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.
42 #include "switch-flow.h"
44 struct sw_table_hash {
48 unsigned int bucket_mask; /* Number of buckets minus 1. */
49 struct sw_flow **buckets;
52 static struct sw_flow **find_bucket(struct sw_table *swt,
53 const struct sw_flow_key *key)
55 struct sw_table_hash *th = (struct sw_table_hash *) swt;
56 unsigned int crc = crc32_calculate(&th->crc32, key,
57 offsetof(struct sw_flow_key, wildcards));
58 return &th->buckets[crc & th->bucket_mask];
61 static struct sw_flow *table_hash_lookup(struct sw_table *swt,
62 const struct sw_flow_key *key)
64 struct sw_flow *flow = *find_bucket(swt, key);
65 return flow && !flow_compare(&flow->key.flow, &key->flow) ? flow : NULL;
68 static int table_hash_insert(struct sw_table *swt, struct sw_flow *flow)
70 struct sw_table_hash *th = (struct sw_table_hash *) swt;
71 struct sw_flow **bucket;
74 if (flow->key.wildcards != 0)
77 bucket = find_bucket(swt, &flow->key);
78 if (*bucket == NULL) {
83 struct sw_flow *old_flow = *bucket;
84 if (!flow_compare(&old_flow->key.flow, &flow->key.flow)) {
95 /* Caller must update n_flows. */
97 do_delete(struct sw_flow **bucket)
103 /* Returns number of deleted flows. We can igonre the priority
104 * argument, since all exact-match entries are the same (highest)
106 static int table_hash_delete(struct sw_table *swt,
107 const struct sw_flow_key *key,
108 uint16_t priority, int strict)
110 struct sw_table_hash *th = (struct sw_table_hash *) swt;
111 unsigned int count = 0;
113 if (key->wildcards == 0) {
114 struct sw_flow **bucket = find_bucket(swt, key);
115 struct sw_flow *flow = *bucket;
116 if (flow && !flow_compare(&flow->key.flow, &key->flow)) {
123 for (i = 0; i <= th->bucket_mask; i++) {
124 struct sw_flow **bucket = &th->buckets[i];
125 struct sw_flow *flow = *bucket;
126 if (flow && flow_del_matches(&flow->key, key, strict)) {
132 th->n_flows -= count;
136 static void table_hash_timeout(struct sw_table *swt, struct list *deleted)
138 struct sw_table_hash *th = (struct sw_table_hash *) swt;
141 for (i = 0; i <= th->bucket_mask; i++) {
142 struct sw_flow **bucket = &th->buckets[i];
143 struct sw_flow *flow = *bucket;
144 if (flow && flow_timeout(flow)) {
145 list_push_back(deleted, &flow->node);
152 static void table_hash_destroy(struct sw_table *swt)
154 struct sw_table_hash *th = (struct sw_table_hash *) swt;
156 for (i = 0; i <= th->bucket_mask; i++) {
157 if (th->buckets[i]) {
158 flow_free(th->buckets[i]);
165 static int table_hash_iterate(struct sw_table *swt,
166 const struct sw_flow_key *key,
167 struct sw_table_position *position,
168 int (*callback)(struct sw_flow *, void *private),
171 struct sw_table_hash *th = (struct sw_table_hash *) swt;
173 if (position->private[0] > th->bucket_mask)
176 if (key->wildcards == 0) {
177 struct sw_flow *flow = table_hash_lookup(swt, key);
178 position->private[0] = -1;
179 return flow ? callback(flow, private) : 0;
183 for (i = position->private[0]; i <= th->bucket_mask; i++) {
184 struct sw_flow *flow = th->buckets[i];
185 if (flow && flow_matches_1wild(&flow->key, key)) {
186 int error = callback(flow, private);
188 position->private[0] = i + 1;
197 static void table_hash_stats(struct sw_table *swt,
198 struct sw_table_stats *stats)
200 struct sw_table_hash *th = (struct sw_table_hash *) swt;
201 stats->name = "hash";
202 stats->n_flows = th->n_flows;
203 stats->max_flows = th->bucket_mask + 1;
204 stats->n_matched = swt->n_matched;
207 struct sw_table *table_hash_create(unsigned int polynomial,
208 unsigned int n_buckets)
210 struct sw_table_hash *th;
211 struct sw_table *swt;
