1 /* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
4 * We are making the OpenFlow specification and associated documentation
5 * (Software) available for public use and benefit with the expectation
6 * that others will use, modify and enhance the Software and contribute
7 * those enhancements back to the community. However, since we would
8 * like to make the Software available for broadest use, with as few
9 * restrictions as possible permission is hereby granted, free of
10 * charge, to any person obtaining a copy of this Software to deal in
11 * the Software under the copyrights without restriction, including
12 * without limitation the rights to use, copy, modify, merge, publish,
13 * distribute, sublicense, and/or sell copies of the Software, and to
14 * permit persons to whom the Software is furnished to do so, subject to
15 * the following conditions:
17 * The above copyright notice and this permission notice shall be
18 * included in all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
24 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
25 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
26 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 * The name and trademarks of copyright holder(s) may NOT be used in
30 * advertising or publicity pertaining to the Software or any
31 * derivatives without specific, written prior permission.
43 struct sw_table_hash {
47 unsigned int bucket_mask; /* Number of buckets minus 1. */
48 struct sw_flow **buckets;
51 static struct sw_flow **find_bucket(struct sw_table *swt,
52 const struct sw_flow_key *key)
54 struct sw_table_hash *th = (struct sw_table_hash *) swt;
55 unsigned int crc = crc32_calculate(&th->crc32, key,
56 offsetof(struct sw_flow_key, wildcards));
57 return &th->buckets[crc & th->bucket_mask];
60 static struct sw_flow *table_hash_lookup(struct sw_table *swt,
61 const struct sw_flow_key *key)
63 struct sw_flow *flow = *find_bucket(swt, key);
64 return flow && !flow_compare(&flow->key.flow, &key->flow) ? flow : NULL;
67 static int table_hash_insert(struct sw_table *swt, struct sw_flow *flow)
69 struct sw_table_hash *th = (struct sw_table_hash *) swt;
70 struct sw_flow **bucket;
73 if (flow->key.wildcards != 0)
76 bucket = find_bucket(swt, &flow->key);
77 if (*bucket == NULL) {
82 struct sw_flow *old_flow = *bucket;
83 if (!flow_compare(&old_flow->key.flow, &flow->key.flow)) {
94 /* Caller must update n_flows. */
96 do_delete(struct sw_flow **bucket)
102 /* Returns number of deleted flows. We can igonre the priority
103 * argument, since all exact-match entries are the same (highest)
105 static int table_hash_delete(struct sw_table *swt,
106 const struct sw_flow_key *key,
107 uint16_t priority, int strict)
109 struct sw_table_hash *th = (struct sw_table_hash *) swt;
110 unsigned int count = 0;
112 if (key->wildcards == 0) {
113 struct sw_flow **bucket = find_bucket(swt, key);
114 struct sw_flow *flow = *bucket;
115 if (flow && !flow_compare(&flow->key.flow, &key->flow)) {
122 for (i = 0; i <= th->bucket_mask; i++) {
123 struct sw_flow **bucket = &th->buckets[i];
124 struct sw_flow *flow = *bucket;
125 if (flow && flow_del_matches(&flow->key, key, strict)) {
131 th->n_flows -= count;
135 static void table_hash_timeout(struct sw_table *swt, struct list *deleted)
137 struct sw_table_hash *th = (struct sw_table_hash *) swt;
140 for (i = 0; i <= th->bucket_mask; i++) {
141 struct sw_flow **bucket = &th->buckets[i];
142 struct sw_flow *flow = *bucket;
143 if (flow && flow_timeout(flow)) {
144 list_push_back(deleted, &flow->node);
151 static void table_hash_destroy(struct sw_table *swt)
153 struct sw_table_hash *th = (struct sw_table_hash *) swt;
155 for (i = 0; i <= th->bucket_mask; i++) {
156 if (th->buckets[i]) {
157 flow_free(th->buckets[i]);
164 static int table_hash_iterate(struct sw_table *swt,
165 const struct sw_flow_key *key,
166 struct sw_table_position *position,
167 int (*callback)(struct sw_flow *, void *private),
170 struct sw_table_hash *th = (struct sw_table_hash *) swt;
172 if (position->private[0] > th->bucket_mask)
175 if (key->wildcards == 0) {
176 struct sw_flow *flow = table_hash_lookup(swt, key);
177 position->private[0] = -1;
178 return flow ? callback(flow, private) : 0;
182 for (i = position->private[0]; i <= th->bucket_mask; i++) {
