[PATCH v5 13/17] commit-graph.c: unconditionally load Bloom filters

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



In an earlier commit, we began ignoring the Bloom data ("BDAT") chunk
for commit-graphs whose Bloom filters were computed using a hash version
  incompatible with the value of `commitGraph.changedPathVersion`.

Now that the Bloom API has been hardened to discard these incompatible
filters (with the exception of low-level APIs), we can safely load these
Bloom filters unconditionally.

We no longer want to return early from `graph_read_bloom_data()`, and
similarly do not want to set the bloom_settings' `hash_version` field as
a side-effect. The latter is because we want to wait until we know which
Bloom settings we're using (either the defaults, from the GIT_TEST
variables, or from the previous commit-graph layer) before deciding what
hash_version to use.

If we detect an existing BDAT chunk, we'll infer the rest of the
settings (e.g., number of hashes, bits per entry, and maximum number of
changed paths) from the earlier graph layer. The hash_version will be
inferred from the previous layer as well, unless one has already been
specified via configuration.

Once all of that is done, we normalize the value of the hash_version to
either "1" or "2".

Signed-off-by: Taylor Blau <me@xxxxxxxxxxxx>
---
 commit-graph.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/commit-graph.c b/commit-graph.c
index 22237e7dfc..a2063d5f91 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -362,11 +362,6 @@ static int graph_read_bloom_data(const unsigned char *chunk_start,
 
 	hash_version = get_be32(chunk_start);
 
-	if (*c->commit_graph_changed_paths_version == -1)
-		*c->commit_graph_changed_paths_version = hash_version;
-	else if (hash_version != *c->commit_graph_changed_paths_version)
-		return 0;
-
 	g->chunk_bloom_data = chunk_start;
 	g->chunk_bloom_data_size = chunk_size;
 	g->bloom_filter_settings = xmalloc(sizeof(struct bloom_filter_settings));
@@ -2532,8 +2527,7 @@ int write_commit_graph(struct object_directory *odb,
 	ctx->write_generation_data = (get_configured_generation_version(r) == 2);
 	ctx->num_generation_data_overflows = 0;
 
-	bloom_settings.hash_version = r->settings.commit_graph_changed_paths_version == 2
-		? 2 : 1;
+	bloom_settings.hash_version = r->settings.commit_graph_changed_paths_version;
 	bloom_settings.bits_per_entry = git_env_ulong("GIT_TEST_BLOOM_SETTINGS_BITS_PER_ENTRY",
 						      bloom_settings.bits_per_entry);
 	bloom_settings.num_hashes = git_env_ulong("GIT_TEST_BLOOM_SETTINGS_NUM_HASHES",
@@ -2565,10 +2559,18 @@ int write_commit_graph(struct object_directory *odb,
 		/* We have changed-paths already. Keep them in the next graph */
 		if (g && g->bloom_filter_settings) {
 			ctx->changed_paths = 1;
-			ctx->bloom_settings = g->bloom_filter_settings;
+
+			/* don't propagate the hash_version unless unspecified */
+			if (bloom_settings.hash_version == -1)
+				bloom_settings.hash_version = g->bloom_filter_settings->hash_version;
+			bloom_settings.bits_per_entry = g->bloom_filter_settings->bits_per_entry;
+			bloom_settings.num_hashes = g->bloom_filter_settings->num_hashes;
+			bloom_settings.max_changed_paths = g->bloom_filter_settings->max_changed_paths;
 		}
 	}
 
+	bloom_settings.hash_version = bloom_settings.hash_version == 2 ? 2 : 1;
+
 	if (ctx->split) {
 		struct commit_graph *g = ctx->r->objects->commit_graph;
 
-- 
2.43.0.334.gd4dbce1db5.dirty





[Index of Archives]     [Linux Kernel Development]     [Gcc Help]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [V4L]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]     [Fedora Users]

  Powered by Linux