pack-objects: implement bitmap writing
[git/git.git] / pack-bitmap.c
CommitLineData
fff42755
VM
1#include "cache.h"
2#include "commit.h"
3#include "tag.h"
4#include "diff.h"
5#include "revision.h"
6#include "progress.h"
7#include "list-objects.h"
8#include "pack.h"
9#include "pack-bitmap.h"
10#include "pack-revindex.h"
11#include "pack-objects.h"
12
13/*
14 * An entry on the bitmap index, representing the bitmap for a given
15 * commit.
16 */
17struct stored_bitmap {
18 unsigned char sha1[20];
19 struct ewah_bitmap *root;
20 struct stored_bitmap *xor;
21 int flags;
22};
23
24/*
25 * The currently active bitmap index. By design, repositories only have
26 * a single bitmap index available (the index for the biggest packfile in
27 * the repository), since bitmap indexes need full closure.
28 *
29 * If there is more than one bitmap index available (e.g. because of alternates),
30 * the active bitmap index is the largest one.
31 */
32static struct bitmap_index {
33 /* Packfile to which this bitmap index belongs to */
34 struct packed_git *pack;
35
36 /* reverse index for the packfile */
37 struct pack_revindex *reverse_index;
38
39 /*
40 * Mark the first `reuse_objects` in the packfile as reused:
41 * they will be sent as-is without using them for repacking
42 * calculations
43 */
44 uint32_t reuse_objects;
45
46 /* mmapped buffer of the whole bitmap index */
47 unsigned char *map;
48 size_t map_size; /* size of the mmaped buffer */
49 size_t map_pos; /* current position when loading the index */
50
51 /*
52 * Type indexes.
53 *
54 * Each bitmap marks which objects in the packfile are of the given
55 * type. This provides type information when yielding the objects from
56 * the packfile during a walk, which allows for better delta bases.
57 */
58 struct ewah_bitmap *commits;
59 struct ewah_bitmap *trees;
60 struct ewah_bitmap *blobs;
61 struct ewah_bitmap *tags;
62
63 /* Map from SHA1 -> `stored_bitmap` for all the bitmapped comits */
64 khash_sha1 *bitmaps;
65
66 /* Number of bitmapped commits */
67 uint32_t entry_count;
68
69 /*
70 * Extended index.
71 *
72 * When trying to perform bitmap operations with objects that are not
73 * packed in `pack`, these objects are added to this "fake index" and
74 * are assumed to appear at the end of the packfile for all operations
75 */
76 struct eindex {
77 struct object **objects;
78 uint32_t *hashes;
79 uint32_t count, alloc;
80 khash_sha1_pos *positions;
81 } ext_index;
82
83 /* Bitmap result of the last performed walk */
84 struct bitmap *result;
85
86 /* Version of the bitmap index */
87 unsigned int version;
88
89 unsigned loaded : 1;
90
91} bitmap_git;
92
93static struct ewah_bitmap *lookup_stored_bitmap(struct stored_bitmap *st)
94{
95 struct ewah_bitmap *parent;
96 struct ewah_bitmap *composed;
97
98 if (st->xor == NULL)
99 return st->root;
100
101 composed = ewah_pool_new();
102 parent = lookup_stored_bitmap(st->xor);
103 ewah_xor(st->root, parent, composed);
104
105 ewah_pool_free(st->root);
106 st->root = composed;
107 st->xor = NULL;
108
109 return composed;
110}
111
112/*
113 * Read a bitmap from the current read position on the mmaped
114 * index, and increase the read position accordingly
115 */
116static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)
117{
118 struct ewah_bitmap *b = ewah_pool_new();
119
120 int bitmap_size = ewah_read_mmap(b,
121 index->map + index->map_pos,
122 index->map_size - index->map_pos);
123
124 if (bitmap_size < 0) {
125 error("Failed to load bitmap index (corrupted?)");
126 ewah_pool_free(b);
127 return NULL;
128 }
129
