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Szeder's commit-graph cleanups #650

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af84c25
tree-walk.c: don't match submodule entries for 'submod/anything'
szeder Jun 4, 2020
1e1671e
commit-graph: fix parsing the Chunk Lookup table
szeder May 29, 2020
a09d0bd
commit-graph-format.txt: all multi-byte numbers are in network byte o…
szeder May 29, 2020
32a6f11
commit-slab: add a function to deep free entries on the slab
szeder May 29, 2020
1a70ff0
diff.h: drop diff_tree_oid() & friends' return value
szeder Jun 4, 2020
636c206
commit-graph: clean up #includes
szeder Jun 4, 2020
cd9e033
commit-graph: simplify parse_commit_graph() #1
szeder May 29, 2020
83641b5
commit-graph: simplify parse_commit_graph() #2
szeder Jun 4, 2020
9b818b9
commit-graph: simplify write_commit_graph_file() #1
szeder Jun 4, 2020
5984fb0
commit-graph: simplify write_commit_graph_file() #2
szeder May 29, 2020
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2 changes: 1 addition & 1 deletion Documentation/technical/commit-graph-format.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -32,7 +32,7 @@ the body into "chunks" and provide a binary lookup table at the beginning
of the body. The header includes certain values, such as number of chunks
and hash type.

All 4-byte numbers are in network order.
All multi-byte numbers are in network byte order.

HEADER:

Expand Down
113 changes: 48 additions & 65 deletions commit-graph.c
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Original file line number Diff line number Diff line change
@@ -1,7 +1,5 @@
#include "cache.h"
#include "config.h"
#include "dir.h"
#include "git-compat-util.h"
#include "config.h"
#include "lockfile.h"
#include "pack.h"
#include "packfile.h"
Expand Down Expand Up @@ -232,8 +230,7 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
const unsigned char *data, *chunk_lookup;
uint32_t i;
struct commit_graph *graph;
uint64_t last_chunk_offset;
uint32_t last_chunk_id;
uint64_t next_chunk_offset;
uint32_t graph_signature;
unsigned char graph_version, hash_version;

Expand Down Expand Up @@ -274,25 +271,26 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
graph->data = graph_map;
graph->data_len = graph_size;

last_chunk_id = 0;
last_chunk_offset = 8;
if (graph_size < GRAPH_HEADER_SIZE +
(graph->num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH +
GRAPH_FANOUT_SIZE + the_hash_algo->rawsz) {
error(_("commit-graph file is too small to hold %u chunks"),
graph->num_chunks);
free(graph);
return NULL;
}

chunk_lookup = data + 8;
next_chunk_offset = get_be64(chunk_lookup + 4);
for (i = 0; i < graph->num_chunks; i++) {
uint32_t chunk_id;
uint64_t chunk_offset;
uint64_t chunk_offset = next_chunk_offset;
int chunk_repeated = 0;

if (data + graph_size - chunk_lookup <
GRAPH_CHUNKLOOKUP_WIDTH) {
error(_("commit-graph chunk lookup table entry missing; file may be incomplete"));
free(graph);
return NULL;
}

chunk_id = get_be32(chunk_lookup + 0);
chunk_offset = get_be64(chunk_lookup + 4);

chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
next_chunk_offset = get_be64(chunk_lookup + 4);

if (chunk_offset > graph_size - the_hash_algo->rawsz) {
error(_("commit-graph improper chunk offset %08x%08x"), (uint32_t)(chunk_offset >> 32),
Expand All @@ -312,8 +310,11 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
case GRAPH_CHUNKID_OIDLOOKUP:
if (graph->chunk_oid_lookup)
chunk_repeated = 1;
else
else {
graph->chunk_oid_lookup = data + chunk_offset;
graph->num_commits = (next_chunk_offset - chunk_offset)
/ graph->hash_len;
}
break;

case GRAPH_CHUNKID_DATA:
Expand Down Expand Up @@ -368,15 +369,6 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
free(graph);
return NULL;
}

if (last_chunk_id == GRAPH_CHUNKID_OIDLOOKUP)
{
graph->num_commits = (chunk_offset - last_chunk_offset)
/ graph->hash_len;
}

last_chunk_id = chunk_id;
last_chunk_offset = chunk_offset;
}

if (graph->chunk_bloom_indexes && graph->chunk_bloom_data) {
Expand Down Expand Up @@ -1530,17 +1522,22 @@ static int write_graph_chunk_base(struct hashfile *f,
return 0;
}

