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:
11 * http://www.apache.org/licenses/LICENSE-2.0
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.
20 #include <svm/svm_fifo.h>
21 #include <svm/fifo_segment.h>
22 #include <vppinfra/cpu.h>
24 CLIB_MARCH_FN (svm_fifo_copy_to_chunk, void, svm_fifo_t * f,
25 svm_fifo_chunk_t * c, u32 tail_idx, const u8 * src, u32 len,
26 svm_fifo_chunk_t ** last)
30 ASSERT (f_pos_geq (tail_idx, c->start_byte)
31 && f_pos_lt (tail_idx, c->start_byte + c->length));
33 tail_idx -= c->start_byte;
34 n_chunk = c->length - tail_idx;
38 clib_memcpy_fast (&c->data[tail_idx], src, n_chunk);
40 while ((to_copy -= n_chunk))
42 n_chunk = clib_min (c->length, to_copy);
43 clib_memcpy_fast (&c->data[0], src + (len - to_copy), n_chunk);
44 c = c->length <= to_copy ? c->next : c;
51 clib_memcpy_fast (&c->data[tail_idx], src, len);
55 CLIB_MARCH_FN (svm_fifo_copy_from_chunk, void, svm_fifo_t * f,
56 svm_fifo_chunk_t * c, u32 head_idx, u8 * dst, u32 len,
57 svm_fifo_chunk_t ** last)
61 ASSERT (f_pos_geq (head_idx, c->start_byte)
62 && f_pos_lt (head_idx, c->start_byte + c->length));
64 head_idx -= c->start_byte;
65 n_chunk = c->length - head_idx;
69 clib_memcpy_fast (dst, &c->data[head_idx], n_chunk);
71 while ((to_copy -= n_chunk))
73 n_chunk = clib_min (c->length, to_copy);
74 clib_memcpy_fast (dst + (len - to_copy), &c->data[0], n_chunk);
75 c = c->length <= to_copy ? c->next : c;
82 clib_memcpy_fast (dst, &c->data[head_idx], len);
86 #ifndef CLIB_MARCH_VARIANT
89 svm_fifo_copy_to_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c, u32 tail_idx,
90 const u8 * src, u32 len, svm_fifo_chunk_t ** last)
92 CLIB_MARCH_FN_SELECT (svm_fifo_copy_to_chunk) (f, c, tail_idx, src, len,
97 svm_fifo_copy_from_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c, u32 head_idx,
98 u8 * dst, u32 len, svm_fifo_chunk_t ** last)
100 CLIB_MARCH_FN_SELECT (svm_fifo_copy_from_chunk) (f, c, head_idx, dst, len,
105 ooo_segment_end_pos (ooo_segment_t * s)
107 return (s->start + s->length);
111 svm_fifo_free_ooo_data (svm_fifo_t * f)
113 pool_free (f->ooo_segments);
116 static inline ooo_segment_t *
117 ooo_segment_prev (svm_fifo_t * f, ooo_segment_t * s)
119 if (s->prev == OOO_SEGMENT_INVALID_INDEX)
121 return pool_elt_at_index (f->ooo_segments, s->prev);
124 static inline ooo_segment_t *
125 ooo_segment_next (svm_fifo_t * f, ooo_segment_t * s)
127 if (s->next == OOO_SEGMENT_INVALID_INDEX)
129 return pool_elt_at_index (f->ooo_segments, s->next);
132 static inline ooo_segment_t *
133 ooo_segment_alloc (svm_fifo_t * f, u32 start, u32 length)
137 pool_get (f->ooo_segments, s);
141 s->prev = s->next = OOO_SEGMENT_INVALID_INDEX;
147 ooo_segment_free (svm_fifo_t * f, u32 index)
149 ooo_segment_t *cur, *prev = 0, *next = 0;
150 cur = pool_elt_at_index (f->ooo_segments, index);
152 if (cur->next != OOO_SEGMENT_INVALID_INDEX)
154 next = pool_elt_at_index (f->ooo_segments, cur->next);
155 next->prev = cur->prev;
158 if (cur->prev != OOO_SEGMENT_INVALID_INDEX)
160 prev = pool_elt_at_index (f->ooo_segments, cur->prev);
161 prev->next = cur->next;
165 f->ooos_list_head = cur->next;
168 pool_put (f->ooo_segments, cur);
172 * Add segment to fifo's out-of-order segment list. Takes care of merging
173 * adjacent segments and removing overlapping ones.
