1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
10 #include <sys/queue.h>
12 #include <rte_memory.h>
14 #include <rte_launch.h>
15 #include <rte_per_lcore.h>
16 #include <rte_lcore.h>
17 #include <rte_debug.h>
18 #include <rte_common.h>
19 #include <rte_spinlock.h>
21 #include "eal_internal_cfg.h"
22 #include "eal_memalloc.h"
23 #include "malloc_elem.h"
24 #include "malloc_heap.h"
27 malloc_elem_find_max_iova_contig(struct malloc_elem *elem, size_t align)
29 void *cur_page, *contig_seg_start, *page_end, *cur_seg_end;
30 void *data_start, *data_end;
31 rte_iova_t expected_iova;
32 struct rte_memseg *ms;
33 size_t page_sz, cur, max;
35 page_sz = (size_t)elem->msl->page_sz;
36 data_start = RTE_PTR_ADD(elem, MALLOC_ELEM_HEADER_LEN);
37 data_end = RTE_PTR_ADD(elem, elem->size - MALLOC_ELEM_TRAILER_LEN);
38 /* segment must start after header and with specified alignment */
39 contig_seg_start = RTE_PTR_ALIGN_CEIL(data_start, align);
41 /* return if aligned address is already out of malloc element */
42 if (contig_seg_start > data_end)
45 /* if we're in IOVA as VA mode, or if we're in legacy mode with
46 * hugepages, all elements are IOVA-contiguous. however, we can only
47 * make these assumptions about internal memory - externally allocated
48 * segments have to be checked.
50 if (!elem->msl->external &&
51 (rte_eal_iova_mode() == RTE_IOVA_VA ||
52 (internal_config.legacy_mem &&
53 rte_eal_has_hugepages())))
54 return RTE_PTR_DIFF(data_end, contig_seg_start);
56 cur_page = RTE_PTR_ALIGN_FLOOR(contig_seg_start, page_sz);
57 ms = rte_mem_virt2memseg(cur_page, elem->msl);
59 /* do first iteration outside the loop */
60 page_end = RTE_PTR_ADD(cur_page, page_sz);
61 cur_seg_end = RTE_MIN(page_end, data_end);
62 cur = RTE_PTR_DIFF(cur_seg_end, contig_seg_start) -
63 MALLOC_ELEM_TRAILER_LEN;
65 expected_iova = ms->iova + page_sz;
66 /* memsegs are contiguous in memory */
69 cur_page = RTE_PTR_ADD(cur_page, page_sz);
71 while (cur_page < data_end) {
72 page_end = RTE_PTR_ADD(cur_page, page_sz);
73 cur_seg_end = RTE_MIN(page_end, data_end);
75 /* reset start of contiguous segment if unexpected iova */
76 if (ms->iova != expected_iova) {
77 /* next contiguous segment must start at specified
80 contig_seg_start = RTE_PTR_ALIGN(cur_page, align);
81 /* new segment start may be on a different page, so find
82 * the page and skip to next iteration to make sure
83 * we're not blowing past data end.
85 ms = rte_mem_virt2memseg(contig_seg_start, elem->msl);
87 /* don't trigger another recalculation */
88 expected_iova = ms->iova;
91 /* cur_seg_end ends on a page boundary or on data end. if we're
92 * looking at data end, then malloc trailer is already included
93 * in the calculations. if we're looking at page end, then we
94 * know there's more data past this page and thus there's space
95 * for malloc element trailer, so don't count it here.
97 cur = RTE_PTR_DIFF(cur_seg_end, contig_seg_start);
98 /* update max if cur value is bigger */
102 /* move to next page */
104 expected_iova = ms->iova + page_sz;
105 /* memsegs are contiguous in memory */
113 * Initialize a general malloc_elem header structure
116 malloc_elem_init(struct malloc_elem *elem, struct malloc_heap *heap,
117 struct rte_memseg_list *msl, size_t size,
118 struct malloc_elem *orig_elem, size_t orig_size)
124 memset(&elem->free_list, 0, sizeof(elem->free_list));
125 elem->state = ELEM_FREE;
128 elem->orig_elem = orig_elem;
129 elem->orig_size = orig_size;
135 malloc_elem_insert(struct malloc_elem *elem)
137 struct malloc_elem *prev_elem, *next_elem;
138 struct malloc_heap *heap = elem->heap;
140 /* first and last elements must be both NULL or both non-NULL */
141 if ((heap->first == NULL) != (heap->last == NULL)) {
142 RTE_LOG(ERR, EAL, "Heap is probably corrupt\n");
146 if (heap->first == NULL && heap->last == NULL) {
152 } else if (elem < heap->first) {
153 /* if lower than start */
155 next_elem = heap->first;
157 } else if (elem > heap->last) {
158 /* if higher than end */
159 prev_elem = heap->last;
163 /* the new memory is somewhere inbetween start and end */
164 uint64_t dist_from_start, dist_from_end;
166 dist_from_end = RTE_PTR_DIFF(heap->last, elem);
167 dist_from_start = RTE_PTR_DIFF(elem, heap->first);
169 /* check which is closer, and find closest list entries */
170 if (dist_from_start < dist_from_end) {
171 prev_elem = heap->first;
172 while (prev_elem->next < elem)
173 prev_elem = prev_elem->next;
174 next_elem = prev_elem->next;
176 next_elem = heap->last;
177 while (next_elem->prev > elem)
178 next_elem = next_elem->prev;
179 prev_elem = next_elem->prev;
183 /* insert new element */
184 elem->prev = prev_elem;
185 elem->next = next_elem;
187 prev_elem->next = elem;
189 next_elem->prev = elem;
193 * Attempt to find enough physically contiguous memory in this block to store
194 * our data. Assume that element has at least enough space to fit in the data,
195 * so we just check the page addresses.
