Line data Source code
1 : /*
2 : * Copyright (c) 2016-2019 Cisco and/or its affiliates.
3 : * Copyright (c) 2019 Arm Limited
4 : * Copyright (c) 2010-2017 Intel Corporation and/or its affiliates.
5 : * Copyright (c) 2007-2009 Kip Macy kmacy@freebsd.org
6 : * Inspired from DPDK rte_ring.h (SPSC only) (derived from freebsd bufring.h).
7 : * Licensed under the Apache License, Version 2.0 (the "License");
8 : * you may not use this file except in compliance with the License.
9 : * You may obtain a copy of the License at:
10 : *
11 : * http://www.apache.org/licenses/LICENSE-2.0
12 : *
13 : * Unless required by applicable law or agreed to in writing, software
14 : * distributed under the License is distributed on an "AS IS" BASIS,
15 : * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 : * See the License for the specific language governing permissions and
17 : * limitations under the License.
18 : */
19 : #ifndef __included_ssvm_fifo_h__
20 : #define __included_ssvm_fifo_h__
21 :
22 : #include <vppinfra/clib.h>
23 : #include <vppinfra/vec.h>
24 : #include <vppinfra/pool.h>
25 : #include <vppinfra/format.h>
26 : #include <svm/fifo_types.h>
27 :
28 : #define OOO_SEGMENT_INVALID_INDEX ((u32)~0)
29 : #define SVM_FIFO_INVALID_SESSION_INDEX ((u32)~0)
30 : #define SVM_FIFO_INVALID_INDEX ((u32)~0)
31 :
32 : typedef enum svm_fifo_deq_ntf_
33 : {
34 : SVM_FIFO_NO_DEQ_NOTIF = 0, /**< No notification requested */
35 : SVM_FIFO_WANT_DEQ_NOTIF = 1, /**< Notify on dequeue */
36 : SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL = 2, /**< Notify on transition from full */
37 : SVM_FIFO_WANT_DEQ_NOTIF_IF_EMPTY = 4, /**< Notify on transition to empty */
38 : } svm_fifo_deq_ntf_t;
39 :
40 : typedef enum svm_fifo_flag_
41 : {
42 : SVM_FIFO_F_LL_TRACKED = 1 << 0,
43 : } svm_fifo_flag_t;
44 :
45 : typedef enum
46 : {
47 : SVM_FIFO_EFULL = -2,
48 : SVM_FIFO_EEMPTY = -3,
49 : SVM_FIFO_EGROW = -4,
50 : } svm_fifo_err_t;
51 :
52 : typedef struct svm_fifo_seg_
53 : {
54 : u8 *data;
55 : u32 len;
56 : } svm_fifo_seg_t;
57 :
58 : #if SVM_FIFO_TRACE
59 : #define svm_fifo_trace_add(_f, _s, _l, _t) \
60 : { \
61 : svm_fifo_trace_elem_t *trace_elt; \
62 : vec_add2(_f->trace, trace_elt, 1); \
63 : trace_elt->offset = _s; \
64 : trace_elt->len = _l; \
65 : trace_elt->action = _t; \
66 : }
67 : #else
68 : #define svm_fifo_trace_add(_f, _s, _l, _t)
69 : #endif
70 :
71 : u8 *svm_fifo_dump_trace (u8 * s, svm_fifo_t * f);
72 : u8 *svm_fifo_replay (u8 * s, svm_fifo_t * f, u8 no_read, u8 verbose);
73 :
74 : /**
75 : * Load head and tail optimized for consumer
76 : *
77 : * Internal function.
78 : */
79 : static inline void
80 55600044 : f_load_head_tail_cons (svm_fifo_t * f, u32 * head, u32 * tail)
81 : {
82 : /* load-relaxed: consumer owned index */
83 55600044 : *head = f->shr->head;
84 : /* load-acq: consumer foreign index (paired with store-rel in producer) */
85 55600044 : *tail = clib_atomic_load_acq_n (&f->shr->tail);
86 55600044 : }
87 :
88 : /** Load head and tail optimized for producer
89 : *
90 : * Internal function
91 : */
92 : static inline void
93 14350013 : f_load_head_tail_prod (svm_fifo_t * f, u32 * head, u32 * tail)
94 : {
95 : /* load relaxed: producer owned index */
96 14350013 : *tail = f->shr->tail;
97 : /* load-acq: producer foreign index (paired with store-rel in consumer) */
98 14350013 : *head = clib_atomic_load_acq_n (&f->shr->head);
99 14350013 : }
100 :
101 : /**
102 : * Load head and tail independent of producer/consumer role
103 : *
104 : * Internal function.
