old_rule = insert_rule(cls, table, rule);
- if (!old_rule) {
- if (minimask_get_metadata_mask(&rule->match.mask) == OVS_BE64_MAX) {
- ovs_be64 metadata = miniflow_get_metadata(&rule->match.flow);
- rule->partition = create_partition(cls, table, metadata);
+ 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 {
- rule->partition = NULL;
+ /* 'new' is new node after 'prev' */
+ cls_match_insert(prev, iter, new);
}
+ }
- table->n_table_rules++;
- cls->n_rules++;
- } else {
- rule->partition = old_rule->partition;
+ /* 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 old_rule;
+
+ 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)
-{
- struct cls_partition *partition;
- struct cls_rule *head;
- struct cls_table *table;
-
- table = find_table(cls, &rule->match.mask);
- head = find_equal(table, &rule->match.flow, rule->hmap_node.hash);
- if (head != rule) {
- list_remove(&rule->list);
- } else if (list_is_empty(&rule->list)) {
- hmap_remove(&table->rules, &rule->hmap_node);
- } else {
- struct cls_rule *next = CONTAINER_OF(rule->list.next,
- struct cls_rule, list);
+ * 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_match *rule, *prev, *next, *head;
+ struct cls_conjunction_set *conj_set;
+ struct cls_subtable *subtable;
+ 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;
- list_remove(&rule->list);
- hmap_replace(&table->rules, &rule->hmap_node, &next->hmap_node);
+ /* Remove 'cls_rule' from the subtable's rules list. */
+ rculist_remove(CONST_CAST(struct rculist *, &cls_rule->node));
+
+ 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(&cls_rule->match);
- partition = rule->partition;
- if (partition) {
- tag_tracker_subtract(&partition->tracker, &partition->tags,
- table->tag);
- if (!partition->tags) {
- hmap_remove(&cls->partitions, &partition->hmap_node);
- free(partition);
+ 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], cls_rule, subtable->trie_plen[i]);
}
}
- if (--table->n_table_rules == 0) {
- destroy_table(cls, table);
+ /* Remove rule node from indices. */
+ for (i = 0; i < subtable->n_indices; i++) {
+ cmap_remove(&subtable->indices[i], &rule->index_nodes[i], ihash[i]);
+ }
+ n_rules = cmap_remove(&subtable->rules, &rule->cmap_node, hash);
+
+ if (n_rules == 0) {
+ destroy_subtable(cls, subtable);
} else {
- update_tables_after_removal(cls, table, rule->priority);
+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;
+
+ 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 (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--;
+
+ return cls_rule;
}
-/* 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)
-{
- const struct cls_partition *partition;
- struct cls_table *table;
- struct cls_rule *best;
- tag_type tags;
-
- /* Determine 'tags' such that, if 'table->tag' doesn't intersect them, then
- * 'flow' cannot possibly match in 'table':
- *
- * - 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 table that includes flow->metadata in its mask.
