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 CLIB_MEM_UNPOISON (c, sizeof (*c));
74 CLIB_MEM_UNPOISON (c->data, c->length);
75 n_chunk = clib_min (c->length, to_copy);
76 clib_memcpy_fast (dst + (len - to_copy), &c->data[0], n_chunk);
77 c = c->length <= to_copy ? c->next : c;
84 clib_memcpy_fast (dst, &c->data[head_idx], len);
88 #ifndef CLIB_MARCH_VARIANT
91 svm_fifo_copy_to_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c, u32 tail_idx,
92 const u8 * src, u32 len, svm_fifo_chunk_t ** last)
94 CLIB_MARCH_FN_SELECT (svm_fifo_copy_to_chunk) (f, c, tail_idx, src, len,
99 svm_fifo_copy_from_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c, u32 head_idx,
100 u8 * dst, u32 len, svm_fifo_chunk_t ** last)
102 CLIB_MARCH_FN_SELECT (svm_fifo_copy_from_chunk) (f, c, head_idx, dst, len,
107 ooo_segment_end_pos (ooo_segment_t * s)
109 return (s->start + s->length);
113 svm_fifo_free_ooo_data (svm_fifo_t * f)
115 pool_free (f->ooo_segments);
118 static inline ooo_segment_t *
119 ooo_segment_prev (svm_fifo_t * f, ooo_segment_t * s)
121 if (s->prev == OOO_SEGMENT_INVALID_INDEX)
123 return pool_elt_at_index (f->ooo_segments, s->prev);
126 static inline ooo_segment_t *
127 ooo_segment_next (svm_fifo_t * f, ooo_segment_t * s)
129 if (s->next == OOO_SEGMENT_INVALID_INDEX)
131 return pool_elt_at_index (f->ooo_segments, s->next);
134 static inline ooo_segment_t *
135 ooo_segment_alloc (svm_fifo_t * f, u32 start, u32 length)
139 pool_get (f->ooo_segments, s);
143 s->prev = s->next = OOO_SEGMENT_INVALID_INDEX;
149 ooo_segment_free (svm_fifo_t * f, u32 index)
151 ooo_segment_t *cur, *prev = 0, *next = 0;
152 cur = pool_elt_at_index (f->ooo_segments, index);
154 if (cur->next != OOO_SEGMENT_INVALID_INDEX)
156 next = pool_elt_at_index (f->ooo_segments, cur->next);
157 next->prev = cur->prev;
160 if (cur->prev != OOO_SEGMENT_INVALID_INDEX)
162 prev = pool_elt_at_index (f->ooo_segments, cur->prev);
163 prev->next = cur->next;
167 f->ooos_list_head = cur->next;
170 pool_put (f->ooo_segments, cur);
174 * Add segment to fifo's out-of-order segment list. Takes care of merging
175 * adjacent segments and removing overlapping ones.
178 ooo_segment_add (svm_fifo_t * f, u32 offset, u32 head, u32 tail, u32 length)
180 ooo_segment_t *s, *new_s, *prev, *next, *it;
181 u32 new_index, s_end_pos, s_index;
182 u32 offset_pos, offset_end_pos;
184 ASSERT (offset + length <= f_free_count (f, head, tail));
186 offset_pos = tail + offset;
187 offset_end_pos = tail + offset + length;
189 f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
191 if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
193 s = ooo_segment_alloc (f, offset_pos, length);
194 f->ooos_list_head = s - f->ooo_segments;
195 f->ooos_newest = f->ooos_list_head;
199 /* Find first segment that starts after new segment */
200 s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
201 while (s->next != OOO_SEGMENT_INVALID_INDEX
202 && f_pos_lt (s->start, offset_pos))
203 s = pool_elt_at_index (f->ooo_segments, s->next);
205 /* If we have a previous and we overlap it, use it as starting point */
206 prev = ooo_segment_prev (f, s);
207 if (prev && f_pos_leq (offset_pos, ooo_segment_end_pos (prev)))
210 s_end_pos = ooo_segment_end_pos (s);
212 /* Since we have previous, offset start position cannot be smaller
213 * than prev->start. Check tail */
214 ASSERT (f_pos_lt (s->start, offset_pos));
218 s_index = s - f->ooo_segments;
219 s_end_pos = ooo_segment_end_pos (s);
221 /* No overlap, add before current segment */
222 if (f_pos_lt (offset_end_pos, s->start))
224 new_s = ooo_segment_alloc (f, offset_pos, length);
225 new_index = new_s - f->ooo_segments;
227 /* Pool might've moved, get segment again */
