[PATCH 02/13] pack-revindex: prepare for incremental MIDX bitmaps
From: Taylor Blau <hidden>
Date: 2024-08-15 21:01:27
Subsystem:
the rest · Maintainer:
Linus Torvalds
Prepare the reverse index machinery to handle object lookups in an
incremental MIDX bitmap. These changes are broken out across a few
functions:
- load_midx_revindex() learns to use the appropriate MIDX filename
depending on whether the given 'struct multi_pack_index *' is
incremental or not.
- pack_pos_to_midx() and midx_to_pack_pos() now both take in a global
object position in the MIDX pseudo-pack order, and finds the
earliest containing MIDX (similar to midx.c::midx_for_object().
- midx_pack_order_cmp() adjusts its call to pack_pos_to_midx() by the
number of objects in the base (since 'vb - midx->revindx_data' is
relative to the containing MIDX, and pack_pos_to_midx() expects a
global position).
Likewise, this function adjusts its output by adding
m->num_objects_in_base to return a global position out through the
`*pos` pointer.
Together, these changes are sufficient to use the multi-pack index's
reverse index format for incremental multi-pack reachability bitmaps.
Signed-off-by: Taylor Blau <redacted>
---
pack-bitmap.c | 30 ++++++++++++++++++++----------
pack-revindex.c | 32 +++++++++++++++++++++++---------
2 files changed, 43 insertions(+), 19 deletions(-)
diff --git a/pack-bitmap.c b/pack-bitmap.c
index 2e657a2aa4..0a7039d955 100644
--- a/pack-bitmap.c
+++ b/pack-bitmap.c@@ -170,6 +170,15 @@ static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index) return read_bitmap(index->map, index->map_size, &index->map_pos); } +static uint32_t bitmap_non_extended_bits(struct bitmap_index *index) +{ + if (index->midx) { + struct multi_pack_index *m = index->midx; + return m->num_objects + m->num_objects_in_base; + } + return index->pack->num_objects; +} + static uint32_t bitmap_num_objects(struct bitmap_index *index) { if (index->midx)
@@ -925,7 +934,7 @@ static inline int bitmap_position_extended(struct bitmap_index *bitmap_git, if (pos < kh_end(positions)) { int bitmap_pos = kh_value(positions, pos); - return bitmap_pos + bitmap_num_objects(bitmap_git); + return bitmap_pos + bitmap_non_extended_bits(bitmap_git); } return -1;
@@ -993,7 +1002,7 @@ static int ext_index_add_object(struct bitmap_index *bitmap_git, bitmap_pos = kh_value(eindex->positions, hash_pos); } - return bitmap_pos + bitmap_num_objects(bitmap_git); + return bitmap_pos + bitmap_non_extended_bits(bitmap_git); } struct bitmap_show_data {
@@ -1498,7 +1507,8 @@ static void show_extended_objects(struct bitmap_index *bitmap_git, for (i = 0; i < eindex->count; ++i) { struct object *obj; - if (!bitmap_get(objects, st_add(bitmap_num_objects(bitmap_git), i))) + if (!bitmap_get(objects, + st_add(bitmap_non_extended_bits(bitmap_git), i))) continue; obj = eindex->objects[i];
@@ -1677,7 +1687,7 @@ static void filter_bitmap_exclude_type(struct bitmap_index *bitmap_git, * them individually. */ for (i = 0; i < eindex->count; i++) { - size_t pos = st_add(i, bitmap_num_objects(bitmap_git)); + size_t pos = st_add(i, bitmap_non_extended_bits(bitmap_git)); if (eindex->objects[i]->type == type && bitmap_get(to_filter, pos) && !bitmap_get(tips, pos))
@@ -1703,7 +1713,7 @@ static unsigned long get_size_by_pos(struct bitmap_index *bitmap_git, oi.sizep = &size; - if (pos < bitmap_num_objects(bitmap_git)) { + if (pos < bitmap_non_extended_bits(bitmap_git)) { struct packed_git *pack; off_t ofs;
@@ -1726,7 +1736,7 @@ static unsigned long get_size_by_pos(struct bitmap_index *bitmap_git, } } else { struct eindex *eindex = &bitmap_git->ext_index; - struct object *obj = eindex->objects[pos - bitmap_num_objects(bitmap_git)]; + struct object *obj = eindex->objects[pos - bitmap_non_extended_bits(bitmap_git)]; if (oid_object_info_extended(the_repository, &obj->oid, &oi, 0) < 0) die(_("unable to get size of %s"), oid_to_hex(&obj->oid)); }
@@ -1878,7 +1888,7 @@ static void filter_packed_objects_from_bitmap(struct bitmap_index *bitmap_git, uint32_t objects_nr; size_t i, pos; - objects_nr = bitmap_num_objects(bitmap_git); + objects_nr = bitmap_non_extended_bits(bitmap_git); pos = objects_nr / BITS_IN_EWORD; if (pos > result->word_alloc)