- *
- * In either case, we always need to search any cls_tables that do not
- * include flow->metadata in its mask. One way to do that would be to
- * check the "cls_table"s explicitly for that, but that would require an
- * extra branch per table. Instead, we mark such a cls_table's 'tags' as
- * TAG_ALL and make sure that 'tags' is never empty. This means that
- * 'tags' always intersects such a cls_table'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;
-
- best = NULL;
- LIST_FOR_EACH (table, list_node, &cls->tables_priority) {
- struct cls_rule *rule;
-
- if (!tag_intersects(tags, table->tag)) {
+/* Prefix tree context. Valid when 'lookup_done' is true. Can skip all
+ * 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 maskbits; /* Prefix length needed to avoid false matches. */
+ union trie_prefix match_plens; /* Bitmask of prefix lengths with possible
+ * matches. */
+};
+
+static void
+trie_ctx_init(struct trie_ctx *ctx, const struct cls_trie *trie)
+{
+ ctx->trie = trie;
+ ctx->be32ofs = trie->field->flow_be32ofs;
+ ctx->lookup_done = false;
+}
+
+struct conjunctive_match {
+ struct hmap_node hmap_node;
+ uint32_t id;
+ uint64_t clauses;
+};
+
+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;
+ }
+
+ for (c = set->conj; c < &set->conj[set->n]; c++) {
+ struct conjunctive_match *cm;
+ uint32_t hash;
+
+ if (c->n_clauses > max_n_clauses) {
continue;
}
- rule = find_match(table, flow);
- if (wc) {
- flow_wildcards_fold_minimask(wc, &table->mask);
+ 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);
}
- if (rule) {
- best = rule;
- LIST_FOR_EACH_CONTINUE (table, list_node, &cls->tables_priority) {
- if (table->max_priority <= best->priority) {
- /* Tables in descending priority order,
- * can not find anything better. */
- return best;
- }
- if (!tag_intersects(tags, table->tag)) {
- continue;
+ cm->clauses |= UINT64_C(1) << c->clause;
+ if (cm->clauses == UINT64_MAX) {
+ *idp = cm->id;
+ return true;
+ }
+ }
+ return false;
+}
+
+static void
+free_conjunctive_matches(struct hmap *matches,
+ struct conjunctive_match *cm_stubs, size_t n_cm_stubs)
+{
+ if (hmap_count(matches) > n_cm_stubs) {
+ struct conjunctive_match *cm, *next;
+
+ HMAP_FOR_EACH_SAFE (cm, next, hmap_node, matches) {
+ if (!(cm >= cm_stubs && cm < &cm_stubs[n_cm_stubs])) {
+ free(cm);
+ }
+ }
+ }
+ hmap_destroy(matches);
+}
+
+/* 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 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]);
+ }
+
+ /* 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;
- rule = find_match(table, flow);
- if (wc) {
- flow_wildcards_fold_minimask(wc, &table->mask);
+ /* Keep track of the highest-priority soft match. */
+ if (soft_pri < match->priority) {
+ soft_pri = match->priority;
+ }
+ }
+ }
+
+ /* 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;
+ }
+
+ /* 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. */
+
+ /* 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;
+ }
+
+ /* 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;
}
- if (rule && rule->priority > best->priority) {
- best = 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;
}
- break;
}
}
- return best;
+
+ 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 *
+const struct cls_rule *
classifier_find_rule_exactly(const struct classifier *cls,
- const struct cls_rule *target)
+ const struct cls_rule *target,
+ cls_version_t version)
{
- struct cls_rule *head, *rule;
- struct cls_table *table;
+ const struct cls_match *head, *rule;
+ const struct cls_subtable *subtable;
- table = find_table(cls, &target->match.mask);
- if (!table) {
+ subtable = find_subtable(cls, target->match.mask);
+ if (!subtable) {
return NULL;
}
- /* Skip if there is no hope. */
- if (target->priority > table->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(table, &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 : 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)
+ const struct cls_rule *target, cls_version_t version)
{
- struct cls_table *table;
-