228 s = pool_elt_at_index (f->ooo_segments, s_index);
229 if (s->prev != OOO_SEGMENT_INVALID_INDEX)
231 new_s->prev = s->prev;
232 prev = pool_elt_at_index (f->ooo_segments, new_s->prev);
233 prev->next = new_index;
238 f->ooos_list_head = new_index;
241 new_s->next = s_index;
243 f->ooos_newest = new_index;
246 /* No overlap, add after current segment */
247 else if (f_pos_gt (offset_pos, s_end_pos))
249 new_s = ooo_segment_alloc (f, offset_pos, length);
250 new_index = new_s - f->ooo_segments;
252 /* Pool might've moved, get segment again */
253 s = pool_elt_at_index (f->ooo_segments, s_index);
255 /* Needs to be last */
256 ASSERT (s->next == OOO_SEGMENT_INVALID_INDEX);
258 new_s->prev = s_index;
260 f->ooos_newest = new_index;
270 if (f_pos_lt (offset_pos, s->start))
272 s->start = offset_pos;
273 s->length = s_end_pos - s->start;
274 f->ooos_newest = s - f->ooo_segments;
279 /* Overlapping tail */
280 if (f_pos_gt (offset_end_pos, s_end_pos))
282 s->length = offset_end_pos - s->start;
284 /* Remove the completely overlapped segments in the tail */
285 it = ooo_segment_next (f, s);
286 while (it && f_pos_leq (ooo_segment_end_pos (it), offset_end_pos))
288 next = ooo_segment_next (f, it);
289 ooo_segment_free (f, it - f->ooo_segments);
293 /* If partial overlap with last, merge */
294 if (it && f_pos_leq (it->start, offset_end_pos))
296 s->length = ooo_segment_end_pos (it) - s->start;
297 ooo_segment_free (f, it - f->ooo_segments);
299 f->ooos_newest = s - f->ooo_segments;
304 * Removes segments that can now be enqueued because the fifo's tail has
305 * advanced. Returns the number of bytes added to tail.
308 ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail)
310 u32 s_index, bytes = 0;
314 s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
315 diff = *tail - s->start;
317 ASSERT (diff != n_bytes_enqueued);
319 if (diff > n_bytes_enqueued)
322 /* If last tail update overlaps one/multiple ooo segments, remove them */
323 while (0 <= diff && diff < n_bytes_enqueued)
325 s_index = s - f->ooo_segments;
327 /* Segment end is beyond the tail. Advance tail and remove segment */
328 if (s->length > diff)
330 bytes = s->length - diff;
331 *tail = *tail + bytes;
332 ooo_segment_free (f, s_index);
336 /* If we have next go on */
337 if (s->next != OOO_SEGMENT_INVALID_INDEX)
339 s = pool_elt_at_index (f->ooo_segments, s->next);
340 diff = *tail - s->start;
341 ooo_segment_free (f, s_index);
346 ooo_segment_free (f, s_index);
351 ASSERT (bytes <= f->size);
355 __clib_unused static ooo_segment_t *
356 ooo_segment_last (svm_fifo_t * f)
360 if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
363 s = svm_fifo_first_ooo_segment (f);
364 while (s->next != OOO_SEGMENT_INVALID_INDEX)
365 s = pool_elt_at_index (f->ooo_segments, s->next);
370 svm_fifo_init (svm_fifo_t * f, u32 size)
372 svm_fifo_chunk_t *c, *prev;
376 f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
377 f->segment_index = SVM_FIFO_INVALID_INDEX;
379 f->head = f->tail = f->flags = 0;
380 f->head_chunk = f->tail_chunk = f->start_chunk;
381 f->ooo_deq = f->ooo_enq = 0;
383 min_alloc = size > 32 << 10 ? size >> 3 : 4096;
384 min_alloc = clib_min (min_alloc, 64 << 10);
385 f->min_alloc = min_alloc;
390 f->start_chunk->start_byte = 0;
391 prev = f->start_chunk;
396 c->start_byte = prev->start_byte + prev->length;
403 svm_fifo_init_ooo_lookup (svm_fifo_t * f, u8 ooo_type)
407 ASSERT (!rb_tree_is_init (&f->ooo_enq_lookup));
408 rb_tree_init (&f->ooo_enq_lookup);
412 ASSERT (!rb_tree_is_init (&f->ooo_deq_lookup));
413 rb_tree_init (&f->ooo_deq_lookup);
418 * Creates a fifo in the current heap. Fails vs blow up the process
421 svm_fifo_alloc (u32 data_size_in_bytes)
423 u32 rounded_data_size;