176 ooo_segment_add (svm_fifo_t * f, u32 offset, u32 head, u32 tail, u32 length)
178 ooo_segment_t *s, *new_s, *prev, *next, *it;
179 u32 new_index, s_end_pos, s_index;
180 u32 offset_pos, offset_end_pos;
182 ASSERT (offset + length <= f_free_count (f, head, tail));
184 offset_pos = tail + offset;
185 offset_end_pos = tail + offset + length;
187 f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
189 if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
191 s = ooo_segment_alloc (f, offset_pos, length);
192 f->ooos_list_head = s - f->ooo_segments;
193 f->ooos_newest = f->ooos_list_head;
197 /* Find first segment that starts after new segment */
198 s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
199 while (s->next != OOO_SEGMENT_INVALID_INDEX
200 && f_pos_lt (s->start, offset_pos))
201 s = pool_elt_at_index (f->ooo_segments, s->next);
203 /* If we have a previous and we overlap it, use it as starting point */
204 prev = ooo_segment_prev (f, s);
205 if (prev && f_pos_leq (offset_pos, ooo_segment_end_pos (prev)))
208 s_end_pos = ooo_segment_end_pos (s);
210 /* Since we have previous, offset start position cannot be smaller
211 * than prev->start. Check tail */
212 ASSERT (f_pos_lt (s->start, offset_pos));
216 s_index = s - f->ooo_segments;
217 s_end_pos = ooo_segment_end_pos (s);
219 /* No overlap, add before current segment */
220 if (f_pos_lt (offset_end_pos, s->start))
222 new_s = ooo_segment_alloc (f, offset_pos, length);
223 new_index = new_s - f->ooo_segments;
225 /* Pool might've moved, get segment again */
226 s = pool_elt_at_index (f->ooo_segments, s_index);
227 if (s->prev != OOO_SEGMENT_INVALID_INDEX)
229 new_s->prev = s->prev;
230 prev = pool_elt_at_index (f->ooo_segments, new_s->prev);
231 prev->next = new_index;
236 f->ooos_list_head = new_index;
239 new_s->next = s_index;
241 f->ooos_newest = new_index;
244 /* No overlap, add after current segment */
245 else if (f_pos_gt (offset_pos, s_end_pos))
247 new_s = ooo_segment_alloc (f, offset_pos, length);
248 new_index = new_s - f->ooo_segments;
250 /* Pool might've moved, get segment again */
251 s = pool_elt_at_index (f->ooo_segments, s_index);
253 /* Needs to be last */
254 ASSERT (s->next == OOO_SEGMENT_INVALID_INDEX);
256 new_s->prev = s_index;
258 f->ooos_newest = new_index;
268 if (f_pos_lt (offset_pos, s->start))
270 s->start = offset_pos;
271 s->length = s_end_pos - s->start;
272 f->ooos_newest = s - f->ooo_segments;
277 /* Overlapping tail */
278 if (f_pos_gt (offset_end_pos, s_end_pos))
280 s->length = offset_end_pos - s->start;
282 /* Remove the completely overlapped segments in the tail */
283 it = ooo_segment_next (f, s);
284 while (it && f_pos_leq (ooo_segment_end_pos (it), offset_end_pos))
286 next = ooo_segment_next (f, it);
287 ooo_segment_free (f, it - f->ooo_segments);
291 /* If partial overlap with last, merge */
292 if (it && f_pos_leq (it->start, offset_end_pos))
294 s->length = ooo_segment_end_pos (it) - s->start;
295 ooo_segment_free (f, it - f->ooo_segments);
297 f->ooos_newest = s - f->ooo_segments;
302 * Removes segments that can now be enqueued because the fifo's tail has
303 * advanced. Returns the number of bytes added to tail.
