diff options
Diffstat (limited to 'third_party/git/pack-bitmap-write.c')
| -rw-r--r-- | third_party/git/pack-bitmap-write.c | 557 |
1 files changed, 0 insertions, 557 deletions
diff --git a/third_party/git/pack-bitmap-write.c b/third_party/git/pack-bitmap-write.c deleted file mode 100644 index fa78a460c9..0000000000 --- a/third_party/git/pack-bitmap-write.c +++ /dev/null @@ -1,557 +0,0 @@ -#include "cache.h" -#include "object-store.h" -#include "commit.h" -#include "tag.h" -#include "diff.h" -#include "revision.h" -#include "list-objects.h" -#include "progress.h" -#include "pack-revindex.h" -#include "pack.h" -#include "pack-bitmap.h" -#include "sha1-lookup.h" -#include "pack-objects.h" -#include "commit-reach.h" - -struct bitmapped_commit { - struct commit *commit; - struct ewah_bitmap *bitmap; - struct ewah_bitmap *write_as; - int flags; - int xor_offset; - uint32_t commit_pos; -}; - -struct bitmap_writer { - struct ewah_bitmap *commits; - struct ewah_bitmap *trees; - struct ewah_bitmap *blobs; - struct ewah_bitmap *tags; - - kh_oid_map_t *bitmaps; - kh_oid_map_t *reused; - struct packing_data *to_pack; - - struct bitmapped_commit *selected; - unsigned int selected_nr, selected_alloc; - - struct progress *progress; - int show_progress; - unsigned char pack_checksum[GIT_MAX_RAWSZ]; -}; - -static struct bitmap_writer writer; - -void bitmap_writer_show_progress(int show) -{ - writer.show_progress = show; -} - -/** - * Build the initial type index for the packfile - */ -void bitmap_writer_build_type_index(struct packing_data *to_pack, - struct pack_idx_entry **index, - uint32_t index_nr) -{ - uint32_t i; - - writer.commits = ewah_new(); - writer.trees = ewah_new(); - writer.blobs = ewah_new(); - writer.tags = ewah_new(); - ALLOC_ARRAY(to_pack->in_pack_pos, to_pack->nr_objects); - - for (i = 0; i < index_nr; ++i) { - struct object_entry *entry = (struct object_entry *)index[i]; - enum object_type real_type; - - oe_set_in_pack_pos(to_pack, entry, i); - - switch (oe_type(entry)) { - case OBJ_COMMIT: - case OBJ_TREE: - case OBJ_BLOB: - case OBJ_TAG: - real_type = oe_type(entry); - break; - - default: - real_type = oid_object_info(to_pack->repo, - &entry->idx.oid, NULL); - break; - } - - switch (real_type) { - case OBJ_COMMIT: - ewah_set(writer.commits, i); - break; - - case OBJ_TREE: - ewah_set(writer.trees, i); - break; - - case OBJ_BLOB: - ewah_set(writer.blobs, i); - break; - - case OBJ_TAG: - ewah_set(writer.tags, i); - break; - - default: - die("Missing type information for %s (%d/%d)", - oid_to_hex(&entry->idx.oid), real_type, - oe_type(entry)); - } - } -} - -/** - * Compute the actual bitmaps - */ -static struct object **seen_objects; -static unsigned int seen_objects_nr, seen_objects_alloc; - -static inline void push_bitmapped_commit(struct commit *commit, struct ewah_bitmap *reused) -{ - if (writer.selected_nr >= writer.selected_alloc) { - writer.selected_alloc = (writer.selected_alloc + 32) * 2; - REALLOC_ARRAY(writer.selected, writer.selected_alloc); - } - - writer.selected[writer.selected_nr].commit = commit; - writer.selected[writer.selected_nr].bitmap = reused; - writer.selected[writer.selected_nr].flags = 0; - - writer.selected_nr++; -} - -static inline void mark_as_seen(struct object *object) -{ - ALLOC_GROW(seen_objects, seen_objects_nr + 1, seen_objects_alloc); - seen_objects[seen_objects_nr++] = object; -} - -static inline void