427 f = clib_mem_alloc_aligned_or_null (sizeof (*f), CLIB_CACHE_LINE_BYTES);
431 clib_memset (f, 0, sizeof (*f));
433 /* always round fifo data size to the next highest power-of-two */
434 rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
435 c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_data_size,
436 CLIB_CACHE_LINE_BYTES);
443 clib_memset (c, 0, sizeof (*c));
445 c->length = data_size_in_bytes;
446 c->enq_rb_index = RBTREE_TNIL_INDEX;
447 c->deq_rb_index = RBTREE_TNIL_INDEX;
448 f->start_chunk = f->end_chunk = c;
454 * Creates a fifo chunk in the current heap
457 svm_fifo_chunk_alloc (u32 size)
462 /* round chunk size to the next highest power-of-two */
463 rounded_size = (1 << (max_log2 (size)));
464 c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_size,
465 CLIB_CACHE_LINE_BYTES);
469 clib_memset (c, 0, sizeof (*c));
470 c->length = rounded_size;
475 * Find chunk for given byte position
478 * @param pos normalized position in fifo
480 * @return chunk that includes given position or 0
482 static svm_fifo_chunk_t *
483 svm_fifo_find_chunk (svm_fifo_t * f, u32 pos)
488 while (c && !f_chunk_includes_pos (c, pos))
494 static svm_fifo_chunk_t *
495 svm_fifo_find_next_chunk (svm_fifo_t * f, svm_fifo_chunk_t * start, u32 pos)
502 while (c && !f_chunk_includes_pos (c, pos))
509 svm_fifo_max_read_chunk (svm_fifo_t * f)
511 u32 head, tail, end_chunk;
513 f_load_head_tail_cons (f, &head, &tail);
514 ASSERT (!f->head_chunk || f_chunk_includes_pos (f->head_chunk, head));
518 f->head_chunk = svm_fifo_find_chunk (f, head);
519 if (PREDICT_FALSE (!f->head_chunk))
523 end_chunk = f_chunk_end (f->head_chunk);
525 return f_pos_lt (end_chunk, tail) ? end_chunk - head : tail - head;
529 svm_fifo_max_write_chunk (svm_fifo_t * f)
533 f_load_head_tail_prod (f, &head, &tail);
534 ASSERT (!f->tail_chunk || f_chunk_includes_pos (f->tail_chunk, tail));
536 return f->tail_chunk ? f_chunk_end (f->tail_chunk) - tail : 0;
540 f_find_node_rbtree (rb_tree_t * rt, u32 pos)
542 rb_node_t *cur, *prev;
544 cur = rb_node (rt, rt->root);
545 if (PREDICT_FALSE (rb_node_is_tnil (rt, cur)))
548 while (pos != cur->key)
551 if (f_pos_lt (pos, cur->key))
553 cur = rb_node_left (rt, cur);
554 if (rb_node_is_tnil (rt, cur))
556 cur = rb_tree_predecessor (rt, prev);
562 cur = rb_node_right (rt, cur);
563 if (rb_node_is_tnil (rt, cur))
571 if (rb_node_is_tnil (rt, cur))
577 static svm_fifo_chunk_t *
578 f_find_chunk_rbtree (rb_tree_t * rt, u32 pos)
583 if (!rb_tree_is_init (rt))
586 n = f_find_node_rbtree (rt, pos);
589 c = uword_to_pointer (n->opaque, svm_fifo_chunk_t *);
590 if (f_chunk_includes_pos (c, pos))
597 f_update_ooo_enq (svm_fifo_t * f, u32 start_pos, u32 end_pos)
599 rb_tree_t *rt = &f->ooo_enq_lookup;
603 /* Use linear search if rbtree is not initialized */
604 if (PREDICT_FALSE (!rb_tree_is_init (rt)))
606 f->ooo_enq = svm_fifo_find_next_chunk (f, f->tail_chunk, start_pos);
610 if (rt->root == RBTREE_TNIL_INDEX)
613 ASSERT (c->enq_rb_index == RBTREE_TNIL_INDEX);
614 c->enq_rb_index = rb_tree_add_custom (rt, c->start_byte,
615 pointer_to_uword (c), f_pos_lt);
619 cur = f_find_node_rbtree (rt, start_pos);
620 c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
621 ASSERT (f_pos_leq (c->start_byte, start_pos));
624 if (f_chunk_includes_pos (c, start_pos))
627 if (f_chunk_includes_pos (c, end_pos))
633 if (!c || c->enq_rb_index != RBTREE_TNIL_INDEX)
636 c->enq_rb_index = rb_tree_add_custom (rt, c->start_byte,
637 pointer_to_uword (c), f_pos_lt);
639 if (f_chunk_includes_pos (c, start_pos))
642 while (!f_chunk_includes_pos (c, end_pos));
646 f_update_ooo_deq (svm_fifo_t * f, u32 start_pos, u32 end_pos)
648 rb_tree_t *rt = &f->ooo_deq_lookup;
