1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
3 */
4
5 #include <stdalign.h>
6 #include <string.h>
7 #include <sys/queue.h>
8
9 #include <rte_string_fns.h>
10 #include <rte_log.h>
11 #include <rte_mbuf.h>
12 #include <rte_mbuf_dyn.h>
13 #include <rte_eal_memconfig.h>
14 #include <rte_errno.h>
15 #include <rte_malloc.h>
16 #include <rte_tailq.h>
17
18 #include "rte_reorder.h"
19
20 RTE_LOG_REGISTER_DEFAULT(reorder_logtype, INFO);
21 #define RTE_LOGTYPE_REORDER reorder_logtype
22 #define REORDER_LOG(level, ...) \
23 RTE_LOG_LINE(level, REORDER, "" __VA_ARGS__)
24
25 TAILQ_HEAD(rte_reorder_list, rte_tailq_entry);
26
27 static struct rte_tailq_elem rte_reorder_tailq = {
28 .name = "RTE_REORDER",
29 };
30 EAL_REGISTER_TAILQ(rte_reorder_tailq)
31
32 #define NO_FLAGS 0
33 #define RTE_REORDER_PREFIX "RO_"
34 #define RTE_REORDER_NAMESIZE 32
35
36 #define RTE_REORDER_SEQN_DYNFIELD_NAME "rte_reorder_seqn_dynfield"
37 int rte_reorder_seqn_dynfield_offset = -1;
38
39 /* A generic circular buffer */
40 struct __rte_cache_aligned cir_buffer {
41 unsigned int size; /**< Number of entries that can be stored */
42 unsigned int mask; /**< [buffer_size - 1]: used for wrap-around */
43 unsigned int head; /**< insertion point in buffer */
44 unsigned int tail; /**< extraction point in buffer */
45 struct rte_mbuf **entries;
46 };
47
48 /* The reorder buffer data structure itself */
49 struct __rte_cache_aligned rte_reorder_buffer {
50 char name[RTE_REORDER_NAMESIZE];
51 uint32_t min_seqn; /**< Lowest seq. number that can be in the buffer */
52 unsigned int memsize; /**< memory area size of reorder buffer */
53 bool is_initialized; /**< flag indicates that buffer was initialized */
54
55 struct cir_buffer ready_buf; /**< temp buffer for dequeued entries */
56 struct cir_buffer order_buf; /**< buffer used to reorder entries */
57 };
58
59 static void
60 rte_reorder_free_mbufs(struct rte_reorder_buffer *b);
61
62 unsigned int
rte_reorder_memory_footprint_get(unsigned int size)63 rte_reorder_memory_footprint_get(unsigned int size)
64 {
65 return sizeof(struct rte_reorder_buffer) + (2 * size * sizeof(struct rte_mbuf *));
66 }
67
68 struct rte_reorder_buffer *
rte_reorder_init(struct rte_reorder_buffer * b,unsigned int bufsize,const char * name,unsigned int size)69 rte_reorder_init(struct rte_reorder_buffer *b, unsigned int bufsize,
70 const char *name, unsigned int size)
71 {
72 const unsigned int min_bufsize = rte_reorder_memory_footprint_get(size);
73 static const struct rte_mbuf_dynfield reorder_seqn_dynfield_desc = {
74 .name = RTE_REORDER_SEQN_DYNFIELD_NAME,
75 .size = sizeof(rte_reorder_seqn_t),
76 .align = alignof(rte_reorder_seqn_t),
77 };
78
79 if (b == NULL) {
80 REORDER_LOG(ERR, "Invalid reorder buffer parameter:"
81 " NULL");
82 rte_errno = EINVAL;
83 return NULL;
84 }
85 if (!rte_is_power_of_2(size)) {
86 REORDER_LOG(ERR, "Invalid reorder buffer size"
87 " - Not a power of 2");
88 rte_errno = EINVAL;
89 return NULL;
90 }
91 if (name == NULL) {
92 REORDER_LOG(ERR, "Invalid reorder buffer name ptr:"
93 " NULL");
94 rte_errno = EINVAL;
95 return NULL;
96 }
97 if (bufsize < min_bufsize) {
98 REORDER_LOG(ERR, "Invalid reorder buffer memory size: %u, "
99 "minimum required: %u", bufsize, min_bufsize);
100 rte_errno = EINVAL;
101 return NULL;
102 }
103
104 rte_reorder_seqn_dynfield_offset = rte_mbuf_dynfield_register(&reorder_seqn_dynfield_desc);
105 if (rte_reorder_seqn_dynfield_offset < 0) {
106 REORDER_LOG(ERR,
107 "Failed to register mbuf field for reorder sequence number, rte_errno: %i",
108 rte_errno);
109 rte_errno = ENOMEM;
110 return NULL;
111 }
112
113 memset(b, 0, bufsize);
114 strlcpy(b->name, name, sizeof(b->name));
115 b->memsize = bufsize;
116 b->order_buf.size = b->ready_buf.size = size;
117 b->order_buf.mask = b->ready_buf.mask = size - 1;
118 b->ready_buf.entries = (void *)&b[1];
119 b->order_buf.entries = RTE_PTR_ADD(&b[1],
120 size * sizeof(b->ready_buf.entries[0]));
121
122 return b;
123 }
124
125 /*
126 * Insert new entry into global list.