198 elem_check_phys_contig(const struct rte_memseg_list *msl,
199 void *start, size_t size)
201 return eal_memalloc_is_contig(msl, start, size);
205 * calculate the starting point of where data of the requested size
206 * and alignment would fit in the current element. If the data doesn't
210 elem_start_pt(struct malloc_elem *elem, size_t size, unsigned align,
211 size_t bound, bool contig)
213 size_t elem_size = elem->size;
216 * we're allocating from the end, so adjust the size of element by
219 while (elem_size >= size) {
220 const size_t bmask = ~(bound - 1);
221 uintptr_t end_pt = (uintptr_t)elem +
222 elem_size - MALLOC_ELEM_TRAILER_LEN;
223 uintptr_t new_data_start = RTE_ALIGN_FLOOR((end_pt - size),
225 uintptr_t new_elem_start;
228 if ((new_data_start & bmask) != ((end_pt - 1) & bmask)) {
229 end_pt = RTE_ALIGN_FLOOR(end_pt, bound);
230 new_data_start = RTE_ALIGN_FLOOR((end_pt - size),
232 end_pt = new_data_start + size;
234 if (((end_pt - 1) & bmask) != (new_data_start & bmask))
238 new_elem_start = new_data_start - MALLOC_ELEM_HEADER_LEN;
240 /* if the new start point is before the exist start,
243 if (new_elem_start < (uintptr_t)elem)
247 size_t new_data_size = end_pt - new_data_start;
250 * if physical contiguousness was requested and we
251 * couldn't fit all data into one physically contiguous
252 * block, try again with lower addresses.
254 if (!elem_check_phys_contig(elem->msl,
255 (void *)new_data_start,
261 return (void *)new_elem_start;
267 * use elem_start_pt to determine if we get meet the size and
268 * alignment request from the current element
271 malloc_elem_can_hold(struct malloc_elem *elem, size_t size, unsigned align,
272 size_t bound, bool contig)
274 return elem_start_pt(elem, size, align, bound, contig) != NULL;
278 * split an existing element into two smaller elements at the given
279 * split_pt parameter.
282 split_elem(struct malloc_elem *elem, struct malloc_elem *split_pt)
284 struct malloc_elem *next_elem = elem->next;
285 const size_t old_elem_size = (uintptr_t)split_pt - (uintptr_t)elem;
286 const size_t new_elem_size = elem->size - old_elem_size;
288 malloc_elem_init(split_pt, elem->heap, elem->msl, new_elem_size,
289 elem->orig_elem, elem->orig_size);
290 split_pt->prev = elem;
291 split_pt->next = next_elem;
293 next_elem->prev = split_pt;
295 elem->heap->last = split_pt;
296 elem->next = split_pt;
297 elem->size = old_elem_size;
302 * our malloc heap is a doubly linked list, so doubly remove our element.
304 static void __rte_unused
305 remove_elem(struct malloc_elem *elem)
307 struct malloc_elem *next, *prev;
314 elem->heap->last = prev;
318 elem->heap->first = next;
325 next_elem_is_adjacent(struct malloc_elem *elem)
327 return elem->next == RTE_PTR_ADD(elem, elem->size) &&
328 elem->next->msl == elem->msl &&
329 (!internal_config.match_allocations ||
330 elem->orig_elem == elem->next->orig_elem);
334 prev_elem_is_adjacent(struct malloc_elem *elem)
336 return elem == RTE_PTR_ADD(elem->prev, elem->prev->size) &&
337 elem->prev->msl == elem->msl &&
338 (!internal_config.match_allocations ||
339 elem->orig_elem == elem->prev->orig_elem);
343 * Given an element size, compute its freelist index.