652 /* Use linear search if rbtree is not initialized */
653 if (PREDICT_FALSE (!rb_tree_is_init (rt)))
655 f->ooo_deq = svm_fifo_find_chunk (f, start_pos);
659 if (rt->root == RBTREE_TNIL_INDEX)
662 ASSERT (c->deq_rb_index == RBTREE_TNIL_INDEX);
663 c->deq_rb_index = rb_tree_add_custom (rt, c->start_byte,
664 pointer_to_uword (c), f_pos_lt);
668 cur = f_find_node_rbtree (rt, start_pos);
669 c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
670 ASSERT (f_pos_leq (c->start_byte, start_pos));
673 if (f_chunk_includes_pos (c, start_pos))
676 if (f_chunk_includes_pos (c, end_pos))
682 if (!c || c->deq_rb_index != RBTREE_TNIL_INDEX)
685 c->deq_rb_index = rb_tree_add_custom (rt, c->start_byte,
686 pointer_to_uword (c), f_pos_lt);
688 if (f_chunk_includes_pos (c, start_pos))
691 while (!f_chunk_includes_pos (c, end_pos));
694 static svm_fifo_chunk_t *
695 f_lookup_clear_enq_chunks (svm_fifo_t * f, svm_fifo_chunk_t * start,
698 rb_tree_t *rt = &f->ooo_enq_lookup;
703 while (c && !f_chunk_includes_pos (c, end_pos))
705 if (c->enq_rb_index != RBTREE_TNIL_INDEX)
707 n = rb_node (rt, c->enq_rb_index);
708 rb_tree_del_node (rt, n);
709 c->enq_rb_index = RBTREE_TNIL_INDEX;
715 /* No ooo segments left, so make sure the current chunk
716 * is not tracked in the enq rbtree */
717 if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX
718 && c && c->enq_rb_index != RBTREE_TNIL_INDEX)
720 n = rb_node (rt, c->enq_rb_index);
721 rb_tree_del_node (rt, n);
722 c->enq_rb_index = RBTREE_TNIL_INDEX;
728 static svm_fifo_chunk_t *
729 f_lookup_clear_deq_chunks (svm_fifo_t * f, svm_fifo_chunk_t * start,
732 rb_tree_t *rt = &f->ooo_deq_lookup;
737 while (c && !f_chunk_includes_pos (c, end_pos))
739 if (c->deq_rb_index != RBTREE_TNIL_INDEX)
741 n = rb_node (rt, c->deq_rb_index);
742 rb_tree_del_node (rt, n);
743 c->deq_rb_index = RBTREE_TNIL_INDEX;
753 svm_fifo_free_chunk_lookup (svm_fifo_t * f)
755 rb_tree_free_nodes (&f->ooo_enq_lookup);
756 rb_tree_free_nodes (&f->ooo_deq_lookup);
760 svm_fifo_free (svm_fifo_t * f)
762 ASSERT (f->refcnt > 0);
764 if (--f->refcnt == 0)
766 /* ooo data is not allocated on segment heap */
767 svm_fifo_free_chunk_lookup (f);
773 svm_fifo_overwrite_head (svm_fifo_t * f, u8 * src, u32 len)
776 u32 head, tail, head_idx;
779 ASSERT (len <= f->size);
781 f_load_head_tail_cons (f, &head, &tail);
784 f->head_chunk = svm_fifo_find_chunk (f, head);
787 head_idx = head - c->start_byte;
788 n_chunk = c->length - head_idx;
790 clib_memcpy_fast (&c->data[head_idx], src, len);
793 ASSERT (len - n_chunk <= c->next->length);
794 clib_memcpy_fast (&c->data[head_idx], src, n_chunk);
795 clib_memcpy_fast (&c->next->data[0], src + n_chunk, len - n_chunk);
800 f_try_chunk_alloc (svm_fifo_t * f, u32 head, u32 tail, u32 len)
802 svm_fifo_chunk_t *c, *cur, *prev;
803 u32 alloc_size, free_alloced;
805 free_alloced = f_chunk_end (f->end_chunk) - tail;
807 alloc_size = clib_min (f->min_alloc, f->size - (tail - head));
808 alloc_size = clib_max (alloc_size, len - free_alloced);
810 c = fsh_alloc_chunk (f->fs_hdr, f->slice_index, alloc_size);
811 if (PREDICT_FALSE (!c))
819 cur->start_byte = prev->start_byte + prev->length;
820 cur->enq_rb_index = RBTREE_TNIL_INDEX;
821 cur->deq_rb_index = RBTREE_TNIL_INDEX;
828 f->end_chunk->next = c;
838 svm_fifo_enqueue (svm_fifo_t * f, u32 len, const u8 * src)
840 u32 tail, head, free_count;
841 svm_fifo_chunk_t *old_tail_c;
843 f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
845 f_load_head_tail_prod (f, &head, &tail);
847 /* free space in fifo can only increase during enqueue: SPSC */
848 free_count = f_free_count (f, head, tail);
850 if (PREDICT_FALSE (free_count == 0))
851 return SVM_FIFO_EFULL;
853 /* number of bytes we're going to copy */