130 index->map_pos += bitmap_size;
131 return b;
132}
133
134static int load_bitmap_header(struct bitmap_index *index)
135{
136 struct bitmap_disk_header *header = (void *)index->map;
137
138 if (index->map_size < sizeof(*header) + 20)
139 return error("Corrupted bitmap index (missing header data)");
140
141 if (memcmp(header->magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE)) != 0)
142 return error("Corrupted bitmap index file (wrong header)");
143
144 index->version = ntohs(header->version);
145 if (index->version != 1)
146 return error("Unsupported version for bitmap index file (%d)", index->version);
147
148 /* Parse known bitmap format options */
149 {
150 uint32_t flags = ntohs(header->options);
151
152 if ((flags & BITMAP_OPT_FULL_DAG) == 0)
153 return error("Unsupported options for bitmap index file "
154 "(Git requires BITMAP_OPT_FULL_DAG)");
155 }
156
157 index->entry_count = ntohl(header->entry_count);
158 index->map_pos += sizeof(*header);
159 return 0;
160}
161
162static struct stored_bitmap *store_bitmap(struct bitmap_index *index,
163 struct ewah_bitmap *root,
164 const unsigned char *sha1,
165 struct stored_bitmap *xor_with,
166 int flags)
167{
168 struct stored_bitmap *stored;
169 khiter_t hash_pos;
170 int ret;
171
172 stored = xmalloc(sizeof(struct stored_bitmap));
173 stored->root = root;
174 stored->xor = xor_with;
175 stored->flags = flags;
176 hashcpy(stored->sha1, sha1);
177
178 hash_pos = kh_put_sha1(index->bitmaps, stored->sha1, &ret);
179
180 /* a 0 return code means the insertion succeeded with no changes,
181 * because the SHA1 already existed on the map. this is bad, there
182 * shouldn't be duplicated commits in the index */
183 if (ret == 0) {
184 error("Duplicate entry in bitmap index: %s", sha1_to_hex(sha1));
185 return NULL;
186 }
187
188 kh_value(index->bitmaps, hash_pos) = stored;
189 return stored;
190}
191
192static int load_bitmap_entries_v1(struct bitmap_index *index)
193{
194 static const size_t MAX_XOR_OFFSET = 160;
195
196 uint32_t i;
197 struct stored_bitmap **recent_bitmaps;
198 struct bitmap_disk_entry *entry;
199
200 recent_bitmaps = xcalloc(MAX_XOR_OFFSET, sizeof(struct stored_bitmap));
201
202 for (i = 0; i < index->entry_count; ++i) {
203 int xor_offset, flags;
204 struct ewah_bitmap *bitmap = NULL;
205 struct stored_bitmap *xor_bitmap = NULL;
206 uint32_t commit_idx_pos;
207 const unsigned char *sha1;
208
209 entry = (struct bitmap_disk_entry *)(index->map + index->map_pos);
210 index->map_pos += sizeof(struct bitmap_disk_entry);
211
212 commit_idx_pos = ntohl(entry->object_pos);
213 sha1 = nth_packed_object_sha1(index->pack, commit_idx_pos);
214
215 xor_offset = (int)entry->xor_offset;
216 flags = (int)entry->flags;
217
218 bitmap = read_bitmap_1(index);
219 if (!bitmap)
220 return -1;
221
222 if (xor_offset > MAX_XOR_OFFSET || xor_offset > i)
223 return error("Corrupted bitmap pack index");
224
225 if (xor_offset > 0) {
226 xor_bitmap = recent_bitmaps[(i - xor_offset) % MAX_XOR_OFFSET];
227
228 if (xor_bitmap == NULL)
229 return error("Invalid XOR offset in bitmap pack index");
230 }
231
232 recent_bitmaps[i % MAX_XOR_OFFSET] = store_bitmap(
233 index, bitmap, sha1, xor_bitmap, flags);
234 }
235
236 return 0;
237}
238
239static int open_pack_bitmap_1(struct packed_git *packfile)
240{
241 int fd;
242 struct stat st;
243 char *idx_name;
244
245 if (open_pack_index(packfile))
246 return -1;
247
248 idx_name = pack_bitmap_filename(packfile);
249 fd = git_open_noatime(idx_name);
250 free(idx_name);
251
252 if (fd < 0)
253 return -1;
254
255 if (fstat(fd, &st)) {