struct chunk_info {
uint32_t id;
uint64_t size;
};

static int write_commit_graph_file(struct write_commit_graph_context *ctx)
{
uint32_t i;
int fd;
struct hashfile *f;
struct lock_file lk = LOCK_INIT;
uint32_t chunk_ids[MAX_NUM_CHUNKS + 1];
uint64_t chunk_offsets[MAX_NUM_CHUNKS + 1];
struct chunk_info chunks[MAX_NUM_CHUNKS + 1];
const unsigned hashsz = the_hash_algo->rawsz;
struct strbuf progress_title = STRBUF_INIT;
int num_chunks = 3;
uint64_t chunk_offset;
struct object_id file_hash;
const struct bloom_filter_settings bloom_settings = DEFAULT_BLOOM_FILTER_SETTINGS;

Expand Down Expand Up @@ -1580,51 +1577,34 @@ static int write_commit_graph_file(struct write_commit_graph_context *ctx)
f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
}

chunk_ids[0] = GRAPH_CHUNKID_OIDFANOUT;
chunk_ids[1] = GRAPH_CHUNKID_OIDLOOKUP;
chunk_ids[2] = GRAPH_CHUNKID_DATA;
chunks[0].id = GRAPH_CHUNKID_OIDFANOUT;
chunks[0].size = GRAPH_FANOUT_SIZE;
chunks[1].id = GRAPH_CHUNKID_OIDLOOKUP;
chunks[1].size = hashsz * ctx->commits.nr;
chunks[2].id = GRAPH_CHUNKID_DATA;
chunks[2].size = (hashsz + 16) * ctx->commits.nr;
if (ctx->num_extra_edges) {
chunk_ids[num_chunks] = GRAPH_CHUNKID_EXTRAEDGES;
chunks[num_chunks].id = GRAPH_CHUNKID_EXTRAEDGES;
chunks[num_chunks].size = 4 * ctx->num_extra_edges;
num_chunks++;
}
if (ctx->changed_paths) {
chunk_ids[num_chunks] = GRAPH_CHUNKID_BLOOMINDEXES;
chunks[num_chunks].id = GRAPH_CHUNKID_BLOOMINDEXES;
chunks[num_chunks].size = sizeof(uint32_t) * ctx->commits.nr;
num_chunks++;
chunk_ids[num_chunks] = GRAPH_CHUNKID_BLOOMDATA;
chunks[num_chunks].id = GRAPH_CHUNKID_BLOOMDATA;
chunks[num_chunks].size = sizeof(uint32_t) * 3
+ ctx->total_bloom_filter_data_size;
num_chunks++;
}
if (ctx->num_commit_graphs_after > 1) {
chunk_ids[num_chunks] = GRAPH_CHUNKID_BASE;
num_chunks++;
}

chunk_ids[num_chunks] = 0;

chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
chunk_offsets[2] = chunk_offsets[1] + hashsz * ctx->commits.nr;
chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * ctx->commits.nr;

num_chunks = 3;
if (ctx->num_extra_edges) {
chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
4 * ctx->num_extra_edges;
chunks[num_chunks].id = GRAPH_CHUNKID_BASE;
chunks[num_chunks].size = hashsz * (ctx->num_commit_graphs_after - 1);
num_chunks++;
}
if (ctx->changed_paths) {
chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
sizeof(uint32_t) * ctx->commits.nr;
num_chunks++;

chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
sizeof(uint32_t) * 3 + ctx->total_bloom_filter_data_size;
num_chunks++;
}
if (ctx->num_commit_graphs_after > 1) {
chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
hashsz * (ctx->num_commit_graphs_after - 1);
num_chunks++;
}
chunks[num_chunks].id = 0;
chunks[num_chunks].size = 0;

hashwrite_be32(f, GRAPH_SIGNATURE);

Expand All @@ -1633,13 +1613,16 @@ static int write_commit_graph_file(struct write_commit_graph_context *ctx)
hashwrite_u8(f, num_chunks);
hashwrite_u8(f, ctx->num_commit_graphs_after - 1);

chunk_offset = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
for (i = 0; i <= num_chunks; i++) {
uint32_t chunk_write[3];

chunk_write[0] = htonl(chunk_ids[i]);
chunk_write[1] = htonl(chunk_offsets[i] >> 32);
chunk_write[2] = htonl(chunk_offsets[i] & 0xffffffff);
chunk_write[0] = htonl(chunks[i].id);
chunk_write[1] = htonl(chunk_offset >> 32);
chunk_write[2] = htonl(chunk_offset & 0xffffffff);
hashwrite(f, chunk_write, 12);

chunk_offset += chunks[i].size;
}

if (ctx->report_progress) {
Expand Down
6 changes: 3 additions & 3 deletions commit-graph.h
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Original file line number Diff line number Diff line change
Expand Up @@ -2,9 +2,6 @@
#define COMMIT_GRAPH_H

