X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fclassifier.c;h=2d1e50bbb48a840a350d485cd2e047f931c34c6c;hb=4d5f814dfb737aae820b8ce70ff0a8b94c291ec3;hp=919e05fca456ebdb3af52bf424eb0d44c64c932a;hpb=81a76618be9ea195a1e4a881ba9591728891d10b;p=sliver-openvswitch.git

diff --git a/lib/classifier.c b/lib/classifier.c
index 919e05fca..2d1e50bbb 100644
--- a/lib/classifier.c
+++ b/lib/classifier.c
@@ -1,5 +1,5 @@
 /*
- * 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.
@@ -16,7 +16,6 @@
 
 #include <config.h>
 #include "classifier.h"
-#include <assert.h>
 #include <errno.h>
 #include <netinet/in.h>
 #include "byte-order.h"
@@ -28,17 +27,25 @@
 #include "packets.h"
 
 static struct cls_table *find_table(const struct classifier *,
-                                    const struct flow_wildcards *);
+                                    const struct minimask *);
 static struct cls_table *insert_table(struct classifier *,
-                                      const struct flow_wildcards *);
+                                      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 flow *,
-                                   uint32_t hash);
-static struct cls_rule *insert_rule(struct cls_table *, struct cls_rule *);
+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)                               \
@@ -54,10 +61,10 @@ static struct cls_rule *next_rule_in_list(struct cls_rule *);
 /* cls_rule. */
 
 /* Initializes 'rule' to match packets specified by 'match' at the given
- * 'priority'.
+ * 'priority'.  'match' must satisfy the invariant described in the comment at
+ * the definition of struct match.
  *
- * '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.) */
@@ -65,30 +72,67 @@ void
 cls_rule_init(struct cls_rule *rule,
               const struct match *match, unsigned int priority)
 {
-    rule->match = *match;
+    minimatch_init(&rule->match, match);
+    rule->priority = priority;
+}
+
+/* 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)
+{
+    minimatch_clone(&rule->match, match);
     rule->priority = priority;
 }
 
+/* Initializes 'dst' as a copy of 'src'.
+ *
+ * The caller must eventually destroy 'rule' with cls_rule_destroy(). */
+void
+cls_rule_clone(struct cls_rule *dst, const struct cls_rule *src)
+{
+    minimatch_clone(&dst->match, &src->match);
+    dst->priority = src->priority;
+}
+
+/* Frees memory referenced by 'rule'.  Doesn't free 'rule' itself (it's
+ * normally embedded into a larger structure).
+ *
+ * ('rule' must not currently be in a classifier.) */
+void
+cls_rule_destroy(struct cls_rule *rule)
+{
+    minimatch_destroy(&rule->match);
+}
+
 /* Returns true if 'a' and 'b' match the same packets at the same priority,
  * false if they differ in some way. */
 bool
 cls_rule_equal(const struct cls_rule *a, const struct cls_rule *b)
 {
-    return a->priority == b->priority && match_equal(&a->match, &b->match);
+    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 match_hash(&rule->match, hash_int(rule->priority, 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)
 {
-    match_format(&rule->match, s, rule->priority);
+    minimatch_format(&rule->match, s, rule->priority);
+}
+
+/* Returns true if 'rule' matches every packet, false otherwise. */
+bool
+cls_rule_is_catchall(const struct cls_rule *rule)
+{
+    return minimask_is_catchall(&rule->match.mask);
 }
 
 /* Initializes 'cls' as a classifier that initially contains no classification
@@ -98,6 +142,7 @@ classifier_init(struct classifier *cls)
 {
     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
@@ -109,9 +154,7 @@ classifier_destroy(struct classifier *cls)
         struct cls_table *table, *next_table;
 
