1 /* SPDX-License-Identifier: BSD-3-Clause
3 * Copyright (c) 2010-2015 Intel Corporation
4 * Copyright (c) 2007,2008 Kip Macy kmacy@freebsd.org
6 * Derived from FreeBSD's bufring.h
7 * Used as BSD-3 Licensed with permission from Kip Macy.
15 #include <sys/queue.h>
17 #include <rte_common.h>
19 #include <rte_memzone.h>
20 #include <rte_malloc.h>
21 #include <rte_eal_memconfig.h>
22 #include <rte_errno.h>
23 #include <rte_string_fns.h>
24 #include <rte_tailq.h>
27 #include "rte_ring_elem.h"
29 TAILQ_HEAD(rte_ring_list, rte_tailq_entry);
31 static struct rte_tailq_elem rte_ring_tailq = {
32 .name = RTE_TAILQ_RING_NAME,
34 EAL_REGISTER_TAILQ(rte_ring_tailq)
36 /* mask of all valid flag values to ring_create() */
37 #define RING_F_MASK (RING_F_SP_ENQ | RING_F_SC_DEQ | RING_F_EXACT_SZ | \
38 RING_F_MP_RTS_ENQ | RING_F_MC_RTS_DEQ | \
39 RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ)
41 /* true if x is a power of 2 */
42 #define POWEROF2(x) ((((x)-1) & (x)) == 0)
44 /* by default set head/tail distance as 1/8 of ring capacity */
47 /* return the size of memory occupied by a ring */
49 rte_ring_get_memsize_elem(unsigned int esize, unsigned int count)
53 /* Check if element size is a multiple of 4B */
55 RTE_LOG(ERR, RING, "element size is not a multiple of 4\n");
60 /* count must be a power of 2 */
61 if ((!POWEROF2(count)) || (count > RTE_RING_SZ_MASK )) {
63 "Requested number of elements is invalid, must be power of 2, and not exceed %u\n",
69 sz = sizeof(struct rte_ring) + (ssize_t)count * esize;
70 sz = RTE_ALIGN(sz, RTE_CACHE_LINE_SIZE);
74 /* return the size of memory occupied by a ring */
76 rte_ring_get_memsize(unsigned int count)
78 return rte_ring_get_memsize_elem(sizeof(void *), count);
82 * internal helper function to reset prod/cons head-tail values.
85 reset_headtail(void *p)
87 struct rte_ring_headtail *ht;
88 struct rte_ring_hts_headtail *ht_hts;
89 struct rte_ring_rts_headtail *ht_rts;
95 switch (ht->sync_type) {
96 case RTE_RING_SYNC_MT:
97 case RTE_RING_SYNC_ST:
101 case RTE_RING_SYNC_MT_RTS:
102 ht_rts->head.raw = 0;
103 ht_rts->tail.raw = 0;
105 case RTE_RING_SYNC_MT_HTS:
109 /* unknown sync mode */
115 rte_ring_reset(struct rte_ring *r)
117 reset_headtail(&r->prod);
118 reset_headtail(&r->cons);
122 * helper function, calculates sync_type values for prod and cons
123 * based on input flags. Returns zero at success or negative
124 * errno value otherwise.