854 len = clib_min (free_count, len);
856 if (f_pos_gt (tail + len, f_chunk_end (f->end_chunk)))
858 if (PREDICT_FALSE (f_try_chunk_alloc (f, head, tail, len)))
860 len = f_chunk_end (f->end_chunk) - tail;
862 return SVM_FIFO_EGROW;
866 old_tail_c = f->tail_chunk;
868 svm_fifo_copy_to_chunk (f, f->tail_chunk, tail, src, len, &f->tail_chunk);
871 svm_fifo_trace_add (f, head, len, 2);
873 /* collect out-of-order segments */
874 if (PREDICT_FALSE (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX))
876 len += ooo_segment_try_collect (f, len, &tail);
877 /* Tail chunk might've changed even if nothing was collected */
878 f->tail_chunk = f_lookup_clear_enq_chunks (f, old_tail_c, tail);
882 /* store-rel: producer owned index (paired with load-acq in consumer) */
883 clib_atomic_store_rel_n (&f->tail, tail);
889 * Enqueue a future segment.
891 * Two choices: either copies the entire segment, or copies nothing
892 * Returns 0 of the entire segment was copied
893 * Returns -1 if none of the segment was copied due to lack of space
896 svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len, u8 * src)
898 u32 tail, head, free_count, enq_pos;
900 f_load_head_tail_prod (f, &head, &tail);
902 /* free space in fifo can only increase during enqueue: SPSC */
903 free_count = f_free_count (f, head, tail);
904 f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
906 /* will this request fit? */
907 if ((len + offset) > free_count)
908 return SVM_FIFO_EFULL;
910 enq_pos = tail + offset;
912 if (f_pos_gt (enq_pos + len, f_chunk_end (f->end_chunk)))
914 if (PREDICT_FALSE (f_try_chunk_alloc (f, head, tail, offset + len)))
915 return SVM_FIFO_EGROW;
918 svm_fifo_trace_add (f, offset, len, 1);
919 ooo_segment_add (f, offset, head, tail, len);
921 if (!f->ooo_enq || !f_chunk_includes_pos (f->ooo_enq, enq_pos))
922 f_update_ooo_enq (f, enq_pos, enq_pos + len);
924 svm_fifo_copy_to_chunk (f, f->ooo_enq, enq_pos, src, len, &f->ooo_enq);
933 svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len)
937 ASSERT (len <= svm_fifo_max_enqueue_prod (f));
938 /* load-relaxed: producer owned index */
942 if (rb_tree_is_init (&f->ooo_enq_lookup))
944 f->tail_chunk = f_lookup_clear_enq_chunks (f, f->tail_chunk, tail);
949 f->tail_chunk = svm_fifo_find_next_chunk (f, f->tail_chunk, tail);
952 /* store-rel: producer owned index (paired with load-acq in consumer) */
953 clib_atomic_store_rel_n (&f->tail, tail);
956 always_inline svm_fifo_chunk_t *
957 f_unlink_chunks (svm_fifo_t * f, u32 end_pos, u8 maybe_ooo)
959 svm_fifo_chunk_t *start, *prev = 0, *c;
963 ASSERT (!f_chunk_includes_pos (f->start_chunk, end_pos));
966 rt = &f->ooo_deq_lookup;
972 if (maybe_ooo && c->deq_rb_index != RBTREE_TNIL_INDEX)
974 n = rb_node (rt, c->deq_rb_index);
975 ASSERT (n == f_find_node_rbtree (rt, c->start_byte));
976 rb_tree_del_node (rt, n);
977 c->deq_rb_index = RBTREE_TNIL_INDEX;
984 while (!f_chunk_includes_pos (c, end_pos));
988 if (f->ooo_deq && f_pos_lt (f->ooo_deq->start_byte, f_chunk_end (c)))
993 if (PREDICT_FALSE (f->ooo_deq != 0))
997 /* Avoid unlinking the last chunk */
1002 start = f->start_chunk;
1009 svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst)
1011 u32 tail, head, cursize;
1013 f_load_head_tail_cons (f, &head, &tail);
1015 /* current size of fifo can only increase during dequeue: SPSC */
1016 cursize = f_cursize (f, head, tail);
1018 if (PREDICT_FALSE (cursize == 0))
1019 return SVM_FIFO_EEMPTY;
1021 len = clib_min (cursize, len);
1024 f->head_chunk = svm_fifo_find_chunk (f, head);
1026 svm_fifo_copy_from_chunk (f, f->head_chunk, head, dst, len, &f->head_chunk);
1029 /* In order dequeues are not supported in combination with ooo peeking.