         HMAP_FOR_EACH_SAFE (table, next_table, hmap_node, &cls->tables) {
-            hmap_destroy(&table->rules);
-            hmap_remove(&cls->tables, &table->hmap_node);
-            free(table);
+            destroy_table(cls, table);
         }
         hmap_destroy(&cls->tables);
     }
@@ -137,7 +180,8 @@ classifier_count(const struct classifier *cls)
  * 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 freeing it, etc., as necessary.
+ * is thus responsible for destroying it with cls_rule_destroy(), freeing the
+ * memory block in which it resides, etc., as necessary.
  *
  * 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
@@ -149,12 +193,12 @@ classifier_replace(struct classifier *cls, struct cls_rule *rule)
     struct cls_rule *old_rule;
     struct cls_table *table;
 
-    table = find_table(cls, &rule->match.wc);
+    table = find_table(cls, &rule->match.mask);
     if (!table) {
-        table = insert_table(cls, &rule->match.wc);
+        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++;
@@ -172,18 +216,19 @@ void
 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 free
- * 'rule', if this is desirable. */
+/* 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_rule *head;
     struct cls_table *table;
 
-    table = find_table(cls, &rule->match.wc);
+    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);
@@ -199,8 +244,9 @@ classifier_remove(struct classifier *cls, struct cls_rule *rule)
 
     if (--table->n_table_rules == 0) {
         destroy_table(cls, table);
+    } else {
+        update_tables_after_removal(cls, table, rule->priority);
     }
-
     cls->n_rules--;
 }
 
@@ -214,10 +260,22 @@ classifier_lookup(const struct classifier *cls, const struct flow *flow)
     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 (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 (rule && rule->priority > best->priority) {
+                    best = rule;
+                }
+            }
+            break;
         }
     }
     return best;
@@ -233,13 +291,19 @@ classifier_find_rule_exactly(const struct classifier *cls,
     struct cls_rule *head, *rule;
     struct cls_table *table;
 
-    table = find_table(cls, &target->match.wc);
+    table = find_table(cls, &target->match.mask);
     if (!table) {
         return NULL;
     }
 
+    /* Skip if there is no hope. */
+    if (target->priority > table->max_priority) {
+        return NULL;
+    }
+
     head = find_equal(table, &target->match.flow,
-                      flow_hash(&target->match.flow, 0));
+                      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;
@@ -261,6 +325,7 @@ classifier_find_match_exactly(const struct classifier *cls,
 
     cls_rule_init(&cr, target, priority);
     retval = classifier_find_rule_exactly(cls, &cr);
+    cls_rule_destroy(&cr);
 
     return retval;
 }
@@ -274,18 +339,27 @@ classifier_rule_overlaps(const struct classifier *cls,
 {
     struct cls_table *table;
 
-    HMAP_FOR_EACH (table, hmap_node, &cls->tables) {
-        struct flow_wildcards wc;
+    /* 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;
 
-        flow_wildcards_combine(&wc, &target->match.wc, &table->wc);
+        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
-                    && flow_equal_except(&target->match.flow,
-                                         &rule->match.flow, &wc)) {
+                    && miniflow_equal_in_minimask(&target->match.flow,
+                                                  &rule->match.flow, &mask)) {
                     return true;
                 }
             }
@@ -330,11 +404,11 @@ classifier_rule_overlaps(const struct classifier *cls,
  * Ignores rule->priority. */
 bool
 cls_rule_is_loose_match(const struct cls_rule *rule,
-                        const struct match *criteria)
+                        const struct minimatch *criteria)
 {
-    return (!flow_wildcards_has_extra(&rule->match.wc, &criteria->wc)
-            && flow_equal_except(&rule->match.flow, &criteria->flow,
-                                 &criteria->wc));
+    return (!minimask_has_extra(&rule->match.mask, &criteria->mask)
+            && miniflow_equal_in_minimask(&rule->match.flow, &criteria->flow,
+                                          &criteria->mask));
 }
 
 /* Iteration. */
@@ -343,14 +417,15 @@ static bool
 rule_matches(const struct cls_rule *rule, const struct cls_rule *target)
 {
     return (!target
-            || flow_equal_except(&rule->match.flow, &target->match.flow,
-                                 &target->match.wc));
+            || 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)
 {
-    if (!target || !flow_wildcards_has_extra(&table->wc, &target->match.wc)) {
+    if (!target || !minimask_has_extra(&table->mask, &target->match.mask)) {
         struct cls_rule *rule;
 