344 * We free an element into the freelist containing similarly-sized elements.
345 * We try to allocate elements starting with the freelist containing
346 * similarly-sized elements, and if necessary, we search freelists
347 * containing larger elements.
349 * Example element size ranges for a heap with five free lists:
350 * heap->free_head[0] - (0 , 2^8]
351 * heap->free_head[1] - (2^8 , 2^10]
352 * heap->free_head[2] - (2^10 ,2^12]
353 * heap->free_head[3] - (2^12, 2^14]
354 * heap->free_head[4] - (2^14, MAX_SIZE]
357 malloc_elem_free_list_index(size_t size)
359 #define MALLOC_MINSIZE_LOG2 8
360 #define MALLOC_LOG2_INCREMENT 2
365 if (size <= (1UL << MALLOC_MINSIZE_LOG2))
368 /* Find next power of 2 >= size. */
369 log2 = sizeof(size) * 8 - __builtin_clzl(size-1);
371 /* Compute freelist index, based on log2(size). */
372 index = (log2 - MALLOC_MINSIZE_LOG2 + MALLOC_LOG2_INCREMENT - 1) /
373 MALLOC_LOG2_INCREMENT;
375 return index <= RTE_HEAP_NUM_FREELISTS-1?
376 index: RTE_HEAP_NUM_FREELISTS-1;
380 * Add the specified element to its heap's free list.
383 malloc_elem_free_list_insert(struct malloc_elem *elem)
387 idx = malloc_elem_free_list_index(elem->size - MALLOC_ELEM_HEADER_LEN);
388 elem->state = ELEM_FREE;
389 LIST_INSERT_HEAD(&elem->heap->free_head[idx], elem, free_list);
393 * Remove the specified element from its heap's free list.
396 malloc_elem_free_list_remove(struct malloc_elem *elem)
398 LIST_REMOVE(elem, free_list);
402 * reserve a block of data in an existing malloc_elem. If the malloc_elem
403 * is much larger than the data block requested, we split the element in two.
404 * This function is only called from malloc_heap_alloc so parameter checking
405 * is not done here, as it's done there previously.
408 malloc_elem_alloc(struct malloc_elem *elem, size_t size, unsigned align,
409 size_t bound, bool contig)
411 struct malloc_elem *new_elem = elem_start_pt(elem, size, align, bound,
413 const size_t old_elem_size = (uintptr_t)new_elem - (uintptr_t)elem;
414 const size_t trailer_size = elem->size - old_elem_size - size -
415 MALLOC_ELEM_OVERHEAD;
417 malloc_elem_free_list_remove(elem);
419 if (trailer_size > MALLOC_ELEM_OVERHEAD + MIN_DATA_SIZE) {
420 /* split it, too much free space after elem */
421 struct malloc_elem *new_free_elem =
422 RTE_PTR_ADD(new_elem, size + MALLOC_ELEM_OVERHEAD);
424 split_elem(elem, new_free_elem);
425 malloc_elem_free_list_insert(new_free_elem);
427 if (elem == elem->heap->last)
428 elem->heap->last = new_free_elem;
431 if (old_elem_size < MALLOC_ELEM_OVERHEAD + MIN_DATA_SIZE) {
432 /* don't split it, pad the element instead */
433 elem->state = ELEM_BUSY;
434 elem->pad = old_elem_size;
436 /* put a dummy header in padding, to point to real element header */
437 if (elem->pad > 0) { /* pad will be at least 64-bytes, as everything
438 * is cache-line aligned */
439 new_elem->pad = elem->pad;
440 new_elem->state = ELEM_PAD;
441 new_elem->size = elem->size - elem->pad;
442 set_header(new_elem);
448 /* we are going to split the element in two. The original element
449 * remains free, and the new element is the one allocated.
450 * Re-insert original element, in case its new size makes it
451 * belong on a different list.
453 split_elem(elem, new_elem);
454 new_elem->state = ELEM_BUSY;
455 malloc_elem_free_list_insert(elem);
461 * join two struct malloc_elem together. elem1 and elem2 must
462 * be contiguous in memory.
465 join_elem(struct malloc_elem *elem1, struct malloc_elem *elem2)
467 struct malloc_elem *next = elem2->next;
468 elem1->size += elem2->size;
472 elem1->heap->last = elem1;
477 malloc_elem_join_adjacent_free(struct malloc_elem *elem)
480 * check if next element exists, is adjacent and is free, if so join
481 * with it, need to remove from free list.