306 ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail)
308 u32 s_index, bytes = 0;
312 s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
313 diff = *tail - s->start;
315 ASSERT (diff != n_bytes_enqueued);
317 if (diff > n_bytes_enqueued)
320 /* If last tail update overlaps one/multiple ooo segments, remove them */
321 while (0 <= diff && diff < n_bytes_enqueued)
323 s_index = s - f->ooo_segments;
325 /* Segment end is beyond the tail. Advance tail and remove segment */
326 if (s->length > diff)
328 bytes = s->length - diff;
329 *tail = *tail + bytes;
330 ooo_segment_free (f, s_index);
334 /* If we have next go on */
335 if (s->next != OOO_SEGMENT_INVALID_INDEX)
337 s = pool_elt_at_index (f->ooo_segments, s->next);
338 diff = *tail - s->start;
339 ooo_segment_free (f, s_index);
344 ooo_segment_free (f, s_index);
349 ASSERT (bytes <= f->size);
353 __clib_unused static ooo_segment_t *
354 ooo_segment_last (svm_fifo_t * f)
358 if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
361 s = svm_fifo_first_ooo_segment (f);
362 while (s->next != OOO_SEGMENT_INVALID_INDEX)
363 s = pool_elt_at_index (f->ooo_segments, s->next);
368 svm_fifo_init (svm_fifo_t * f, u32 size)
370 svm_fifo_chunk_t *c, *prev;
371 u32 first_chunk, min_alloc;
374 f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
375 f->segment_index = SVM_FIFO_INVALID_INDEX;
377 f->head = f->tail = f->flags = 0;
378 f->head_chunk = f->tail_chunk = f->start_chunk;
379 f->ooo_deq = f->ooo_enq = 0;
381 first_chunk = f->start_chunk->length;
382 min_alloc = first_chunk > 16 << 10 ? first_chunk >> 2 : 4096;
383 min_alloc = clib_min (first_chunk, 64 << 10);
384 f->min_alloc = min_alloc;
389 f->start_chunk->start_byte = 0;
390 prev = f->start_chunk;
395 c->start_byte = prev->start_byte + prev->length;
402 svm_fifo_init_ooo_lookup (svm_fifo_t * f, u8 ooo_type)
406 ASSERT (!rb_tree_is_init (&f->ooo_enq_lookup));
407 rb_tree_init (&f->ooo_enq_lookup);
411 ASSERT (!rb_tree_is_init (&f->ooo_deq_lookup));
412 rb_tree_init (&f->ooo_deq_lookup);
417 * Creates a fifo in the current heap. Fails vs blow up the process
420 svm_fifo_alloc (u32 data_size_in_bytes)
422 u32 rounded_data_size;
426 f = clib_mem_alloc_aligned_or_null (sizeof (*f), CLIB_CACHE_LINE_BYTES);
430 clib_memset (f, 0, sizeof (*f));
432 /* always round fifo data size to the next highest power-of-two */
433 rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
434 c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_data_size,
435 CLIB_CACHE_LINE_BYTES);
442 clib_memset (c, 0, sizeof (*c));
444 c->length = data_size_in_bytes;
445 c->enq_rb_index = RBTREE_TNIL_INDEX;
446 c->deq_rb_index = RBTREE_TNIL_INDEX;
447 f->start_chunk = f->end_chunk = c;
453 * Creates a fifo chunk in the current heap
456 svm_fifo_chunk_alloc (u32 size)
461 /* round chunk size to the next highest power-of-two */
462 rounded_size = (1 << (max_log2 (size)));
463 c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_size,
464 CLIB_CACHE_LINE_BYTES);
468 clib_memset (c, 0, sizeof (*c));
469 c->length = rounded_size;
474 * Find chunk for given byte position
477 * @param pos normalized position in fifo
479 * @return chunk that includes given position or 0
481 static svm_fifo_chunk_t *
482 svm_fifo_find_chunk (svm_fifo_t * f, u32 pos)
487 while (c && !f_chunk_includes_pos (c, pos))
493 static svm_fifo_chunk_t *
494 svm_fifo_find_next_chunk (svm_fifo_t * f, svm_fifo_chunk_t * start, u32 pos)
501 while (c && !f_chunk_includes_pos (c, pos))
508 svm_fifo_max_read_chunk (svm_fifo_t * f)
510 u32 head, tail, end_chunk;
512 f_load_head_tail_cons (f, &head, &tail);
513 ASSERT (!f->head_chunk || f_chunk_includes_pos (f->head_chunk, head));
517 f->head_chunk = svm_fifo_find_chunk (f, head);
518 if (PREDICT_FALSE (!f->head_chunk))
522 end_chunk = f_chunk_end (f->head_chunk);