256 close(fd);
257 return -1;
258 }
259
260 if (bitmap_git.pack) {
261 warning("ignoring extra bitmap file: %s", packfile->pack_name);
262 close(fd);
263 return -1;
264 }
265
266 bitmap_git.pack = packfile;
267 bitmap_git.map_size = xsize_t(st.st_size);
268 bitmap_git.map = xmmap(NULL, bitmap_git.map_size, PROT_READ, MAP_PRIVATE, fd, 0);
269 bitmap_git.map_pos = 0;
270 close(fd);
271
272 if (load_bitmap_header(&bitmap_git) < 0) {
273 munmap(bitmap_git.map, bitmap_git.map_size);
274 bitmap_git.map = NULL;
275 bitmap_git.map_size = 0;
276 return -1;
277 }
278
279 return 0;
280}
281
282static int load_pack_bitmap(void)
283{
284 assert(bitmap_git.map && !bitmap_git.loaded);
285
286 bitmap_git.bitmaps = kh_init_sha1();
287 bitmap_git.ext_index.positions = kh_init_sha1_pos();
288 bitmap_git.reverse_index = revindex_for_pack(bitmap_git.pack);
289
290 if (!(bitmap_git.commits = read_bitmap_1(&bitmap_git)) ||
291 !(bitmap_git.trees = read_bitmap_1(&bitmap_git)) ||
292 !(bitmap_git.blobs = read_bitmap_1(&bitmap_git)) ||
293 !(bitmap_git.tags = read_bitmap_1(&bitmap_git)))
294 goto failed;
295
296 if (load_bitmap_entries_v1(&bitmap_git) < 0)
297 goto failed;
298
299 bitmap_git.loaded = 1;
300 return 0;
301
302failed:
303 munmap(bitmap_git.map, bitmap_git.map_size);
304 bitmap_git.map = NULL;
305 bitmap_git.map_size = 0;
306 return -1;
307}
308
309char *pack_bitmap_filename(struct packed_git *p)
310{
311 char *idx_name;
312 int len;
313
314 len = strlen(p->pack_name) - strlen(".pack");
315 idx_name = xmalloc(len + strlen(".bitmap") + 1);
316
317 memcpy(idx_name, p->pack_name, len);
318 memcpy(idx_name + len, ".bitmap", strlen(".bitmap") + 1);
319
320 return idx_name;
321}
322
323static int open_pack_bitmap(void)
324{
325 struct packed_git *p;
326 int ret = -1;
327
328 assert(!bitmap_git.map && !bitmap_git.loaded);
329
330 prepare_packed_git();
331 for (p = packed_git; p; p = p->next) {
332 if (open_pack_bitmap_1(p) == 0)
333 ret = 0;
334 }
335
336 return ret;
337}
338
339int prepare_bitmap_git(void)
340{
341 if (bitmap_git.loaded)
342 return 0;
343
344 if (!open_pack_bitmap())
345 return load_pack_bitmap();
346
347 return -1;
348}
349
350struct include_data {
351 struct bitmap *base;
352 struct bitmap *seen;
353};
354
355static inline int bitmap_position_extended(const unsigned char *sha1)
356{
357 khash_sha1_pos *positions = bitmap_git.ext_index.positions;
358 khiter_t pos = kh_get_sha1_pos(positions, sha1);
359
360 if (pos < kh_end(positions)) {
361 int bitmap_pos = kh_value(positions, pos);
362 return bitmap_pos + bitmap_git.pack->num_objects;
363 }
364
365 return -1;
366}
367
368static inline int bitmap_position_packfile(const unsigned char *sha1)
369{
370 off_t offset = find_pack_entry_one(sha1, bitmap_git.pack);
371 if (!offset)
372 return -1;
373
374 return find_revindex_position(bitmap_git.reverse_index, offset);
375}
376
377static int bitmap_position(const unsigned char *sha1)
378{
379 int pos = bitmap_position_packfile(sha1);
380 return (pos >= 0) ? pos : bitmap_position_extended(sha1);
381}
382
383static int ext_index_add_object(struct object *object, const char *name)
384{
385 struct eindex *eindex = &bitmap_git.ext_index;
386
387 khiter_t hash_pos;
388 int hash_ret;
389 int bitmap_pos;
390
391 hash_pos = kh_put_sha1_pos(eindex->positions, object->sha1, &hash_ret);
392 if (hash_ret > 0) {
393 if (eindex->count >= eindex->alloc) {
394 eindex->alloc = (eindex->alloc + 16) * 3 / 2;
395 eindex->objects = xrealloc(eindex->objects,
396 eindex->alloc * sizeof(struct object *));
397 eindex->hashes = xrealloc(eindex->hashes,
