diff options
| -rw-r--r-- | pack-bitmap-write.c | 72 | ||||
| -rwxr-xr-x | t/t5310-pack-bitmaps.sh | 85 |
2 files changed, 148 insertions, 9 deletions
diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c index 7e218d02a6..0af93193d8 100644 --- a/pack-bitmap-write.c +++ b/pack-bitmap-write.c @@ -180,8 +180,10 @@ static void compute_xor_offsets(void) struct bb_commit { struct commit_list *reverse_edges; + struct bitmap *commit_mask; struct bitmap *bitmap; - unsigned selected:1; + unsigned selected:1, + maximal:1; unsigned idx; /* within selected array */ }; @@ -198,7 +200,7 @@ static void bitmap_builder_init(struct bitmap_builder *bb, { struct rev_info revs; struct commit *commit; - unsigned int i; + unsigned int i, num_maximal; memset(bb, 0, sizeof(*bb)); init_bb_data(&bb->data); @@ -210,27 +212,85 @@ static void bitmap_builder_init(struct bitmap_builder *bb, for (i = 0; i < writer->selected_nr; i++) { struct commit *c = writer->selected[i].commit; struct bb_commit *ent = bb_data_at(&bb->data, c); + ent->selected = 1; + ent->maximal = 1; ent->idx = i; + + ent->commit_mask = bitmap_new(); + bitmap_set(ent->commit_mask, i); + add_pending_object(&revs, &c->object, ""); } + num_maximal = writer->selected_nr; if (prepare_revision_walk(&revs)) die("revision walk setup failed"); while ((commit = get_revision(&revs))) { struct commit_list *p; + struct bb_commit *c_ent; parse_commit_or_die(commit); - ALLOC_GROW(bb->commits, bb->commits_nr + 1, bb->commits_alloc); - bb->commits[bb->commits_nr++] = commit; + c_ent = bb_data_at(&bb->data, commit); + + if (c_ent->maximal) { + if (!c_ent->selected) { + bitmap_set(c_ent->commit_mask, num_maximal); + num_maximal++; + } + + ALLOC_GROW(bb->commits, bb->commits_nr + 1, bb->commits_alloc); + bb->commits[bb->commits_nr++] = commit; + } for (p = commit->parents; p; p = p->next) { - struct bb_commit *ent = bb_data_at(&bb->data, p->item); - commit_list_insert(commit, &ent->reverse_edges); + struct bb_commit *p_ent = bb_data_at(&bb->data, p->item); + int c_not_p, p_not_c; + + if (!p_ent->commit_mask) { + p_ent->commit_mask = bitmap_new(); + c_not_p = 1; + p_not_c = 0; + } else { + c_not_p = bitmap_is_subset(c_ent->commit_mask, p_ent->commit_mask); + p_not_c = bitmap_is_subset(p_ent->commit_mask, c_ent->commit_mask); + } + + if (!c_not_p) + continue; + + bitmap_or(p_ent->commit_mask, c_ent->commit_mask); + + if (p_not_c) + p_ent->maximal = 1; + else { + p_ent->maximal = 0; + free_commit_list(p_ent->reverse_edges); + p_ent->reverse_edges = NULL; + } + + if (c_ent->maximal) { + commit_list_insert(commit, &p_ent->reverse_edges); + } else { + struct commit_list *cc = c_ent->reverse_edges; + + for (; cc; cc = cc->next) { + if (!commit_list_contains(cc->item, p_ent->reverse_edges)) + commit_list_insert(cc->item, &p_ent->reverse_edges); + } + } } + + bitmap_free(c_ent->commit_mask); + c_ent->commit_mask = NULL; } + + trace2_data_intmax("pack-bitmap-write", the_repository, + "num_selected_commits", writer->selected_nr); + trace2_data_intmax("pack-bitmap-write", the_repository, + "num_maximal_commits", num_maximal); } static void bitmap_builder_clear(struct bitmap_builder *bb) diff --git a/t/t5310-pack-bitmaps.sh b/t/t5310-pack-bitmaps.sh index 1dd9723721..7ba796b2c3 100755 --- a/t/t5310-pack-bitmaps.sh +++ b/t/t5310-pack-bitmaps.sh @@ -20,12 +20,88 @@ has_any () { grep -Ff "$1" "$2" } +# To ensure the logic for "maximal commits" is exercised, make +# the repository a bit more complicated. +# +# other master +# * * +# (99 commits) (99 commits) +# * * +# |\ /| +# | * octo-other octo-master * | +# |/|\_________ ____________/|\| +# | \ \/ __________/ | +# | | ________/\ / | +# * |/ * merge-right * +# | _|__________/ \____________ | +# |/ | \| +# (l1) * * merge-left * (r1) +# | / \________________________ | +# |/ \| +# (l2) * * (r2) +# \___________________________ | +# \| +# * (base) +# +# The important part for the maximal commit algorithm is how +# the bitmasks are extended. Assuming starting bit positions +# for master (bit 0) and other (bit 1), and some flexibility +# in the order that merge bases are visited, the bitmasks at +# the end should be: +# +# master: 1 (maximal, selected) +# other: 01 (maximal, selected) +# octo-master: 1 +# octo-other: 01 +# merge-right: 111 (maximal) +# (l1): 111 +# (r1): 111 +# merge-left: 1101 (maximal) +# (l2): 11111 (maximal) +# (r2): 111101 (maximal) +# (base): 1111111 (maximal) + test_expect_success 'setup repo with moderate-sized history' ' - test_commit_bulk --id=file 100 && + test_commit_bulk --id=file 10 && git branch -M second && git checkout -b other HEAD~5 && test_commit_bulk --id=side 10 && + + # add complicated history setup, including merges and + # ambiguous merge-bases + + git checkout -b merge-left other~2 && + git merge second~2 -m "merge-left" && + + git checkout -b merge-right second~1 && + git merge other~1 -m "merge-right" && + + git checkout -b octo-second second && + git merge merge-left merge-right -m "octopus-second" && + + git checkout -b octo-other other && + git merge merge-left merge-right -m "octopus-other" && + + git checkout other && + git merge octo-other -m "pull octopus" && + + git checkout second && + git merge octo-second -m "pull octopus" && + + # Remove these branches so they are not selected + # as bitmap tips + git branch -D merge-left && + git branch -D merge-right && + git branch -D octo-other && + git branch -D octo-second && + + # add padding to make these merges less interesting + # and avoid having them selected for bitmaps + test_commit_bulk --id=file 100 && + git checkout other && + test_commit_bulk --id=side 100 && git checkout second && + bitmaptip=$(git rev-parse second) && blob=$(echo tagged-blob | git hash-object -w --stdin) && git tag tagged-blob $blob && @@ -33,9 +109,12 @@ test_expect_success 'setup repo with moderate-sized history' ' ' test_expect_success 'full repack creates bitmaps' ' - git repack -ad && + GIT_TRACE2_EVENT_NESTING=4 GIT_TRACE2_EVENT="$(pwd)/trace" \ + git repack -ad && ls .git/objects/pack/ | grep bitmap >output && - test_line_count = 1 output + test_line_count = 1 output && + grep "\"key\":\"num_selected_commits\",\"value\":\"106\"" trace && + grep "\"key\":\"num_maximal_commits\",\"value\":\"111\"" trace ' test_expect_success 'rev-list --test-bitmap verifies bitmaps' ' |