FD.io VPP  v20.01-48-g3e0dafb74
Vector Packet Processing
svm_fifo.c
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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 
20 #include <svm/svm_fifo.h>
21 #include <vppinfra/cpu.h>
22 
24  svm_fifo_chunk_t * c, u32 tail_idx, const u8 * src, u32 len,
26 {
27  u32 n_chunk;
28 
29  ASSERT (tail_idx >= c->start_byte && tail_idx < c->start_byte + c->length);
30 
31  tail_idx -= c->start_byte;
32  n_chunk = c->length - tail_idx;
33  if (n_chunk <= len)
34  {
35  u32 to_copy = len;
36  clib_memcpy_fast (&c->data[tail_idx], src, n_chunk);
37  c = c->next;
38  while ((to_copy -= n_chunk))
39  {
40  n_chunk = clib_min (c->length, to_copy);
41  clib_memcpy_fast (&c->data[0], src + (len - to_copy), n_chunk);
42  c = c->length <= to_copy ? c->next : c;
43  }
44  if (*last)
45  *last = c;
46  }
47  else
48  {
49  clib_memcpy_fast (&c->data[tail_idx], src, len);
50  }
51 }
52 
54  svm_fifo_chunk_t * c, u32 head_idx, u8 * dst, u32 len,
56 {
57  u32 n_chunk;
58 
59  ASSERT (head_idx >= c->start_byte && head_idx < c->start_byte + c->length);
60 
61  head_idx -= c->start_byte;
62  n_chunk = c->length - head_idx;
63  if (n_chunk <= len)
64  {
65  u32 to_copy = len;
66  clib_memcpy_fast (dst, &c->data[head_idx], n_chunk);
67  c = c->next;
68  while ((to_copy -= n_chunk))
69  {
70  n_chunk = clib_min (c->length, to_copy);
71  clib_memcpy_fast (dst + (len - to_copy), &c->data[0], n_chunk);
72  c = c->length <= to_copy ? c->next : c;
73  }
74  if (*last)
75  *last = c;
76  }
77  else
78  {
79  clib_memcpy_fast (dst, &c->data[head_idx], len);
80  }
81 }
82 
83 #ifndef CLIB_MARCH_VARIANT
84 
85 static inline void
87  const u8 * src, u32 len, svm_fifo_chunk_t ** last)
88 {
90  last);
91 }
92 
93 static inline void
96 {
98  last);
99 }
100 
101 static inline u8
103 {
104  return (f_distance_to (f, a, tail) < f_distance_to (f, b, tail));
105 }
106 
107 static inline u8
109 {
110  return (f_distance_to (f, a, tail) <= f_distance_to (f, b, tail));
111 }
112 
113 static inline u8
115 {
116  return (f_distance_to (f, a, tail) > f_distance_to (f, b, tail));
117 }
118 
119 static inline u32
121 {
122  return f_distance_to (f, a, tail) - f_distance_to (f, b, tail);
123 }
124 
125 static inline u32
127 {
128  return (s->start + s->length) % f->size;
129 }
130 
131 void
133 {
134  pool_free (f->ooo_segments);
135 }
136 
137 static inline ooo_segment_t *
139 {
141  return 0;
142  return pool_elt_at_index (f->ooo_segments, s->prev);
143 }
144 
145 static inline ooo_segment_t *
147 {
149  return 0;
150  return pool_elt_at_index (f->ooo_segments, s->next);
151 }
152 
153 static inline ooo_segment_t *
154 ooo_segment_alloc (svm_fifo_t * f, u32 start, u32 length)
155 {
156  ooo_segment_t *s;
157 
158  pool_get (f->ooo_segments, s);
159 
160  s->start = start;
161  s->length = length;
163 
164  return s;
165 }
166 
167 static inline void
169 {
170  ooo_segment_t *cur, *prev = 0, *next = 0;
171  cur = pool_elt_at_index (f->ooo_segments, index);
172 
173  if (cur->next != OOO_SEGMENT_INVALID_INDEX)
174  {
175  next = pool_elt_at_index (f->ooo_segments, cur->next);
176  next->prev = cur->prev;
177  }
178 
179  if (cur->prev != OOO_SEGMENT_INVALID_INDEX)
180  {
181  prev = pool_elt_at_index (f->ooo_segments, cur->prev);
182  prev->next = cur->next;
183  }
184  else
185  {
186  f->ooos_list_head = cur->next;
187  }
188 
189  pool_put (f->ooo_segments, cur);
190 }
191 
192 /**
193  * Add segment to fifo's out-of-order segment list. Takes care of merging
194  * adjacent segments and removing overlapping ones.
195  */
196 static void
197 ooo_segment_add (svm_fifo_t * f, u32 offset, u32 head, u32 tail, u32 length)
198 {
199  ooo_segment_t *s, *new_s, *prev, *next, *it;
200  u32 new_index, s_end_pos, s_index;
201  u32 offset_pos, offset_end_pos;
202 
203  ASSERT (offset + length <= f_distance_to (f, head, tail) || head == tail);
204 
205  offset_pos = (tail + offset) % f->size;
206  offset_end_pos = (tail + offset + length) % f->size;
207 
208  f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
209 
210  if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
211  {
212  s = ooo_segment_alloc (f, offset_pos, length);
213  f->ooos_list_head = s - f->ooo_segments;
214  f->ooos_newest = f->ooos_list_head;
215  return;
216  }
217 
218  /* Find first segment that starts after new segment */
219  s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
220  while (s->next != OOO_SEGMENT_INVALID_INDEX
221  && position_lt (f, s->start, offset_pos, tail))
222  s = pool_elt_at_index (f->ooo_segments, s->next);
223 
224  /* If we have a previous and we overlap it, use it as starting point */
225  prev = ooo_segment_prev (f, s);
226  if (prev
227  && position_leq (f, offset_pos, ooo_segment_end_pos (f, prev), tail))
228  {
229  s = prev;
230  s_end_pos = ooo_segment_end_pos (f, s);
231 
232  /* Since we have previous, offset start position cannot be smaller
233  * than prev->start. Check tail */
234  ASSERT (position_lt (f, s->start, offset_pos, tail));
235  goto check_tail;
236  }
237 
238  s_index = s - f->ooo_segments;
239  s_end_pos = ooo_segment_end_pos (f, s);
240 
241  /* No overlap, add before current segment */
242  if (position_lt (f, offset_end_pos, s->start, tail))
243  {
244  new_s = ooo_segment_alloc (f, offset_pos, length);
245  new_index = new_s - f->ooo_segments;
246 
247  /* Pool might've moved, get segment again */
248  s = pool_elt_at_index (f->ooo_segments, s_index);
250  {
251  new_s->prev = s->prev;
252  prev = pool_elt_at_index (f->ooo_segments, new_s->prev);
253  prev->next = new_index;
254  }
255  else
256  {
257  /* New head */
258  f->ooos_list_head = new_index;
259  }
260 
261  new_s->next = s_index;
262  s->prev = new_index;
263  f->ooos_newest = new_index;
264  return;
265  }
266  /* No overlap, add after current segment */
267  else if (position_gt (f, offset_pos, s_end_pos, tail))
268  {
269  new_s = ooo_segment_alloc (f, offset_pos, length);
270  new_index = new_s - f->ooo_segments;
271 
272  /* Pool might've moved, get segment again */
273  s = pool_elt_at_index (f->ooo_segments, s_index);
274 
275  /* Needs to be last */
277 
278  new_s->prev = s_index;
279  s->next = new_index;
280  f->ooos_newest = new_index;
281 
282  return;
283  }
284 
285  /*
286  * Merge needed
287  */
288 
289  /* Merge at head */
290  if (position_lt (f, offset_pos, s->start, tail))
291  {
292  s->start = offset_pos;
293  s->length = position_diff (f, s_end_pos, s->start, tail);
294  f->ooos_newest = s - f->ooo_segments;
295  }
296 
297 check_tail:
298 
299  /* Overlapping tail */
300  if (position_gt (f, offset_end_pos, s_end_pos, tail))
301  {
302  s->length = position_diff (f, offset_end_pos, s->start, tail);
303 
304  /* Remove the completely overlapped segments in the tail */
305  it = ooo_segment_next (f, s);
306  while (it && position_leq (f, ooo_segment_end_pos (f, it),
307  offset_end_pos, tail))
308  {
309  next = ooo_segment_next (f, it);
310  ooo_segment_free (f, it - f->ooo_segments);
311  it = next;
312  }
313 
314  /* If partial overlap with last, merge */
315  if (it && position_leq (f, it->start, offset_end_pos, tail))
316  {
317  s->length = position_diff (f, ooo_segment_end_pos (f, it),
318  s->start, tail);
319  ooo_segment_free (f, it - f->ooo_segments);
320  }
321  f->ooos_newest = s - f->ooo_segments;
322  }
323 }
324 
325 /**
326  * Removes segments that can now be enqueued because the fifo's tail has
327  * advanced. Returns the number of bytes added to tail.