105 : */
106 : static inline void
107 502051 : f_load_head_tail_all_acq (svm_fifo_t * f, u32 * head, u32 * tail)
108 : {
109 : /* load-acq : consumer foreign index (paired with store-rel) */
110 502051 : *tail = clib_atomic_load_acq_n (&f->shr->tail);
111 : /* load-acq : producer foriegn index (paired with store-rel) */
112 502051 : *head = clib_atomic_load_acq_n (&f->shr->head);
113 502051 : }
114 :
115 : /**
116 : * Fifo current size, i.e., number of bytes enqueued
117 : *
118 : * Internal function.
119 : */
120 : static inline u32
121 70482172 : f_cursize (svm_fifo_t * f, u32 head, u32 tail)
122 : {
123 70482172 : return tail - head;
124 : }
125 :
126 : /**
127 : * Fifo free bytes, i.e., number of free bytes
128 : *
129 : * Internal function
130 : */
131 : static inline u32
132 14466922 : f_free_count (svm_fifo_t * f, u32 head, u32 tail)
133 : {
134 14466922 : return (f->shr->size - f_cursize (f, head, tail));
135 : }
136 :
137 : always_inline u32
138 2603790 : f_chunk_end (svm_fifo_chunk_t * c)
139 : {
140 2603790 : return c->start_byte + c->length;
141 : }
142 :
143 : always_inline int
144 19266120 : f_pos_lt (u32 a, u32 b)
145 : {
146 19266120 : return ((i32) (a - b) < 0);
147 : }
148 :
149 : always_inline int
150 8272 : f_pos_leq (u32 a, u32 b)
151 : {
152 8272 : return ((i32) (a - b) <= 0);
153 : }
154 :
155 : always_inline int
156 1448470 : f_pos_gt (u32 a, u32 b)
157 : {
158 1448470 : return ((i32) (a - b) > 0);
159 : }
160 :
161 : always_inline int
162 18536920 : f_pos_geq (u32 a, u32 b)
163 : {
164 18536920 : return ((i32) (a - b) >= 0);
165 : }
166 :
167 : always_inline u8
168 9721920 : f_chunk_includes_pos (svm_fifo_chunk_t * c, u32 pos)
169 : {
170 9721920 : return (f_pos_geq (pos, c->start_byte)
171 9721920 : && f_pos_lt (pos, c->start_byte + c->length));
172 : }
173 :
174 : always_inline svm_fifo_chunk_t *
175 1435071 : f_start_cptr (svm_fifo_t *f)
176 : {
177 1435071 : return fs_chunk_ptr (f->fs_hdr, f->shr->start_chunk);
178 : }
179 :
180 : always_inline svm_fifo_chunk_t *
181 1609857 : f_end_cptr (svm_fifo_t *f)
182 : {
183 1609857 : return fs_chunk_ptr (f->fs_hdr, f->shr->end_chunk);
184 : }
185 :
186 : always_inline svm_fifo_chunk_t *
187 828070 : f_head_cptr (svm_fifo_t *f)
188 : {
189 828070 : return fs_chunk_ptr (f->fs_hdr, f->shr->head_chunk);
190 : }
191 :
192 : always_inline svm_fifo_chunk_t *
193 1606561 : f_tail_cptr (svm_fifo_t *f)
194 : {
195 1606561 : return fs_chunk_ptr (f->fs_hdr, f->shr->tail_chunk);
196 : }
197 :
198 : always_inline svm_fifo_chunk_t *
199 4573780 : f_cptr (svm_fifo_t *f, fs_sptr_t cp)
200 : {
201 4573780 : return fs_chunk_ptr (f->fs_hdr, cp);
202 : }
203 :
204 : always_inline fs_sptr_t
205 818449 : f_csptr (svm_fifo_t *f, svm_fifo_chunk_t *c)
206 : {
207 818449 : return fs_chunk_sptr (f->fs_hdr, c);
208 : }
209 :
210 : always_inline void
211 207616 : f_csptr_link (svm_fifo_t *f, fs_sptr_t cp, svm_fifo_chunk_t *c)
212 : {
213 207616 : fs_chunk_ptr (f->fs_hdr, cp)->next = fs_chunk_sptr (f->fs_hdr, c);
214 207616 : }
215 :
216 : /**
217 : * Create fifo of requested size
218 : *
219 : * Allocates fifo on current heap.