398 eindex->alloc * sizeof(uint32_t));
399 }
400
401 bitmap_pos = eindex->count;
402 eindex->objects[eindex->count] = object;
403 eindex->hashes[eindex->count] = pack_name_hash(name);
404 kh_value(eindex->positions, hash_pos) = bitmap_pos;
405 eindex->count++;
406 } else {
407 bitmap_pos = kh_value(eindex->positions, hash_pos);
408 }
409
410 return bitmap_pos + bitmap_git.pack->num_objects;
411}
412
413static void show_object(struct object *object, const struct name_path *path,
414 const char *last, void *data)
415{
416 struct bitmap *base = data;
417 int bitmap_pos;
418
419 bitmap_pos = bitmap_position(object->sha1);
420
421 if (bitmap_pos < 0) {
422 char *name = path_name(path, last);
423 bitmap_pos = ext_index_add_object(object, name);
424 free(name);
425 }
426
427 bitmap_set(base, bitmap_pos);
428}
429
430static void show_commit(struct commit *commit, void *data)
431{
432}
433
434static int add_to_include_set(struct include_data *data,
435 const unsigned char *sha1,
436 int bitmap_pos)
437{
438 khiter_t hash_pos;
439
440 if (data->seen && bitmap_get(data->seen, bitmap_pos))
441 return 0;
442
443 if (bitmap_get(data->base, bitmap_pos))
444 return 0;
445
446 hash_pos = kh_get_sha1(bitmap_git.bitmaps, sha1);
447 if (hash_pos < kh_end(bitmap_git.bitmaps)) {
448 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, hash_pos);
449 bitmap_or_ewah(data->base, lookup_stored_bitmap(st));
450 return 0;
451 }
452
453 bitmap_set(data->base, bitmap_pos);
454 return 1;
455}
456
457static int should_include(struct commit *commit, void *_data)
458{
459 struct include_data *data = _data;
460 int bitmap_pos;
461
462 bitmap_pos = bitmap_position(commit->object.sha1);
463 if (bitmap_pos < 0)
464 bitmap_pos = ext_index_add_object((struct object *)commit, NULL);
465
466 if (!add_to_include_set(data, commit->object.sha1, bitmap_pos)) {
467 struct commit_list *parent = commit->parents;
468
469 while (parent) {
470 parent->item->object.flags |= SEEN;
471 parent = parent->next;
472 }
473
474 return 0;
475 }
476
477 return 1;
478}
479
480static struct bitmap *find_objects(struct rev_info *revs,
481 struct object_list *roots,
482 struct bitmap *seen)
483{
484 struct bitmap *base = NULL;
485 int needs_walk = 0;
486
487 struct object_list *not_mapped = NULL;
488
489 /*
490 * Go through all the roots for the walk. The ones that have bitmaps
491 * on the bitmap index will be `or`ed together to form an initial
492 * global reachability analysis.
493 *
494 * The ones without bitmaps in the index will be stored in the
495 * `not_mapped_list` for further processing.
496 */
497 while (roots) {
498 struct object *object = roots->item;
499 roots = roots->next;
500
501 if (object->type == OBJ_COMMIT) {
502 khiter_t pos = kh_get_sha1(bitmap_git.bitmaps, object->sha1);
503
504 if (pos < kh_end(bitmap_git.bitmaps)) {
505 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
506 struct ewah_bitmap *or_with = lookup_stored_bitmap(st);
507
508 if (base == NULL)
509 base = ewah_to_bitmap(or_with);
510 else
511 bitmap_or_ewah(base, or_with);
512
513 object->flags |= SEEN;
514 continue;
515 }
516 }
517
518 object_list_insert(object, &not_mapped);
519 }
520
521 /*
522 * Best case scenario: We found bitmaps for all the roots,
523 * so the resulting `or` bitmap has the full reachability analysis
524 */
525 if (not_mapped == NULL)
526 return base;
527
528 roots = not_mapped;
529
530 /*
531 * Let's iterate through all the roots that don't have bitmaps to
532 * check if we can determine them to be reachable from the existing
533 * global bitmap.