328  */
329 static int
330 ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail)
331 {
332  u32 s_index, bytes = 0;
333  ooo_segment_t *s;
334  i32 diff;
335 
336  s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
337  diff = f_distance_from (f, s->start, *tail);
338 
339  ASSERT (diff != n_bytes_enqueued);
340 
341  if (diff > n_bytes_enqueued)
342  return 0;
343 
344  /* If last tail update overlaps one/multiple ooo segments, remove them */
345  while (0 <= diff && diff < n_bytes_enqueued)
346  {
347  s_index = s - f->ooo_segments;
348 
349  /* Segment end is beyond the tail. Advance tail and remove segment */
350  if (s->length > diff)
351  {
352  bytes = s->length - diff;
353  *tail = (*tail + bytes) % f->size;
354  ooo_segment_free (f, s_index);
355  break;
356  }
357 
358  /* If we have next go on */
360  {
361  s = pool_elt_at_index (f->ooo_segments, s->next);
362  diff = f_distance_from (f, s->start, *tail);
363  ooo_segment_free (f, s_index);
364  }
365  /* End of search */
366  else
367  {
368  ooo_segment_free (f, s_index);
369  break;
370  }
371  }
372 
373  ASSERT (bytes <= f->nitems);
374  return bytes;
375 }
376 
377 static ooo_segment_t *
379 {
380  ooo_segment_t *s;
381 
382  if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
383  return 0;
384 
386  while (s->next != OOO_SEGMENT_INVALID_INDEX)
387  s = pool_elt_at_index (f->ooo_segments, s->next);
388  return s;
389 }
390 
391 void
393 {
394  f->size = size;
395  /*
396  * usable size of the fifo set to rounded_data_size - 1
397  * to differentiate between free fifo and empty fifo.
398  */
399  f->nitems = f->size - 1;
400  f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
401  f->segment_index = SVM_FIFO_INVALID_INDEX;
402  f->refcnt = 1;
403  f->head = f->tail = f->flags = 0;
404  f->head_chunk = f->tail_chunk = f->ooo_enq = f->ooo_deq = f->start_chunk;
405 }
406 
407 void
409 {
410  svm_fifo_chunk_t *c, *prev;
411 
412  if (f->start_chunk->next == f->start_chunk)
413  return;
414 
416  rb_tree_init (&f->chunk_lookup);
417  rb_tree_add2 (&f->chunk_lookup, 0, pointer_to_uword (f->start_chunk));
418 
419  f->start_chunk->start_byte = 0;
420  prev = f->start_chunk;
421  c = prev->next;
422 
423  while (c != f->start_chunk)
424  {
425  c->start_byte = prev->start_byte + prev->length;
426  rb_tree_add2 (&f->chunk_lookup, c->start_byte, pointer_to_uword (c));
427  prev = c;
428  c = c->next;
429  }
430 }
431 
432 /**
433  * Creates a fifo in the current heap. Fails vs blow up the process
434  */
435 svm_fifo_t *
436 svm_fifo_create (u32 data_size_in_bytes)
437 {
438  u32 rounded_data_size;
440  svm_fifo_t *f;
441 
443  if (f == 0)
444  return 0;
445 
446  clib_memset (f, 0, sizeof (*f));
447 
448  /* always round fifo data size to the next highest power-of-two */
449  rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
450  c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_data_size,
452  if (!c)
453  {
454  clib_mem_free (f);
455  return 0;
456  }
457 
458  c->next = c;
459  c->start_byte = 0;
460  c->length = data_size_in_bytes;
461  f->start_chunk = f->end_chunk = c;
462 
463  svm_fifo_init (f, data_size_in_bytes);
464  return f;
465 }
466 
467 /**
468  * Creates a fifo chunk in the current heap
469  */
472 {
474  u32 rounded_size;
475 
476  /* round chunk size to the next highest power-of-two */
477  rounded_size = (1 << (max_log2 (size)));
478  c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_size,
480  if (c == 0)
481  return 0;
482 
483  clib_memset (c, 0, sizeof (*c));
484  c->length = rounded_size;
485  return c;
486 }
487 
488 static inline u8
490 {
491  return (pos >= c->start_byte && pos < c->start_byte + c->length);
492 }
493 
494 /**
495  * Find chunk for given byte position
496  *
497  * @param f fifo
498  * @param pos normalized position in fifo
499  *
500  * @return chunk that includes given position or 0
501  */
502 static svm_fifo_chunk_t *
504 {
505  rb_tree_t *rt = &f->chunk_lookup;
506  rb_node_t *cur, *prev;
508 
509  cur = rb_node (rt, rt->root);
510  while (pos != cur->key)
511  {
512  prev = cur;
513  if (pos < cur->key)
514  cur = rb_node_left (rt, cur);
515  else
516  cur = rb_node_right (rt, cur);
517 
518  if (rb_node_is_tnil (rt, cur))
519  {
520  /* Hit tnil as a left child. Find predecessor */
521  if (pos < prev->key)
522  {
523  cur = rb_tree_predecessor (rt, prev);
524  if (rb_node_is_tnil (rt, cur))
525  return 0;
527  if (svm_fifo_chunk_includes_pos (c, pos))
528  return c;
529  return 0;
530  }
531  /* Hit tnil as a right child. Check if this is the one */
533  if (svm_fifo_chunk_includes_pos (c, pos))
534  return c;
535 
536  return 0;
537  }
538  }
539 
540  if (!rb_node_is_tnil (rt, cur))
541  return uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
542  return 0;
543 }
544 
545 static inline void
547 {
548  svm_fifo_chunk_t *prev;
549  u32 add_bytes = 0;
550 
551  if (!c)
552  return;
553 
554  f->end_chunk->next = c;
555  while (c)
556  {
557  add_bytes += c->length;
558  prev = c;
559  c = c->next;
560  }
561  f->end_chunk = prev;
562  prev->next = f->start_chunk;
563  f->size += add_bytes;