220 : *
221 : * @param size data size in bytes for fifo to be allocated. Will be
222 : * rounded to the next highest power-of-two value.
223 : * @return pointer to new fifo
224 : */
225 : svm_fifo_t *svm_fifo_alloc (u32 size);
226 : /**
227 : * Initialize fifo
228 : *
229 : * @param f fifo
230 : * @param size size for fifo
231 : */
232 : void svm_fifo_init (svm_fifo_t * f, u32 size);
233 : /**
234 : * Allocate a fifo chunk on heap
235 : *
236 : * If the chunk is allocated on a fifo segment, this should be called
237 : * with the segment's heap pushed.
238 : *
239 : * @param size chunk size in bytes. Will be rounded to the next highest
240 : * power-of-two
241 : * @return new chunk or 0 if alloc failed
242 : */
243 : svm_fifo_chunk_t *svm_fifo_chunk_alloc (u32 size);
244 : /**
245 : * Ensure the whole fifo size is writeable
246 : *
247 : * Allocates enough chunks to cover the whole fifo size.
248 : *
249 : * @param f fifo
250 : */
251 : int svm_fifo_fill_chunk_list (svm_fifo_t * f);
252 : /**
253 : * Provision and return chunks for number of bytes requested
254 : *
255 : * Allocates enough chunks to cover the bytes requested and returns them
256 : * in the fifo segment array. The number of bytes provisioned may be less
257 : * than requested if not enough segments were provided.
258 : *
259 : * @param f fifo
260 : * @param fs array of fifo segments
261 : * @param n_segs length of fifo segments array
262 : * @param len number of bytes to preallocate
263 : * @return number of fifo segments provisioned or error
264 : */
265 : int svm_fifo_provision_chunks (svm_fifo_t *f, svm_fifo_seg_t *fs, u32 n_segs,
266 : u32 len);
267 : /**
268 : * Initialize rbtrees used for ooo lookups
269 : *
270 : * @param f fifo
271 : * @param ooo_type type of ooo operation (0 enqueue, 1 dequeue)
272 : */
273 : void svm_fifo_init_ooo_lookup (svm_fifo_t * f, u8 ooo_type);
274 : /**
275 : * Free fifo and associated state
276 : *
277 : * @param f fifo
278 : */
279 : void svm_fifo_free (svm_fifo_t * f);
280 : /**
281 : * Cleanup fifo chunk lookup rb tree
282 : *
283 : * The rb tree is allocated in segment heap so this should be called
284 : * with it pushed.
285 : *
286 : * @param f fifo to cleanup
287 : */
288 : void svm_fifo_free_chunk_lookup (svm_fifo_t * f);
289 : /**
290 : * Cleanup fifo ooo data
291 : *
292 : * The ooo data is allocated in producer process memory. The fifo
293 : * segment heap should not be pushed.
294 : *
295 : * @param f fifo to cleanup
296 : */
297 : void svm_fifo_free_ooo_data (svm_fifo_t * f);
298 : /**
299 : * Init fifo head and tail
300 : *
301 : * @param f fifo
302 : * @param head head value that will be matched to a chunk
303 : * @param tail tail value that will be matched to a chunk
304 : */
305 : void svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail);
306 : /**
307 : * Clone fifo
308 : *
309 : * Clones single/default chunk fifo. It does not work for fifos with
310 : * multiple chunks.
311 : */
312 : void svm_fifo_clone (svm_fifo_t * df, svm_fifo_t * sf);
313 : /**
314 : * Enqueue data to fifo
315 : *
316 : * Data is enqueued and tail pointer is updated atomically. If the new data
317 : * enqueued partly overlaps or "touches" an out-of-order segment, said segment
318 : * is "consumed" and the number of bytes returned is appropriately updated.