- /* Iterate tables in the descending max priority order. */
- LIST_FOR_EACH (table, list_node, &cls->tables_priority) {
- uint32_t storage[FLOW_U32S];
- struct minimask mask;
- struct cls_rule *head;
-
- if (target->priority > table->max_priority) {
- break; /* Can skip this and the rest of the tables. */
- }
-
- minimask_combine(&mask, &target->match.mask, &table->mask, storage);
- HMAP_FOR_EACH (head, hmap_node, &table->rules) {
- struct cls_rule *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->match.flow, &mask)) {
- return true;
- }
+ struct cls_subtable *subtable;
+
+ /* Iterate subtables in the descending max priority order. */
+ PVECTOR_FOR_EACH_PRIORITY (subtable, target->priority - 1, 2,
+ sizeof(struct cls_subtable), &cls->subtables) {
+ 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_rule *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->match.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_rule *
-search_table(const struct cls_table *table, const struct cls_rule *target)
+static const struct cls_rule *
+search_subtable(const struct cls_subtable *subtable,
+ struct cls_cursor *cursor)
{
- if (!target || !minimask_has_extra(&table->mask, &target->match.mask)) {
- struct cls_rule *rule;
+ if (!cursor->target
+ || !minimask_has_extra(&subtable->mask, cursor->target->match.mask)) {
+ const struct cls_rule *rule;
- HMAP_FOR_EACH (rule, hmap_node, &table->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)
+struct cls_cursor
+cls_cursor_start(const struct classifier *cls, const struct cls_rule *target,
+ cls_version_t version)
{
- cursor->cls = cls;
- cursor->target = target && !cls_rule_is_catchall(target) ? target : NULL;
-}
+ struct cls_cursor cursor;
+ struct cls_subtable *subtable;
-/* 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_table *table;
+ 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);
- HMAP_FOR_EACH (table, hmap_node, &cursor->cls->tables) {
- struct cls_rule *rule = search_table(table, cursor->target);
if (rule) {
- cursor->table = table;
- return 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_rule *rule = CONST_CAST(struct cls_rule *, rule_);
- const struct cls_table *table;
- struct cls_rule *next;
-
- next = next_rule_in_list__(rule);
- if (next->priority < rule->priority) {
- return next;
- }
+ const struct cls_rule *rule;
+ const struct cls_subtable *subtable;
- /* 'next' is the head of the list, that is, the rule that is included in
- * the table'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->table->rules) {
- if (rule_matches(rule, cursor->target)) {
+ 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;
}
}
- table = cursor->table;
- HMAP_FOR_EACH_CONTINUE (table, hmap_node, &cursor->cls->tables) {
- rule = search_table(table, cursor->target);
+ PVECTOR_CURSOR_FOR_EACH_CONTINUE (subtable, &cursor->subtables) {
+ rule = search_subtable(subtable, cursor);
if (rule) {
- cursor->table = table;
+ cursor->subtable = subtable;
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_table *
-find_table(const struct classifier *cls, const struct minimask *mask)
+static struct cls_subtable *
+find_subtable(const struct classifier *cls, const struct minimask *mask)
{
- struct cls_table *table;
+ struct cls_subtable *subtable;
- HMAP_FOR_EACH_IN_BUCKET (table, hmap_node, minimask_hash(mask, 0),
- &cls->tables) {
- if (minimask_equal(mask, &table->mask)) {
- return table;
+ 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;
}
-static struct cls_table *
-insert_table(struct classifier *cls, const struct minimask *mask)
+/* 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 classifier *cls, const struct minimask *mask)
{
uint32_t hash = minimask_hash(mask, 0);
- struct cls_table *table;
+ struct cls_subtable *subtable;
+ int i, index = 0;
+ struct flowmap stage_map;
+ uint8_t prev;
+ size_t count = miniflow_n_values(&mask->masks);
+
+ 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. */
+ prev = 0;
+ for (i = 0; i < cls->n_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 (!flowmap_is_empty(stage_map)) {