1030 * Use svm_fifo_dequeue_drop instead. */
1031 ASSERT (rb_tree_n_nodes (&f->ooo_deq_lookup) <= 1);
1033 if (f_pos_geq (head, f_chunk_end (f->start_chunk)))
1034 fsh_collect_chunks (f->fs_hdr, f->slice_index,
1035 f_unlink_chunks (f, head, 0));
1037 /* store-rel: consumer owned index (paired with load-acq in producer) */
1038 clib_atomic_store_rel_n (&f->head, head);
1044 svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 len, u8 * dst)
1046 u32 tail, head, cursize, head_idx;
1048 f_load_head_tail_cons (f, &head, &tail);
1050 /* current size of fifo can only increase during peek: SPSC */
1051 cursize = f_cursize (f, head, tail);
1053 if (PREDICT_FALSE (cursize < offset))
1054 return SVM_FIFO_EEMPTY;
1056 len = clib_min (cursize - offset, len);
1057 head_idx = head + offset;
1059 CLIB_MEM_UNPOISON (f->ooo_deq, sizeof (*f->ooo_deq));
1060 if (!f->ooo_deq || !f_chunk_includes_pos (f->ooo_deq, head_idx))
1061 f_update_ooo_deq (f, head_idx, head_idx + len);
1063 svm_fifo_copy_from_chunk (f, f->ooo_deq, head_idx, dst, len, &f->ooo_deq);
1068 svm_fifo_dequeue_drop (svm_fifo_t * f, u32 len)
1070 u32 total_drop_bytes, tail, head, cursize;
1072 f_load_head_tail_cons (f, &head, &tail);
1074 /* number of bytes available */
1075 cursize = f_cursize (f, head, tail);
1076 if (PREDICT_FALSE (cursize == 0))
1077 return SVM_FIFO_EEMPTY;
1079 /* number of bytes we're going to drop */
1080 total_drop_bytes = clib_min (cursize, len);
1082 svm_fifo_trace_add (f, tail, total_drop_bytes, 3);
1085 head = head + total_drop_bytes;
1087 if (f_pos_geq (head, f_chunk_end (f->start_chunk)))
1089 fsh_collect_chunks (f->fs_hdr, f->slice_index,
1090 f_unlink_chunks (f, head, 1));
1092 f_chunk_includes_pos (f->start_chunk, head) ? f->start_chunk : 0;
1095 /* store-rel: consumer owned index (paired with load-acq in producer) */
1096 clib_atomic_store_rel_n (&f->head, head);
1098 return total_drop_bytes;
1102 * Drop all data from fifo
1106 svm_fifo_dequeue_drop_all (svm_fifo_t * f)
1110 f_load_head_tail_all_acq (f, &head, &tail);
1112 if (!f->head_chunk || !f_chunk_includes_pos (f->head_chunk, head))
1113 f->head_chunk = svm_fifo_find_chunk (f, head);
1115 f->head_chunk = f_lookup_clear_deq_chunks (f, f->head_chunk, tail);
1117 if (f_pos_geq (tail, f_chunk_end (f->start_chunk)))
1118 fsh_collect_chunks (f->fs_hdr, f->slice_index,
1119 f_unlink_chunks (f, tail, 0));
1121 /* store-rel: consumer owned index (paired with load-acq in producer) */
1122 clib_atomic_store_rel_n (&f->head, tail);
1126 svm_fifo_fill_chunk_list (svm_fifo_t * f)
1130 f_load_head_tail_prod (f, &head, &tail);
1132 if (f_chunk_end (f->end_chunk) - head >= f->size)
1135 if (f_try_chunk_alloc (f, head, tail, f->size - (tail - head)))
1136 return SVM_FIFO_EGROW;
1142 svm_fifo_segments (svm_fifo_t * f, u32 offset, svm_fifo_seg_t * fs,
1143 u32 n_segs, u32 max_bytes)
1145 u32 cursize, to_read, head, tail, fs_index = 1;
1146 u32 n_bytes, head_pos, len, start;
1147 svm_fifo_chunk_t *c;
1149 f_load_head_tail_cons (f, &head, &tail);
1151 /* consumer function, cursize can only increase while we're working */
1152 cursize = f_cursize (f, head, tail);
1154 if (PREDICT_FALSE (cursize == 0))
1155 return SVM_FIFO_EEMPTY;
1157 if (offset >= cursize)
1158 return SVM_FIFO_EEMPTY;