319 : *
320 : * @param f fifo
321 : * @param len length of data to copy
322 : * @param src buffer from where to copy the data
323 : * @return number of contiguous bytes that can be consumed or error
324 : */
325 : int svm_fifo_enqueue (svm_fifo_t * f, u32 len, const u8 * src);
326 : /**
327 : * Enqueue data to fifo with offset
328 : *
329 : * Data is enqueued without updating tail pointer. Instead, an out-of-order
330 : * list of segments is generated and maintained. Fifo takes care of coalescing
331 : * contiguous or overlapping segments.
332 : *
333 : * @param f fifo
334 : * @param offset offset at which to copy the data
335 : * @param len len of data to copy
336 : * @param src buffer from where to copy the data
337 : * @return 0 if enqueue was successful, error otherwise
338 : */
339 : int svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len,
340 : u8 * src);
341 :
342 : /**
343 : * Advance tail pointer
344 : *
345 : * Useful for moving tail pointer after external enqueue.
346 : *
347 : * @param f fifo
348 : * @param len number of bytes to add to tail
349 : */
350 : void svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len);
351 : /**
352 : * Enqueue array of @ref svm_fifo_seg_t in order
353 : *
354 : * @param f fifo
355 : * @param segs array of segments to enqueue
356 : * @param n_segs number of segments
357 : * @param allow_partial if set partial enqueues are allowed
358 : * @return len if enqueue was successful, error otherwise
359 : */
360 : int svm_fifo_enqueue_segments (svm_fifo_t * f, const svm_fifo_seg_t segs[],
361 : u32 n_segs, u8 allow_partial);
362 : /**
363 : * Overwrite fifo head with new data
364 : *
365 : * This should be typically used by dgram transport protocols that need
366 : * to update the dgram header after dequeuing a chunk of data. It assumes
367 : * that the dgram header is at most spread over two chunks.
368 : *
369 : * @param f fifo
370 : * @param src src of new data
371 : * @param len length of new data
372 : */
373 : void svm_fifo_overwrite_head (svm_fifo_t * f, u8 * src, u32 len);
374 : /**
375 : * Dequeue data from fifo
376 : *
377 : * Data is dequeued to consumer provided buffer and head is atomically
378 : * updated. This should not be used in combination with ooo lookups. If
379 : * ooo peeking of data is needed in combination with dequeuing use @ref
380 : * svm_fifo_dequeue_drop.
381 : *
382 : * @param f fifo
383 : * @param len length of data to dequeue
384 : * @param dst buffer to where to dequeue the data
385 : * @return number of bytes dequeued or error
386 : */
387 : int svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst);
388 : /**
389 : * Peek data from fifo
390 : *
391 : * Data is copied from requested offset into provided dst buffer. Head is
392 : * not updated.
393 : *
394 : * @param f fifo
395 : * @param offset offset from which to copy the data
396 : * @param len length of data to copy
397 : * @param dst buffer to where to dequeue the data
398 : * @return number of bytes peeked
399 : */
400 : int svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 len, u8 * dst);
401 : /**
402 : * Dequeue and drop bytes from fifo
403 : *
404 : * Advances fifo head by requested amount of bytes.
405 : *
406 : * @param f fifo
407 : * @param len number of bytes to drop
408 : * @return number of bytes dropped
409 : */
410 : int svm_fifo_dequeue_drop (svm_fifo_t * f, u32 len);
411 : /**
412 : * Dequeue and drop all bytes from fifo
413 : *
414 : * Advances head to tail position.
415 : *
416 : * @param f fifo
417 : */
418 : void svm_fifo_dequeue_drop_all (svm_fifo_t * f);
419 : /**
420 : * Get pointers to fifo chunks data in @ref svm_fifo_seg_t array
421 : *
422 : * Populates fifo segment array with pointers to fifo chunk data and lengths.
423 : * Because this returns pointers to data, it must be paired with
424 : * @ref svm_fifo_dequeue_drop to actually release the fifo chunks after the
425 : * data is consumed.
