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)) {
85 /* Keep stats from the original flow */
86 flow->used = old_flow->used;
87 flow->created = old_flow->created;
88 flow->packet_count = old_flow->packet_count;
89 flow->byte_count = old_flow->byte_count;
101 /* Caller must update n_flows. */
103 do_delete(struct sw_flow **bucket)
109 /* Returns number of deleted flows. We can igonre the priority
110 * argument, since all exact-match entries are the same (highest)
112 static int table_hash_delete(struct sw_table *swt,
113 const struct sw_flow_key *key,
114 uint16_t priority, int strict)
116 struct sw_table_hash *th = (struct sw_table_hash *) swt;
117 unsigned int count = 0;
119 if (key->wildcards == 0) {
120 struct sw_flow **bucket = find_bucket(swt, key);
121 struct sw_flow *flow = *bucket;
122 if (flow && !flow_compare(&flow->key.flow, &key->flow)) {
129 for (i = 0; i <= th->bucket_mask; i++) {
130 struct sw_flow **bucket = &th->buckets[i];
131 struct sw_flow *flow = *bucket;
132 if (flow && flow_del_matches(&flow->key, key, strict)) {
138 th->n_flows -= count;
142 static void table_hash_timeout(struct sw_table *swt, struct list *deleted)
144 struct sw_table_hash *th = (struct sw_table_hash *) swt;
147 for (i = 0; i <= th->bucket_mask; i++) {
148 struct sw_flow **bucket = &th->buckets[i];
149 struct sw_flow *flow = *bucket;
150 if (flow && flow_timeout(flow)) {
151 list_push_back(deleted, &flow->node);
158 static void table_hash_destroy(struct sw_table *swt)
160 struct sw_table_hash *th = (struct sw_table_hash *) swt;
162 for (i = 0; i <= th->bucket_mask; i++) {
163 if (th->buckets[i]) {
164 flow_free(th->buckets[i]);
171 static int table_hash_iterate(struct sw_table *swt,
172 const struct sw_flow_key *key,
173 struct sw_table_position *position,
174 int (*callback)(struct sw_flow *, void *private),
177 struct sw_table_hash *th = (struct sw_table_hash *) swt;
179 if (position->private[0] > th->bucket_mask)
182 if (key->wildcards == 0) {
183 struct sw_flow *flow = table_hash_lookup(swt, key);
184 position->private[0] = -1;
185 return flow ? callback(flow, private) : 0;
189 for (i = position->private[0]; i <= th->bucket_mask; i++) {
190 struct sw_flow *flow = th->buckets[i];
191 if (flow && flow_matches_1wild(&flow->key, key)) {
192 int error = callback(flow, private);
194 position->private[0] = i + 1;
203 static void table_hash_stats(struct sw_table *swt,
204 struct sw_table_stats *stats)
206 struct sw_table_hash *th = (struct sw_table_hash *) swt;
207 stats->name = "hash";
208 stats->wildcards = 0; /* No wildcards are supported. */
209 stats->n_flows = th->n_flows;
210 stats->max_flows = th->bucket_mask + 1;
211 stats->n_matched = swt->n_matched;
214 struct sw_table *table_hash_create(unsigned int polynomial,
215 unsigned int n_buckets)
217 struct sw_table_hash *th;
218 struct sw_table *swt;
220 th = malloc(sizeof *th);
223 memset(th, '\0', sizeof *th);
225 assert(!(n_buckets & (n_buckets - 1)));
226 th->buckets = calloc(n_buckets, sizeof *th->buckets);
227 if (th->buckets == NULL) {
228 printf("failed to allocate %u buckets\n", n_buckets);
233 th->bucket_mask = n_buckets - 1;
236 swt->lookup = table_hash_lookup;
237 swt->insert = table_hash_insert;
238 swt->delete = table_hash_delete;
239 swt->timeout = table_hash_timeout;
240 swt->destroy = table_hash_destroy;
241 swt->iterate = table_hash_iterate;
242 swt->stats = table_hash_stats;
244 crc32_init(&th->crc32, polynomial);
249 /* Double-hashing table. */
251 struct sw_table_hash2 {
253 struct sw_table *subtable[2];
256 static struct sw_flow *table_hash2_lookup(struct sw_table *swt,
257 const struct sw_flow_key *key)
259 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
262 for (i = 0; i < 2; i++) {
263 struct sw_flow *flow = *find_bucket(t2->subtable[i], key);
264 if (flow && !flow_compare(&flow->key.flow, &key->flow))
270 static int table_hash2_insert(struct sw_table *swt, struct sw_flow *flow)
272 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
274 if (table_hash_insert(t2->subtable[0], flow))
276 return table_hash_insert(t2->subtable[1], flow);
279 static int table_hash2_delete(struct sw_table *swt,
280 const struct sw_flow_key *key,
281 uint16_t priority, int strict)
283 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
284 return (table_hash_delete(t2->subtable[0], key, priority, strict)
285 + table_hash_delete(t2->subtable[1], key, priority, strict));
288 static void table_hash2_timeout(struct sw_table *swt, struct list *deleted)
290 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
291 table_hash_timeout(t2->subtable[0], deleted);
292 table_hash_timeout(t2->subtable[1], deleted);
295 static void table_hash2_destroy(struct sw_table *swt)
297 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
298 table_hash_destroy(t2->subtable[0]);
299 table_hash_destroy(t2->subtable[1]);
303 static int table_hash2_iterate(struct sw_table *swt,
304 const struct sw_flow_key *key,
305 struct sw_table_position *position,
306 int (*callback)(struct sw_flow *, void *),
309 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
312 for (i = position->private[1]; i < 2; i++) {
313 int error = table_hash_iterate(t2->subtable[i], key, position,
318 position->private[0] = 0;
319 position->private[1]++;
324 static void table_hash2_stats(struct sw_table *swt,
325 struct sw_table_stats *stats)
327 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
328 struct sw_table_stats substats[2];
331 for (i = 0; i < 2; i++)
332 table_hash_stats(t2->subtable[i], &substats[i]);
333 stats->name = "hash2";
334 stats->wildcards = 0; /* No wildcards are supported. */
335 stats->n_flows = substats[0].n_flows + substats[1].n_flows;
336 stats->max_flows = substats[0].max_flows + substats[1].max_flows;
337 stats->n_matched = swt->n_matched;
340 struct sw_table *table_hash2_create(unsigned int poly0, unsigned int buckets0,
341 unsigned int poly1, unsigned int buckets1)
344 struct sw_table_hash2 *t2;
345 struct sw_table *swt;
347 t2 = malloc(sizeof *t2);
350 memset(t2, '\0', sizeof *t2);
352 t2->subtable[0] = table_hash_create(poly0, buckets0);
353 if (t2->subtable[0] == NULL)
356 t2->subtable[1] = table_hash_create(poly1, buckets1);
357 if (t2->subtable[1] == NULL)
358 goto out_free_subtable0;
361 swt->lookup = table_hash2_lookup;
362 swt->insert = table_hash2_insert;
363 swt->delete = table_hash2_delete;
364 swt->timeout = table_hash2_timeout;
365 swt->destroy = table_hash2_destroy;
366 swt->iterate = table_hash2_iterate;
367 swt->stats = table_hash2_stats;
372 table_hash_destroy(t2->subtable[0]);