+ cmap_init(&subtable->indices[index]);
+ *CONST_CAST(struct flowmap *, &subtable->index_maps[index])
+ = stage_map;
+ index++;
+ }
+ prev = cls->flow_segments[i];
+ }
+ /* 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) {
+ if (flowmap_equal(subtable->index_maps[index],
+ subtable->index_maps[index - 1])) {
+ --index;
+ cmap_destroy(&subtable->indices[index]);
+ }
+ }
+ *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,
+ cls->tries[i].field);
+ }
- table = xzalloc(sizeof *table);
- hmap_init(&table->rules);
- minimask_clone(&table->mask, mask);
- hmap_insert(&cls->tables, &table->hmap_node, minimask_hash(mask, 0));
- list_push_back(&cls->tables_priority, &table->list_node);
- table->tag = (minimask_get_metadata_mask(mask) == OVS_BE64_MAX
- ? tag_create_deterministic(hash)
- : TAG_ALL);
+ /* Ports trie. */
+ ovsrcu_set_hidden(&subtable->ports_trie, NULL);
+ *CONST_CAST(int *, &subtable->ports_mask_len)
+ = 32 - ctz32(ntohl(MINIFLOW_GET_BE32(&mask->masks, tp_src)));
- return table;
+ /* 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_table(struct classifier *cls, struct cls_table *table)
+destroy_subtable(struct classifier *cls, struct cls_subtable *subtable)
{
- minimask_destroy(&table->mask);
- hmap_remove(&cls->tables, &table->hmap_node);
- hmap_destroy(&table->rules);
- list_remove(&table->list_node);
- free(table);
+ int i;
+
+ pvector_remove(&cls->subtables, subtable);
+ 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++) {
+ cmap_destroy(&subtable->indices[i]);
+ }
+ cmap_destroy(&subtable->rules);
+ ovsrcu_postpone(free, subtable);
}
-/* This function performs the following updates for 'table' in 'cls' following
- * the addition of a new rule with priority 'new_priority' to 'table':
- *
- * - Update 'table->max_priority' and 'table->max_count' if necessary.
- *
- * - Update 'table''s position in 'cls->tables_priority' if necessary.
- *
- * This function should only be called after adding a new rule, not after
- * replacing a rule by an identical one or modifying a rule in-place. */
-static void
-update_tables_after_insertion(struct classifier *cls, struct cls_table *table,
- unsigned int new_priority)
-{
- if (new_priority == table->max_priority) {
- ++table->max_count;
- } else if (new_priority > table->max_priority) {
- struct cls_table *iter;
-
- table->max_priority = new_priority;
- table->max_count = 1;
-
- /* Possibly move 'table' earlier in the priority list. If we break out
- * of the loop, then 'table' should be moved just after that 'iter'.
- * If the loop terminates normally, then 'iter' will be the list head
- * and we'll move table just after that (e.g. to the front of the
- * list). */
- iter = table;
- LIST_FOR_EACH_REVERSE_CONTINUE (iter, list_node,
- &cls->tables_priority) {
- if (iter->max_priority >= table->max_priority) {
- break;
- }
- }
+static unsigned int be_get_bit_at(const ovs_be32 value[], unsigned int ofs);
- /* Move 'table' just after 'iter' (unless it's already there). */
- if (iter->list_node.next != &table->list_node) {
- list_splice(iter->list_node.next,
- &table->list_node, table->list_node.next);
+/* 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 flowmap range_map, const struct flow *flow,
+ struct flow_wildcards *wc)
+{
+ int j;
+
+ /* Check if we could avoid fully unwildcarding the next level of
+ * 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, 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];
+
+ /* 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;
+ }
+ /* Can skip if the field is already unwildcarded. */
+ if (mask_prefix_bits_set(wc, ctx->be32ofs, ctx->maskbits)) {
+ return true;
+ }
+ }
}
}
+ return false;
}
-/* This function performs the following updates for 'table' in 'cls' following
- * the deletion of a rule with priority 'del_priority' from 'table':
- *
- * - Update 'table->max_priority' and 'table->max_count' if necessary.
- *
- * - Update 'table''s position in 'cls->tables_priority' if necessary.