1160 to_read = clib_min (cursize - offset, max_bytes);
1161 start = head + offset;
1164 f->head_chunk = svm_fifo_find_chunk (f, head);
1168 while (!f_chunk_includes_pos (c, start))
1171 head_pos = start - c->start_byte;
1172 fs[0].data = c->data + head_pos;
1173 fs[0].len = clib_min (c->length - head_pos, cursize - offset);
1174 n_bytes = fs[0].len;
1176 while (n_bytes < to_read && fs_index < n_segs)
1179 len = clib_min (c->length, to_read - n_bytes);
1180 fs[fs_index].data = c->data;
1181 fs[fs_index].len = len;
1193 * - no prod and cons are accessing either dest or src fifo
1194 * - fifo is not multi chunk
1197 svm_fifo_clone (svm_fifo_t * df, svm_fifo_t * sf)
1201 /* Support only single chunk clones for now */
1202 ASSERT (svm_fifo_n_chunks (sf) == 1);
1204 clib_memcpy_fast (df->head_chunk->data, sf->head_chunk->data, sf->size);
1206 f_load_head_tail_all_acq (sf, &head, &tail);
1207 clib_atomic_store_rel_n (&df->head, head);
1208 clib_atomic_store_rel_n (&df->tail, tail);
1212 svm_fifo_n_ooo_segments (svm_fifo_t * f)
1214 return pool_elts (f->ooo_segments);
1218 svm_fifo_first_ooo_segment (svm_fifo_t * f)
1220 return pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
1224 * Set fifo pointers to requested offset
1227 svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail)
1229 svm_fifo_chunk_t *c;
1231 clib_atomic_store_rel_n (&f->head, head);
1232 clib_atomic_store_rel_n (&f->tail, tail);
1234 c = svm_fifo_find_chunk (f, head);
1236 f->head_chunk = f->ooo_deq = c;
1237 c = svm_fifo_find_chunk (f, tail);
1239 f->tail_chunk = f->ooo_enq = c;
1243 svm_fifo_add_subscriber (svm_fifo_t * f, u8 subscriber)
1245 if (f->n_subscribers >= SVM_FIFO_MAX_EVT_SUBSCRIBERS)
1247 f->subscribers[f->n_subscribers++] = subscriber;
1251 svm_fifo_del_subscriber (svm_fifo_t * f, u8 subscriber)
1255 for (i = 0; i < f->n_subscribers; i++)
1257 if (f->subscribers[i] != subscriber)
1259 f->subscribers[i] = f->subscribers[f->n_subscribers - 1];
1266 svm_fifo_is_sane (svm_fifo_t * f)
1268 svm_fifo_chunk_t *tmp;
1270 if (f->head_chunk && !f_chunk_includes_pos (f->head_chunk, f->head))
1272 if (f->tail_chunk && !f_chunk_includes_pos (f->tail_chunk, f->tail))
1276 if (rb_tree_is_init (&f->ooo_deq_lookup))
1278 if (f_pos_lt (f->ooo_deq->start_byte, f->start_chunk->start_byte)
1279 || f_pos_gt (f->ooo_deq->start_byte,
1280 f_chunk_end (f->end_chunk)))
1283 tmp = f_find_chunk_rbtree (&f->ooo_deq_lookup,
1284 f->ooo_deq->start_byte);
1287 tmp = svm_fifo_find_chunk (f, f->ooo_deq->start_byte);
1288 if (tmp != f->ooo_deq)
1293 if (rb_tree_is_init (&f->ooo_enq_lookup))
1295 if (f_pos_lt (f->ooo_enq->start_byte, f->start_chunk->start_byte)
1296 || f_pos_gt (f->ooo_enq->start_byte,
1297 f_chunk_end (f->end_chunk)))
1300 tmp = f_find_chunk_rbtree (&f->ooo_enq_lookup,
1301 f->ooo_enq->start_byte);
1305 tmp = svm_fifo_find_next_chunk (f, f->tail_chunk,
1306 f->ooo_enq->start_byte);
1308 if (tmp != f->ooo_enq)
1312 if (f->start_chunk->next)
1314 svm_fifo_chunk_t *c, *prev = 0, *tmp;
1315 u32 chunks_bytes = 0;
1320 tmp = svm_fifo_find_chunk (f, c->start_byte);
1323 if (prev && (prev->start_byte + prev->length != c->start_byte))
1326 if (c->enq_rb_index != RBTREE_TNIL_INDEX)
1328 tmp = f_find_chunk_rbtree (&f->ooo_enq_lookup, c->start_byte);
1335 if (c->deq_rb_index != RBTREE_TNIL_INDEX)