127 * Returns pointer to already inserted entry if such exists, or to newly inserted one.
128 */
129 static struct rte_tailq_entry *
rte_reorder_entry_insert(struct rte_tailq_entry * new_te)130 rte_reorder_entry_insert(struct rte_tailq_entry *new_te)
131 {
132 struct rte_reorder_list *reorder_list;
133 struct rte_reorder_buffer *b, *nb;
134 struct rte_tailq_entry *te;
135
136 rte_mcfg_tailq_write_lock();
137
138 reorder_list = RTE_TAILQ_CAST(rte_reorder_tailq.head, rte_reorder_list);
139 /* guarantee there's no existing */
140 TAILQ_FOREACH(te, reorder_list, next) {
141 b = (struct rte_reorder_buffer *) te->data;
142 nb = (struct rte_reorder_buffer *) new_te->data;
143 if (strncmp(nb->name, b->name, RTE_REORDER_NAMESIZE) == 0)
144 break;
145 }
146
147 if (te == NULL) {
148 TAILQ_INSERT_TAIL(reorder_list, new_te, next);
149 te = new_te;
150 }
151
152 rte_mcfg_tailq_write_unlock();
153
154 return te;
155 }
156
157 struct rte_reorder_buffer*
rte_reorder_create(const char * name,unsigned socket_id,unsigned int size)158 rte_reorder_create(const char *name, unsigned socket_id, unsigned int size)
159 {
160 struct rte_reorder_buffer *b = NULL;
161 struct rte_tailq_entry *te, *te_inserted;
162
163 const unsigned int bufsize = rte_reorder_memory_footprint_get(size);
164
165 /* Check user arguments. */
166 if (!rte_is_power_of_2(size)) {
167 REORDER_LOG(ERR, "Invalid reorder buffer size"
168 " - Not a power of 2");
169 rte_errno = EINVAL;
170 return NULL;
171 }
172 if (name == NULL) {
173 REORDER_LOG(ERR, "Invalid reorder buffer name ptr:"
174 " NULL");
175 rte_errno = EINVAL;
176 return NULL;
177 }
178
179 /* allocate tailq entry */
180 te = rte_zmalloc("REORDER_TAILQ_ENTRY", sizeof(*te), 0);
181 if (te == NULL) {
182 REORDER_LOG(ERR, "Failed to allocate tailq entry");
183 rte_errno = ENOMEM;
184 return NULL;
185 }
186
187 /* Allocate memory to store the reorder buffer structure. */
188 b = rte_zmalloc_socket("REORDER_BUFFER", bufsize, 0, socket_id);
189 if (b == NULL) {
190 REORDER_LOG(ERR, "Memzone allocation failed");
191 rte_errno = ENOMEM;
192 rte_free(te);
193 return NULL;
194 } else {
195 if (rte_reorder_init(b, bufsize, name, size) == NULL) {
196 rte_free(b);
197 rte_free(te);
198 return NULL;
199 }
200 te->data = (void *)b;
201 }
202
203 te_inserted = rte_reorder_entry_insert(te);
204 if (te_inserted != te) {
205 rte_free(b);
206 rte_free(te);
207 return te_inserted->data;
208 }
209
210 return b;
211 }
212
213 void
rte_reorder_reset(struct rte_reorder_buffer * b)214 rte_reorder_reset(struct rte_reorder_buffer *b)
215 {
216 char name[RTE_REORDER_NAMESIZE];
217
218 rte_reorder_free_mbufs(b);
219 strlcpy(name, b->name, sizeof(name));
220 /* No error checking as current values should be valid */
221 rte_reorder_init(b, b->memsize, name, b->order_buf.size);
222 }
223
224 static void
rte_reorder_free_mbufs(struct rte_reorder_buffer * b)225 rte_reorder_free_mbufs(struct rte_reorder_buffer *b)
226 {
227 unsigned i;
228
229 /* Free up the mbufs of order buffer & ready buffer */
230 for (i = 0; i < b->order_buf.size; i++) {
231 rte_pktmbuf_free(b->order_buf.entries[i]);
232 rte_pktmbuf_free(b->ready_buf.entries[i]);
233 }
234 }
235
236 void
rte_reorder_free(struct rte_reorder_buffer * b)237 rte_reorder_free(struct rte_reorder_buffer *b)
238 {
239 struct rte_reorder_list *reorder_list;
240 struct rte_tailq_entry *te;
241
242 /* Check user arguments. */
243 if (b == NULL)
244 return;