+/* 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 should only be called after removing a rule, not after
- * replacing a rule by an identical one or modifying a rule in-place. */
-static void
-update_tables_after_removal(struct classifier *cls, struct cls_table *table,
- unsigned int del_priority)
+ * This function is equivalent to miniflow_equal_flow_in_minimask(flow,
+ * target, mask) but this is faster because of the invariant that
+ * flow->map and mask->masks.map are the same, and that this version
+ * takes the 'wc'. */
+static inline bool
+miniflow_and_mask_matches_flow(const struct miniflow *flow,
+ const struct minimask *mask,
+ const struct flow *target)
{
- struct cls_table *iter;
+ 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;
- if (del_priority == table->max_priority && --table->max_count == 0) {
- struct cls_rule *head;
+ FLOWMAP_FOR_EACH_MAP (map, mask->masks.map) {
+ size_t idx;
- table->max_priority = 0;
- HMAP_FOR_EACH (head, hmap_node, &table->rules) {
- if (head->priority > table->max_priority) {
- table->max_priority = head->priority;
- table->max_count = 1;
- } else if (head->priority == table->max_priority) {
- ++table->max_count;
+ MAP_FOR_EACH_INDEX (idx, map) {
+ if ((*flowp++ ^ target_u64[idx]) & *maskp++) {
+ return false;
}
}
+ target_u64 += MAP_T_BITS;
+ }
+ return true;
+}
- /* Possibly move 'table' later in the priority list. If we break out
- * of the loop, then 'table' should be moved just before that 'iter'.
- * If the loop terminates normally, then 'iter' will be the list head
- * and we'll move table just before that (e.g. to the back of the
- * list). */
- iter = table;
- LIST_FOR_EACH_CONTINUE (iter, list_node, &cls->tables_priority) {
- if (iter->max_priority <= table->max_priority) {
- break;
+static inline const struct cls_match *
+find_match(const struct cls_subtable *subtable, cls_version_t version,
+ const struct flow *flow, uint32_t hash)
+{
+ const struct cls_match *head, *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;
+ }
}
}
+ }
- /* Move 'table' just before 'iter' (unless it's already there). */
- if (iter->list_node.prev != &table->list_node) {
- list_splice(&iter->list_node,
- &table->list_node, table->list_node.next);
+ return NULL;
+}
+
+/* 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 struct cls_rule *
-find_match(const struct cls_table *table, const struct flow *flow)
+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)
{
- uint32_t hash = flow_hash_in_minimask(flow, &table->mask, 0);
- struct cls_rule *rule;
+ if (OVS_UNLIKELY(!wc)) {
+ return find_match(subtable, version, flow,
+ flow_hash_in_minimask(flow, &subtable->mask, 0));
+ }
- HMAP_FOR_EACH_WITH_HASH (rule, hmap_node, hash, &table->rules) {
- if (minimatch_matches_flow(&rule->match, flow)) {
- return rule;
+ 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++) {
+ const struct cmap_node *inode;
+
+ 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;
+ }
+
+ /* 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) {
+ goto no_match;
+ }
+
+ /* If we have narrowed down to a single rule already, check whether
+ * that rule matches. Either way, we're done.
+ *
+ * (Rare) hash collisions may cause us to miss the opportunity for this
+ * optimization. */
+ 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;
+ }
+ }
+ }
+ return NULL;
}
}
+ /* Trie check for the final range. */
+ 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) {
+ /* 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, plens, mask;
+
+ mask = MINIFLOW_GET_BE32(&subtable->mask.masks, tp_src);
+ value = ((OVS_FORCE ovs_be32 *)flow)[TP_PORTS_OFS32] & mask;
+ mbits = trie_lookup_value(&subtable->ports_trie, &value, &plens, 32);
+
+ ((OVS_FORCE ovs_be32 *)&wc->masks)[TP_PORTS_OFS32] |=
+ mask & be32_prefix_mask(mbits);