1337 tmp = f_find_chunk_rbtree (&f->ooo_deq_lookup, c->start_byte);
1345 chunks_bytes += c->length;
1351 if (chunks_bytes < f->tail - f->head)
1359 svm_fifo_n_chunks (svm_fifo_t * f)
1361 svm_fifo_chunk_t *c;
1375 format_ooo_segment (u8 * s, va_list * args)
1377 svm_fifo_t __clib_unused *f = va_arg (*args, svm_fifo_t *);
1378 ooo_segment_t *seg = va_arg (*args, ooo_segment_t *);
1379 s = format (s, "[%u, %u], len %u, next %d, prev %d", seg->start,
1380 seg->start + seg->length, seg->length, seg->next, seg->prev);
1385 svm_fifo_dump_trace (u8 * s, svm_fifo_t * f)
1388 svm_fifo_trace_elem_t *seg = 0;
1393 vec_foreach (seg, f->trace)
1395 s = format (s, "{%u, %u, %u}, ", seg->offset, seg->len, seg->action);
1398 s = format (s, "\n");
1400 s = format (s, "\n");
1409 svm_fifo_replay (u8 * s, svm_fifo_t * f, u8 no_read, u8 verbose)
1413 svm_fifo_trace_elem_t *trace;
1415 svm_fifo_t *placeholder_fifo;
1422 trace_len = vec_len (trace);
1428 placeholder_fifo = svm_fifo_alloc (f->size);
1429 svm_fifo_init (f, f->size);
1430 clib_memset (f->head_chunk->data, 0xFF, f->size);
1431 vec_validate (data, f->size);
1432 for (i = 0; i < vec_len (data); i++)
1435 for (i = 0; i < trace_len; i++)
1437 offset = trace[i].offset;
1438 if (trace[i].action == 1)
1441 s = format (s, "adding [%u, %u]:", trace[i].offset,
1442 (trace[i].offset + trace[i].len));
1443 svm_fifo_enqueue_with_offset (placeholder_fifo, trace[i].offset,
1444 trace[i].len, &data[offset]);
1446 else if (trace[i].action == 2)
1449 s = format (s, "adding [%u, %u]:", 0, trace[i].len);
1450 svm_fifo_enqueue (placeholder_fifo, trace[i].len, &data[offset]);
1455 s = format (s, "read: %u", trace[i].len);
1456 svm_fifo_dequeue_drop (placeholder_fifo, trace[i].len);
1459 s = format (s, "%U", format_svm_fifo, placeholder_fifo, 1);
1462 s = format (s, "result: %U", format_svm_fifo, placeholder_fifo, 1);
1468 format_ooo_list (u8 * s, va_list * args)
1470 svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
1471 u32 indent = va_arg (*args, u32);
1472 u32 ooo_segment_index = f->ooos_list_head;
1475 while (ooo_segment_index != OOO_SEGMENT_INVALID_INDEX)
1477 seg = pool_elt_at_index (f->ooo_segments, ooo_segment_index);
1478 s = format (s, "%U%U\n", format_white_space, indent, format_ooo_segment,
1480 ooo_segment_index = seg->next;
1487 format_svm_fifo (u8 * s, va_list * args)
1489 svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
1490 int verbose = va_arg (*args, int);
1496 indent = format_get_indent (s);
1497 s = format (s, "cursize %u nitems %u has_event %d min_alloc %u\n",
1498 svm_fifo_max_dequeue (f), f->size, f->has_event, f->min_alloc);
1499 s = format (s, "%Uhead %u tail %u segment manager %u\n", format_white_space,
1500 indent, f->head, f->tail, f->segment_manager);
1503 s = format (s, "%Uvpp session %d thread %d app session %d thread %d\n",
1504 format_white_space, indent, f->master_session_index,
1505 f->master_thread_index, f->client_session_index,
1506 f->client_thread_index);
1510 s = format (s, "%Uooo pool %d active elts newest %u\n",
1511 format_white_space, indent, pool_elts (f->ooo_segments),
1513 if (svm_fifo_has_ooo_data (f))
1514 s = format (s, " %U", format_ooo_list, f, indent, verbose);
1521 * fd.io coding-style-patch-verification: ON
1524 * eval: (c-set-style "gnu")