245
246 reorder_list = RTE_TAILQ_CAST(rte_reorder_tailq.head, rte_reorder_list);
247
248 rte_mcfg_tailq_write_lock();
249
250 /* find our tailq entry */
251 TAILQ_FOREACH(te, reorder_list, next) {
252 if (te->data == (void *) b)
253 break;
254 }
255 if (te == NULL) {
256 rte_mcfg_tailq_write_unlock();
257 return;
258 }
259
260 TAILQ_REMOVE(reorder_list, te, next);
261
262 rte_mcfg_tailq_write_unlock();
263
264 rte_reorder_free_mbufs(b);
265
266 rte_free(b);
267 rte_free(te);
268 }
269
270 struct rte_reorder_buffer *
rte_reorder_find_existing(const char * name)271 rte_reorder_find_existing(const char *name)
272 {
273 struct rte_reorder_buffer *b = NULL;
274 struct rte_tailq_entry *te;
275 struct rte_reorder_list *reorder_list;
276
277 if (name == NULL) {
278 rte_errno = EINVAL;
279 return NULL;
280 }
281
282 reorder_list = RTE_TAILQ_CAST(rte_reorder_tailq.head, rte_reorder_list);
283
284 rte_mcfg_tailq_read_lock();
285 TAILQ_FOREACH(te, reorder_list, next) {
286 b = (struct rte_reorder_buffer *) te->data;
287 if (strncmp(name, b->name, RTE_REORDER_NAMESIZE) == 0)
288 break;
289 }
290 rte_mcfg_tailq_read_unlock();
291
292 if (te == NULL) {
293 rte_errno = ENOENT;
294 return NULL;
295 }
296
297 return b;
298 }
299
300 static unsigned
rte_reorder_fill_overflow(struct rte_reorder_buffer * b,unsigned n)301 rte_reorder_fill_overflow(struct rte_reorder_buffer *b, unsigned n)
302 {
303 /*
304 * 1. Move all ready entries that fit to the ready_buf
305 * 2. check if we meet the minimum needed (n).
306 * 3. If not, then skip any gaps and keep moving.
307 * 4. If at any point the ready buffer is full, stop
308 * 5. Return the number of positions the order_buf head has moved
309 */
310
311 struct cir_buffer *order_buf = &b->order_buf,
312 *ready_buf = &b->ready_buf;
313
314 unsigned int order_head_adv = 0;
315
316 /*
317 * move at least n packets to ready buffer, assuming ready buffer
318 * has room for those packets.
319 */
320 while (order_head_adv < n &&
321 ((ready_buf->head + 1) & ready_buf->mask) != ready_buf->tail) {
322
323 /* if we are blocked waiting on a packet, skip it */
324 if (order_buf->entries[order_buf->head] == NULL) {
325 order_buf->head = (order_buf->head + 1) & order_buf->mask;
326 order_head_adv++;
327 }
328
329 /* Move all ready entries that fit to the ready_buf */
330 while (order_buf->entries[order_buf->head] != NULL) {
331 ready_buf->entries[ready_buf->head] =
332 order_buf->entries[order_buf->head];
333
334 order_buf->entries[order_buf->head] = NULL;
335 order_head_adv++;
336
337 order_buf->head = (order_buf->head + 1) & order_buf->mask;
338
339 if (((ready_buf->head + 1) & ready_buf->mask) == ready_buf->tail)
340 break;
341
342 ready_buf->head = (ready_buf->head + 1) & ready_buf->mask;
343 }
344 }
345
346 b->min_seqn += order_head_adv;
347 /* Return the number of positions the order_buf head has moved */
348 return order_head_adv;
349 }
350
351 int
rte_reorder_insert(struct rte_reorder_buffer * b,struct rte_mbuf * mbuf)352 rte_reorder_insert(struct rte_reorder_buffer *b, struct rte_mbuf *mbuf)
353 {
354 uint32_t offset, position;
355 struct cir_buffer *order_buf;
356
357 if (b == NULL || mbuf == NULL) {
358 rte_errno = EINVAL;
359 return -1;
360 }
361
362 order_buf = &b->order_buf;
363 if (!b->is_initialized) {
364 b->min_seqn = *rte_reorder_seqn(mbuf);
365 b->is_initialized = 1;
366 }
367
368 /*
369 * calculate the offset from the head pointer we need to go.