426 : *
427 : * @param f fifo
428 : * @param offset offset from where to retrieve segments
429 : * @param fs array of fifo segments allocated by caller
430 : * @param n_segs number of fifo segments in array
431 : * @param max_bytes max bytes to be mapped to fifo segments
432 : * @return number of bytes in fifo segments or SVM_FIFO_EEMPTY
433 : */
434 : int svm_fifo_segments (svm_fifo_t *f, u32 offset, svm_fifo_seg_t *fs,
435 : u32 *n_segs, u32 max_bytes);
436 : /**
437 : * Add io events subscriber to list
438 : *
439 : * @param f fifo
440 : * @param sub subscriber opaque index (typically app worker index)
441 : */
442 : void svm_fifo_add_subscriber (svm_fifo_t * f, u8 sub);
443 : /**
444 : * Remove io events subscriber form list
445 : *
446 : * @param f fifo
447 : * @param sub subscriber index to be removed
448 : */
449 : void svm_fifo_del_subscriber (svm_fifo_t * f, u8 subscriber);
450 : /**
451 : * Number of out-of-order segments for fifo
452 : *
453 : * @param f fifo
454 : * @return number of out of order segments
455 : */
456 : u32 svm_fifo_n_ooo_segments (svm_fifo_t * f);
457 : /**
458 : * First out-of-order segment for fifo
459 : *
460 : * @param f fifo
461 : * @return first out-of-order segment for fifo
462 : */
463 : ooo_segment_t *svm_fifo_first_ooo_segment (svm_fifo_t * f);
464 : /**
465 : * Check if fifo is sane. Debug only.
466 : *
467 : * @param f fifo
468 : * @return 1 if sane, 0 otherwise
469 : */
470 : u8 svm_fifo_is_sane (svm_fifo_t * f);
471 : /**
472 : * Number of chunks linked into the fifo
473 : *
474 : * @param f fifo
475 : * @return number of chunks in fifo linked list
476 : */
477 : u32 svm_fifo_n_chunks (svm_fifo_t * f);
478 : format_function_t format_svm_fifo;
479 :
480 : /**
481 : * Fifo max bytes to dequeue optimized for consumer
482 : *
483 : * @param f fifo
484 : * @return max number of bytes that can be dequeued
485 : */
486 : static inline u32
487 41835644 : svm_fifo_max_dequeue_cons (svm_fifo_t * f)
488 : {
489 : u32 tail, head;
490 41835644 : f_load_head_tail_cons (f, &head, &tail);
491 41835644 : return f_cursize (f, head, tail);
492 : }
493 :
494 : /**
495 : * Fifo max bytes to dequeue optimized for producer
496 : *
497 : * @param f fifo
498 : * @return max number of bytes that can be dequeued
499 : */
500 : static inline u32
501 35 : svm_fifo_max_dequeue_prod (svm_fifo_t * f)
502 : {
503 : u32 tail, head;
504 35 : f_load_head_tail_prod (f, &head, &tail);
505 35 : return f_cursize (f, head, tail);
506 : }
507 :
508 : /**
509 : * Fifo max bytes to dequeue
510 : *
511 : * Note: use producer or consumer specific functions for performance:
512 : * @ref svm_fifo_max_dequeue_cons (svm_fifo_t *f)
513 : * @ref svm_fifo_max_dequeue_prod (svm_fifo_t *f)
514 : */
515 : static inline u32
516 415132 : svm_fifo_max_dequeue (svm_fifo_t * f)
517 : {
518 : u32 tail, head;
519 415132 : f_load_head_tail_all_acq (f, &head, &tail);
520 415132 : return f_cursize (f, head, tail);
521 : }
522 :
523 : /**
524 : * Check if fifo is full optimized for producer
525 : *
526 : * @param f fifo
527 : * @return 1 if fifo is full 0 otherwise
528 : */
529 : static inline int
530 : svm_fifo_is_full_prod (svm_fifo_t * f)
531 : {
532 : return (svm_fifo_max_dequeue_prod (f) == f->shr->size);
533 : }
534 :
535 : /* Check if fifo is full.
536 : *
537 : * Note: use producer or consumer specific functions for performance.