reset_all_seen(void) -{ - unsigned int i; - for (i = 0; i < seen_objects_nr; ++i) { - seen_objects[i]->flags &= ~(SEEN | ADDED | SHOWN); - } - seen_objects_nr = 0; -} - -static uint32_t find_object_pos(const struct object_id *oid) -{ - struct object_entry *entry = packlist_find(writer.to_pack, oid, NULL); - - if (!entry) { - die("Failed to write bitmap index. Packfile doesn't have full closure " - "(object %s is missing)", oid_to_hex(oid)); - } - - return oe_in_pack_pos(writer.to_pack, entry); -} - -static void show_object(struct object *object, const char *name, void *data) -{ - struct bitmap *base = data; - bitmap_set(base, find_object_pos(&object->oid)); - mark_as_seen(object); -} - -static void show_commit(struct commit *commit, void *data) -{ - mark_as_seen((struct object *)commit); -} - -static int -add_to_include_set(struct bitmap *base, struct commit *commit) -{ - khiter_t hash_pos; - uint32_t bitmap_pos = find_object_pos(&commit->object.oid); - - if (bitmap_get(base, bitmap_pos)) - return 0; - - hash_pos = kh_get_oid_map(writer.bitmaps, commit->object.oid); - if (hash_pos < kh_end(writer.bitmaps)) { - struct bitmapped_commit *bc = kh_value(writer.bitmaps, hash_pos); - bitmap_or_ewah(base, bc->bitmap); - return 0; - } - - bitmap_set(base, bitmap_pos); - return 1; -} - -static int -should_include(struct commit *commit, void *_data) -{ - struct bitmap *base = _data; - - if (!add_to_include_set(base, commit)) { - struct commit_list *parent = commit->parents; - - mark_as_seen((struct object *)commit); - - while (parent) { - parent->item->object.flags |= SEEN; - mark_as_seen((struct object *)parent->item); - parent = parent->next; - } - - return 0; - } - - return 1; -} - -static void compute_xor_offsets(void) -{ - static const int MAX_XOR_OFFSET_SEARCH = 10; - - int i, next = 0; - - while (next < writer.selected_nr) { - struct bitmapped_commit *stored = &writer.selected[next]; - - int best_offset = 0; - struct ewah_bitmap *best_bitmap = stored->bitmap; - struct ewah_bitmap *test_xor; - - for (i = 1; i <= MAX_XOR_OFFSET_SEARCH; ++i) { - int curr = next - i; - - if (curr < 0) - break; - - test_xor = ewah_pool_new(); - ewah_xor(writer.selected[curr].bitmap, stored->bitmap, test_xor); - - if (test_xor->buffer_size < best_bitmap->buffer_size) { - if (best_bitmap != stored->bitmap) - ewah_pool_free(best_bitmap); - - best_bitmap = test_xor; - best_offset = i; - } else { - ewah_pool_free(test_xor); - } - } - - stored->xor_offset = best_offset; - stored->write_as = best_bitmap; - - next++; - } -} - -void bitmap_writer_build(struct packing_data *to_pack) -{ - static const double REUSE_BITMAP_THRESHOLD = 0.2; - - int i, reuse_after, need_reset; - struct bitmap *base = bitmap_new(); - struct rev_info revs; - - writer.bitmaps = kh_init_oid_map(); - writer.to_pack = to_pack; - - if (writer.show_progress) - writer.progress = start_progress("Building bitmaps", writer.selected_nr); - - repo_init_revisions(to_pack->repo, &revs, NULL); - revs.tag_objects = 1; - revs.tree_objects = 1; - revs.blob_objects = 1; - revs.no_walk = 0; - - revs.include_check = should_include; - reset_revision_walk(); - - reuse_after = writer.selected_nr * REUSE_BITMAP_THRESHOLD; - need_reset = 0; - - for (i = writer.selected_nr - 1; i >= 0; --i) { - struct bitmapped_commit *stored; - struct object *object; - - khiter_t hash_pos; - int hash_ret; - - stored = &writer.selected[i]; - object = (struct object *)stored->commit; - - if (stored->bitmap == NULL) { - if (i < writer.selected_nr - 1 && - (need_reset || - !in_merge_bases(writer.selected[i + 1].commit, - stored->commit))) { - bitmap_reset(base); - reset_all_seen(); - } - - add_pending_object(&revs, object, ""); - revs.include_check_data = base; - - if (prepare_revision_walk(&revs)) - die("revision walk setup failed"); - - traverse_commit_list(&revs, show_commit, show_object, base); - - object_array_clear(&revs.pending); - - stored->bitmap = bitmap_to_ewah(base); - need_reset = 0; - } else - need_reset = 1; - - if (i >= reuse_after) - stored->flags |= BITMAP_FLAG_REUSE; - - hash_pos = kh_put_oid_map(writer.bitmaps, object->oid, &hash_ret); - if (hash_ret == 0) - die("Duplicate entry when writing index: %s", - oid_to_hex(&object->oid)); - - kh_value(writer.bitmaps, hash_pos) = stored; - display_progress(writer.progress, writer.selected_nr - i); - } - - bitmap_free(base); - stop_progress(&writer.progress); - - compute_xor_offsets(); -} - -/** - * Select the commits that will be bitmapped - */ -static inline unsigned int next_commit_index(unsigned int idx) -{ - static const unsigned int MIN_COMMITS = 100; - static const unsigned int MAX_COMMITS = 5000; - - static const unsigned int MUST_REGION = 100; - static const unsigned int MIN_REGION = 20000; - - unsigned int offset, next; - - if (idx <= MUST_REGION) - return 0; - - if (idx <= MIN_REGION) { - offset = idx - MUST_REGION; - return (offset < MIN_COMMITS) ? offset : MIN_COMMITS; - } - - offset = idx - MIN_REGION; - next = (offset < MAX_COMMITS) ? offset : MAX_COMMITS; - - return (next > MIN_COMMITS) ? next : MIN_COMMITS; -} - -static int date_compare(const void *_a, const void *_b) -{ - struct commit *a = *(struct commit **)_a; - struct commit *b = *(struct commit **)_b; - return (long)b->date - (long)a->date; -} - -void bitmap_writer_reuse_bitmaps(struct packing_data *to_pack) -{ - struct bitmap_index *bitmap_git; - if (!(bitmap_git = prepare_bitmap_git(to_pack->repo))) - return; - - writer.reused = kh_init_oid_map(); - rebuild_existing_bitmaps(bitmap_git, to_pack, writer.reused, - writer.show_progress); - /* - * NEEDSWORK: rebuild_existing_bitmaps() makes writer.reused reference - * some bitmaps in bitmap_git, so we can't free the latter. - */ -} - -static struct ewah_bitmap *find_reused_bitmap(const struct object_id *oid) -{ - khiter_t hash_pos; - - if (!writer.reused) - return NULL; - - hash_pos = kh_get_oid_map(writer.reused, *oid); - if (hash_pos >= kh_end(writer.reused)) - return NULL; - - return kh_value(writer.reused, hash_pos); -} - -void bitmap_writer_select_commits(struct commit **indexed_commits, - unsigned int indexed_commits_nr, - int max_bitmaps) -{ - unsigned int i = 0, j, next; - - QSORT(indexed_commits, indexed_commits_nr, date_compare); - - if (writer.show_progress) - writer.progress = start_progress("Selecting bitmap commits", 0); - - if (indexed_commits_nr < 100) { - for (i = 0; i < indexed_commits_nr; ++i) - push_bitmapped_commit(indexed_commits[i], NULL); - return; - } - - for (;;) { - struct ewah_bitmap *reused_bitmap = NULL; - struct commit *chosen = NULL; - - next = next_commit_index(i); - - if (i + next >= indexed_commits_nr) - break; - - if (max_bitmaps > 0 && writer.selected_nr >= max_bitmaps) { - writer.selected_nr = max_bitmaps; - break; - } - - if (next == 0) { - chosen = indexed_commits[i]; - reused_bitmap = find_reused_bitmap(&chosen->object.oid); - } else { - chosen = indexed_commits[i + next]; - - for (j = 0; j <= next; ++j) { - struct commit *cm = indexed_commits[i + j]; - - reused_bitmap = find_reused_bitmap(&cm->object.oid); - if (reused_bitmap || (cm->object.flags & NEEDS_BITMAP) != 0) { - chosen = cm; - break; - } - - if (cm->parents && cm->parents->next) - chosen = cm; - } - } - - push_bitmapped_commit(chosen, reused_bitmap); - - i += next + 1; - display_progress(writer.progress, i); - } - - stop_progress(&writer.progress); -} - - -static int hashwrite_ewah_helper(void *f, const void *buf, size_t len) -{ - /* hashwrite will die on error */ - hashwrite(f, buf, len); - return len; -} - -/** - * Write the bitmap index to disk - */ -static inline void dump_bitmap(struct hashfile *f, struct ewah_bitmap *bitmap) -{ - if (ewah_serialize_to(bitmap, hashwrite_ewah_helper, f) < 0) - die("Failed to write bitmap index"); -} - -static const unsigned char *sha1_access(size_t pos, void *table) -{ - struct pack_idx_entry **index = table; - return index[pos]->oid.hash; -} - -static void write_selected_commits_v1(struct hashfile *f, - struct pack_idx_entry **index, - uint32_t index_nr) -{ - int i; - - for (i = 0; i < writer.selected_nr; ++i) { - struct bitmapped_commit *stored = &writer.selected[i]; - - int commit_pos = - sha1_pos(stored->commit->object.oid.hash, index, index_nr, sha1_access); - - if (commit_pos < 0) - BUG("trying to write commit not in index"); - - hashwrite_be32(f, commit_pos); - hashwrite_u8(f, stored->xor_offset); - hashwrite_u8(f, stored->flags); - - dump_bitmap(f, stored->write_as); - } -} - -static void write_hash_cache(struct hashfile *f, - struct pack_idx_entry **index, - uint32_t index_nr) -{ - uint32_t i; - - for (i = 0; i < index_nr; ++i) { - struct object_entry *entry = (struct object_entry *)index[i]; - uint32_t hash_value = htonl(entry->hash); - hashwrite(f, &hash_value, sizeof(hash_value)); - } -} - -void bitmap_writer_set_checksum(unsigned char *sha1) -{ - hashcpy(writer.pack_checksum, sha1); -} - -void bitmap_writer_finish(struct pack_idx_entry **index, - uint32_t index_nr, - const char *filename, - uint16_t options) -{ - static uint16_t default_version = 1; - static uint16_t flags = BITMAP_OPT_FULL_DAG; - struct strbuf tmp_file = STRBUF_INIT; - struct hashfile *f; - - struct bitmap_disk_header header; - - int fd = odb_mkstemp(&tmp_file, "pack/tmp_bitmap_XXXXXX"); - - f = hashfd(fd, tmp_file.buf); - - memcpy(header.magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE)); - header.version = htons(default_version); - header.options = htons(flags | options); - header.entry_count = htonl(writer.selected_nr); - hashcpy(header.checksum, writer.pack_checksum); - - hashwrite(f, &header, sizeof(header) - GIT_MAX_RAWSZ + the_hash_algo->rawsz); - dump_bitmap(f, writer.commits); - dump_bitmap(f, writer.trees); - dump_bitmap(f, writer.blobs); - dump_bitmap(f, writer.tags); - write_selected_commits_v1(f, index, index_nr); - - if (options & BITMAP_OPT_HASH_CACHE) - write_hash_cache(f, index, index_nr); - - finalize_hashfile(f, NULL, CSUM_HASH_IN_STREAM | CSUM_FSYNC | CSUM_CLOSE); - - if (adjust_shared_perm(tmp_file.buf)) - die_errno("unable to make temporary bitmap file readable"); - - if (rename(tmp_file.buf, filename)) - die_errno("unable to rename temporary bitmap file to '%s'", filename); - - strbuf_release(&tmp_file); -} |