370 * The subtraction takes care of the sequence number wrapping.
371 * For example (using 16-bit for brevity):
372 * min_seqn = 0xFFFD
373 * mbuf_seqn = 0x0010
374 * offset = 0x0010 - 0xFFFD = 0x13
375 */
376 offset = *rte_reorder_seqn(mbuf) - b->min_seqn;
377
378 /*
379 * action to take depends on offset.
380 * offset < buffer->size: the mbuf fits within the current window of
381 * sequence numbers we can reorder. EXPECTED CASE.
382 * offset > buffer->size: the mbuf is outside the current window. There
383 * are a number of cases to consider:
384 * 1. The packet sequence is just outside the window, then we need
385 * to see about shifting the head pointer and taking any ready
386 * to return packets out of the ring. If there was a delayed
387 * or dropped packet preventing drains from shifting the window
388 * this case will skip over the dropped packet instead, and any
389 * packets dequeued here will be returned on the next drain call.
390 * 2. The packet sequence number is vastly outside our window, taken
391 * here as having offset greater than twice the buffer size. In
392 * this case, the packet is probably an old or late packet that
393 * was previously skipped, so just enqueue the packet for
394 * immediate return on the next drain call, or else return error.
395 */
396 if (offset < b->order_buf.size) {
397 position = (order_buf->head + offset) & order_buf->mask;
398 order_buf->entries[position] = mbuf;
399 } else if (offset < 2 * b->order_buf.size) {
400 if (rte_reorder_fill_overflow(b, offset + 1 - order_buf->size)
401 < (offset + 1 - order_buf->size)) {
402 /* Put in handling for enqueue straight to output */
403 rte_errno = ENOSPC;
404 return -1;
405 }
406 offset = *rte_reorder_seqn(mbuf) - b->min_seqn;
407 position = (order_buf->head + offset) & order_buf->mask;
408 order_buf->entries[position] = mbuf;
409 } else {
410 /* Put in handling for enqueue straight to output */
411 rte_errno = ERANGE;
412 return -1;
413 }
414 return 0;
415 }
416
417 unsigned int
rte_reorder_drain(struct rte_reorder_buffer * b,struct rte_mbuf ** mbufs,unsigned max_mbufs)418 rte_reorder_drain(struct rte_reorder_buffer *b, struct rte_mbuf **mbufs,
419 unsigned max_mbufs)
420 {
421 unsigned int drain_cnt = 0;
422
423 struct cir_buffer *order_buf = &b->order_buf,
424 *ready_buf = &b->ready_buf;
425
426 /* Try to fetch requested number of mbufs from ready buffer */
427 while ((drain_cnt < max_mbufs) && (ready_buf->tail != ready_buf->head)) {
428 mbufs[drain_cnt++] = ready_buf->entries[ready_buf->tail];
429 ready_buf->entries[ready_buf->tail] = NULL;
430 ready_buf->tail = (ready_buf->tail + 1) & ready_buf->mask;
431 }
432
433 /*
434 * If requested number of buffers not fetched from ready buffer, fetch
435 * remaining buffers from order buffer
436 */
437 while ((drain_cnt < max_mbufs) &&
438 (order_buf->entries[order_buf->head] != NULL)) {
439 mbufs[drain_cnt++] = order_buf->entries[order_buf->head];
440 order_buf->entries[order_buf->head] = NULL;
441 b->min_seqn++;
442 order_buf->head = (order_buf->head + 1) & order_buf->mask;
443 }
444
445 return drain_cnt;
446 }
447
448 /* Binary search seqn in ready buffer */
449 static inline uint32_t
ready_buffer_seqn_find(const struct cir_buffer * ready_buf,const uint32_t seqn)450 ready_buffer_seqn_find(const struct cir_buffer *ready_buf, const uint32_t seqn)
451 {
452 uint32_t mid, value, position, high;