538 : * @ref svm_fifo_is_full_prod (svm_fifo_t * f)
539 : * add cons version if needed
540 : */
541 : static inline int
542 : svm_fifo_is_full (svm_fifo_t * f)
543 : {
544 : return (svm_fifo_max_dequeue (f) == f->shr->size);
545 : }
546 :
547 : /**
548 : * Check if fifo is empty optimized for consumer
549 : *
550 : * @param f fifo
551 : * @return 1 if fifo is empty 0 otherwise
552 : */
553 : static inline int
554 1891784 : svm_fifo_is_empty_cons (svm_fifo_t * f)
555 : {
556 1891784 : return (svm_fifo_max_dequeue_cons (f) == 0);
557 : }
558 :
559 : /**
560 : * Check if fifo is empty optimized for producer
561 : *
562 : * @param f fifo
563 : * @return 1 if fifo is empty 0 otherwise
564 : */
565 : static inline int
566 35 : svm_fifo_is_empty_prod (svm_fifo_t * f)
567 : {
568 35 : return (svm_fifo_max_dequeue_prod (f) == 0);
569 : }
570 :
571 : /**
572 : * Check if fifo is empty
573 : *
574 : * Note: use producer or consumer specific functions for perfomance.
575 : * @ref svm_fifo_is_empty_cons (svm_fifo_t * f)
576 : * @ref svm_fifo_is_empty_prod (svm_fifo_t * f)
577 : */
578 : static inline int
579 168608 : svm_fifo_is_empty (svm_fifo_t * f)
580 : {
581 168608 : return (svm_fifo_max_dequeue (f) == 0);
582 : }
583 :
584 : /**
585 : * Check if fifo is wrapped
586 : *
587 : * @param f fifo
588 : * @return 1 if 'normalized' head is ahead of tail
589 : */
590 : static inline u8
591 : svm_fifo_is_wrapped (svm_fifo_t * f)
592 : {
593 : u32 head, tail;
594 : f_load_head_tail_all_acq (f, &head, &tail);
595 : return head > tail;
596 : }
597 :
598 : /**
599 : * Maximum number of bytes that can be enqueued into fifo
600 : *
601 : * Optimized for producer
602 : *
603 : * @param f fifo
604 : * @return max number of bytes that can be enqueued into fifo
605 : */
606 : static inline u32
607 10073705 : svm_fifo_max_enqueue_prod (svm_fifo_t * f)
608 : {
609 : u32 head, tail;
610 10073705 : f_load_head_tail_prod (f, &head, &tail);
611 10073705 : return f_free_count (f, head, tail);
612 : }
613 :
614 : /* Maximum number of bytes that can be enqueued into fifo
615 : *
616 : * Note: use producer or consumer specific functions for performance.
617 : * @ref svm_fifo_max_enqueue_prod (svm_fifo_t *f)
618 : * add consumer specific version if needed.
619 : */
620 : static inline u32
621 86835 : svm_fifo_max_enqueue (svm_fifo_t * f)
622 : {
623 : u32 head, tail;
624 86835 : f_load_head_tail_all_acq (f, &head, &tail);
625 86835 : return f_free_count (f, head, tail);
626 : }
627 :
628 : /**
629 : * Max contiguous chunk of data that can be read.
630 : *
631 : * Should only be called by consumers.
632 : */
633 : u32 svm_fifo_max_read_chunk (svm_fifo_t * f);
634 :
635 : /**
636 : * Max contiguous chunk of data that can be written
637 : *
638 : * Should only be called by producers
639 : */
640 : u32 svm_fifo_max_write_chunk (svm_fifo_t * f);
641 :
642 : /**
643 : * Fifo number of subscribers getter
644 : *
645 : * @param f fifo
646 : * @return number of subscribers
647 : */
648 : static inline u8
649 181297 : svm_fifo_n_subscribers (svm_fifo_t * f)
650 : {
651 181297 : return f->shr->n_subscribers;
652 : }
653 :
654 : /**
655 : * Check if fifo has out-of-order data
656 : *
657 : * @param f fifo
658 : * @return 1 if fifo has ooo data, 0 otherwise
659 : */
660 : static inline u8
661 35 : svm_fifo_has_ooo_data (svm_fifo_t * f)
662 : {
663 35 : return f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX;
664 : }
665 :
666 : static inline ooo_segment_t *
667 0 : svm_fifo_newest_ooo_segment (svm_fifo_t * f)
668 : {
669 0 : if (f->ooos_newest == OOO_SEGMENT_INVALID_INDEX)