524 return f_pos_lt (end_chunk, tail) ? end_chunk - head : tail - head;
528 svm_fifo_max_write_chunk (svm_fifo_t * f)
532 f_load_head_tail_prod (f, &head, &tail);
533 ASSERT (!f->tail_chunk || f_chunk_includes_pos (f->tail_chunk, tail));
535 return f->tail_chunk ? f_chunk_end (f->tail_chunk) - tail : 0;
539 f_find_node_rbtree (rb_tree_t * rt, u32 pos)
541 rb_node_t *cur, *prev;
543 cur = rb_node (rt, rt->root);
544 if (PREDICT_FALSE (rb_node_is_tnil (rt, cur)))
547 while (pos != cur->key)
550 if (f_pos_lt (pos, cur->key))
552 cur = rb_node_left (rt, cur);
553 if (rb_node_is_tnil (rt, cur))
555 cur = rb_tree_predecessor (rt, prev);
561 cur = rb_node_right (rt, cur);
562 if (rb_node_is_tnil (rt, cur))
570 if (rb_node_is_tnil (rt, cur))
576 static svm_fifo_chunk_t *
577 f_find_chunk_rbtree (rb_tree_t * rt, u32 pos)
582 if (!rb_tree_is_init (rt))
585 n = f_find_node_rbtree (rt, pos);
588 c = uword_to_pointer (n->opaque, svm_fifo_chunk_t *);
589 if (f_chunk_includes_pos (c, pos))
596 f_update_ooo_enq (svm_fifo_t * f, u32 start_pos, u32 end_pos)
598 rb_tree_t *rt = &f->ooo_enq_lookup;
602 /* Use linear search if rbtree is not initialized */
603 if (PREDICT_FALSE (!rb_tree_is_init (rt)))
605 f->ooo_enq = svm_fifo_find_next_chunk (f, f->tail_chunk, start_pos);
609 if (rt->root == RBTREE_TNIL_INDEX)
612 ASSERT (c->enq_rb_index == RBTREE_TNIL_INDEX);
613 c->enq_rb_index = rb_tree_add_custom (rt, c->start_byte,
614 pointer_to_uword (c), f_pos_lt);
618 cur = f_find_node_rbtree (rt, start_pos);
619 c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
620 ASSERT (f_pos_leq (c->start_byte, start_pos));
623 if (f_chunk_includes_pos (c, start_pos))
626 if (f_chunk_includes_pos (c, end_pos))
632 if (!c || c->enq_rb_index != RBTREE_TNIL_INDEX)
635 c->enq_rb_index = rb_tree_add_custom (rt, c->start_byte,
636 pointer_to_uword (c), f_pos_lt);
638 if (f_chunk_includes_pos (c, start_pos))
641 while (!f_chunk_includes_pos (c, end_pos));
645 f_update_ooo_deq (svm_fifo_t * f, u32 start_pos, u32 end_pos)
647 rb_tree_t *rt = &f->ooo_deq_lookup;
651 /* Use linear search if rbtree is not initialized */
652 if (PREDICT_FALSE (!rb_tree_is_init (rt)))
654 f->ooo_deq = svm_fifo_find_chunk (f, start_pos);
658 if (rt->root == RBTREE_TNIL_INDEX)
661 ASSERT (c->deq_rb_index == RBTREE_TNIL_INDEX);
662 c->deq_rb_index = rb_tree_add_custom (rt, c->start_byte,
663 pointer_to_uword (c), f_pos_lt);
667 cur = f_find_node_rbtree (rt, start_pos);
668 c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
669 ASSERT (f_pos_leq (c->start_byte, start_pos));
672 if (f_chunk_includes_pos (c, start_pos))
675 if (f_chunk_includes_pos (c, end_pos))
681 if (!c || c->deq_rb_index != RBTREE_TNIL_INDEX)
684 c->deq_rb_index = rb_tree_add_custom (rt, c->start_byte,
685 pointer_to_uword (c), f_pos_lt);
687 if (f_chunk_includes_pos (c, start_pos))
690 while (!f_chunk_includes_pos (c, end_pos));
693 static svm_fifo_chunk_t *
694 f_lookup_clear_enq_chunks (svm_fifo_t * f, svm_fifo_chunk_t * start,
697 rb_tree_t *rt = &f->ooo_enq_lookup;
702 while (c && !f_chunk_includes_pos (c, end_pos))
704 if (c->enq_rb_index != RBTREE_TNIL_INDEX)
706 n = rb_node (rt, c->enq_rb_index);
707 rb_tree_del_node (rt, n);
708 c->enq_rb_index = RBTREE_TNIL_INDEX;
714 /* No ooo segments left, so make sure the current chunk
715 * is not tracked in the enq rbtree */
716 if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX
717 && c && c->enq_rb_index != RBTREE_TNIL_INDEX)
719 n = rb_node (rt, c->enq_rb_index);
720 rb_tree_del_node (rt, n);
721 c->enq_rb_index = RBTREE_TNIL_INDEX;
727 static svm_fifo_chunk_t *
728 f_lookup_clear_deq_chunks (svm_fifo_t * f, svm_fifo_chunk_t * start,
731 rb_tree_t *rt = &f->ooo_deq_lookup;
736 while (c && !f_chunk_includes_pos (c, end_pos))
738 if (c->deq_rb_index != RBTREE_TNIL_INDEX)
740 n = rb_node (rt, c->deq_rb_index);