453 uint32_t low = 0;
454
455 if (ready_buf->tail > ready_buf->head)
456 high = ready_buf->tail - ready_buf->head;
457 else
458 high = ready_buf->head - ready_buf->tail;
459
460 while (low <= high) {
461 mid = low + (high - low) / 2;
462 position = (ready_buf->tail + mid) & ready_buf->mask;
463 value = *rte_reorder_seqn(ready_buf->entries[position]);
464 if (seqn == value)
465 return mid;
466 else if (seqn > value)
467 low = mid + 1;
468 else
469 high = mid - 1;
470 }
471
472 return low;
473 }
474
475 unsigned int
rte_reorder_drain_up_to_seqn(struct rte_reorder_buffer * b,struct rte_mbuf ** mbufs,const unsigned int max_mbufs,const rte_reorder_seqn_t seqn)476 rte_reorder_drain_up_to_seqn(struct rte_reorder_buffer *b, struct rte_mbuf **mbufs,
477 const unsigned int max_mbufs, const rte_reorder_seqn_t seqn)
478 {
479 uint32_t i, position, offset;
480 unsigned int drain_cnt = 0;
481
482 struct cir_buffer *order_buf = &b->order_buf,
483 *ready_buf = &b->ready_buf;
484
485 /* Seqn in Ready buffer */
486 if (seqn < b->min_seqn) {
487 /* All sequence numbers are higher then given */
488 if ((ready_buf->tail == ready_buf->head) ||
489 (*rte_reorder_seqn(ready_buf->entries[ready_buf->tail]) > seqn))
490 return 0;
491
492 offset = ready_buffer_seqn_find(ready_buf, seqn);
493
494 for (i = 0; (i < offset) && (drain_cnt < max_mbufs); i++) {
495 position = (ready_buf->tail + i) & ready_buf->mask;
496 mbufs[drain_cnt++] = ready_buf->entries[position];
497 ready_buf->entries[position] = NULL;
498 }
499 ready_buf->tail = (ready_buf->tail + i) & ready_buf->mask;
500
501 return drain_cnt;
502 }
503
504 /* Seqn in Order buffer, add all buffers from Ready buffer */
505 while ((drain_cnt < max_mbufs) && (ready_buf->tail != ready_buf->head)) {
506 mbufs[drain_cnt++] = ready_buf->entries[ready_buf->tail];
507 ready_buf->entries[ready_buf->tail] = NULL;
508 ready_buf->tail = (ready_buf->tail + 1) & ready_buf->mask;
509 }
510
511 /* Fetch buffers from Order buffer up to given sequence number (exclusive) */
512 offset = RTE_MIN(seqn - b->min_seqn, b->order_buf.size);
513 for (i = 0; (i < offset) && (drain_cnt < max_mbufs); i++) {
514 position = (order_buf->head + i) & order_buf->mask;
515 if (order_buf->entries[position] == NULL)
516 continue;
517 mbufs[drain_cnt++] = order_buf->entries[position];
518 order_buf->entries[position] = NULL;
519 }
520 b->min_seqn += i;
521 order_buf->head = (order_buf->head + i) & order_buf->mask;
522
523 return drain_cnt;
524 }
525
526 static bool
rte_reorder_is_empty(const struct rte_reorder_buffer * b)527 rte_reorder_is_empty(const struct rte_reorder_buffer *b)
528 {
529 const struct cir_buffer *order_buf = &b->order_buf, *ready_buf = &b->ready_buf;
530 unsigned int i;
531
532 /* Ready buffer does not have gaps */
533 if (ready_buf->tail != ready_buf->head)
534 return false;
535
536 /* Order buffer could have gaps, iterate */
537 for (i = 0; i < order_buf->size; i++) {
538 if (order_buf->entries[i] != NULL)
539 return false;
540 }
541
542 return true;
543 }
544
545 unsigned int
rte_reorder_min_seqn_set(struct rte_reorder_buffer * b,rte_reorder_seqn_t min_seqn)546 rte_reorder_min_seqn_set(struct rte_reorder_buffer *b, rte_reorder_seqn_t min_seqn)
547 {
548 if (!rte_reorder_is_empty(b))
549 return -ENOTEMPTY;
550
551 b->min_seqn = min_seqn;
552 b->is_initialized = true;
553
554 return 0;
555 }
556