564  f->nitems = f->size - 1;
565  f->new_chunks = 0;
566 }
567 
568 static void
570 {
571  if (new_head > f->tail)
572  return;
573 
574  svm_fifo_grow (f, f->new_chunks);
575  f->flags &= ~SVM_FIFO_F_GROW;
576 }
577 
578 void
580 {
581  svm_fifo_chunk_t *cur, *prev;
582 
583  /* Initialize rbtree if needed and add default chunk to it. Expectation is
584  * that this is called with the heap where the rbtree's pool is pushed. */
585  if (!(f->flags & SVM_FIFO_F_MULTI_CHUNK))
586  {
587  ASSERT (f->start_chunk->next == f->start_chunk);
588  rb_tree_init (&f->chunk_lookup);
589  rb_tree_add2 (&f->chunk_lookup, 0, pointer_to_uword (f->start_chunk));
590  f->flags |= SVM_FIFO_F_MULTI_CHUNK;
591  }
592 
593  /* If fifo is not wrapped, update the size now */
594  if (!svm_fifo_is_wrapped (f))
595  {
596  /* Initialize chunks and add to lookup rbtree */
597  cur = c;
598  if (f->new_chunks)
599  {
600  prev = f->new_chunks;
601  while (prev->next)
602  prev = prev->next;
603  prev->next = c;
604  }
605  else
606  prev = f->end_chunk;
607 
608  while (cur)
609  {
610  cur->start_byte = prev->start_byte + prev->length;
611  rb_tree_add2 (&f->chunk_lookup, cur->start_byte,
612  pointer_to_uword (cur));
613  prev = cur;
614  cur = cur->next;
615  }
616 
617  ASSERT (!f->new_chunks);
618  svm_fifo_grow (f, c);
619  return;
620  }
621 
622  /* Wrapped */
623  if (f->flags & SVM_FIFO_F_SINGLE_THREAD_OWNED)
624  {
625  ASSERT (f->master_thread_index == os_get_thread_index ());
626 
627  if (!f->new_chunks && f->head_chunk != f->tail_chunk)
628  {
629  u32 head = 0, tail = 0;
630  f_load_head_tail_cons (f, &head, &tail);
631 
632  svm_fifo_chunk_t *tmp = f->tail_chunk->next;
633 
634  prev = f->tail_chunk;
635  u32 add_bytes = 0;
636  cur = prev->next;
637  while (cur != f->start_chunk)
638  {
639  /* remove any existing rb_tree entry */
640  rb_tree_del (&f->chunk_lookup, cur->start_byte);
641  cur = cur->next;
642  }
643 
644  /* insert new chunk after the tail_chunk */
645  f->tail_chunk->next = c;
646  while (c)
647  {
648  add_bytes += c->length;
649  c->start_byte = prev->start_byte + prev->length;
650  rb_tree_add2 (&f->chunk_lookup, c->start_byte,
651  pointer_to_uword (c));
652 
653  prev = c;
654  c = c->next;
655  }
656  prev->next = tmp;
657 
658  /* shift existing chunks along */
659  cur = tmp;
660  while (cur != f->start_chunk)
661  {
662  cur->start_byte = prev->start_byte + prev->length;
663  rb_tree_add2 (&f->chunk_lookup, cur->start_byte,
664  pointer_to_uword (cur));
665  prev = cur;
666  cur = cur->next;
667  }
668 
669  f->size += add_bytes;
670  f->nitems = f->size - 1;
671  f->new_chunks = 0;
672  head += add_bytes;
673 
674  clib_atomic_store_rel_n (&f->head, head);
675  ASSERT (svm_fifo_is_sane (f));
676 
677  return;
678  }
679  }
680 
681  /* Wrapped, and optimization of single-thread-owned fifo cannot be applied */
682  /* Initialize chunks and add to lookup rbtree */
683  cur = c;
684  if (f->new_chunks)
685  {
686  prev = f->new_chunks;
687  while (prev->next)
688  prev = prev->next;
689  prev->next = c;
690  }
691  else
692  prev = f->end_chunk;
693 
694  while (cur)
695  {
696  cur->start_byte = prev->start_byte + prev->length;
697  rb_tree_add2 (&f->chunk_lookup, cur->start_byte,
698  pointer_to_uword (cur));
699  prev = cur;
700  cur = cur->next;
701  }
702 
703  /* Postpone size update */
704  if (!f->new_chunks)
705  {
706  f->new_chunks = c;
707  f->flags |= SVM_FIFO_F_GROW;
708  }
709 }
710 
711 /**
712  * Removes chunks that are after fifo end byte
713  */
716 {
717  svm_fifo_chunk_t *list, *cur;
718 
719  f->flags &= ~SVM_FIFO_F_COLLECT_CHUNKS;
720 
721  list = f->new_chunks;
722  f->new_chunks = 0;
723  cur = list;
724  while (cur)
725  {
726  rb_tree_del (&f->chunk_lookup, cur->start_byte);
727  cur = cur->next;
728  }
729 
730  return list;
731 }
732 
733 void
735 {
736  u32 len_to_shrink = 0, tail_pos, len, last_pos;
737  svm_fifo_chunk_t *cur, *prev, *next, *start;
738 
739  tail_pos = tail;
740  if (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX)
741  {
743  tail_pos = ooo_segment_end_pos (f, last);
744  }
745 
746  if (f->size_decrement)
747  {
748  /* Figure out available free space considering that there may be
749  * ooo segments */
750  len = clib_min (f->size_decrement, f_free_count (f, head, tail_pos));
751  f->nitems -= len;
752  f->size_decrement -= len;
753  }
754 
755  /* Remove tail chunks if the following hold:
756  * - not wrapped
757  * - last used byte less than start of last chunk
758  */
759  if (tail_pos >= head && tail_pos < f->end_chunk->start_byte)
760  {
761  /* Lookup the last position not to be removed. Since size still needs
762  * to be nitems + 1, nitems must fall within the usable space. Also,
763  * first segment is not removable, so tail_pos can be 0. */
764  last_pos = tail_pos > 0 ? tail_pos - 1 : tail_pos;
765  prev = svm_fifo_find_chunk (f, clib_max (f->nitems, last_pos));
766  next = prev->next;
767  /* If tail_pos is first position in next, skip the chunk, otherwise,
768  * we must update the tail and, if fifo size is 0, even the head.