127 get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
128 enum rte_ring_sync_type *cons_st)
130 static const uint32_t prod_st_flags =
131 (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ);
132 static const uint32_t cons_st_flags =
133 (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ);
135 switch (flags & prod_st_flags) {
137 *prod_st = RTE_RING_SYNC_MT;
140 *prod_st = RTE_RING_SYNC_ST;
142 case RING_F_MP_RTS_ENQ:
143 *prod_st = RTE_RING_SYNC_MT_RTS;
145 case RING_F_MP_HTS_ENQ:
146 *prod_st = RTE_RING_SYNC_MT_HTS;
152 switch (flags & cons_st_flags) {
154 *cons_st = RTE_RING_SYNC_MT;
157 *cons_st = RTE_RING_SYNC_ST;
159 case RING_F_MC_RTS_DEQ:
160 *cons_st = RTE_RING_SYNC_MT_RTS;
162 case RING_F_MC_HTS_DEQ:
163 *cons_st = RTE_RING_SYNC_MT_HTS;
173 rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
178 /* compilation-time checks */
179 RTE_BUILD_BUG_ON((sizeof(struct rte_ring) &
180 RTE_CACHE_LINE_MASK) != 0);
181 RTE_BUILD_BUG_ON((offsetof(struct rte_ring, cons) &
182 RTE_CACHE_LINE_MASK) != 0);
183 RTE_BUILD_BUG_ON((offsetof(struct rte_ring, prod) &
184 RTE_CACHE_LINE_MASK) != 0);
186 RTE_BUILD_BUG_ON(offsetof(struct rte_ring_headtail, sync_type) !=
187 offsetof(struct rte_ring_hts_headtail, sync_type));
188 RTE_BUILD_BUG_ON(offsetof(struct rte_ring_headtail, tail) !=
189 offsetof(struct rte_ring_hts_headtail, ht.pos.tail));
191 RTE_BUILD_BUG_ON(offsetof(struct rte_ring_headtail, sync_type) !=
192 offsetof(struct rte_ring_rts_headtail, sync_type));
193 RTE_BUILD_BUG_ON(offsetof(struct rte_ring_headtail, tail) !=
194 offsetof(struct rte_ring_rts_headtail, tail.val.pos));
196 /* future proof flags, only allow supported values */
197 if (flags & ~RING_F_MASK) {
199 "Unsupported flags requested %#x\n", flags);
203 /* init the ring structure */
204 memset(r, 0, sizeof(*r));
205 ret = strlcpy(r->name, name, sizeof(r->name));
206 if (ret < 0 || ret >= (int)sizeof(r->name))
207 return -ENAMETOOLONG;
209 ret = get_sync_type(flags, &r->prod.sync_type, &r->cons.sync_type);
213 if (flags & RING_F_EXACT_SZ) {
214 r->size = rte_align32pow2(count + 1);
215 r->mask = r->size - 1;
218 if ((!POWEROF2(count)) || (count > RTE_RING_SZ_MASK)) {
220 "Requested size is invalid, must be power of 2, and not exceed the size limit %u\n",
226 r->capacity = r->mask;
229 /* set default values for head-tail distance */
230 if (flags & RING_F_MP_RTS_ENQ)
231 rte_ring_set_prod_htd_max(r, r->capacity / HTD_MAX_DEF);
232 if (flags & RING_F_MC_RTS_DEQ)
233 rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
238 /* create the ring for a given element size */
240 rte_ring_create_elem(const char *name, unsigned int esize, unsigned int count,
241 int socket_id, unsigned int flags)
243 char mz_name[RTE_MEMZONE_NAMESIZE];
245 struct rte_tailq_entry *te;
246 const struct rte_memzone *mz;
249 struct rte_ring_list* ring_list = NULL;
250 const unsigned int requested_count = count;
253 ring_list = RTE_TAILQ_CAST(rte_ring_tailq.head, rte_ring_list);
255 /* for an exact size ring, round up from count to a power of two */
256 if (flags & RING_F_EXACT_SZ)
257 count = rte_align32pow2(count + 1);
259 ring_size = rte_ring_get_memsize_elem(esize, count);
261 rte_errno = -ring_size;