741 rb_tree_del_node (rt, n);
742 c->deq_rb_index = RBTREE_TNIL_INDEX;
752 svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c)
754 svm_fifo_chunk_t *cur, *prev;
761 cur->start_byte = prev->start_byte + prev->length;
762 cur->enq_rb_index = RBTREE_TNIL_INDEX;
763 cur->deq_rb_index = RBTREE_TNIL_INDEX;
770 f->end_chunk->next = c;
780 svm_fifo_free_chunk_lookup (svm_fifo_t * f)
782 rb_tree_free_nodes (&f->ooo_enq_lookup);
783 rb_tree_free_nodes (&f->ooo_deq_lookup);
787 svm_fifo_free (svm_fifo_t * f)
789 ASSERT (f->refcnt > 0);
791 if (--f->refcnt == 0)
793 /* ooo data is not allocated on segment heap */
794 svm_fifo_free_chunk_lookup (f);
800 svm_fifo_overwrite_head (svm_fifo_t * f, u8 * src, u32 len)
803 u32 head, tail, head_idx;
806 ASSERT (len <= f->size);
808 f_load_head_tail_cons (f, &head, &tail);
811 f->head_chunk = svm_fifo_find_chunk (f, head);
814 head_idx = head - c->start_byte;
815 n_chunk = c->length - head_idx;
817 clib_memcpy_fast (&c->data[head_idx], src, len);
820 ASSERT (len - n_chunk <= c->next->length);
821 clib_memcpy_fast (&c->data[head_idx], src, n_chunk);
822 clib_memcpy_fast (&c->next->data[0], src + n_chunk, len - n_chunk);
827 f_try_grow (svm_fifo_t * f, u32 head, u32 tail, u32 len)
830 u32 alloc_size, free_alloced;
832 free_alloced = f_chunk_end (f->end_chunk) - tail;
833 ASSERT (free_alloced < len);
835 alloc_size = clib_min (f->min_alloc, f->size - (tail - head));
836 alloc_size = clib_max (alloc_size, len - free_alloced);
838 c = fsh_alloc_chunk (f->fs_hdr, f->slice_index, alloc_size);
839 if (PREDICT_FALSE (!c))
842 svm_fifo_add_chunk (f, c);
847 svm_fifo_enqueue (svm_fifo_t * f, u32 len, const u8 * src)
849 u32 tail, head, free_count;
850 svm_fifo_chunk_t *old_tail_c;
852 f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
854 f_load_head_tail_prod (f, &head, &tail);
856 /* free space in fifo can only increase during enqueue: SPSC */
857 free_count = f_free_count (f, head, tail);
859 if (PREDICT_FALSE (free_count == 0))
860 return SVM_FIFO_EFULL;
862 /* number of bytes we're going to copy */
863 len = clib_min (free_count, len);
865 if (f_pos_gt (tail + len, f_chunk_end (f->end_chunk)))
867 if (PREDICT_FALSE (f_try_grow (f, head, tail, len)))
869 len = f_chunk_end (f->end_chunk) - tail;
871 return SVM_FIFO_EGROW;
875 old_tail_c = f->tail_chunk;
877 svm_fifo_copy_to_chunk (f, f->tail_chunk, tail, src, len, &f->tail_chunk);
880 svm_fifo_trace_add (f, head, len, 2);
882 /* collect out-of-order segments */
883 if (PREDICT_FALSE (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX))
885 len += ooo_segment_try_collect (f, len, &tail);
886 /* Tail chunk might've changed even if nothing was collected */
887 f->tail_chunk = f_lookup_clear_enq_chunks (f, old_tail_c, tail);
891 /* store-rel: producer owned index (paired with load-acq in consumer) */
892 clib_atomic_store_rel_n (&f->tail, tail);
898 * Enqueue a future segment.
900 * Two choices: either copies the entire segment, or copies nothing
901 * Returns 0 of the entire segment was copied
902 * Returns -1 if none of the segment was copied due to lack of space
905 svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len, u8 * src)
907 u32 tail, head, free_count, enq_pos;
909 f_load_head_tail_prod (f, &head, &tail);
911 /* free space in fifo can only increase during enqueue: SPSC */
912 free_count = f_free_count (f, head, tail);
913 f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
915 /* will this request fit? */
916 if ((len + offset) > free_count)
917 return SVM_FIFO_EFULL;
919 enq_pos = tail + offset;
921 if (f_pos_gt (enq_pos + len, f_chunk_end (f->end_chunk)))
923 if (PREDICT_FALSE (f_try_grow (f, head, tail, offset + len)))
924 return SVM_FIFO_EGROW;
927 svm_fifo_trace_add (f, offset, len, 1);
928 ooo_segment_add (f, offset, head, tail, len);