769  * We should not invalidate the tail for the caller and must not change
770  * consumer owned variables from code that's typically called by the
771  * producer */
772  if (next->start_byte == tail_pos)
773  {
774  prev = next;
775  next = next->next;
776  }
777  while (next != f->start_chunk)
778  {
779  cur = next;
780  next = cur->next;
781  len_to_shrink += cur->length;
782  }
783  if (len_to_shrink)
784  {
785  f->size -= len_to_shrink;
786  start = prev->next;
787  prev->next = f->start_chunk;
788  f->end_chunk = prev;
789  cur->next = f->new_chunks;
790  f->new_chunks = start;
791  }
792  }
793 
794  if (!f->size_decrement && f->size == f->nitems + 1)
795  {
796  f->flags &= ~SVM_FIFO_F_SHRINK;
797  f->flags |= SVM_FIFO_F_COLLECT_CHUNKS;
798  if (f->start_chunk == f->start_chunk->next)
799  f->flags &= ~SVM_FIFO_F_MULTI_CHUNK;
800  }
801 }
802 
803 /**
804  * Request to reduce fifo size by amount of bytes
805  */
806 int
808 {
809  svm_fifo_chunk_t *cur;
810  u32 actual_len = 0;
811 
812  /* Abort if trying to reduce by more than fifo size or if
813  * fifo is undergoing resizing already */
814  if (len >= f->size || f->size > f->nitems + 1
815  || (f->flags & SVM_FIFO_F_SHRINK) || (f->flags & SVM_FIFO_F_GROW))
816  return 0;
817 
818  /* last chunk that will not be removed */
819  cur = svm_fifo_find_chunk (f, f->nitems - len);
820 
821  /* sum length of chunks that will be removed */
822  cur = cur->next;
823  while (cur != f->start_chunk)
824  {
825  actual_len += cur->length;
826  cur = cur->next;
827  }
828 
829  ASSERT (actual_len <= len);
830  if (!actual_len)
831  return 0;
832 
833  f->size_decrement = actual_len;
834  f->flags |= SVM_FIFO_F_SHRINK;
835 
836  if (try_shrink)
837  {
838  u32 head, tail;
839  f_load_head_tail_prod (f, &head, &tail);
840  svm_fifo_try_shrink (f, head, tail);
841  }
842 
843  return actual_len;
844 }
845 
846 void
848 {
849  rb_tree_free_nodes (&f->chunk_lookup);
850 }
851 
852 void
854 {
855  ASSERT (f->refcnt > 0);
856 
857  if (--f->refcnt == 0)
858  {
859  /* ooo data is not allocated on segment heap */
861  clib_mem_free (f);
862  }
863 }
864 
865 void
867 {
868  u32 n_chunk;
869  u32 head, tail, head_idx;
871 
872  ASSERT (len <= f->nitems);
873 
874  f_load_head_tail_cons (f, &head, &tail);
875  c = f->head_chunk;
876  head_idx = head - c->start_byte;
877  n_chunk = c->length - head_idx;
878  if (len <= n_chunk)
879  clib_memcpy_fast (&c->data[head_idx], src, len);
880  else
881  {
882  clib_memcpy_fast (&c->data[head_idx], src, n_chunk);
883  clib_memcpy_fast (&c->next->data[0], src + n_chunk, len - n_chunk);
884  }
885 }
886 
887 int
889 {
890  u32 tail, head, free_count;
891 
892  f_load_head_tail_prod (f, &head, &tail);
893 
894  /* free space in fifo can only increase during enqueue: SPSC */
895  free_count = f_free_count (f, head, tail);
896 
897  f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
898 
899  if (PREDICT_FALSE (free_count == 0))
900  return SVM_FIFO_EFULL;
901 
902  /* number of bytes we're going to copy */
903  len = clib_min (free_count, len);
904  svm_fifo_copy_to_chunk (f, f->tail_chunk, tail, src, len, &f->tail_chunk);
905  tail = (tail + len) % f->size;
906 
907  svm_fifo_trace_add (f, head, len, 2);
908 
909  /* collect out-of-order segments */
910  if (PREDICT_FALSE (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX))
911  {
912  len += ooo_segment_try_collect (f, len, &tail);
913  if (!svm_fifo_chunk_includes_pos (f->tail_chunk, tail))
914  f->tail_chunk = svm_fifo_find_chunk (f, tail);
915  }
916 
917  /* store-rel: producer owned index (paired with load-acq in consumer) */
918  clib_atomic_store_rel_n (&f->tail, tail);
919 
920  return len;
921 }
922 
923 /**
924  * Enqueue a future segment.
925  *
926  * Two choices: either copies the entire segment, or copies nothing
927  * Returns 0 of the entire segment was copied
928  * Returns -1 if none of the segment was copied due to lack of space
929  */
930 int
932 {
933  u32 tail, head, free_count, tail_idx;
934 
935  f_load_head_tail_prod (f, &head, &tail);
936 
937  if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SHRINK))
938  svm_fifo_try_shrink (f, head, tail);
939 
940  /* free space in fifo can only increase during enqueue: SPSC */
941  free_count = f_free_count (f, head, tail);
942 
943  /* will this request fit? */
944  if ((len + offset) > free_count)
945  return SVM_FIFO_EFULL;
946 
947  f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
948  svm_fifo_trace_add (f, offset, len, 1);
949  ooo_segment_add (f, offset, head, tail, len);
950  tail_idx = (tail + offset) % f->size;
951 
952  if (!svm_fifo_chunk_includes_pos (f->ooo_enq, tail_idx))
953  f->ooo_enq = svm_fifo_find_chunk (f, tail_idx);
954 
955  svm_fifo_copy_to_chunk (f, f->ooo_enq, tail_idx, src, len, &f->ooo_enq);
956 
957  return 0;
958 }
959 
960 /**
961  * Advance tail
962  */
963 void
965 {
966  u32 tail;
967 
968  ASSERT (len <= svm_fifo_max_enqueue_prod (f));
969  /* load-relaxed: producer owned index */
970  tail = f->tail;
971  tail = (tail + len) % f->size;
972 
973  if (!svm_fifo_chunk_includes_pos (f->tail_chunk, tail))
974  f->tail_chunk = svm_fifo_find_chunk (f, tail);
975 
976  /* store-rel: producer owned index (paired with load-acq in consumer) */
977  clib_atomic_store_rel_n (&f->tail, tail);
978 }
979 
980 int
982 {
983  u32 tail, head, cursize;
984 
985  f_load_head_tail_cons (f, &head, &tail);
986 
987  /* current size of fifo can only increase during dequeue: SPSC */
988  cursize = f_cursize (f, head, tail);
989 
990  if (PREDICT_FALSE (cursize == 0))
991  return SVM_FIFO_EEMPTY;
992 
993  len = clib_min (cursize, len);