534 *
535 * If we cannot find them in the existing global bitmap, we'll need
536 * to push them to an actual walk and run it until we can confirm
537 * they are reachable
538 */
539 while (roots) {
540 struct object *object = roots->item;
541 int pos;
542
543 roots = roots->next;
544 pos = bitmap_position(object->sha1);
545
546 if (pos < 0 || base == NULL || !bitmap_get(base, pos)) {
547 object->flags &= ~UNINTERESTING;
548 add_pending_object(revs, object, "");
549 needs_walk = 1;
550 } else {
551 object->flags |= SEEN;
552 }
553 }
554
555 if (needs_walk) {
556 struct include_data incdata;
557
558 if (base == NULL)
559 base = bitmap_new();
560
561 incdata.base = base;
562 incdata.seen = seen;
563
564 revs->include_check = should_include;
565 revs->include_check_data = &incdata;
566
567 if (prepare_revision_walk(revs))
568 die("revision walk setup failed");
569
570 traverse_commit_list(revs, show_commit, show_object, base);
571 }
572
573 return base;
574}
575
576static void show_extended_objects(struct bitmap *objects,
577 show_reachable_fn show_reach)
578{
579 struct eindex *eindex = &bitmap_git.ext_index;
580 uint32_t i;
581
582 for (i = 0; i < eindex->count; ++i) {
583 struct object *obj;
584
585 if (!bitmap_get(objects, bitmap_git.pack->num_objects + i))
586 continue;
587
588 obj = eindex->objects[i];
589 show_reach(obj->sha1, obj->type, 0, eindex->hashes[i], NULL, 0);
590 }
591}
592
593static void show_objects_for_type(
594 struct bitmap *objects,
595 struct ewah_bitmap *type_filter,
596 enum object_type object_type,
597 show_reachable_fn show_reach)
598{
599 size_t pos = 0, i = 0;
600 uint32_t offset;
601
602 struct ewah_iterator it;
603 eword_t filter;
604
605 if (bitmap_git.reuse_objects == bitmap_git.pack->num_objects)
606 return;
607
608 ewah_iterator_init(&it, type_filter);
609
610 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
611 eword_t word = objects->words[i] & filter;
612
613 for (offset = 0; offset < BITS_IN_WORD; ++offset) {
614 const unsigned char *sha1;
615 struct revindex_entry *entry;
616 uint32_t hash = 0;
617
618 if ((word >> offset) == 0)
619 break;
620
621 offset += ewah_bit_ctz64(word >> offset);
622
623 if (pos + offset < bitmap_git.reuse_objects)
624 continue;
625
626 entry = &bitmap_git.reverse_index->revindex[pos + offset];
627 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
628
629 show_reach(sha1, object_type, 0, hash, bitmap_git.pack, entry->offset);
630 }
631
632 pos += BITS_IN_WORD;
633 i++;
634 }
635}
636
637static int in_bitmapped_pack(struct object_list *roots)
638{
639 while (roots) {
640 struct object *object = roots->item;
641 roots = roots->next;
642
643 if (find_pack_entry_one(object->sha1, bitmap_git.pack) > 0)
644 return 1;
645 }
646
647 return 0;
648}
649
650int prepare_bitmap_walk(struct rev_info *revs)
651{
652 unsigned int i;
653 unsigned int pending_nr = revs->pending.nr;
654 struct object_array_entry *pending_e = revs->pending.objects;
655
656 struct object_list *wants = NULL;
657 struct object_list *haves = NULL;
658
659 struct bitmap *wants_bitmap = NULL;
660 struct bitmap *haves_bitmap = NULL;
661
662 if (!bitmap_git.loaded) {
663 /* try to open a bitmapped pack, but don't parse it yet
664 * because we may not need to use it */
665 if (open_pack_bitmap() < 0)
666 return -1;
667 }
668
669 for (i = 0; i < pending_nr; ++i) {
670 struct object *object = pending_e[i].item;
671