+
+ goto no_match;
+ }
+ /* Must unwildcard all the fields, as they were looked at. */
+ flow_wildcards_fold_minimask(wc, &subtable->mask);
+ return rule;
+
+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_rule *
-find_equal(struct cls_table *table, const struct miniflow *flow, uint32_t hash)
+static struct cls_match *
+find_equal(const struct cls_subtable *subtable, const struct miniflow *flow,
+ uint32_t hash)
{
- struct cls_rule *head;
+ struct cls_match *head;
- HMAP_FOR_EACH_WITH_HASH (head, hmap_node, hash, &table->rules) {
- if (miniflow_equal(&head->match.flow, flow)) {
+ CMAP_FOR_EACH_WITH_HASH (head, cmap_node, hash, &subtable->rules) {
+ if (miniflow_equal(&head->flow, flow)) {
return head;
}
}
return NULL;
}
+\f
+/* A longest-prefix match tree. */
-static struct cls_rule *
-insert_rule(struct classifier *cls,
- struct cls_table *table, struct cls_rule *new)
+/* 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
+ * the most significant bit of the first byte. The offset can be read as
+ * "how many bits to skip from the start of the prefix starting at 'pr'". */
+static uint32_t
+raw_get_prefix(const ovs_be32 pr[], unsigned int ofs, unsigned int plen)
{
- struct cls_rule *head;
- struct cls_rule *old = NULL;
+ uint32_t prefix;
- new->hmap_node.hash = miniflow_hash_in_minimask(&new->match.flow,
- &new->match.mask, 0);
+ pr += ofs / 32; /* Where to start. */
+ ofs %= 32; /* How many bits to skip at 'pr'. */
- head = find_equal(table, &new->match.flow, new->hmap_node.hash);
- if (!head) {
- hmap_insert(&table->rules, &new->hmap_node, new->hmap_node.hash);
- list_init(&new->list);
- goto out;
- } else {
- /* Scan the list for the insertion point that will keep the list in
- * order of decreasing priority. */
- struct cls_rule *rule;
- FOR_EACH_RULE_IN_LIST (rule, head) {
- if (new->priority >= rule->priority) {
- if (rule == head) {
- /* 'new' is the new highest-priority flow in the list. */
- hmap_replace(&table->rules,
- &rule->hmap_node, &new->hmap_node);
- }
+ prefix = ntohl(*pr) << ofs; /* Get the first 32 - ofs bits. */
+ if (plen > 32 - ofs) { /* Need more than we have already? */
+ prefix |= ntohl(*++pr) >> (32 - ofs);
+ }
+ /* Return with possible unwanted bits at the end. */
+ return prefix;
+}
- if (new->priority == rule->priority) {
- list_replace(&new->list, &rule->list);
- old = rule;
- goto out;
- } else {
- list_insert(&rule->list, &new->list);
- goto out;
- }
- }
+/* Return min(TRIE_PREFIX_BITS, plen) bits of the 'prefix', starting at bit
+ * offset 'ofs'. Prefixes are in the network byte order, and the offset 0
+ * corresponds to the most significant bit of the first byte. The offset can
+ * be read as "how many bits to skip from the start of the prefix starting at
+ * 'pr'". */
+static uint32_t
+trie_get_prefix(const ovs_be32 pr[], unsigned int ofs, unsigned int plen)
+{
+ if (!plen) {
+ return 0;
+ }
+ if (plen > TRIE_PREFIX_BITS) {
+ plen = TRIE_PREFIX_BITS; /* Get at most TRIE_PREFIX_BITS. */
+ }
+ /* Return with unwanted bits cleared. */
+ return raw_get_prefix(pr, ofs, plen) & ~0u << (32 - plen);
+}
+
+/* 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 n_bits, const ovs_be32 value[],
+ unsigned int ofs)
+{
+ 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 - n_bits));
+}
+
+/* Return the number of equal bits in 'node' prefix and a 'prefix' of length
+ * 'plen', starting at "MSB 0"-based offset 'ofs'. */
+static unsigned int
+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->n_bits, plen - ofs),
+ prefix, ofs);
+}
+
+/* Return the bit at ("MSB 0"-based) offset 'ofs' as an int. 'ofs' can
+ * be greater than 31. */
+static unsigned int
+be_get_bit_at(const ovs_be32 value[], unsigned int ofs)
+{
+ return (((const uint8_t *)value)[ofs / 8] >> (7 - ofs % 8)) & 1u;
+}
+