994  svm_fifo_copy_from_chunk (f, f->head_chunk, head, dst, len, &f->head_chunk);
995  head = (head + len) % f->size;
996 
997  if (PREDICT_FALSE (f->flags & SVM_FIFO_F_GROW))
998  svm_fifo_try_grow (f, head);
999 
1000  /* store-rel: consumer owned index (paired with load-acq in producer) */
1001  clib_atomic_store_rel_n (&f->head, head);
1002 
1003  return len;
1004 }
1005 
1006 int
1008 {
1009  u32 tail, head, cursize, head_idx;
1010 
1011  f_load_head_tail_cons (f, &head, &tail);
1012 
1013  /* current size of fifo can only increase during peek: SPSC */
1014  cursize = f_cursize (f, head, tail);
1015 
1016  if (PREDICT_FALSE (cursize < offset))
1017  return SVM_FIFO_EEMPTY;
1018 
1019  len = clib_min (cursize - offset, len);
1020  head_idx = (head + offset) % f->size;
1021  if (!svm_fifo_chunk_includes_pos (f->ooo_deq, head_idx))
1022  f->ooo_deq = svm_fifo_find_chunk (f, head_idx);
1023 
1024  svm_fifo_copy_from_chunk (f, f->ooo_deq, head_idx, dst, len, &f->ooo_deq);
1025  return len;
1026 }
1027 
1028 int
1030 {
1031  u32 total_drop_bytes, tail, head, cursize;
1032 
1033  f_load_head_tail_cons (f, &head, &tail);
1034 
1035  /* number of bytes available */
1036  cursize = f_cursize (f, head, tail);
1037  if (PREDICT_FALSE (cursize == 0))
1038  return SVM_FIFO_EEMPTY;
1039 
1040  /* number of bytes we're going to drop */
1041  total_drop_bytes = clib_min (cursize, len);
1042 
1043  svm_fifo_trace_add (f, tail, total_drop_bytes, 3);
1044 
1045  /* move head */
1046  head = (head + total_drop_bytes) % f->size;
1047 
1048  if (!svm_fifo_chunk_includes_pos (f->head_chunk, head))
1049  f->head_chunk = svm_fifo_find_chunk (f, head);
1050 
1051  if (PREDICT_FALSE (f->flags & SVM_FIFO_F_GROW))
1052  svm_fifo_try_grow (f, head);
1053 
1054  /* store-rel: consumer owned index (paired with load-acq in producer) */
1055  clib_atomic_store_rel_n (&f->head, head);
1056 
1057  return total_drop_bytes;
1058 }
1059 
1060 void
1062 {
1063  /* consumer foreign index */
1064  u32 tail = clib_atomic_load_acq_n (&f->tail);
1065 
1066  if (!svm_fifo_chunk_includes_pos (f->head_chunk, tail))
1067  f->head_chunk = svm_fifo_find_chunk (f, tail);
1068 
1069  if (PREDICT_FALSE (f->flags & SVM_FIFO_F_GROW))
1070  svm_fifo_try_grow (f, tail);
1071 
1072  /* store-rel: consumer owned index (paired with load-acq in producer) */
1073  clib_atomic_store_rel_n (&f->head, tail);
1074 }
1075 
1076 int
1078 {
1079  u32 cursize, head, tail, head_idx;
1080 
1081  f_load_head_tail_cons (f, &head, &tail);
1082 
1083  /* consumer function, cursize can only increase while we're working */
1084  cursize = f_cursize (f, head, tail);
1085 
1086  if (PREDICT_FALSE (cursize == 0))
1087  return SVM_FIFO_EEMPTY;
1088 
1089  head_idx = head;
1090 
1091  if (tail < head)
1092  {
1093  fs[0].len = f->size - head_idx;
1094  fs[0].data = f->head_chunk->data + head_idx;
1095  fs[1].len = cursize - fs[0].len;
1096  fs[1].data = f->head_chunk->data;
1097  }
1098  else
1099  {
1100  fs[0].len = cursize;
1101  fs[0].data = f->head_chunk->data + head_idx;
1102  fs[1].len = 0;
1103  fs[1].data = 0;
1104  }
1105  return cursize;
1106 }
1107 
1108 void
1110 {
1111  u32 head;
1112 
1113  /* consumer owned index */
1114  head = f->head;
1115 
1116  ASSERT (fs[0].data == f->head_chunk->data + head);
1117  head = (head + fs[0].len + fs[1].len) % f->size;
1118  /* store-rel: consumer owned index (paired with load-acq in producer) */
1119  clib_atomic_store_rel_n (&f->head, head);
1120 }
1121 
1122 /**
1123  * Clones fifo
1124  *
1125  * Assumptions:
1126  * - no prod and cons are accessing either dest or src fifo
1127  * - fifo is not multi chunk
1128  */
1129 void
1131 {
1132  u32 head, tail;
1133  clib_memcpy_fast (df->head_chunk->data, sf->head_chunk->data, sf->size);
1134 
1135  f_load_head_tail_all_acq (sf, &head, &tail);
1136  clib_atomic_store_rel_n (&df->head, head);
1137  clib_atomic_store_rel_n (&df->tail, tail);
1138 }
1139 
1140 u32
1142 {
1143  return pool_elts (f->ooo_segments);
1144 }
1145 
1146 ooo_segment_t *
1148 {
1149  return pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
1150 }
1151 
1152 /**
1153  * Set fifo pointers to requested offset
1154  */
1155 void
1157 {
1158  head = head % f->size;
1159  tail = tail % f->size;
1160  clib_atomic_store_rel_n (&f->head, head);
1161  clib_atomic_store_rel_n (&f->tail, tail);
1162  if (f->flags & SVM_FIFO_F_MULTI_CHUNK)
1163  {
1165  c = svm_fifo_find_chunk (f, head);
1166  ASSERT (c != 0);
1167  f->head_chunk = f->ooo_deq = c;
1168  c = svm_fifo_find_chunk (f, tail);
1169  ASSERT (c != 0);
1170  f->tail_chunk = f->ooo_enq = c;
1171  }
1172 }
1173 
1174 void
1176 {
1177  if (f->n_subscribers >= SVM_FIFO_MAX_EVT_SUBSCRIBERS)
1178  return;
1179  f->subscribers[f->n_subscribers++] = subscriber;
1180 }
1181 
1182 void
1184 {
1185  int i;
1186 
1187  for (i = 0; i < f->n_subscribers; i++)
1188  {
1189  if (f->subscribers[i] != subscriber)
1190  continue;
1191  f->subscribers[i] = f->subscribers[f->n_subscribers - 1];
1192  f->n_subscribers--;
1193  break;
1194  }
1195 }
1196 
1197 u8
1199 {
1200  if (f->size - 1 != f->nitems && !(f->flags & SVM_FIFO_F_SHRINK))
1201  return 0;
1202  if (!svm_fifo_chunk_includes_pos (f->head_chunk, f->head))
1203  return 0;
1204  if (!svm_fifo_chunk_includes_pos (f->tail_chunk, f->tail))
1205  return 0;
1206 
1207  if (f->start_chunk->next != f->start_chunk)
1208  {
1209  svm_fifo_chunk_t *c, *prev = 0, *tmp;
1210  u32 size = 0;
1211 
1212  if (!(f->flags & SVM_FIFO_F_MULTI_CHUNK))
1213  return 0;
1214 
1215  c = f->start_chunk;
1216  do
1217  {
1218  tmp = svm_fifo_find_chunk (f, c->start_byte);
1219  if (tmp != c)
1220  return 0;