265 ret = snprintf(mz_name, sizeof(mz_name), "%s%s",
266 RTE_RING_MZ_PREFIX, name);
267 if (ret < 0 || ret >= (int)sizeof(mz_name)) {
268 rte_errno = ENAMETOOLONG;
272 te = rte_zmalloc("RING_TAILQ_ENTRY", sizeof(*te), 0);
274 RTE_LOG(ERR, RING, "Cannot reserve memory for tailq\n");
279 rte_mcfg_tailq_write_lock();
281 /* reserve a memory zone for this ring. If we can't get rte_config or
282 * we are secondary process, the memzone_reserve function will set
283 * rte_errno for us appropriately - hence no check in this this function */
284 mz = rte_memzone_reserve_aligned(mz_name, ring_size, socket_id,
285 mz_flags, __alignof__(*r));
288 /* no need to check return value here, we already checked the
290 rte_ring_init(r, name, requested_count, flags);
292 te->data = (void *) r;
295 TAILQ_INSERT_TAIL(ring_list, te, next);
298 RTE_LOG(ERR, RING, "Cannot reserve memory\n");
301 rte_mcfg_tailq_write_unlock();
306 /* create the ring */
308 rte_ring_create(const char *name, unsigned int count, int socket_id,
311 return rte_ring_create_elem(name, sizeof(void *), count, socket_id,
317 rte_ring_free(struct rte_ring *r)
319 struct rte_ring_list *ring_list = NULL;
320 struct rte_tailq_entry *te;
326 * Ring was not created with rte_ring_create,
327 * therefore, there is no memzone to free.
329 if (r->memzone == NULL) {
331 "Cannot free ring, not created with rte_ring_create()\n");
335 if (rte_memzone_free(r->memzone) != 0) {
336 RTE_LOG(ERR, RING, "Cannot free memory\n");
340 ring_list = RTE_TAILQ_CAST(rte_ring_tailq.head, rte_ring_list);
341 rte_mcfg_tailq_write_lock();
343 /* find out tailq entry */
344 TAILQ_FOREACH(te, ring_list, next) {
345 if (te->data == (void *) r)
350 rte_mcfg_tailq_write_unlock();
354 TAILQ_REMOVE(ring_list, te, next);
356 rte_mcfg_tailq_write_unlock();
361 /* dump the status of the ring on the console */
363 rte_ring_dump(FILE *f, const struct rte_ring *r)
365 fprintf(f, "ring <%s>@%p\n", r->name, r);
366 fprintf(f, " flags=%x\n", r->flags);
367 fprintf(f, " size=%"PRIu32"\n", r->size);
368 fprintf(f, " capacity=%"PRIu32"\n", r->capacity);
369 fprintf(f, " ct=%"PRIu32"\n", r->cons.tail);
370 fprintf(f, " ch=%"PRIu32"\n", r->cons.head);
371 fprintf(f, " pt=%"PRIu32"\n", r->prod.tail);
372 fprintf(f, " ph=%"PRIu32"\n", r->prod.head);
373 fprintf(f, " used=%u\n", rte_ring_count(r));
374 fprintf(f, " avail=%u\n", rte_ring_free_count(r));
377 /* dump the status of all rings on the console */
379 rte_ring_list_dump(FILE *f)
381 const struct rte_tailq_entry *te;
382 struct rte_ring_list *ring_list;
384 ring_list = RTE_TAILQ_CAST(rte_ring_tailq.head, rte_ring_list);
386 rte_mcfg_tailq_read_lock();
388 TAILQ_FOREACH(te, ring_list, next) {
389 rte_ring_dump(f, (struct rte_ring *) te->data);
392 rte_mcfg_tailq_read_unlock();
395 /* search a ring from its name */
397 rte_ring_lookup(const char *name)
399 struct rte_tailq_entry *te;
400 struct rte_ring *r = NULL;
401 struct rte_ring_list *ring_list;
403 ring_list = RTE_TAILQ_CAST(rte_ring_tailq.head, rte_ring_list);
405 rte_mcfg_tailq_read_lock();
407 TAILQ_FOREACH(te, ring_list, next) {
408 r = (struct rte_ring *) te->data;
409 if (strncmp(name, r->name, RTE_RING_NAMESIZE) == 0)
413 rte_mcfg_tailq_read_unlock();