| #include "cache.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" |
| |
| 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; |
| |
| khash_sha1 *bitmaps; |
| khash_sha1 *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[20]; |
| }; |
| |
| 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 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(); |
| |
| for (i = 0; i < index_nr; ++i) { |
| struct object_entry *entry = (struct object_entry *)index[i]; |
| enum object_type real_type; |
| |
| entry->in_pack_pos = i; |
| |
| switch (entry->type) { |
| case OBJ_COMMIT: |
| case OBJ_TREE: |
| case OBJ_BLOB: |
| case OBJ_TAG: |
| real_type = entry->type; |
| break; |
| |
| default: |
| real_type = sha1_object_info(entry->idx.sha1, 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)", |
| sha1_to_hex(entry->idx.sha1), real_type, entry->type); |
| } |
| } |
| } |
| |
| /** |
| * 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 unsigned char *sha1) |
| { |
| struct object_entry *entry = packlist_find(writer.to_pack, sha1, NULL); |
| |
| if (!entry) { |
| die("Failed to write bitmap index. Packfile doesn't have full closure " |
| "(object %s is missing)", sha1_to_hex(sha1)); |
| } |
| |
| return entry->in_pack_pos; |
| } |
| |
| static void show_object(struct object *object, const char *name, void *data) |
| { |
| struct bitmap *base = data; |
| bitmap_set(base, find_object_pos(object->oid.hash)); |
| 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.hash); |
| |
| if (bitmap_get(base, bitmap_pos)) |
| return 0; |
| |
| hash_pos = kh_get_sha1(writer.bitmaps, commit->object.oid.hash); |
| 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_sha1(); |
| writer.to_pack = to_pack; |
| |
| if (writer.show_progress) |
| writer.progress = start_progress("Building bitmaps", writer.selected_nr); |
| |
| init_revisions(&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); |
| |
| revs.pending.nr = 0; |
| revs.pending.alloc = 0; |
| revs.pending.objects = NULL; |
| |
| 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_sha1(writer.bitmaps, object->oid.hash, &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) |
| { |
| if (prepare_bitmap_git() < 0) |
| return; |
| |
| writer.reused = kh_init_sha1(); |
| rebuild_existing_bitmaps(to_pack, writer.reused, writer.show_progress); |
| } |
| |
| static struct ewah_bitmap *find_reused_bitmap(const unsigned char *sha1) |
| { |
| khiter_t hash_pos; |
| |
| if (!writer.reused) |
| return NULL; |
| |
| hash_pos = kh_get_sha1(writer.reused, sha1); |
| 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.hash); |
| } 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.hash); |
| 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 sha1write_ewah_helper(void *f, const void *buf, size_t len) |
| { |
| /* sha1write will die on error */ |
| sha1write(f, buf, len); |
| return len; |
| } |
| |
| /** |
| * Write the bitmap index to disk |
| */ |
| static inline void dump_bitmap(struct sha1file *f, struct ewah_bitmap *bitmap) |
| { |
| if (ewah_serialize_to(bitmap, sha1write_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]->sha1; |
| } |
| |
| static void write_selected_commits_v1(struct sha1file *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) |
| die("BUG: trying to write commit not in index"); |
| |
| sha1write_be32(f, commit_pos); |
| sha1write_u8(f, stored->xor_offset); |
| sha1write_u8(f, stored->flags); |
| |
| dump_bitmap(f, stored->write_as); |
| } |
| } |
| |
| static void write_hash_cache(struct sha1file *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); |
| sha1write(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 char tmp_file[PATH_MAX]; |
| static uint16_t default_version = 1; |
| static uint16_t flags = BITMAP_OPT_FULL_DAG; |
| struct sha1file *f; |
| |
| struct bitmap_disk_header header; |
| |
| int fd = odb_mkstemp(tmp_file, sizeof(tmp_file), "pack/tmp_bitmap_XXXXXX"); |
| |
| if (fd < 0) |
| die_errno("unable to create '%s'", tmp_file); |
| f = sha1fd(fd, tmp_file); |
| |
| 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); |
| |
| sha1write(f, &header, sizeof(header)); |
| 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); |
| |
| sha1close(f, NULL, CSUM_FSYNC); |
| |
| if (adjust_shared_perm(tmp_file)) |
| die_errno("unable to make temporary bitmap file readable"); |
| |
| if (rename(tmp_file, filename)) |
| die_errno("unable to rename temporary bitmap file to '%s'", filename); |
| } |