#include "git-compat-util.h"
#include "repository.h"
#include "string-list.h"
#include "cache.h"
#include "object-store.h"

#define GIT_TEST_COMMIT_GRAPH "GIT_TEST_COMMIT_GRAPH"
Expand All @@ -22,6 +19,9 @@ void git_test_write_commit_graph_or_die(void);

struct commit;
struct bloom_filter_settings;
struct repository;
struct raw_object_store;
struct string_list;

char *get_commit_graph_filename(struct object_directory *odb);
int open_commit_graph(const char *graph_file, int *fd, struct stat *st);
Expand Down
1 change: 1 addition & 0 deletions commit-slab-decl.h
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Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,7 @@ struct slabname { \
void init_ ##slabname## _with_stride(struct slabname *s, unsigned stride); \
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On the Git mailing list, René Scharfe wrote (reply to this):

Am 05.06.20 um 15:00 schrieb SZEDER Gábor via GitGitGadget:
> From: =?UTF-8?q?SZEDER=20G=C3=A1bor?= <[email protected]>
>
> clear_##slabname() frees only the memory allocated for a commit slab
> itself, but entries in the commit slab might own additional memory
> outside the slab that should be freed as well.  We already have (at
> least) one such commit slab, and this patch series is about to add one
> more.
>
> To free all additional memory owned by entries on the commit slab the
> user of such a slab could iterate over all commits it knows about,
> peek whether there is a valid entry associated with each commit, and
> free the additional memory, if any.  Or it could rely on intimate
> knowledge about the internals of the commit slab implementation, and
> could itself iterate directly through all entries in the slab, and
> free the additional memory.  Or it could just leak the additional
> memory...
>
> Introduce deep_clear_##slabname() to allow releasing memory owned by
> commit slab entries by invoking the 'void free_fn(elemtype *ptr)'
> function specified as parameter for each entry in the slab.

Adding a new function instead of extending the existing ones makes
sense, as this is a rare requirement.

>
> Use it in get_shallow_commits() in 'shallow.c' to replace an
> open-coded iteration over a commit slab's entries.
>
> Signed-off-by: SZEDER Gábor <[email protected]>
> Signed-off-by: Derrick Stolee <[email protected]>
> ---
>  commit-slab-decl.h |  1 +
>  commit-slab-impl.h | 13 +++++++++++++
>  commit-slab.h      | 10 ++++++++++
>  shallow.c          | 14 +++++---------
>  4 files changed, 29 insertions(+), 9 deletions(-)
>
> diff --git a/commit-slab-decl.h b/commit-slab-decl.h
> index adc7b46c83b..286164b7e27 100644
> --- a/commit-slab-decl.h
> +++ b/commit-slab-decl.h
> @@ -32,6 +32,7 @@ struct slabname {							\
>  void init_ ##slabname## _with_stride(struct slabname *s, unsigned stride); \
>  void init_ ##slabname(struct slabname *s);				\
>  void clear_ ##slabname(struct slabname *s);				\
> +void deep_clear_ ##slabname(struct slabname *s, void (*free_fn)(elemtype *ptr)); \
>  elemtype *slabname## _at_peek(struct slabname *s, const struct commit *c, int add_if_missing); \
>  elemtype *slabname## _at(struct slabname *s, const struct commit *c);	\
>  elemtype *slabname## _peek(struct slabname *s, const struct commit *c)
> diff --git a/commit-slab-impl.h b/commit-slab-impl.h
> index 5c0eb91a5d1..557738df271 100644
> --- a/commit-slab-impl.h
> +++ b/commit-slab-impl.h
> @@ -38,6 +38,19 @@ scope void clear_ ##slabname(struct slabname *s)			\
>  	FREE_AND_NULL(s->slab);						\
>  }									\
>  									\
> +scope void deep_clear_ ##slabname(struct slabname *s, void (*free_fn)(elemtype *)) \
> +{									\
> +	unsigned int i;							\
> +	for (i = 0; i < s->slab_count; i++) {				\
> +		unsigned int j;						\
> +		if (!s->slab[i])					\
> +			continue;					\
> +		for (j = 0; j < s->slab_size; j++)			\
> +			free_fn(&s->slab[i][j * s->stride]);		\
> +	}								\
> +	clear_ ##slabname(s);						> +}									\


Why pass an elemtype pointer to the callback function instead of
a plain elemtype?  Because it matches the return type of _at() and
_peek().  Consistency, good.  Handing it a pointer allows the
callback to pass it on to free(), though, which would be bad,
since we do that in clear_() as well.  Hmm.

