On Wed, Aug 05, 2020 at 02:01:29PM -0700, Junio C Hamano wrote:
> Taylor Blau <me@xxxxxxxxxxxx> writes:
>
> > @@ -71,6 +72,10 @@ struct commit_graph {
> > const unsigned char *chunk_base_graphs;
> > const unsigned char *chunk_bloom_indexes;
> > const unsigned char *chunk_bloom_data;
> > + const unsigned char *chunk_bloom_large_filters;
> > +
> > + size_t bloom_large_to_alloc;
> > + struct bitmap bloom_large;
>
> Hmph, is the API rich enough to allow users to release the resource
> used by such an embedded bitmap? I ask becuase...
>
> > @@ -2503,6 +2577,7 @@ void free_commit_graph(struct commit_graph *g)
> > }
> > free(g->filename);
> > free(g->bloom_filter_settings);
> > + bitmap_free(g->bloom_large);
> > free(g);
> > }
>
> ... this hunk cannot be possibly correct as-is, and cannot be made
> correct without changing g->bloom_large to a pointer into a heap
> allocated bitmap, because bitmap_free() wants to not just release
> the resource held by the bitmap but the bitmap itself.
Yuck, that's definitely wrong. Serves me right for sneaking this in
after I had run `git rebase -x 'make -j40 DEVELOPER=1 test'
upstream/master` ;-).
Below the scissors line should do the trick. It should apply cleanly at
this point in the series, but it'll produce a compilation failure on the
very last patch (fixing it is straightforward and looks like the
following diff):
diff --git a/bloom.c b/bloom.c
index d0c0fd049d..8d07209c6b 100644
--- a/bloom.c
+++ b/bloom.c
@@ -52,7 +52,7 @@ static int load_bloom_filter_from_graph(struct commit_graph *g,
start_index = 0;
if ((start_index == end_index) &&
- (g->bloom_large.word_alloc && !bitmap_get(&g->bloom_large, lex_pos))) {
+ (g->bloom_large && !bitmap_get(g->bloom_large, lex_pos))) {
/*
* If the filter is zero-length, either (1) the filter has no
* changes, (2) the filter has too many changes, or (3) it
In either case, this will fix the bad free():
--- >8 ---
Subject: [PATCH] fixup! commit-graph: add large-filters bitmap chunk
Signed-off-by: Taylor Blau <me@xxxxxxxxxxxx>
---
commit-graph.c | 18 ++++++++++--------
commit-graph.h | 2 +-
2 files changed, 11 insertions(+), 9 deletions(-)
diff --git a/commit-graph.c b/commit-graph.c
index 1fee49d171..add76f1824 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -438,7 +438,10 @@ struct commit_graph *parse_commit_graph(struct repository *r,
graph->bloom_large_to_alloc = get_be64(chunk_lookup + 4)
- chunk_offset - sizeof(uint32_t);
- graph->bloom_large.word_alloc = 0; /* populate when necessary */
+ /*
+ * leave 'bloom_large' uninitialized, and
+ * populate when necessary
+ */
graph->chunk_bloom_large_filters = data + chunk_offset + sizeof(uint32_t);
graph->bloom_filter_settings->max_changed_paths = get_be32(data + chunk_offset);
}
@@ -960,17 +963,15 @@ static int get_bloom_filter_large_in_graph(struct commit_graph *g,
if (!g || !g->bloom_large_to_alloc)
return 0;
- if (!g->bloom_large.word_alloc) {
+ if (!g->bloom_large) {
size_t i;
- g->bloom_large.word_alloc = g->bloom_large_to_alloc;
- g->bloom_large.words = xmalloc(g->bloom_large_to_alloc * sizeof(eword_t));
-
+ g->bloom_large = bitmap_word_alloc(g->bloom_large_to_alloc);
for (i = 0; i < g->bloom_large_to_alloc; i++)
- g->bloom_large.words[i] = get_be64(g->chunk_bloom_large_filters
- + i * sizeof(eword_t));
+ g->bloom_large->words[i] = get_be64(g->chunk_bloom_large_filters
+ + i * sizeof(eword_t));
}
- return bitmap_get(&g->bloom_large, graph_pos - g->num_commits_in_base);
+ return bitmap_get(g->bloom_large, graph_pos - g->num_commits_in_base);
}
struct packed_oid_list {
@@ -2360,6 +2361,7 @@ int write_commit_graph(struct object_directory *odb,
free(ctx->graph_name);
free(ctx->commits.list);
free(ctx->oids.list);
+ free(ctx->bloom_large);
if (ctx->commit_graph_filenames_after) {
for (i = 0; i < ctx->num_commit_graphs_after; i++) {
diff --git a/commit-graph.h b/commit-graph.h
index f4fb996dd5..b1ab86a3c8 100644
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -75,7 +75,7 @@ struct commit_graph {
const unsigned char *chunk_bloom_large_filters;
size_t bloom_large_to_alloc;
- struct bitmap bloom_large;
+ struct bitmap *bloom_large;
struct bloom_filter_settings *bloom_filter_settings;
};
--
2.28.0.rc1.13.ge78abce653