672 if (object->type == OBJ_NONE)
673 parse_object_or_die(object->sha1, NULL);
674
675 while (object->type == OBJ_TAG) {
676 struct tag *tag = (struct tag *) object;
677
678 if (object->flags & UNINTERESTING)
679 object_list_insert(object, &haves);
680 else
681 object_list_insert(object, &wants);
682
683 if (!tag->tagged)
684 die("bad tag");
685 object = parse_object_or_die(tag->tagged->sha1, NULL);
686 }
687
688 if (object->flags & UNINTERESTING)
689 object_list_insert(object, &haves);
690 else
691 object_list_insert(object, &wants);
692 }
693
694 /*
695 * if we have a HAVES list, but none of those haves is contained
696 * in the packfile that has a bitmap, we don't have anything to
697 * optimize here
698 */
699 if (haves && !in_bitmapped_pack(haves))
700 return -1;
701
702 /* if we don't want anything, we're done here */
703 if (!wants)
704 return -1;
705
706 /*
707 * now we're going to use bitmaps, so load the actual bitmap entries
708 * from disk. this is the point of no return; after this the rev_list
709 * becomes invalidated and we must perform the revwalk through bitmaps
710 */
711 if (!bitmap_git.loaded && load_pack_bitmap() < 0)
712 return -1;
713
714 revs->pending.nr = 0;
715 revs->pending.alloc = 0;
716 revs->pending.objects = NULL;
717
718 if (haves) {
719 haves_bitmap = find_objects(revs, haves, NULL);
720 reset_revision_walk();
721
722 if (haves_bitmap == NULL)
723 die("BUG: failed to perform bitmap walk");
724 }
725
726 wants_bitmap = find_objects(revs, wants, haves_bitmap);
727
728 if (!wants_bitmap)
729 die("BUG: failed to perform bitmap walk");
730
731 if (haves_bitmap)
732 bitmap_and_not(wants_bitmap, haves_bitmap);
733
734 bitmap_git.result = wants_bitmap;
735
736 bitmap_free(haves_bitmap);
737 return 0;
738}
739
740int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
741 uint32_t *entries,
742 off_t *up_to)
743{
744 /*
745 * Reuse the packfile content if we need more than
746 * 90% of its objects
747 */
748 static const double REUSE_PERCENT = 0.9;
749
750 struct bitmap *result = bitmap_git.result;
751 uint32_t reuse_threshold;
752 uint32_t i, reuse_objects = 0;
753
754 assert(result);
755
756 for (i = 0; i < result->word_alloc; ++i) {
757 if (result->words[i] != (eword_t)~0) {
758 reuse_objects += ewah_bit_ctz64(~result->words[i]);
759 break;
760 }
761
762 reuse_objects += BITS_IN_WORD;
763 }
764
765#ifdef GIT_BITMAP_DEBUG
766 {
767 const unsigned char *sha1;
768 struct revindex_entry *entry;
769
770 entry = &bitmap_git.reverse_index->revindex[reuse_objects];
771 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
772
773 fprintf(stderr, "Failed to reuse at %d (%016llx)\n",
774 reuse_objects, result->words[i]);
775 fprintf(stderr, " %s\n", sha1_to_hex(sha1));
776 }
777#endif
778
779 if (!reuse_objects)
780 return -1;
781
782 if (reuse_objects >= bitmap_git.pack->num_objects) {
783 bitmap_git.reuse_objects = *entries = bitmap_git.pack->num_objects;
784 *up_to = -1; /* reuse the full pack */
785 *packfile = bitmap_git.pack;
786 return 0;
787 }
788
789 reuse_threshold = bitmap_popcount(bitmap_git.result) * REUSE_PERCENT;
790
791 if (reuse_objects < reuse_threshold)
792 return -1;
793
794 bitmap_git.reuse_objects = *entries = reuse_objects;
795 *up_to = bitmap_git.reverse_index->revindex[reuse_objects].offset;
796 *packfile = bitmap_git.pack;
797
798 return 0;
799}
800
801void traverse_bitmap_commit_list(show_reachable_fn show_reachable)
