Signed-off-by: Jonathan Tan <jonathantanmy@xxxxxxxxxx> --- builtin/index-pack.c | 267 ++++++++++++++++++++----------------------- 1 file changed, 127 insertions(+), 140 deletions(-) diff --git a/builtin/index-pack.c b/builtin/index-pack.c index 3908cd3115..f6318037ca 100644 --- a/builtin/index-pack.c +++ b/builtin/index-pack.c @@ -38,15 +38,22 @@ struct base_data { struct object_entry *obj; int ref_first, ref_last; int ofs_first, ofs_last; + int retain_data; + int children_remaining; /* Not initialized by make_base(). */ + struct list_head list; void *data; unsigned long size; }; +LIST_HEAD(work_head); +LIST_HEAD(done_head); +size_t base_cache_used; +size_t base_cache_limit; + struct thread_local { pthread_t thread; - size_t base_cache_used; int pack_fd; }; @@ -369,36 +376,38 @@ static void free_base_data(struct base_data *c) { if (c->data) { FREE_AND_NULL(c->data); - get_thread_data()->base_cache_used -= c->size; + base_cache_used -= c->size; } } -static void prune_base_data(struct base_data *youngest_child) +static void prune_base_data(struct base_data *retain) { - struct base_data *b; - struct thread_local *data = get_thread_data(); - struct base_data **ancestry = NULL; - int nr = 0, alloc = 0; - int i; + struct list_head *pos; - if (data->base_cache_used <= delta_base_cache_limit) + if (base_cache_used <= base_cache_limit) return; - /* - * Free all ancestors of youngest_child until we have enough space, - * starting with the oldest. (We cannot free youngest_child itself.) - */ - for (b = youngest_child->base; b != NULL; b = b->base) { - ALLOC_GROW(ancestry, nr + 1, alloc); - ancestry[nr++] = b; + list_for_each_prev(pos, &done_head) { + struct base_data *b = list_entry(pos, struct base_data, list); + if (b->retain_data || b == retain) + continue; + if (b->data) { + free_base_data(b); + if (base_cache_used <= base_cache_limit) + return; + } } - for (i = nr - 1; - i >= 0 && data->base_cache_used > delta_base_cache_limit; - i--) { - if (ancestry[i]->data) - free_base_data(ancestry[i]); + + list_for_each_prev(pos, &work_head) { + struct base_data *b = list_entry(pos, struct base_data, list); + if (b->retain_data || b == retain) + continue; + if (b->data) { + free_base_data(b); + if (base_cache_used <= base_cache_limit) + return; + } } - free(ancestry); } static int is_delta_type(enum object_type type) @@ -886,7 +895,7 @@ static void *get_base_data(struct base_data *c) if (!delta_nr) { c->data = get_data_from_pack(obj); c->size = obj->size; - get_thread_data()->base_cache_used += c->size; + base_cache_used += c->size; prune_base_data(c); } for (; delta_nr > 0; delta_nr--) { @@ -902,7 +911,7 @@ static void *get_base_data(struct base_data *c) free(raw); if (!c->data) bad_object(obj->idx.offset, _("failed to apply delta")); - get_thread_data()->base_cache_used += c->size; + base_cache_used += c->size; prune_base_data(c); } free(delta); @@ -920,6 +929,8 @@ static struct base_data *make_base(struct object_entry *obj, &base->ref_first, &base->ref_last); find_ofs_delta_children(obj->idx.offset, &base->ofs_first, &base->ofs_last); + base->children_remaining = base->ref_last - base->ref_first + + base->ofs_last - base->ofs_first + 2; return base; } @@ -953,14 +964,8 @@ static struct base_data *resolve_delta(struct object_entry *delta_obj, &delta_obj->idx.oid); result = make_base(delta_obj, base); - if (result->ref_last == -1 && result->ofs_last == -1) { - free(result_data); - } else { - result->data = result_data; - result->size = result_size; - get_thread_data()->base_cache_used += result->size; - prune_base_data(result); - } + result->data = result_data; + result->size = result_size; counter_lock(); nr_resolved_deltas++; @@ -969,84 +974,6 @@ static struct base_data *resolve_delta(struct object_entry *delta_obj, return result; } -/* - * Standard boolean compare-and-swap: atomically check whether "*type" is - * "want"; if so, swap in "set" and return true. Otherwise, leave it untouched - * and return false. - */ -static int compare_and_swap_type(signed char *type, - enum object_type want, - enum object_type set) -{ - enum object_type old; - - type_cas_lock(); - old = *type; - if (old == want) - *type = set; - type_cas_unlock(); - - return old == want; -} - -static struct base_data *find_unresolved_deltas_1(struct base_data *base, - struct base_data *prev_base) -{ - if (base->ref_first <= base->ref_last) { - struct object_entry *child = objects + ref_deltas[base->ref_first].obj_no; - struct base_data *result; - - if (!compare_and_swap_type(&child->real_type, OBJ_REF_DELTA, - base->obj->real_type)) - BUG("child->real_type != OBJ_REF_DELTA"); - - get_base_data(base); - result = resolve_delta(child, base); - if (base->ref_first == base->ref_last && base->ofs_last == -1) - free_base_data(base); - - base->ref_first++; - return result; - } - - if (base->ofs_first <= base->ofs_last) { - struct object_entry *child = objects + ofs_deltas[base->ofs_first].obj_no; - struct base_data *result; - - assert(child->real_type == OBJ_OFS_DELTA); - child->real_type = base->obj->real_type; - get_base_data(base); - result = resolve_delta(child, base); - if (base->ofs_first == base->ofs_last) - free_base_data(base); - - base->ofs_first++; - return result; - } - - free_base_data(base); - return NULL; -} - -static void find_unresolved_deltas(struct base_data *base) -{ - struct base_data *new_base, *prev_base = NULL; - for (;;) { - new_base = find_unresolved_deltas_1(base, prev_base); - - if (new_base) { - prev_base = base; - base = new_base; - } else { - free(base); - base = prev_base; - if (!base) - return; - prev_base = base->base; - } - } -} - static int compare_ofs_delta_entry(const void *a, const void *b) { const struct ofs_delta_entry *delta_a = a; @@ -1065,33 +992,97 @@ static int compare_ref_delta_entry(const void *a, const void *b) return oidcmp(&delta_a->oid, &delta_b->oid); } -static void resolve_base(struct object_entry *obj) +static void *do_work(void *data) { - struct base_data *base_obj = make_base(obj, NULL); - - find_unresolved_deltas(base_obj); -} - -static void *threaded_second_pass(void *data) -{ - set_thread_data(data); + if (data) + set_thread_data(data); for (;;) { - int i; - counter_lock(); - display_progress(progress, nr_resolved_deltas); - counter_unlock(); + struct base_data *parent = NULL; + struct object_entry *child_obj; + struct base_data *child; + work_lock(); - while (nr_dispatched < nr_objects && - is_delta_type(objects[nr_dispatched].type)) - nr_dispatched++; - if (nr_dispatched >= nr_objects) { - work_unlock(); - break; + if (list_empty(&work_head)) { + while (nr_dispatched < nr_objects && + is_delta_type(objects[nr_dispatched].type)) + nr_dispatched++; + if (nr_dispatched >= nr_objects) { + work_unlock(); + break; + } + child_obj = &objects[nr_dispatched++]; + } else { + parent = list_first_entry(&work_head, struct base_data, + list); + + if (parent->ref_first <= parent->ref_last) { + child_obj = objects + + ref_deltas[parent->ref_first++].obj_no; + assert(child_obj->real_type == OBJ_REF_DELTA); + child_obj->real_type = parent->obj->real_type; + } else { + child_obj = objects + + ofs_deltas[parent->ofs_first++].obj_no; + assert(child_obj->real_type == OBJ_OFS_DELTA); + child_obj->real_type = parent->obj->real_type; + } + + if (parent->ref_first > parent->ref_last && + parent->ofs_first > parent->ofs_last) { + list_del(&parent->list); + list_add(&parent->list, &done_head); + } + + get_base_data(parent); + parent->retain_data++; } - i = nr_dispatched++; work_unlock(); - resolve_base(&objects[i]); + if (parent) { + child = resolve_delta(child_obj, parent); + if (!child->children_remaining) + FREE_AND_NULL(child->data); + } else { + child = make_base(child_obj, NULL); + if (child->children_remaining) { + /* + * Since this child has its own delta children, + * we will need this data in the future. + * Inflate now so that future iterations will + * have access to this object's data while + * outside the work mutex. + */ + child->data = get_data_from_pack(child_obj); + child->size = child_obj->size; + } + } + + work_lock(); + if (parent) + parent->retain_data--; + if (child->data) { + list_add(&child->list, &work_head); + base_cache_used += child->size; + prune_base_data(NULL); + } else { + struct base_data *p = parent; + + while (p) { + struct base_data *next_p; + + p->children_remaining--; + if (p->children_remaining) + break; + + next_p = p->base; + free_base_data(p); + list_del(&p->list); + free(p); + + p = next_p; + } + } + work_unlock(); } return NULL; } @@ -1192,11 +1183,12 @@ static void resolve_deltas(void) nr_ref_deltas + nr_ofs_deltas); nr_dispatched = 0; + base_cache_limit = delta_base_cache_limit * nr_threads; if (nr_threads > 1 || getenv("GIT_FORCE_THREADS")) { init_thread(); for (i = 0; i < nr_threads; i++) { int ret = pthread_create(&thread_data[i].thread, NULL, - threaded_second_pass, thread_data + i); + do_work, thread_data + i); if (ret) die(_("unable to create thread: %s"), strerror(ret)); @@ -1206,7 +1198,7 @@ static void resolve_deltas(void) cleanup_thread(); return; } - threaded_second_pass(¬hread_data); + do_work(¬hread_data); } /* @@ -1362,10 +1354,8 @@ static void fix_unresolved_deltas(struct hashfile *f) for (i = 0; i < nr_ref_deltas; i++) { struct ref_delta_entry *d = sorted_by_pos[i]; enum object_type type; - struct base_data *base; void *data; unsigned long size; - struct object_entry *obj; if (objects[d->obj_no].real_type != OBJ_REF_DELTA) continue; @@ -1376,11 +1366,8 @@ static void fix_unresolved_deltas(struct hashfile *f) if (check_object_signature(&d->oid, data, size, type_name(type))) die(_("local object %s is corrupt"), oid_to_hex(&d->oid)); - obj = append_obj_to_pack(f, d->oid.hash, data, size, type); - base = make_base(obj, NULL); - base->data = data; - base->size = size; - find_unresolved_deltas(base); + append_obj_to_pack(f, d->oid.hash, data, size, type); + do_work(NULL); /* will pick up new object in objects array (added by append_obj_to_pack) */ display_progress(progress, nr_resolved_deltas); } free(sorted_by_pos); -- 2.23.0.581.g78d2f28ef7-goog