670 0 : return 0;
671 0 : return pool_elt_at_index (f->ooo_segments, f->ooos_newest);
672 : }
673 :
674 : static inline void
675 0 : svm_fifo_newest_ooo_segment_reset (svm_fifo_t * f)
676 : {
677 0 : f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
678 0 : }
679 :
680 : static inline u32
681 1 : ooo_segment_offset_prod (svm_fifo_t * f, ooo_segment_t * s)
682 : {
683 : u32 tail;
684 : /* load-relaxed: producer owned index */
685 1 : tail = f->shr->tail;
686 :
687 1 : return (s->start - tail);
688 : }
689 :
690 : static inline u32
691 0 : ooo_segment_length (svm_fifo_t * f, ooo_segment_t * s)
692 : {
693 0 : return s->length;
694 : }
695 :
696 : static inline u32
697 1303792 : svm_fifo_size (svm_fifo_t * f)
698 : {
699 1303792 : return f->shr->size;
700 : }
701 :
702 : static inline void
703 8410 : svm_fifo_set_size (svm_fifo_t * f, u32 size)
704 : {
705 8410 : if (size > (1 << f->fs_hdr->max_log2_fifo_size))
706 1 : return;
707 8409 : fsh_virtual_mem_update (f->fs_hdr, f->shr->slice_index,
708 8409 : (int) f->shr->size - size);
709 8409 : f->shr->size = size;
710 : }
711 :
712 : /**
713 : * Check if fifo has io event
714 : *
715 : * @param f fifo
716 : * @return 1 if fifo has event, 0 otherwise
717 : */
718 : static inline int
719 13679114 : svm_fifo_has_event (svm_fifo_t * f)
720 : {
721 13679114 : return f->shr->has_event;
722 : }
723 :
724 : /**
725 : * Set fifo event flag.
726 : *
727 : * Forces release semantics.
728 : *
729 : * @param f fifo
730 : * @return 1 if flag was not set, 0 otherwise
731 : */
732 : always_inline u8
733 466067 : svm_fifo_set_event (svm_fifo_t * f)
734 : {
735 466067 : return !clib_atomic_swap_rel_n (&f->shr->has_event, 1);
736 : }
737 :
738 : /**
739 : * Unset fifo event flag.
740 : *
741 : * Forces acquire semantics
742 : *
743 : * @param f fifo
744 : */
745 : always_inline void
746 8321032 : svm_fifo_unset_event (svm_fifo_t * f)
747 : {
748 8321032 : clib_atomic_swap_acq_n (&f->shr->has_event, 0);
749 8321032 : }
750 :
751 : /**
752 : * Set specific want notification flag
753 : *
754 : * For list of flags see @ref svm_fifo_deq_ntf_t
755 : *
756 : * @param f fifo
757 : * @param ntf_type type of notification requested
758 : */
759 : static inline void
760 7513630 : svm_fifo_add_want_deq_ntf (svm_fifo_t * f, u8 ntf_type)
761 : {
762 7513630 : __atomic_or_fetch (&f->shr->want_deq_ntf, ntf_type, __ATOMIC_RELEASE);
763 7513630 : }
764 :
765 : /**
766 : * Clear specific want notification flag
767 : *
768 : * For list of flags see @ref svm_fifo_ntf_t
769 : *
770 : * @param f fifo
771 : * @param ntf_type type of notification to be cleared
772 : */
773 : static inline void
774 22430 : svm_fifo_del_want_deq_ntf (svm_fifo_t * f, u8 ntf_type)
775 : {
776 22430 : __atomic_and_fetch (&f->shr->want_deq_ntf, ~ntf_type, __ATOMIC_RELEASE);
777 22430 : }
778 :
779 : /**
780 : * Get want notification flag
781 : *
782 : * Done atomically with acquire memory ordering
783 : *
784 : * @param f fifo
785 : * @return value of want_deq_ntf flag
786 : */
787 : static inline u32
788 545781 : svm_fifo_get_want_deq_ntf (svm_fifo_t *f)
789 : {
790 545781 : return clib_atomic_load_acq_n (&f->shr->want_deq_ntf);
791 : }
792 :
793 : /**
794 : * Clear the want notification flag and set has notification
795 : *
796 : * Should be used after enqueuing an event. This clears the
797 : * SVM_FIFO_WANT_NOTIF flag but it does not clear
798 : * SVM_FIFO_WANT_NOTIF_IF_FULL. If the latter was set, has_ntf is
799 : * set to avoid enqueueing events for for all dequeue operations until
800 : * it is manually cleared.