+/* Return the bit at ("MSB 0"-based) offset 'ofs' as an int. 'ofs' must
+ * be between 0 and 31, inclusive. */
+static unsigned int
+get_bit_at(const uint32_t prefix, unsigned int ofs)
+{
+ return (prefix >> (31 - ofs)) & 1u;
+}
+
+/* Create new branch. */
+static struct trie_node *
+trie_branch_create(const ovs_be32 *prefix, unsigned int ofs, unsigned int plen,
+ unsigned int n_rules)
+{
+ struct trie_node *node = xmalloc(sizeof *node);
+
+ node->prefix = trie_get_prefix(prefix, ofs, plen);
+
+ if (plen <= TRIE_PREFIX_BITS) {
+ 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,
+ ofs + TRIE_PREFIX_BITS,
+ plen - TRIE_PREFIX_BITS,
+ n_rules);
+ int bit = get_bit_at(subnode->prefix, 0);
+ 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(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)
+{
+ struct trie_node *new_node = xmalloc(sizeof *node);
+
+ *new_node = *node;
+ trie_node_destroy(node);
+
+ return new_node;
+}
+
+static void
+trie_destroy(rcu_trie_ptr *trie)
+{
+ struct trie_node *node = ovsrcu_get_protected(struct trie_node *, trie);
+
+ if (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)
+{
+ /* 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 n_bits)
+{
+ ovs_be32 *mask = &((ovs_be32 *)&wc->masks)[be32ofs];
+ unsigned int i;
+
+ for (i = 0; i < n_bits / 32; i++) {
+ mask[i] = OVS_BE32_MAX;
+ }
+ 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 n_bits)
+{
+ ovs_be32 *mask = &((ovs_be32 *)&wc->masks)[be32ofs];
+ unsigned int i;
+ ovs_be32 zeroes = 0;
+
+ for (i = 0; i < n_bits / 32; i++) {
+ zeroes |= ~mask[i];
+ }
+ if (n_bits % 32) {
+ zeroes |= ~mask[i] & htonl(~0u << (32 - n_bits % 32));
+ }
+
+ return !zeroes; /* All 'n_bits' bits set. */
+}
+
+static rcu_trie_ptr *
+trie_next_edge(struct trie_node *node, const ovs_be32 value[],
+ unsigned int ofs)
+{
+ return node->edges + be_get_bit_at(value, ofs);
+}
+
+static const struct trie_node *
+trie_next_node(const struct trie_node *node, const ovs_be32 value[],
+ unsigned int 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);
+}
+
+/* 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 rcu_trie_ptr *trie, const ovs_be32 value[],
+ ovs_be32 plens[], unsigned int n_bits)
+{
+ 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, match_len)) {
+ unsigned int eqbits;
+ /* Check if this edge can be followed. */
+ 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) {
+ be_set_bit_at(plens, match_len - 1);
+ }
+ if (match_len >= n_bits) {
+ return n_bits; /* Full prefix. */
}
+ }
+ /* 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,
+ union trie_prefix *plens)
+{
+ const struct mf_field *mf = trie->field;
+
+ /* Check that current flow matches the prerequisites for the trie
+ * 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,
+ &((ovs_be32 *)flow)[mf->flow_be32ofs],
+ &plens->be32, mf->n_bits);
+ }
+ 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'.
+ * Returns the u32 offset to the miniflow data in '*miniflow_index', if
+ * 'miniflow_index' is not NULL. */
+static unsigned int
+minimask_get_prefix_len(const struct minimask *minimask,
+ const struct mf_field *mf)
+{
+ 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 (; be32_ofs < be32_end; ++be32_ofs) {
+ uint32_t mask = ntohl(minimask_get_be32(minimask, be32_ofs));
- /* Insert 'new' at the end of the list. */
- list_push_back(&head->list, &new->list);
+ /* Validate mask, count the mask length. */
+ if (mask_tz) {
+ if (mask) {
+ return 0; /* No bits allowed after mask ended. */
+ }
+ } else {
+ if (~mask & (~mask + 1)) {
+ return 0; /* Mask not contiguous. */
+ }
+ mask_tz = ctz32(mask);
+ n_bits += 32 - mask_tz;
+ }
}
- out:
- if (!old) {
- update_tables_after_insertion(cls, table, new->priority);
+ return n_bits;
+}
+
+/*
+ * This is called only when mask prefix is known to be CIDR and non-zero.