1221  if (prev && (prev->start_byte + prev->length != c->start_byte))
1222  return 0;
1223  size += c->length;
1224  prev = c;
1225  c = c->next;
1226  }
1227  while (c != f->start_chunk);
1228 
1229  if (size != f->size)
1230  return 0;
1231  }
1232 
1233  return 1;
1234 }
1235 
1236 u8
1238 {
1239  if (f->flags & SVM_FIFO_F_SINGLE_THREAD_OWNED)
1240  {
1241  if (f->master_thread_index == os_get_thread_index ())
1242  {
1243  /* just a duplicate call */
1244  return 0;
1245  }
1246 
1247  /* already owned by another thread */
1248  return 1;
1249  }
1250 
1251  f->flags |= SVM_FIFO_F_SINGLE_THREAD_OWNED;
1252  return 0;
1253 }
1254 
1255 u8 *
1256 format_ooo_segment (u8 * s, va_list * args)
1257 {
1258  svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
1259  ooo_segment_t *seg = va_arg (*args, ooo_segment_t *);
1260  u32 normalized_start = (seg->start + f->nitems - f->tail) % f->size;
1261  s = format (s, "[%u, %u], len %u, next %d, prev %d", normalized_start,
1262  (normalized_start + seg->length) % f->size, seg->length,
1263  seg->next, seg->prev);
1264  return s;
1265 }
1266 
1267 u8 *
1269 {
1270 #if SVM_FIFO_TRACE
1271  svm_fifo_trace_elem_t *seg = 0;
1272  int i = 0;
1273 
1274  if (f->trace)
1275  {
1276  vec_foreach (seg, f->trace)
1277  {
1278  s = format (s, "{%u, %u, %u}, ", seg->offset, seg->len, seg->action);
1279  i++;
1280  if (i % 5 == 0)
1281  s = format (s, "\n");
1282  }
1283  s = format (s, "\n");
1284  }
1285  return s;
1286 #else
1287  return 0;
1288 #endif
1289 }
1290 
1291 u8 *
1292 svm_fifo_replay (u8 * s, svm_fifo_t * f, u8 no_read, u8 verbose)
1293 {
1294  int i, trace_len;
1295  u8 *data = 0;
1297  u32 offset;
1298  svm_fifo_t *dummy_fifo;
1299 
1300  if (!f)
1301  return s;
1302 
1303 #if SVM_FIFO_TRACE
1304  trace = f->trace;
1305  trace_len = vec_len (trace);
1306 #else
1307  trace = 0;
1308  trace_len = 0;
1309 #endif
1310 
1311  dummy_fifo = svm_fifo_create (f->size);
1312  clib_memset (f->head_chunk->data, 0xFF, f->nitems);
1313  vec_validate (data, f->nitems);
1314  for (i = 0; i < vec_len (data); i++)
1315  data[i] = i;
1316 
1317  for (i = 0; i < trace_len; i++)
1318  {
1319  offset = trace[i].offset;
1320  if (trace[i].action == 1)
1321  {
1322  if (verbose)
1323  s = format (s, "adding [%u, %u]:", trace[i].offset,
1324  (trace[i].offset + trace[i].len) % dummy_fifo->size);
1325  svm_fifo_enqueue_with_offset (dummy_fifo, trace[i].offset,
1326  trace[i].len, &data[offset]);
1327  }
1328  else if (trace[i].action == 2)
1329  {
1330  if (verbose)
1331  s = format (s, "adding [%u, %u]:", 0, trace[i].len);
1332  svm_fifo_enqueue (dummy_fifo, trace[i].len, &data[offset]);
1333  }
1334  else if (!no_read)
1335  {
1336  if (verbose)
1337  s = format (s, "read: %u", trace[i].len);
1338  svm_fifo_dequeue_drop (dummy_fifo, trace[i].len);
1339  }
1340  if (verbose)
1341  s = format (s, "%U", format_svm_fifo, dummy_fifo, 1);
1342  }
1343 
1344  s = format (s, "result: %U", format_svm_fifo, dummy_fifo, 1);
1345 
1346  return s;
1347 }
1348 
1349 u8 *
1350 format_ooo_list (u8 * s, va_list * args)
1351 {
1352  svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
1353  u32 indent = va_arg (*args, u32);
1354  u32 ooo_segment_index = f->ooos_list_head;
1355  ooo_segment_t *seg;
1356 
1357  while (ooo_segment_index != OOO_SEGMENT_INVALID_INDEX)
1358  {
1359  seg = pool_elt_at_index (f->ooo_segments, ooo_segment_index);
1360  s = format (s, "%U%U\n", format_white_space, indent, format_ooo_segment,
1361  f, seg);
1362  ooo_segment_index = seg->next;
1363  }
1364 
1365  return s;
1366 }
1367 
1368 u8 *
1369 format_svm_fifo (u8 * s, va_list * args)
1370 {
1371  svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
1372  int verbose = va_arg (*args, int);
1373  u32 indent;
1374 
1375  if (!s)
1376  return s;
1377 
1378  indent = format_get_indent (s);
1379  s = format (s, "cursize %u nitems %u has_event %d\n",
1380  svm_fifo_max_dequeue (f), f->nitems, f->has_event);
1381  s = format (s, "%Uhead %u tail %u segment manager %u\n", format_white_space,
1382  indent, (f->head % f->size), (f->tail % f->size),
1383  f->segment_manager);
1384 
1385  if (verbose > 1)
1386  s = format (s, "%Uvpp session %d thread %d app session %d thread %d\n",
1387  format_white_space, indent, f->master_session_index,
1388  f->master_thread_index, f->client_session_index,
1389  f->client_thread_index);
1390 
1391  if (verbose)
1392  {
1393  s = format (s, "%Uooo pool %d active elts newest %u\n",
1394  format_white_space, indent, pool_elts (f->ooo_segments),
1395  f->ooos_newest);
1396  if (svm_fifo_has_ooo_data (f))
1397  s = format (s, " %U", format_ooo_list, f, indent, verbose);
1398  }
1399  return s;
1400 }
1401 
1402 #endif
1403 /*
1404  * fd.io coding-style-patch-verification: ON
1405  *
1406  * Local Variables:
1407  * eval: (c-set-style "gnu")
1408  * End:
1409  */
u32 length
length of chunk in bytes
Definition: svm_fifo.h:61
#define vec_validate(V, I)
Make sure vector is long enough for given index (no header, unspecified alignment) ...
Definition: vec.h:440
static void svm_fifo_copy_to_chunk(svm_fifo_t *f, svm_fifo_chunk_t *c, u32 tail_idx, const u8 *src, u32 len, svm_fifo_chunk_t **last)
Definition: svm_fifo.c:86
rb_node_t * rb_tree_predecessor(rb_tree_t *rt, rb_node_t *x)
Definition: rbtree.c:286
static void f_load_head_tail_all_acq(svm_fifo_t *f, u32 *head, u32 *tail)
Load head and tail independent of producer/consumer role.
Definition: svm_fifo.h:185
static vlib_cli_command_t trace
(constructor) VLIB_CLI_COMMAND (trace)
Definition: vlib_api_cli.c:898
#define clib_min(x, y)
Definition: clib.h:295
svm_fifo_chunk_t * svm_fifo_collect_chunks(svm_fifo_t *f)
Removes chunks that are after fifo end byte.