         HMAP_FOR_EACH (rule, hmap_node, &table->rules) {
@@ -375,7 +450,7 @@ cls_cursor_init(struct cls_cursor *cursor, const struct classifier *cls,
                 const struct cls_rule *target)
 {
     cursor->cls = cls;
-    cursor->target = target;
+    cursor->target = target && !cls_rule_is_catchall(target) ? target : NULL;
 }
 
 /* Returns the first matching cls_rule in 'cursor''s iteration, or a null
@@ -432,13 +507,13 @@ cls_cursor_next(struct cls_cursor *cursor, struct cls_rule *rule)
 }
 
 static struct cls_table *
-find_table(const struct classifier *cls, const struct flow_wildcards *wc)
+find_table(const struct classifier *cls, const struct minimask *mask)
 {
     struct cls_table *table;
 
-    HMAP_FOR_EACH_IN_BUCKET (table, hmap_node, flow_wildcards_hash(wc, 0),
+    HMAP_FOR_EACH_IN_BUCKET (table, hmap_node, minimask_hash(mask, 0),
                              &cls->tables) {
-        if (flow_wildcards_equal(wc, &table->wc)) {
+        if (minimask_equal(mask, &table->mask)) {
             return table;
         }
     }
@@ -446,15 +521,15 @@ find_table(const struct classifier *cls, const struct flow_wildcards *wc)
 }
 
 static struct cls_table *
-insert_table(struct classifier *cls, const struct flow_wildcards *wc)
+insert_table(struct classifier *cls, const struct minimask *mask)
 {
     struct cls_table *table;
 
     table = xzalloc(sizeof *table);
     hmap_init(&table->rules);
-    table->wc = *wc;
-    table->is_catchall = flow_wildcards_is_catchall(&table->wc);
-    hmap_insert(&cls->tables, &table->hmap_node, flow_wildcards_hash(wc, 0));
+    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;
 }
@@ -462,43 +537,126 @@ insert_table(struct classifier *cls, const struct flow_wildcards *wc)
 static void
 destroy_table(struct classifier *cls, struct cls_table *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)
 {
+    uint32_t hash = flow_hash_in_minimask(flow, &table->mask, 0);
     struct cls_rule *rule;
 
-    if (table->is_catchall) {
-        HMAP_FOR_EACH (rule, hmap_node, &table->rules) {
+    HMAP_FOR_EACH_WITH_HASH (rule, hmap_node, hash, &table->rules) {
+        if (miniflow_equal_flow_in_minimask(&rule->match.flow, flow,
+                                            &table->mask)) {
             return rule;
         }
-    } else {
-        struct flow f;
-
-        f = *flow;
-        flow_zero_wildcards(&f, &table->wc);
-        HMAP_FOR_EACH_WITH_HASH (rule, hmap_node, flow_hash(&f, 0),
-                                 &table->rules) {
-            if (flow_equal(&f, &rule->match.flow)) {
-                return rule;
-            }
-        }
     }
 
     return NULL;
 }
 
 static struct cls_rule *
-find_equal(struct cls_table *table, const struct flow *flow, uint32_t hash)
+find_equal(struct cls_table *table, const struct miniflow *flow, uint32_t hash)
 {
     struct cls_rule *head;
 
     HMAP_FOR_EACH_WITH_HASH (head, hmap_node, hash, &table->rules) {
-        if (flow_equal(&head->match.flow, flow)) {
+        if (miniflow_equal(&head->match.flow, flow)) {
             return head;
         }
     }
@@ -506,17 +664,20 @@ find_equal(struct cls_table *table, const struct flow *flow, uint32_t hash)
 }
 
 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 = flow_hash(&new->match.flow, 0);
+    new->hmap_node.hash = miniflow_hash_in_minimask(&new->match.flow,
+                                                    &new->match.mask, 0);
 
     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);
-        return NULL;
+        goto out;
     } else {
         /* Scan the list for the insertion point that will keep the list in
          * order of decreasing priority. */
@@ -531,18 +692,24 @@ insert_rule(struct cls_table *table, struct cls_rule *new)
 
                 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 *