+ * Relies on the fact that the flow and mask have the same map, and since
+ * the mask is CIDR, the storage for the flow field exists even if it
+ * happened to be zeros.
+ */
+static const ovs_be32 *
+minimatch_get_prefix(const struct minimatch *match, const struct mf_field *mf)
+{
+ 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.
+ * 'mlen' must be the (non-zero) CIDR prefix length of the 'trie->field' mask
+ * in 'rule'. */
+static void
+trie_insert(struct cls_trie *trie, const struct cls_rule *rule, int mlen)
+{
+ trie_insert_prefix(&trie->root,
+ minimatch_get_prefix(&rule->match, trie->field), mlen);
+}
+
+static void
+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 = 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->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 = 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->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) {
+ 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. */
+
+ if (ofs == mlen) {
+ /* Full match at the current node, rule needs to be added here. */
+ node->n_rules++;
+ return;
+ }
}
- return old;
+ /* Must insert a new tree branch for the new rule. */
+ ovsrcu_set(edge, trie_branch_create(prefix, ofs, mlen - ofs, 1));
}
-static struct cls_rule *
-next_rule_in_list__(struct cls_rule *rule)
+/* 'mlen' must be the (non-zero) CIDR prefix length of the 'trie->field' mask
+ * in 'rule'. */
+static void
+trie_remove(struct cls_trie *trie, const struct cls_rule *rule, int mlen)
{
- struct cls_rule *next = OBJECT_CONTAINING(rule->list.next, next, list);
- return next;
+ trie_remove_prefix(&trie->root,
+ minimatch_get_prefix(&rule->match, trie->field), mlen);
+}
+
+/* 'mlen' must be the (non-zero) CIDR prefix length of the 'trie->field' mask
+ * in 'rule'. */
+static void
+trie_remove_prefix(rcu_trie_ptr *root, const ovs_be32 *prefix, int mlen)
+{
+ struct trie_node *node;
+ rcu_trie_ptr *edges[sizeof(union trie_prefix) * CHAR_BIT];
+ int depth = 0, ofs = 0;
+
+ /* Walk the tree. */
+ for (edges[0] = root;
+ (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->n_bits) {
+ /* Mismatch, nothing to be removed. This should never happen, as
+ * only rules in the classifier are ever removed. */
+ break; /* Log a warning. */
+ }
+ /* Full match so far. */
+ ofs += eqbits;
+
+ if (ofs == mlen) {
+ /* Full prefix match at the current node, remove rule here. */
+ if (!node->n_rules) {
+ break; /* Log a warning. */
+ }
+ node->n_rules--;
+
+ /* Check if can prune the tree. */
+ 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->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->n_bits;
+ next->n_bits += node->n_bits;
+ }
+ /* Update the parent's edge. */
+ 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 = ovsrcu_get_protected(struct trie_node *,
+ edges[--depth]);
+ }
+ return;
+ }
+ }
+ /* Cannot go deeper. This should never happen, since only rules
+ * 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)
-static struct cls_rule *
-next_rule_in_list(struct cls_rule *rule)
+void
+cls_match_free_cb(struct cls_match *rule)
{
- struct cls_rule *next = next_rule_in_list__(rule);
- return next->priority < rule->priority ? next : NULL;
+ ovsrcu_set_hidden(&rule->next, CLS_MATCH_POISON);
+ free(rule);
}
projects / cascardo / ovs.git / blobdiff