802{
803 assert(bitmap_git.result);
804
805 show_objects_for_type(bitmap_git.result, bitmap_git.commits,
806 OBJ_COMMIT, show_reachable);
807 show_objects_for_type(bitmap_git.result, bitmap_git.trees,
808 OBJ_TREE, show_reachable);
809 show_objects_for_type(bitmap_git.result, bitmap_git.blobs,
810 OBJ_BLOB, show_reachable);
811 show_objects_for_type(bitmap_git.result, bitmap_git.tags,
812 OBJ_TAG, show_reachable);
813
814 show_extended_objects(bitmap_git.result, show_reachable);
815
816 bitmap_free(bitmap_git.result);
817 bitmap_git.result = NULL;
818}
819
820static uint32_t count_object_type(struct bitmap *objects,
821 enum object_type type)
822{
823 struct eindex *eindex = &bitmap_git.ext_index;
824
825 uint32_t i = 0, count = 0;
826 struct ewah_iterator it;
827 eword_t filter;
828
829 switch (type) {
830 case OBJ_COMMIT:
831 ewah_iterator_init(&it, bitmap_git.commits);
832 break;
833
834 case OBJ_TREE:
835 ewah_iterator_init(&it, bitmap_git.trees);
836 break;
837
838 case OBJ_BLOB:
839 ewah_iterator_init(&it, bitmap_git.blobs);
840 break;
841
842 case OBJ_TAG:
843 ewah_iterator_init(&it, bitmap_git.tags);
844 break;
845
846 default:
847 return 0;
848 }
849
850 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
851 eword_t word = objects->words[i++] & filter;
852 count += ewah_bit_popcount64(word);
853 }
854
855 for (i = 0; i < eindex->count; ++i) {
856 if (eindex->objects[i]->type == type &&
857 bitmap_get(objects, bitmap_git.pack->num_objects + i))
858 count++;
859 }
860
861 return count;
862}
863
864void count_bitmap_commit_list(uint32_t *commits, uint32_t *trees,
865 uint32_t *blobs, uint32_t *tags)
866{
867 assert(bitmap_git.result);
868
869 if (commits)
870 *commits = count_object_type(bitmap_git.result, OBJ_COMMIT);
871
872 if (trees)
873 *trees = count_object_type(bitmap_git.result, OBJ_TREE);
874
875 if (blobs)
876 *blobs = count_object_type(bitmap_git.result, OBJ_BLOB);
877
878 if (tags)
879 *tags = count_object_type(bitmap_git.result, OBJ_TAG);
880}
881
882struct bitmap_test_data {
883 struct bitmap *base;
884 struct progress *prg;
885 size_t seen;
886};
887
888static void test_show_object(struct object *object,
889 const struct name_path *path,
890 const char *last, void *data)
891{
892 struct bitmap_test_data *tdata = data;
893 int bitmap_pos;
894
895 bitmap_pos = bitmap_position(object->sha1);
896 if (bitmap_pos < 0)
897 die("Object not in bitmap: %s\n", sha1_to_hex(object->sha1));
898
899 bitmap_set(tdata->base, bitmap_pos);
900 display_progress(tdata->prg, ++tdata->seen);
901}
902
903static void test_show_commit(struct commit *commit, void *data)
904{
905 struct bitmap_test_data *tdata = data;
906 int bitmap_pos;
907
908 bitmap_pos = bitmap_position(commit->object.sha1);
909 if (bitmap_pos < 0)
910 die("Object not in bitmap: %s\n", sha1_to_hex(commit->object.sha1));
911
912 bitmap_set(tdata->base, bitmap_pos);
913 display_progress(tdata->prg, ++tdata->seen);
914}
915
916void test_bitmap_walk(struct rev_info *revs)
917{
918 struct object *root;
919 struct bitmap *result = NULL;
920 khiter_t pos;
921 size_t result_popcnt;
922 struct bitmap_test_data tdata;
923
924 if (prepare_bitmap_git())
925 die("failed to load bitmap indexes");
926
927 if (revs->pending.nr != 1)
928 die("you must specify exactly one commit to test");
929
930 fprintf(stderr, "Bitmap v%d test (%d entries loaded)\n",
931 bitmap_git.version, bitmap_git.entry_count);