930 if (!f->ooo_enq || !f_chunk_includes_pos (f->ooo_enq, enq_pos))
931 f_update_ooo_enq (f, enq_pos, enq_pos + len);
933 svm_fifo_copy_to_chunk (f, f->ooo_enq, enq_pos, src, len, &f->ooo_enq);
942 svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len)
946 ASSERT (len <= svm_fifo_max_enqueue_prod (f));
947 /* load-relaxed: producer owned index */
951 if (rb_tree_is_init (&f->ooo_enq_lookup))
953 f->tail_chunk = f_lookup_clear_enq_chunks (f, f->tail_chunk, tail);
958 f->tail_chunk = svm_fifo_find_next_chunk (f, f->tail_chunk, tail);
961 /* store-rel: producer owned index (paired with load-acq in consumer) */
962 clib_atomic_store_rel_n (&f->tail, tail);
965 always_inline svm_fifo_chunk_t *
966 f_unlink_chunks (svm_fifo_t * f, u32 end_pos, u8 maybe_ooo)
968 svm_fifo_chunk_t *start, *prev = 0, *c;
972 ASSERT (!f_chunk_includes_pos (f->start_chunk, end_pos));
975 rt = &f->ooo_deq_lookup;
981 if (maybe_ooo && c->deq_rb_index != RBTREE_TNIL_INDEX)
983 n = rb_node (rt, c->deq_rb_index);
984 ASSERT (n == f_find_node_rbtree (rt, c->start_byte));
985 rb_tree_del_node (rt, n);
986 c->deq_rb_index = RBTREE_TNIL_INDEX;
993 while (!f_chunk_includes_pos (c, end_pos));
997 if (f->ooo_deq && f_pos_lt (f->ooo_deq->start_byte, f_chunk_end (c)))
1002 if (PREDICT_FALSE (f->ooo_deq != 0))
1006 /* Avoid unlinking the last chunk */
1011 start = f->start_chunk;
1018 svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst)
1020 u32 tail, head, cursize;
1022 f_load_head_tail_cons (f, &head, &tail);
1024 /* current size of fifo can only increase during dequeue: SPSC */
1025 cursize = f_cursize (f, head, tail);
1027 if (PREDICT_FALSE (cursize == 0))
1028 return SVM_FIFO_EEMPTY;
1030 len = clib_min (cursize, len);
1033 f->head_chunk = svm_fifo_find_chunk (f, head);
1035 svm_fifo_copy_from_chunk (f, f->head_chunk, head, dst, len, &f->head_chunk);
1038 if (f_pos_geq (head, f_chunk_end (f->start_chunk)))
1039 fsh_collect_chunks (f->fs_hdr, f->slice_index,
1040 f_unlink_chunks (f, head, 0));
1042 /* store-rel: consumer owned index (paired with load-acq in producer) */
1043 clib_atomic_store_rel_n (&f->head, head);
1049 svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 len, u8 * dst)
1051 u32 tail, head, cursize, head_idx;
1053 f_load_head_tail_cons (f, &head, &tail);
1055 /* current size of fifo can only increase during peek: SPSC */
1056 cursize = f_cursize (f, head, tail);
1058 if (PREDICT_FALSE (cursize < offset))
1059 return SVM_FIFO_EEMPTY;
1061 len = clib_min (cursize - offset, len);
1062 head_idx = head + offset;
1064 if (!f->ooo_deq || !f_chunk_includes_pos (f->ooo_deq, head_idx))
1065 f_update_ooo_deq (f, head_idx, head_idx + len);
1067 svm_fifo_copy_from_chunk (f, f->ooo_deq, head_idx, dst, len, &f->ooo_deq);
1072 svm_fifo_dequeue_drop (svm_fifo_t * f, u32 len)
1074 u32 total_drop_bytes, tail, head, cursize;
1076 f_load_head_tail_cons (f, &head, &tail);
1078 /* number of bytes available */
1079 cursize = f_cursize (f, head, tail);
1080 if (PREDICT_FALSE (cursize == 0))
1081 return SVM_FIFO_EEMPTY;
1083 /* number of bytes we're going to drop */
1084 total_drop_bytes = clib_min (cursize, len);
1086 svm_fifo_trace_add (f, tail, total_drop_bytes, 3);
1089 head = head + total_drop_bytes;
1091 if (f_pos_geq (head, f_chunk_end (f->start_chunk)))
1093 fsh_collect_chunks (f->fs_hdr, f->slice_index,
1094 f_unlink_chunks (f, head, 1));
1096 f_chunk_includes_pos (f->start_chunk, head) ? f->start_chunk : 0;
1099 /* store-rel: consumer owned index (paired with load-acq in producer) */
1100 clib_atomic_store_rel_n (&f->head, head);
1102 return total_drop_bytes;
1106 * Drop all data from fifo
1108 * Should be called only from vpp side because of lookup cleanup
1111 svm_fifo_dequeue_drop_all (svm_fifo_t * f)
1115 f_load_head_tail_all_acq (f, &head, &tail);
