/*
- * Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
+ * Copyright (c) 2009, 2010, 2011, 2012, 2013 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 <assert.h>
#include <errno.h>
#include <netinet/in.h>
#include "byte-order.h"
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 cls_table *, struct cls_rule *);
+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) \
{
cls->n_rules = 0;
hmap_init(&cls->tables);
+ list_init(&cls->tables_priority);
}
/* Destroys 'cls'. Rules within 'cls', if any, are not freed; this is the
table = insert_table(cls, &rule->match.mask);
}
- old_rule = insert_rule(table, rule);
+ old_rule = insert_rule(cls, table, rule);
if (!old_rule) {
table->n_table_rules++;
cls->n_rules++;
classifier_insert(struct classifier *cls, struct cls_rule *rule)
{
struct cls_rule *displaced_rule = classifier_replace(cls, rule);
- assert(!displaced_rule);
+ ovs_assert(!displaced_rule);
}
/* Removes 'rule' from 'cls'. It is the caller's responsibility to destroy
if (--table->n_table_rules == 0) {
destroy_table(cls, table);
+ } else {
+ update_tables_after_removal(cls, table, rule->priority);
}
-
cls->n_rules--;
}
/* 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. */
+ * 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)
+classifier_lookup(const struct classifier *cls, const struct flow *flow,
+ struct flow_wildcards *wc)
{
struct cls_table *table;
struct cls_rule *best;
best = NULL;
- HMAP_FOR_EACH (table, hmap_node, &cls->tables) {
+ LIST_FOR_EACH (table, list_node, &cls->tables_priority) {
struct cls_rule *rule = find_match(table, flow);
- if (rule && (!best || rule->priority > best->priority)) {
+
+ if (wc) {
+ flow_wildcards_fold_minimask(wc, &table->mask);
+ }
+ 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;
+ }
+ rule = find_match(table, flow);
+ if (wc) {
+ flow_wildcards_fold_minimask(wc, &table->mask);
+ }
+ if (rule && rule->priority > best->priority) {
+ best = rule;
+ }
+ }
+ break;
}
}
return best;
return NULL;
}
+ /* Skip if there is no hope. */
+ if (target->priority > table->max_priority) {
+ return NULL;
+ }
+
head = find_equal(table, &target->match.flow,
miniflow_hash_in_minimask(&target->match.flow,
&target->match.mask, 0));
{
struct cls_table *table;
- HMAP_FOR_EACH (table, hmap_node, &cls->tables) {
+ /* 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)) {
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);
return table;
}
minimask_destroy(&table->mask);
hmap_remove(&cls->tables, &table->hmap_node);
hmap_destroy(&table->rules);
+ list_remove(&table->list_node);
free(table);
}
+/* 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;
+ }
+ }
+
+ /* 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);
+ }
+ }
+}
+
+/* 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.
+ *
+ * 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)
+{
+ struct cls_table *iter;
+
+ if (del_priority == table->max_priority && --table->max_count == 0) {
+ struct cls_rule *head;
+
+ 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;
+ }
+ }
+
+ /* 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;
+ }
+ }
+
+ /* 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);
+ }
+ }
+}
+
static struct cls_rule *
find_match(const struct cls_table *table, const struct flow *flow)
{
}
static struct cls_rule *
-insert_rule(struct cls_table *table, struct cls_rule *new)
+insert_rule(struct classifier *cls,
+ struct cls_table *table, struct cls_rule *new)
{
struct cls_rule *head;
+ struct cls_rule *old = NULL;
new->hmap_node.hash = miniflow_hash_in_minimask(&new->match.flow,
&new->match.mask, 0);
if (!head) {
hmap_insert(&table->rules, &new->hmap_node, new->hmap_node.hash);
list_init(&new->list);
- return NULL;
+ goto out;
} else {
/* Scan the list for the insertion point that will keep the list in
* order of decreasing priority. */
if (new->priority == rule->priority) {
list_replace(&new->list, &rule->list);
- return rule;
+ old = rule;
+ goto out;
} else {
list_insert(&rule->list, &new->list);
- return NULL;
+ goto out;
}
}
}
/* Insert 'new' at the end of the list. */
list_push_back(&head->list, &new->list);
- return NULL;
}
+
+ out:
+ if (!old) {
+ update_tables_after_insertion(cls, table, new->priority);
+ }
+ return old;
}
static struct cls_rule *