183 struct sw_flow *flow = th->buckets[i];
184 if (flow && flow_matches_1wild(&flow->key, key)) {
185 int error = callback(flow, private);
187 position->private[0] = i + 1;
196 static void table_hash_stats(struct sw_table *swt,
197 struct sw_table_stats *stats)
199 struct sw_table_hash *th = (struct sw_table_hash *) swt;
200 stats->name = "hash";
201 stats->n_flows = th->n_flows;
202 stats->max_flows = th->bucket_mask + 1;
203 stats->n_matched = swt->n_matched;
206 struct sw_table *table_hash_create(unsigned int polynomial,
207 unsigned int n_buckets)
209 struct sw_table_hash *th;
210 struct sw_table *swt;
212 th = malloc(sizeof *th);
215 memset(th, '\0', sizeof *th);
217 assert(!(n_buckets & (n_buckets - 1)));
218 th->buckets = calloc(n_buckets, sizeof *th->buckets);
219 if (th->buckets == NULL) {
220 printf("failed to allocate %u buckets\n", n_buckets);
225 th->bucket_mask = n_buckets - 1;
228 swt->lookup = table_hash_lookup;
229 swt->insert = table_hash_insert;
230 swt->delete = table_hash_delete;
231 swt->timeout = table_hash_timeout;
232 swt->destroy = table_hash_destroy;
233 swt->iterate = table_hash_iterate;
234 swt->stats = table_hash_stats;
236 crc32_init(&th->crc32, polynomial);
241 /* Double-hashing table. */
243 struct sw_table_hash2 {
245 struct sw_table *subtable[2];
248 static struct sw_flow *table_hash2_lookup(struct sw_table *swt,
249 const struct sw_flow_key *key)
251 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
254 for (i = 0; i < 2; i++) {
255 struct sw_flow *flow = *find_bucket(t2->subtable[i], key);
256 if (flow && !flow_compare(&flow->key.flow, &key->flow))
262 static int table_hash2_insert(struct sw_table *swt, struct sw_flow *flow)
264 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
266 if (table_hash_insert(t2->subtable[0], flow))
268 return table_hash_insert(t2->subtable[1], flow);
271 static int table_hash2_delete(struct sw_table *swt,
272 const struct sw_flow_key *key,
273 uint16_t priority, int strict)
275 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
276 return (table_hash_delete(t2->subtable[0], key, priority, strict)
277 + table_hash_delete(t2->subtable[1], key, priority, strict));
280 static void table_hash2_timeout(struct sw_table *swt, struct list *deleted)
282 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
283 table_hash_timeout(t2->subtable[0], deleted);
284 table_hash_timeout(t2->subtable[1], deleted);
287 static void table_hash2_destroy(struct sw_table *swt)
289 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
290 table_hash_destroy(t2->subtable[0]);
291 table_hash_destroy(t2->subtable[1]);
295 static int table_hash2_iterate(struct sw_table *swt,
296 const struct sw_flow_key *key,
297 struct sw_table_position *position,
298 int (*callback)(struct sw_flow *, void *),
301 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
304 for (i = position->private[1]; i < 2; i++) {
305 int error = table_hash_iterate(t2->subtable[i], key, position,
310 position->private[0] = 0;
311 position->private[1]++;
316 static void table_hash2_stats(struct sw_table *swt,
317 struct sw_table_stats *stats)
319 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
320 struct sw_table_stats substats[2];
323 for (i = 0; i < 2; i++)
324 table_hash_stats(t2->subtable[i], &substats[i]);
325 stats->name = "hash2";
326 stats->n_flows = substats[0].n_flows + substats[1].n_flows;
327 stats->max_flows = substats[0].max_flows + substats[1].max_flows;
328 stats->n_matched = swt->n_matched;
331 struct sw_table *table_hash2_create(unsigned int poly0, unsigned int buckets0,
332 unsigned int poly1, unsigned int buckets1)
335 struct sw_table_hash2 *t2;
336 struct sw_table *swt;
338 t2 = malloc(sizeof *t2);
341 memset(t2, '\0', sizeof *t2);
343 t2->subtable[0] = table_hash_create(poly0, buckets0);
344 if (t2->subtable[0] == NULL)
347 t2->subtable[1] = table_hash_create(poly1, buckets1);
348 if (t2->subtable[1] == NULL)
349 goto out_free_subtable0;
352 swt->lookup = table_hash2_lookup;
353 swt->insert = table_hash2_insert;
354 swt->delete = table_hash2_delete;
355 swt->timeout = table_hash2_timeout;
356 swt->destroy = table_hash2_destroy;
357 swt->iterate = table_hash2_iterate;
358 swt->stats = table_hash2_stats;
363 table_hash_destroy(t2->subtable[0]);