1117 if (!f->head_chunk || !f_chunk_includes_pos (f->head_chunk, head))
1118 f->head_chunk = svm_fifo_find_chunk (f, head);
1120 f->head_chunk = f_lookup_clear_deq_chunks (f, f->head_chunk, tail);
1122 if (f_pos_geq (tail, f_chunk_end (f->start_chunk)))
1123 fsh_collect_chunks (f->fs_hdr, f->slice_index,
1124 f_unlink_chunks (f, tail, 0));
1126 /* store-rel: consumer owned index (paired with load-acq in producer) */
1127 clib_atomic_store_rel_n (&f->head, tail);
1131 svm_fifo_fill_chunk_list (svm_fifo_t * f)
1135 f_load_head_tail_prod (f, &head, &tail);
1137 if (f_chunk_end (f->end_chunk) - head >= f->size)
1140 if (f_try_grow (f, head, tail, f->size - (tail - head)))
1141 return SVM_FIFO_EGROW;
1147 svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs)
1149 u32 cursize, head, tail, head_idx;
1151 f_load_head_tail_cons (f, &head, &tail);
1153 /* consumer function, cursize can only increase while we're working */
1154 cursize = f_cursize (f, head, tail);
1156 if (PREDICT_FALSE (cursize == 0))
1157 return SVM_FIFO_EEMPTY;
1163 fs[0].len = f->size - head_idx;
1164 fs[0].data = f->head_chunk->data + head_idx;
1165 fs[1].len = cursize - fs[0].len;
1166 fs[1].data = f->head_chunk->data;
1170 fs[0].len = cursize;
1171 fs[0].data = f->head_chunk->data + head_idx;
1179 svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_seg_t * fs)
1183 /* consumer owned index */
1186 ASSERT (fs[0].data == f->head_chunk->data + head);
1187 head = (head + fs[0].len + fs[1].len);
1188 /* store-rel: consumer owned index (paired with load-acq in producer) */
1189 clib_atomic_store_rel_n (&f->head, head);
1196 * - no prod and cons are accessing either dest or src fifo
1197 * - fifo is not multi chunk
1200 svm_fifo_clone (svm_fifo_t * df, svm_fifo_t * sf)
1204 /* Support only single chunk clones for now */
1205 ASSERT (svm_fifo_n_chunks (sf) == 1);
1207 clib_memcpy_fast (df->head_chunk->data, sf->head_chunk->data, sf->size);
1209 f_load_head_tail_all_acq (sf, &head, &tail);
1210 clib_atomic_store_rel_n (&df->head, head);
1211 clib_atomic_store_rel_n (&df->tail, tail);
1215 svm_fifo_n_ooo_segments (svm_fifo_t * f)
1217 return pool_elts (f->ooo_segments);
1221 svm_fifo_first_ooo_segment (svm_fifo_t * f)
1223 return pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
1227 * Set fifo pointers to requested offset
1230 svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail)
1232 svm_fifo_chunk_t *c;
1234 clib_atomic_store_rel_n (&f->head, head);
1235 clib_atomic_store_rel_n (&f->tail, tail);
1237 c = svm_fifo_find_chunk (f, head);
1239 f->head_chunk = f->ooo_deq = c;
1240 c = svm_fifo_find_chunk (f, tail);
1242 f->tail_chunk = f->ooo_enq = c;
1246 svm_fifo_add_subscriber (svm_fifo_t * f, u8 subscriber)
1248 if (f->n_subscribers >= SVM_FIFO_MAX_EVT_SUBSCRIBERS)
1250 f->subscribers[f->n_subscribers++] = subscriber;
1254 svm_fifo_del_subscriber (svm_fifo_t * f, u8 subscriber)
1258 for (i = 0; i < f->n_subscribers; i++)
1260 if (f->subscribers[i] != subscriber)
1262 f->subscribers[i] = f->subscribers[f->n_subscribers - 1];
1269 svm_fifo_is_sane (svm_fifo_t * f)
1271 svm_fifo_chunk_t *tmp;
1273 if (f->head_chunk && !f_chunk_includes_pos (f->head_chunk, f->head))
1275 if (f->tail_chunk && !f_chunk_includes_pos (f->tail_chunk, f->tail))
1279 if (rb_tree_is_init (&f->ooo_deq_lookup))
1281 if (f_pos_lt (f->ooo_deq->start_byte, f->start_chunk->start_byte)
1282 || f_pos_gt (f->ooo_deq->start_byte,
1283 f_chunk_end (f->end_chunk)))
1286 tmp = f_find_chunk_rbtree (&f->ooo_deq_lookup,
1287 f->ooo_deq->start_byte);
1290 tmp = svm_fifo_find_chunk (f, f->ooo_deq->start_byte);
1291 if (tmp != f->ooo_deq)
1296 if (rb_tree_is_init (&f->ooo_enq_lookup))
1298 if (f_pos_lt (f->ooo_enq->start_byte, f->start_chunk->start_byte)
1299 || f_pos_gt (f->ooo_enq->start_byte,
1300 f_chunk_end (f->end_chunk)))
