From 6dc5ef759f25fbded11d235362c59f59498809e6 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Tue, 8 Dec 2020 17:04:03 -0500 Subject: pack-bitmap-write: fill bitmap with commit history The current implementation of bitmap_writer_build() creates a reachability bitmap for every walked commit. After computing a bitmap for a commit, those bits are pushed to an in-progress bitmap for its children. fill_bitmap_commit() assumes the bits corresponding to objects reachable from the parents of a commit are already set. This means that when visiting a new commit, we only have to walk the objects reachable between it and any of its parents. A future change to bitmap_writer_build() will relax this condition so not all parents have their bits set. Prepare for that by having 'fill_bitmap_commit()' walk parents until reaching commits whose bits are already set. Then, walk the trees for these commits as well. This has no functional change with the current implementation of bitmap_writer_build(). Signed-off-by: Derrick Stolee Signed-off-by: Taylor Blau Signed-off-by: Junio C Hamano --- pack-bitmap-write.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) (limited to 'pack-bitmap-write.c') diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c index 1eb9615df8..957639241e 100644 --- a/pack-bitmap-write.c +++ b/pack-bitmap-write.c @@ -12,6 +12,7 @@ #include "sha1-lookup.h" #include "pack-objects.h" #include "commit-reach.h" +#include "prio-queue.h" struct bitmapped_commit { struct commit *commit; @@ -279,17 +280,30 @@ static void fill_bitmap_tree(struct bitmap *bitmap, } static void fill_bitmap_commit(struct bb_commit *ent, - struct commit *commit) + struct commit *commit, + struct prio_queue *queue) { if (!ent->bitmap) ent->bitmap = bitmap_new(); - /* - * mark ourselves, but do not bother with parents; their values - * will already have been propagated to us - */ bitmap_set(ent->bitmap, find_object_pos(&commit->object.oid)); - fill_bitmap_tree(ent->bitmap, get_commit_tree(commit)); + prio_queue_put(queue, commit); + + while (queue->nr) { + struct commit_list *p; + struct commit *c = prio_queue_get(queue); + + bitmap_set(ent->bitmap, find_object_pos(&c->object.oid)); + fill_bitmap_tree(ent->bitmap, get_commit_tree(c)); + + for (p = c->parents; p; p = p->next) { + int pos = find_object_pos(&p->item->object.oid); + if (!bitmap_get(ent->bitmap, pos)) { + bitmap_set(ent->bitmap, pos); + prio_queue_put(queue, p->item); + } + } + } } static void store_selected(struct bb_commit *ent, struct commit *commit) @@ -319,6 +333,7 @@ void bitmap_writer_build(struct packing_data *to_pack) struct bitmap_builder bb; size_t i; int nr_stored = 0; /* for progress */ + struct prio_queue queue = { compare_commits_by_gen_then_commit_date }; writer.bitmaps = kh_init_oid_map(); writer.to_pack = to_pack; @@ -335,7 +350,7 @@ void bitmap_writer_build(struct packing_data *to_pack) struct commit *child; int reused = 0; - fill_bitmap_commit(ent, commit); + fill_bitmap_commit(ent, commit, &queue); if (ent->selected) { store_selected(ent, commit); @@ -360,6 +375,7 @@ void bitmap_writer_build(struct packing_data *to_pack) bitmap_free(ent->bitmap); ent->bitmap = NULL; } + clear_prio_queue(&queue); bitmap_builder_clear(&bb); trace2_region_leave("pack-bitmap-write", "building_bitmaps_total", -- cgit v1.2.3