932
933 root = revs->pending.objects[0].item;
934 pos = kh_get_sha1(bitmap_git.bitmaps, root->sha1);
935
936 if (pos < kh_end(bitmap_git.bitmaps)) {
937 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
938 struct ewah_bitmap *bm = lookup_stored_bitmap(st);
939
940 fprintf(stderr, "Found bitmap for %s. %d bits / %08x checksum\n",
941 sha1_to_hex(root->sha1), (int)bm->bit_size, ewah_checksum(bm));
942
943 result = ewah_to_bitmap(bm);
944 }
945
946 if (result == NULL)
947 die("Commit %s doesn't have an indexed bitmap", sha1_to_hex(root->sha1));
948
949 revs->tag_objects = 1;
950 revs->tree_objects = 1;
951 revs->blob_objects = 1;
952
953 result_popcnt = bitmap_popcount(result);
954
955 if (prepare_revision_walk(revs))
956 die("revision walk setup failed");
957
958 tdata.base = bitmap_new();
959 tdata.prg = start_progress("Verifying bitmap entries", result_popcnt);
960 tdata.seen = 0;
961
962 traverse_commit_list(revs, &test_show_commit, &test_show_object, &tdata);
963
964 stop_progress(&tdata.prg);
965
966 if (bitmap_equals(result, tdata.base))
967 fprintf(stderr, "OK!\n");
968 else
969 fprintf(stderr, "Mismatch!\n");
970}
7cc8f971
VM
971
972static int rebuild_bitmap(uint32_t *reposition,
973 struct ewah_bitmap *source,
974 struct bitmap *dest)
975{
976 uint32_t pos = 0;
977 struct ewah_iterator it;
978 eword_t word;
979
980 ewah_iterator_init(&it, source);
981
982 while (ewah_iterator_next(&word, &it)) {
983 uint32_t offset, bit_pos;
984
985 for (offset = 0; offset < BITS_IN_WORD; ++offset) {
986 if ((word >> offset) == 0)
987 break;
988
989 offset += ewah_bit_ctz64(word >> offset);
990
991 bit_pos = reposition[pos + offset];
992 if (bit_pos > 0)
993 bitmap_set(dest, bit_pos - 1);
994 else /* can't reuse, we don't have the object */
995 return -1;
996 }
997
998 pos += BITS_IN_WORD;
999 }
1000 return 0;
1001}
1002
1003int rebuild_existing_bitmaps(struct packing_data *mapping,
1004 khash_sha1 *reused_bitmaps,
1005 int show_progress)
1006{
1007 uint32_t i, num_objects;
1008 uint32_t *reposition;
1009 struct bitmap *rebuild;
1010 struct stored_bitmap *stored;
1011 struct progress *progress = NULL;
1012
1013 khiter_t hash_pos;
1014 int hash_ret;
1015
1016 if (prepare_bitmap_git() < 0)
1017 return -1;
1018
1019 num_objects = bitmap_git.pack->num_objects;
1020 reposition = xcalloc(num_objects, sizeof(uint32_t));
1021
1022 for (i = 0; i < num_objects; ++i) {
1023 const unsigned char *sha1;
1024 struct revindex_entry *entry;
1025 struct object_entry *oe;
1026
1027 entry = &bitmap_git.reverse_index->revindex[i];
1028 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
1029 oe = packlist_find(mapping, sha1, NULL);
1030
1031 if (oe)
1032 reposition[i] = oe->in_pack_pos + 1;
1033 }
1034
1035 rebuild = bitmap_new();
1036 i = 0;
1037
1038 if (show_progress)
1039 progress = start_progress("Reusing bitmaps", 0);
1040
1041 kh_foreach_value(bitmap_git.bitmaps, stored, {
1042 if (stored->flags & BITMAP_FLAG_REUSE) {
1043 if (!rebuild_bitmap(reposition,
1044 lookup_stored_bitmap(stored),
1045 rebuild)) {
1046 hash_pos = kh_put_sha1(reused_bitmaps,
1047 stored->sha1,
1048 &hash_ret);
1049 kh_value(reused_bitmaps, hash_pos) =
1050 bitmap_to_ewah(rebuild);
1051 }
1052 bitmap_reset(rebuild);
1053 display_progress(progress, ++i);
1054 }
1055 });
1056
1057 stop_progress(&progress);
1058
1059 free(reposition);
1060 bitmap_free(rebuild);
1061 return 0;
1062}