1303 tmp = f_find_chunk_rbtree (&f->ooo_enq_lookup,
1304 f->ooo_enq->start_byte);
1308 tmp = svm_fifo_find_next_chunk (f, f->tail_chunk,
1309 f->ooo_enq->start_byte);
1311 if (tmp != f->ooo_enq)
1315 if (f->start_chunk->next)
1317 svm_fifo_chunk_t *c, *prev = 0, *tmp;
1318 u32 chunks_bytes = 0;
1323 tmp = svm_fifo_find_chunk (f, c->start_byte);
1326 if (prev && (prev->start_byte + prev->length != c->start_byte))
1329 if (c->enq_rb_index != RBTREE_TNIL_INDEX)
1331 tmp = f_find_chunk_rbtree (&f->ooo_enq_lookup, c->start_byte);
1338 if (c->deq_rb_index != RBTREE_TNIL_INDEX)
1340 tmp = f_find_chunk_rbtree (&f->ooo_deq_lookup, c->start_byte);
1348 chunks_bytes += c->length;
1354 if (chunks_bytes < f->tail - f->head)
1362 svm_fifo_n_chunks (svm_fifo_t * f)
1364 svm_fifo_chunk_t *c;
1378 format_ooo_segment (u8 * s, va_list * args)
1380 svm_fifo_t __clib_unused *f = va_arg (*args, svm_fifo_t *);
1381 ooo_segment_t *seg = va_arg (*args, ooo_segment_t *);
1382 s = format (s, "[%u, %u], len %u, next %d, prev %d", seg->start,
1383 seg->start + seg->length, seg->length, seg->next, seg->prev);
1388 svm_fifo_dump_trace (u8 * s, svm_fifo_t * f)
1391 svm_fifo_trace_elem_t *seg = 0;
1396 vec_foreach (seg, f->trace)
1398 s = format (s, "{%u, %u, %u}, ", seg->offset, seg->len, seg->action);
1401 s = format (s, "\n");
1403 s = format (s, "\n");
1412 svm_fifo_replay (u8 * s, svm_fifo_t * f, u8 no_read, u8 verbose)
1416 svm_fifo_trace_elem_t *trace;
1418 svm_fifo_t *dummy_fifo;
1425 trace_len = vec_len (trace);
1431 dummy_fifo = svm_fifo_alloc (f->size);
1432 svm_fifo_init (f, f->size);
1433 clib_memset (f->head_chunk->data, 0xFF, f->size);
1434 vec_validate (data, f->size);
1435 for (i = 0; i < vec_len (data); i++)
1438 for (i = 0; i < trace_len; i++)
1440 offset = trace[i].offset;
1441 if (trace[i].action == 1)
1444 s = format (s, "adding [%u, %u]:", trace[i].offset,
1445 (trace[i].offset + trace[i].len));
1446 svm_fifo_enqueue_with_offset (dummy_fifo, trace[i].offset,
1447 trace[i].len, &data[offset]);
1449 else if (trace[i].action == 2)
1452 s = format (s, "adding [%u, %u]:", 0, trace[i].len);
1453 svm_fifo_enqueue (dummy_fifo, trace[i].len, &data[offset]);
1458 s = format (s, "read: %u", trace[i].len);
1459 svm_fifo_dequeue_drop (dummy_fifo, trace[i].len);
1462 s = format (s, "%U", format_svm_fifo, dummy_fifo, 1);
1465 s = format (s, "result: %U", format_svm_fifo, dummy_fifo, 1);
1471 format_ooo_list (u8 * s, va_list * args)
1473 svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
1474 u32 indent = va_arg (*args, u32);
1475 u32 ooo_segment_index = f->ooos_list_head;
1478 while (ooo_segment_index != OOO_SEGMENT_INVALID_INDEX)
1480 seg = pool_elt_at_index (f->ooo_segments, ooo_segment_index);
1481 s = format (s, "%U%U\n", format_white_space, indent, format_ooo_segment,
1483 ooo_segment_index = seg->next;
1490 format_svm_fifo (u8 * s, va_list * args)
1492 svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
1493 int verbose = va_arg (*args, int);
1499 indent = format_get_indent (s);
1500 s = format (s, "cursize %u nitems %u has_event %d min_alloc %u\n",
1501 svm_fifo_max_dequeue (f), f->size, f->has_event, f->min_alloc);
1502 s = format (s, "%Uhead %u tail %u segment manager %u\n", format_white_space,
1503 indent, f->head, f->tail, f->segment_manager);
1506 s = format (s, "%Uvpp session %d thread %d app session %d thread %d\n",
1507 format_white_space, indent, f->master_session_index,
1508 f->master_thread_index, f->client_session_index,
1509 f->client_thread_index);
1513 s = format (s, "%Uooo pool %d active elts newest %u\n",
1514 format_white_space, indent, pool_elts (f->ooo_segments),
1516 if (svm_fifo_has_ooo_data (f))
1517 s = format (s, " %U", format_ooo_list, f, indent, verbose);
1524 * fd.io coding-style-patch-verification: ON
1527 * eval: (c-set-style "gnu")