483 if (elem->next != NULL && elem->next->state == ELEM_FREE &&
484 next_elem_is_adjacent(elem)) {
488 /* we will want to erase the trailer and header */
489 erase = RTE_PTR_SUB(elem->next, MALLOC_ELEM_TRAILER_LEN);
490 erase_len = MALLOC_ELEM_OVERHEAD + elem->next->pad;
492 /* remove from free list, join to this one */
493 malloc_elem_free_list_remove(elem->next);
494 join_elem(elem, elem->next);
496 /* erase header, trailer and pad */
497 memset(erase, 0, erase_len);
501 * check if prev element exists, is adjacent and is free, if so join
502 * with it, need to remove from free list.
504 if (elem->prev != NULL && elem->prev->state == ELEM_FREE &&
505 prev_elem_is_adjacent(elem)) {
506 struct malloc_elem *new_elem;
510 /* we will want to erase trailer and header */
511 erase = RTE_PTR_SUB(elem, MALLOC_ELEM_TRAILER_LEN);
512 erase_len = MALLOC_ELEM_OVERHEAD + elem->pad;
514 /* remove from free list, join to this one */
515 malloc_elem_free_list_remove(elem->prev);
517 new_elem = elem->prev;
518 join_elem(new_elem, elem);
520 /* erase header, trailer and pad */
521 memset(erase, 0, erase_len);
530 * free a malloc_elem block by adding it to the free list. If the
531 * blocks either immediately before or immediately after newly freed block
532 * are also free, the blocks are merged together.
535 malloc_elem_free(struct malloc_elem *elem)
540 ptr = RTE_PTR_ADD(elem, MALLOC_ELEM_HEADER_LEN);
541 data_len = elem->size - MALLOC_ELEM_OVERHEAD;
543 elem = malloc_elem_join_adjacent_free(elem);
545 malloc_elem_free_list_insert(elem);
549 /* decrease heap's count of allocated elements */
550 elem->heap->alloc_count--;
552 memset(ptr, 0, data_len);
557 /* assume all checks were already done */
559 malloc_elem_hide_region(struct malloc_elem *elem, void *start, size_t len)
561 struct malloc_elem *hide_start, *hide_end, *prev, *next;
562 size_t len_before, len_after;
565 hide_end = RTE_PTR_ADD(start, len);
570 /* we cannot do anything with non-adjacent elements */
571 if (next && next_elem_is_adjacent(elem)) {
572 len_after = RTE_PTR_DIFF(next, hide_end);
573 if (len_after >= MALLOC_ELEM_OVERHEAD + MIN_DATA_SIZE) {
575 split_elem(elem, hide_end);
577 malloc_elem_free_list_insert(hide_end);
578 } else if (len_after > 0) {
579 RTE_LOG(ERR, EAL, "Unaligned element, heap is probably corrupt\n");
584 /* we cannot do anything with non-adjacent elements */
585 if (prev && prev_elem_is_adjacent(elem)) {
586 len_before = RTE_PTR_DIFF(hide_start, elem);
587 if (len_before >= MALLOC_ELEM_OVERHEAD + MIN_DATA_SIZE) {
589 split_elem(elem, hide_start);
594 malloc_elem_free_list_insert(prev);
595 } else if (len_before > 0) {
596 RTE_LOG(ERR, EAL, "Unaligned element, heap is probably corrupt\n");
605 * attempt to resize a malloc_elem by expanding into any free space
606 * immediately after it in memory.
609 malloc_elem_resize(struct malloc_elem *elem, size_t size)
611 const size_t new_size = size + elem->pad + MALLOC_ELEM_OVERHEAD;
613 /* if we request a smaller size, then always return ok */
614 if (elem->size >= new_size)
617 /* check if there is a next element, it's free and adjacent */
618 if (!elem->next || elem->next->state != ELEM_FREE ||
619 !next_elem_is_adjacent(elem))
621 if (elem->size + elem->next->size < new_size)
624 /* we now know the element fits, so remove from free list,
627 malloc_elem_free_list_remove(elem->next);
628 join_elem(elem, elem->next);
630 if (elem->size - new_size >= MIN_DATA_SIZE + MALLOC_ELEM_OVERHEAD) {
631 /* now we have a big block together. Lets cut it down a bit, by splitting */
632 struct malloc_elem *split_pt = RTE_PTR_ADD(elem, new_size);
633 split_pt = RTE_PTR_ALIGN_CEIL(split_pt, RTE_CACHE_LINE_SIZE);
634 split_elem(elem, split_pt);
635 malloc_elem_free_list_insert(split_pt);
640 static inline const char *
641 elem_state_to_str(enum elem_state state)
655 malloc_elem_dump(const struct malloc_elem *elem, FILE *f)
657 fprintf(f, "Malloc element at %p (%s)\n", elem,
658 elem_state_to_str(elem->state));
659 fprintf(f, " len: 0x%zx pad: 0x%" PRIx32 "\n", elem->size, elem->pad);
660 fprintf(f, " prev: %p next: %p\n", elem->prev, elem->next);