213 th = malloc(sizeof *th);
216 memset(th, '\0', sizeof *th);
218 assert(!(n_buckets & (n_buckets - 1)));
219 th->buckets = calloc(n_buckets, sizeof *th->buckets);
220 if (th->buckets == NULL) {
221 printf("failed to allocate %u buckets\n", n_buckets);
226 th->bucket_mask = n_buckets - 1;
229 swt->lookup = table_hash_lookup;
230 swt->insert = table_hash_insert;
231 swt->delete = table_hash_delete;
232 swt->timeout = table_hash_timeout;
233 swt->destroy = table_hash_destroy;
234 swt->iterate = table_hash_iterate;
235 swt->stats = table_hash_stats;
237 crc32_init(&th->crc32, polynomial);
242 /* Double-hashing table. */
244 struct sw_table_hash2 {
246 struct sw_table *subtable[2];
249 static struct sw_flow *table_hash2_lookup(struct sw_table *swt,
250 const struct sw_flow_key *key)
252 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
255 for (i = 0; i < 2; i++) {
256 struct sw_flow *flow = *find_bucket(t2->subtable[i], key);
257 if (flow && !flow_compare(&flow->key.flow, &key->flow))
263 static int table_hash2_insert(struct sw_table *swt, struct sw_flow *flow)
265 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
267 if (table_hash_insert(t2->subtable[0], flow))
269 return table_hash_insert(t2->subtable[1], flow);
272 static int table_hash2_delete(struct sw_table *swt,
273 const struct sw_flow_key *key,
274 uint16_t priority, int strict)
276 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
277 return (table_hash_delete(t2->subtable[0], key, priority, strict)
278 + table_hash_delete(t2->subtable[1], key, priority, strict));
281 static void table_hash2_timeout(struct sw_table *swt, struct list *deleted)
283 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
284 table_hash_timeout(t2->subtable[0], deleted);
285 table_hash_timeout(t2->subtable[1], deleted);
288 static void table_hash2_destroy(struct sw_table *swt)
290 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
291 table_hash_destroy(t2->subtable[0]);
292 table_hash_destroy(t2->subtable[1]);
296 static int table_hash2_iterate(struct sw_table *swt,
297 const struct sw_flow_key *key,
298 struct sw_table_position *position,
299 int (*callback)(struct sw_flow *, void *),
302 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
305 for (i = position->private[1]; i < 2; i++) {
306 int error = table_hash_iterate(t2->subtable[i], key, position,
311 position->private[0] = 0;
312 position->private[1]++;
317 static void table_hash2_stats(struct sw_table *swt,
318 struct sw_table_stats *stats)
320 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
321 struct sw_table_stats substats[2];
324 for (i = 0; i < 2; i++)
325 table_hash_stats(t2->subtable[i], &substats[i]);
326 stats->name = "hash2";
327 stats->n_flows = substats[0].n_flows + substats[1].n_flows;
328 stats->max_flows = substats[0].max_flows + substats[1].max_flows;
329 stats->n_matched = swt->n_matched;
332 struct sw_table *table_hash2_create(unsigned int poly0, unsigned int buckets0,
333 unsigned int poly1, unsigned int buckets1)
336 struct sw_table_hash2 *t2;
337 struct sw_table *swt;
339 t2 = malloc(sizeof *t2);
342 memset(t2, '\0', sizeof *t2);
344 t2->subtable[0] = table_hash_create(poly0, buckets0);
345 if (t2->subtable[0] == NULL)
348 t2->subtable[1] = table_hash_create(poly1, buckets1);
349 if (t2->subtable[1] == NULL)
350 goto out_free_subtable0;
353 swt->lookup = table_hash2_lookup;
354 swt->insert = table_hash2_insert;
355 swt->delete = table_hash2_delete;
356 swt->timeout = table_hash2_timeout;
357 swt->destroy = table_hash2_destroy;
358 swt->iterate = table_hash2_iterate;
359 swt->stats = table_hash2_stats;
364 table_hash_destroy(t2->subtable[0]);