Definition: svm_fifo.c:715
static int ooo_segment_try_collect(svm_fifo_t *f, u32 n_bytes_enqueued, u32 *tail)
Removes segments that can now be enqueued because the fifo&#39;s tail has advanced.
Definition: svm_fifo.c:330
int svm_fifo_segments(svm_fifo_t *f, svm_fifo_seg_t *fs)
Definition: svm_fifo.c:1077
static u32 svm_fifo_max_enqueue_prod(svm_fifo_t *f)
Maximum number of bytes that can be enqueued into fifo.
Definition: svm_fifo.h:619
a
Definition: bitmap.h:538
static ooo_segment_t * ooo_segment_next(svm_fifo_t *f, ooo_segment_t *s)
Definition: svm_fifo.c:146
int flags
Definition: svmdb.h:67
static rb_node_t * rb_node_left(rb_tree_t *rt, rb_node_t *n)
Definition: rbtree.h:92
void svm_fifo_free_chunk_lookup(svm_fifo_t *f)
Cleanup fifo chunk lookup rb tree.
Definition: svm_fifo.c:847
static u8 svm_fifo_has_ooo_data(svm_fifo_t *f)
Check if fifo has out-of-order data.
Definition: svm_fifo.h:693
void svm_fifo_init_pointers(svm_fifo_t *f, u32 head, u32 tail)
Set fifo pointers to requested offset.
Definition: svm_fifo.c:1156
static u32 f_free_count(svm_fifo_t *f, u32 head, u32 tail)
Fifo free bytes, i.e., number of free bytes.
Definition: svm_fifo.h:232
void svm_fifo_segments_free(svm_fifo_t *f, svm_fifo_seg_t *fs)
Definition: svm_fifo.c:1109
static u8 position_leq(svm_fifo_t *f, u32 a, u32 b, u32 tail)
Definition: svm_fifo.c:108
void svm_fifo_free(svm_fifo_t *f)
Free fifo and associated state.
Definition: svm_fifo.c:853
#define clib_memcpy_fast(a, b, c)
Definition: string.h:81
u32 prev
Previous linked-list element pool index.
Definition: svm_fifo.h:32
clib_memset(h->entries, 0, sizeof(h->entries[0]) *entries)
static void f_load_head_tail_cons(svm_fifo_t *f, u32 *head, u32 *tail)
Load head and tail optimized for consumer.
Definition: svm_fifo.h:158
static u8 position_gt(svm_fifo_t *f, u32 a, u32 b, u32 tail)
Definition: svm_fifo.c:114
static void svm_fifo_copy_from_chunk(svm_fifo_t *f, svm_fifo_chunk_t *c, u32 head_idx, u8 *dst, u32 len, svm_fifo_chunk_t **last)
Definition: svm_fifo.c:94
#define CLIB_MARCH_FN_SELECT(fn)
Definition: cpu.h:387
vl_api_address_t src
Definition: gre.api:60
static heap_elt_t * last(heap_header_t *h)
Definition: heap.c:53
int svm_fifo_peek(svm_fifo_t *f, u32 offset, u32 len, u8 *dst)
Peek data from fifo.
Definition: svm_fifo.c:1007
void svm_fifo_enqueue_nocopy(svm_fifo_t *f, u32 len)
Advance tail.
Definition: svm_fifo.c:964
void svm_fifo_init(svm_fifo_t *f, u32 size)
Initialize fifo.
Definition: svm_fifo.c:392
int i
static rb_node_t * rb_node(rb_tree_t *rt, rb_node_index_t ri)
Definition: rbtree.h:80
static u32 format_get_indent(u8 *s)
Definition: format.h:72
ooo_segment_t * svm_fifo_first_ooo_segment(svm_fifo_t *f)
First out-of-order segment for fifo.
Definition: svm_fifo.c:1147
void svm_fifo_dequeue_drop_all(svm_fifo_t *f)
Dequeue and drop all bytes from fifo.
Definition: svm_fifo.c:1061
static ooo_segment_t * ooo_segment_last(svm_fifo_t *f)
Definition: svm_fifo.c:378
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:424
static rb_node_t * rb_node_right(rb_tree_t *rt, rb_node_t *n)
Definition: rbtree.h:86
void svm_fifo_overwrite_head(svm_fifo_t *f, u8 *src, u32 len)
Overwrite fifo head with new data.
Definition: svm_fifo.c:866
#define SVM_FIFO_INVALID_INDEX
Definition: svm_fifo.h:40
void rb_tree_free_nodes(rb_tree_t *rt)
Definition: rbtree.c:474
#define pool_get(P, E)
Allocate an object E from a pool P (unspecified alignment).
Definition: pool.h:237
unsigned char u8
Definition: types.h:56
rb_node_index_t rb_tree_add2(rb_tree_t *rt, u32 key, uword opaque)
Definition: rbtree.c:182
u8 svm_fifo_set_single_thread_owned(svm_fifo_t *f)
Declare this fifo is used by only a single thread.
Definition: svm_fifo.c:1237
struct _svm_fifo svm_fifo_t
void svm_fifo_init_chunks(svm_fifo_t *f)
Initialize fifo chunks and rbtree.
Definition: svm_fifo.c:408
static ooo_segment_t * ooo_segment_alloc(svm_fifo_t *f, u32 start, u32 length)
Definition: svm_fifo.c:154
static svm_fifo_chunk_t * svm_fifo_find_chunk(svm_fifo_t *f, u32 pos)
Find chunk for given byte position.
Definition: svm_fifo.c:503
void svm_fifo_clone(svm_fifo_t *df, svm_fifo_t *sf)
Clones fifo.
Definition: svm_fifo.c:1130
static u32 svm_fifo_max_dequeue(svm_fifo_t *f)
Fifo max bytes to dequeue.
Definition: svm_fifo.h:528
u8 * format_white_space(u8 *s, va_list *va)
Definition: std-formats.c:129
svm_fifo_chunk_t * svm_fifo_chunk_alloc(u32 size)
Creates a fifo chunk in the current heap.
Definition: svm_fifo.c:471
u8 * format_ooo_list(u8 *s, va_list *args)
Definition: svm_fifo.c:1350
void svm_fifo_free_ooo_data(svm_fifo_t *f)
Cleanup fifo ooo data.
Definition: svm_fifo.c:132
static void ooo_segment_free(svm_fifo_t *f, u32 index)
Definition: svm_fifo.c:168
unsigned int u32
Definition: types.h:88
int svm_fifo_dequeue(svm_fifo_t *f, u32 len, u8 *dst)
Dequeue data from fifo.
Definition: svm_fifo.c:981
u32 key
node key
Definition: rbtree.h:38
void rb_tree_del(rb_tree_t *rt, u32 key)
Definition: rbtree.c:444
#define pool_elt_at_index(p, i)
Returns pointer to element at given index.
Definition: pool.h:519
uword opaque
value stored by node
Definition: rbtree.h:39
static ooo_segment_t * ooo_segment_prev(svm_fifo_t *f, ooo_segment_t *s)
Definition: svm_fifo.c:138
struct svm_fifo_chunk_ * next
pointer to next chunk in linked-lists
Definition: svm_fifo.h:62
static void svm_fifo_grow(svm_fifo_t *f, svm_fifo_chunk_t *c)
Definition: svm_fifo.c:546
u64 size
Definition: vhost_user.h:140
#define pool_put(P, E)
Free an object E in pool P.