801 : *
802 : * @param f fifo
803 : */
804 : static inline void
805 23383 : svm_fifo_clear_deq_ntf (svm_fifo_t * f)
806 : {
807 23383 : u32 want_deq_ntf = svm_fifo_get_want_deq_ntf (f);
808 : /* Set the flag if want ntf if full or empty was requested */
809 23383 : if (want_deq_ntf &
810 : (SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL | SVM_FIFO_WANT_DEQ_NOTIF_IF_EMPTY))
811 579 : clib_atomic_store_rel_n (&f->shr->has_deq_ntf, 1);
812 23383 : if (want_deq_ntf & SVM_FIFO_WANT_DEQ_NOTIF)
813 22403 : svm_fifo_del_want_deq_ntf (f, SVM_FIFO_WANT_DEQ_NOTIF);
814 23383 : }
815 :
816 : /**
817 : * Get has dequeue notification flag
818 : *
819 : * Done atomically with acquire memory ordering
820 : *
821 : * @param f fifo
822 : * @return has_deq_ntf flag
823 : */
824 : static inline u32
825 2976 : svm_fifo_has_deq_ntf (svm_fifo_t *f)
826 : {
827 2976 : return clib_atomic_load_acq_n (&f->shr->has_deq_ntf);
828 : }
829 :
830 : /**
831 : * Clear has notification flag
832 : *
833 : * The fifo generates only one event per SVM_FIFO_WANT_NOTIF_IF_FULL
834 : * request and sets has_ntf. To received new events the flag must be
835 : * cleared using this function.
836 : *
837 : * @param f fifo
838 : */
839 : static inline void
840 579 : svm_fifo_reset_has_deq_ntf (svm_fifo_t * f)
841 : {
842 579 : f->shr->has_deq_ntf = 0;
843 579 : }
844 :
845 : /**
846 : * Check if fifo needs dequeue notification
847 : *
848 : * Determines based on notification request flags and state of the fifo if
849 : * an event should be generated.
850 : *
851 : * @param f fifo
852 : * @param n_last_deq number of bytes last dequeued
853 : * @return 1 if event should be generated, 0 otherwise
854 : */
855 : static inline u8
856 522398 : svm_fifo_needs_deq_ntf (svm_fifo_t * f, u32 n_last_deq)
857 : {
858 522398 : u32 want_ntf = svm_fifo_get_want_deq_ntf (f);
859 :
860 522398 : if (want_ntf == SVM_FIFO_NO_DEQ_NOTIF)
861 497019 : return 0;
862 25379 : else if (want_ntf & SVM_FIFO_WANT_DEQ_NOTIF)
863 22403 : return (svm_fifo_max_enqueue (f) >= f->shr->deq_thresh);
864 2976 : if (want_ntf & SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL)
865 : {
866 2976 : u32 max_deq = svm_fifo_max_dequeue_cons (f);
867 2976 : u32 size = f->shr->size;
868 2976 : if (max_deq < size && max_deq + n_last_deq >= size &&
869 0 : !svm_fifo_has_deq_ntf (f))
870 0 : return 1;
871 : }
872 2976 : if (want_ntf & SVM_FIFO_WANT_DEQ_NOTIF_IF_EMPTY)
873 : {
874 2976 : if (!svm_fifo_has_deq_ntf (f) && svm_fifo_is_empty (f))
875 1714 : return 1;
876 : }
877 1262 : return 0;
878 : }
879 :
880 : /**
881 : * Set the fifo dequeue threshold which will be used for notifications.
882 : *
883 : * Note: If not set, by default threshold is zero, equivalent to
884 : * generating notification on each dequeue event.
885 : */
886 : static inline void
887 0 : svm_fifo_set_deq_thresh (svm_fifo_t *f, u32 thresh)
888 : {
889 0 : f->shr->deq_thresh = thresh;
890 0 : }
891 :
892 : #endif /* __included_ssvm_fifo_h__ */
893 :
894 : /*
895 : * fd.io coding-style-patch-verification: ON
896 : *
897 : * Local Variables:
898 : * eval: (c-set-style "gnu")
899 : * End:
900 : */
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