@@ -2399,7 +2409,7 @@ static uint32_t count_object_type(struct bitmap_index *bitmap_git, for (i = 0; i < eindex->count; ++i) { if (eindex->objects[i]->type == type && bitmap_get(objects, - st_add(bitmap_num_objects(bitmap_git), i))) + st_add(bitmap_non_extended_bits(bitmap_git), i))) count++; }
@@ -2798,7 +2808,7 @@ uint32_t *create_bitmap_mapping(struct bitmap_index *bitmap_git, BUG("rebuild_existing_bitmaps: missing required rev-cache " "extension"); - num_objects = bitmap_num_objects(bitmap_git); + num_objects = bitmap_non_extended_bits(bitmap_git); CALLOC_ARRAY(reposition, num_objects); for (i = 0; i < num_objects; ++i) {
@@ -2941,7 +2951,7 @@ static off_t get_disk_usage_for_extended(struct bitmap_index *bitmap_git) struct object *obj = eindex->objects[i]; if (!bitmap_get(result, - st_add(bitmap_num_objects(bitmap_git), i))) + st_add(bitmap_non_extended_bits(bitmap_git), i))) continue; if (oid_object_info_extended(the_repository, &obj->oid, &oi, 0) < 0)
diff --git a/pack-revindex.c b/pack-revindex.c
index 22d3c23464..ce3f7ae214 100644
--- a/pack-revindex.c
+++ b/pack-revindex.c@@ -383,8 +383,12 @@ int load_midx_revindex(struct multi_pack_index *m) trace2_data_string("load_midx_revindex", the_repository, "source", "rev"); - get_midx_filename_ext(&revindex_name, m->object_dir, - get_midx_checksum(m), MIDX_EXT_REV); + if (m->has_chain) + get_split_midx_filename_ext(&revindex_name, m->object_dir, + get_midx_checksum(m), MIDX_EXT_REV); + else + get_midx_filename_ext(&revindex_name, m->object_dir, + get_midx_checksum(m), MIDX_EXT_REV); ret = load_revindex_from_disk(revindex_name.buf, m->num_objects,
@@ -471,11 +475,15 @@ off_t pack_pos_to_offset(struct packed_git *p, uint32_t pos) uint32_t pack_pos_to_midx(struct multi_pack_index *m, uint32_t pos) { + while (m && pos < m->num_objects_in_base) + m = m->base_midx; + if (!m) + BUG("NULL multi-pack-index for object position: %"PRIu32, pos); if (!m->revindex_data) BUG("pack_pos_to_midx: reverse index not yet loaded"); - if (m->num_objects <= pos) + if (m->num_objects + m->num_objects_in_base <= pos) BUG("pack_pos_to_midx: out-of-bounds object at %"PRIu32, pos); - return get_be32(m->revindex_data + pos); + return get_be32(m->revindex_data + pos - m->num_objects_in_base); } struct midx_pack_key {
@@ -491,7 +499,8 @@ static int midx_pack_order_cmp(const void *va, const void *vb) const struct midx_pack_key *key = va; struct multi_pack_index *midx = key->midx; - uint32_t versus = pack_pos_to_midx(midx, (uint32_t*)vb - (const uint32_t *)midx->revindex_data); + size_t pos = (uint32_t*)vb - (const uint32_t *)midx->revindex_data; + uint32_t versus = pack_pos_to_midx(midx, pos + midx->num_objects_in_base); uint32_t versus_pack = nth_midxed_pack_int_id(midx, versus); off_t versus_offset;
@@ -529,9 +538,9 @@ static int midx_key_to_pack_pos(struct multi_pack_index *m, { uint32_t *found; - if (key->pack >= m->num_packs) + if (key->pack >= m->num_packs + m->num_packs_in_base) BUG("MIDX pack lookup out of bounds (%"PRIu32" >= %"PRIu32")", - key->pack, m->num_packs); + key->pack, m->num_packs + m->num_packs_in_base); /* * The preferred pack sorts first, so determine its identifier by * looking at the first object in pseudo-pack order.
@@ -551,7 +560,8 @@ static int midx_key_to_pack_pos(struct multi_pack_index *m, if (!found) return -1; - *pos = found - m->revindex_data; + *pos = (found - m->revindex_data) + m->num_objects_in_base; + return 0; }
@@ -559,9 +569,13 @@ int midx_to_pack_pos(struct multi_pack_index *m, uint32_t at, uint32_t *pos) { struct midx_pack_key key; + while (m && at < m->num_objects_in_base) + m = m->base_midx; + if (!m) + BUG("NULL multi-pack-index for object position: %"PRIu32, at); if (!m->revindex_data) BUG("midx_to_pack_pos: reverse index not yet loaded"); - if (m->num_objects <= at) + if (m->num_objects + m->num_objects_in_base <= at) BUG("midx_to_pack_pos: out-of-bounds object at %"PRIu32, at); key.pack = nth_midxed_pack_int_id(m, at);
--
2.46.0.86.ge766d390f0.dirty