Definition: pool.h:287
int svm_fifo_enqueue(svm_fifo_t *f, u32 len, const u8 *src)
Enqueue data to fifo.
Definition: svm_fifo.c:888
#define PREDICT_FALSE(x)
Definition: clib.h:111
void rb_tree_init(rb_tree_t *rt)
Definition: rbtree.c:481
#define svm_fifo_trace_add(_f, _s, _l, _t)
Definition: svm_fifo.h:146
vl_api_address_t dst
Definition: gre.api:61
u8 * svm_fifo_replay(u8 *s, svm_fifo_t *f, u8 no_read, u8 verbose)
Definition: svm_fifo.c:1292
CLIB_MARCH_FN(svm_fifo_copy_to_chunk, void, svm_fifo_t *f, svm_fifo_chunk_t *c, u32 tail_idx, const u8 *src, u32 len, svm_fifo_chunk_t **last)
Definition: svm_fifo.c:23
u8 len
Definition: ip_types.api:91
void svm_fifo_add_subscriber(svm_fifo_t *f, u8 subscriber)
Add io events subscriber to list.
Definition: svm_fifo.c:1175
#define pool_free(p)
Free a pool.
Definition: pool.h:412
#define SVM_FIFO_MAX_EVT_SUBSCRIBERS
Definition: svm_fifo.h:41
svmdb_client_t * c
static u32 f_cursize(svm_fifo_t *f, u32 head, u32 tail)
Fifo current size, i.e., number of bytes enqueued.
Definition: svm_fifo.h:221
static u32 position_diff(svm_fifo_t *f, u32 a, u32 b, u32 tail)
Definition: svm_fifo.c:120
int svm_fifo_reduce_size(svm_fifo_t *f, u32 len, u8 try_shrink)
Request to reduce fifo size by amount of bytes.
Definition: svm_fifo.c:807
void svm_fifo_add_chunk(svm_fifo_t *f, svm_fifo_chunk_t *c)
Grow fifo size by adding chunk to chunk list.
Definition: svm_fifo.c:579
static void f_load_head_tail_prod(svm_fifo_t *f, u32 *head, u32 *tail)
Load head and tail optimized for producer.
Definition: svm_fifo.h:171
u32 start_byte
chunk start byte
Definition: svm_fifo.h:60
u8 svm_fifo_is_sane(svm_fifo_t *f)
Check if fifo is sane.
Definition: svm_fifo.c:1198
#define OOO_SEGMENT_INVALID_INDEX
Definition: svm_fifo.h:38
u8 * format_ooo_segment(u8 *s, va_list *args)
Definition: svm_fifo.c:1256
u32 svm_fifo_n_ooo_segments(svm_fifo_t *f)
Number of out-of-order segments for fifo.
Definition: svm_fifo.c:1141
static void * clib_mem_alloc_aligned_or_null(uword size, uword align)
Definition: mem.h:177
signed int i32
Definition: types.h:77
#define uword_to_pointer(u, type)
Definition: types.h:136
u8 * format_svm_fifo(u8 *s, va_list *args)
Definition: svm_fifo.c:1369
#define ASSERT(truth)
u8 data[128]
Definition: ipsec_types.api:87
static void clib_mem_free(void *p)
Definition: mem.h:226
u8 data[0]
start of chunk data
Definition: svm_fifo.h:63
void svm_fifo_del_subscriber(svm_fifo_t *f, u8 subscriber)
Remove io events subscriber form list.
Definition: svm_fifo.c:1183
int svm_fifo_enqueue_with_offset(svm_fifo_t *f, u32 offset, u32 len, u8 *src)
Enqueue a future segment.
Definition: svm_fifo.c:931
static u8 svm_fifo_is_wrapped(svm_fifo_t *f)
Check if fifo is wrapped.
Definition: svm_fifo.h:603
Out-of-order segment.
Definition: svm_fifo.h:29
static uword pointer_to_uword(const void *p)
Definition: types.h:131
static u8 svm_fifo_chunk_includes_pos(svm_fifo_chunk_t *c, u32 pos)
Definition: svm_fifo.c:489
#define clib_atomic_store_rel_n(a, b)
Definition: atomics.h:49
#define clib_max(x, y)
Definition: clib.h:288
static u32 f_distance_to(svm_fifo_t *f, u32 a, u32 b)
Distance to a from b, i.e., a - b in the fifo.
Definition: svm_fifo.h:199
u32 length
Length of segment.
Definition: svm_fifo.h:34
u8 * svm_fifo_dump_trace(u8 *s, svm_fifo_t *f)
Definition: svm_fifo.c:1268
typedef key
Definition: ipsec_types.api:83
u32 next
Next linked-list element pool index.
Definition: svm_fifo.h:31
template key/value backing page structure
Definition: bihash_doc.h:44
static u8 rb_node_is_tnil(rb_tree_t *rt, rb_node_t *n)
Definition: rbtree.h:74
static u32 ooo_segment_end_pos(svm_fifo_t *f, ooo_segment_t *s)
Definition: svm_fifo.c:126
u8 action
Definition: l2.api:173
#define vec_len(v)
Number of elements in vector (rvalue-only, NULL tolerant)
static uword max_log2(uword x)
Definition: clib.h:191
static void svm_fifo_try_grow(svm_fifo_t *f, u32 new_head)
Definition: svm_fifo.c:569
static u32 f_distance_from(svm_fifo_t *f, u32 a, u32 b)
Distance from a to b, i.e., b - a in the fifo.
Definition: svm_fifo.h:210
static_always_inline uword os_get_thread_index(void)
Definition: os.h:62
void svm_fifo_try_shrink(svm_fifo_t *f, u32 head, u32 tail)
Try to shrink fifo size.
Definition: svm_fifo.c:734
struct clib_bihash_value offset
template key/value backing page structure
#define vec_foreach(var, vec)
Vector iterator.
static u8 position_lt(svm_fifo_t *f, u32 a, u32 b, u32 tail)
Definition: svm_fifo.c:102
#define CLIB_CACHE_LINE_BYTES
Definition: cache.h:59
#define clib_atomic_load_acq_n(a)
Definition: atomics.h:48
int svm_fifo_dequeue_drop(svm_fifo_t *f, u32 len)
Dequeue and drop bytes from fifo.
Definition: svm_fifo.c:1029
rb_node_index_t root
root index
Definition: rbtree.h:45
u32 start
Start of segment, normalized.
Definition: svm_fifo.h:33
static void ooo_segment_add(svm_fifo_t *f, u32 offset, u32 head, u32 tail, u32 length)
Add segment to fifo&#39;s out-of-order segment list.
Definition: svm_fifo.c:197
svm_fifo_t * svm_fifo_create(u32 data_size_in_bytes)
Creates a fifo in the current heap.
Definition: svm_fifo.c:436
static uword pool_elts(void *v)
Number of active elements in a pool.
Definition: pool.h:128