> +									\
>  scope elemtype *slabname## _at_peek(struct slabname *s,			\
>  						  const struct commit *c, \
>  						  int add_if_missing)   \
> diff --git a/commit-slab.h b/commit-slab.h
> index 05b3f2804e7..8e72a305365 100644
> --- a/commit-slab.h
> +++ b/commit-slab.h
> @@ -47,6 +47,16 @@
>   *
>   *   Call this function before the slab falls out of scope to avoid
>   *   leaking memory.
> + *
> + * - void deep_clear_indegree(struct indegree *, void (*free_fn)(int*))
> + *
> + *   Empties the slab, similar to clear_indegree(), but in addition it
> + *   calls the given 'free_fn' for each slab entry to release any
> + *   additional memory that might be owned by the entry (but not the
> + *   entry itself!).
> + *   Note that 'free_fn' might be called even for entries for which no
> + *   indegree_at() call has been made; in this case 'free_fn' is invoked
> + *   with a pointer to a zero-initialized location.
>   */
>
>  #define define_commit_slab(slabname, elemtype) \
> diff --git a/shallow.c b/shallow.c
> index 7fd04afed19..c4ac8a73273 100644
> --- a/shallow.c
> +++ b/shallow.c
> @@ -84,6 +84,10 @@ int is_repository_shallow(struct repository *r)
>   * supports a "valid" flag.
>   */
>  define_commit_slab(commit_depth, int *);
> +static void free_depth_in_slab(int **ptr)
> +{
> +	FREE_AND_NULL(*ptr);
> +}

Why FREE_AND_NULL?  The original loop below called free().  The slabs
are all released by deep_clear_() immediately after the callbacks are
done anyway, so what's the point in zeroing these pointers?

>  struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
>  		int shallow_flag, int not_shallow_flag)
>  {
> @@ -150,15 +154,7 @@ struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
>  			}
>  		}
>  	}
> -	for (i = 0; i < depths.slab_count; i++) {
> -		int j;
> -
> -		if (!depths.slab[i])
> -			continue;
> -		for (j = 0; j < depths.slab_size; j++)
> -			free(depths.slab[i][j]);
> -	}
> -	clear_commit_depth(&depths);
> +	deep_clear_commit_depth(&depths, free_depth_in_slab);

What a relief!

>
>  	return result;
>  }
>

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On the Git mailing list, Derrick Stolee wrote (reply to this):

On 6/18/2020 4:59 PM, René Scharfe wrote:
> Am 05.06.20 um 15:00 schrieb SZEDER Gábor via GitGitGadget:
>> From: =?UTF-8?q?SZEDER=20G=C3=A1bor?= <[email protected]>
>>
>> clear_##slabname() frees only the memory allocated for a commit slab
>> itself, but entries in the commit slab might own additional memory
>> outside the slab that should be freed as well.  We already have (at
>> least) one such commit slab, and this patch series is about to add one
>> more.
>>
>> To free all additional memory owned by entries on the commit slab the
>> user of such a slab could iterate over all commits it knows about,
>> peek whether there is a valid entry associated with each commit, and
>> free the additional memory, if any.  Or it could rely on intimate
>> knowledge about the internals of the commit slab implementation, and
>> could itself iterate directly through all entries in the slab, and
>> free the additional memory.  Or it could just leak the additional
>> memory...
>>
>> Introduce deep_clear_##slabname() to allow releasing memory owned by
>> commit slab entries by invoking the 'void free_fn(elemtype *ptr)'
>> function specified as parameter for each entry in the slab.
> 
> Adding a new function instead of extending the existing ones makes
> sense, as this is a rare requirement.
> 
>>
>> Use it in get_shallow_commits() in 'shallow.c' to replace an
>> open-coded iteration over a commit slab's entries.
>>
>> Signed-off-by: SZEDER Gábor <[email protected]>
>> Signed-off-by: Derrick Stolee <[email protected]>
>> ---
>>  commit-slab-decl.h |  1 +
>>  commit-slab-impl.h | 13 +++++++++++++
>>  commit-slab.h      | 10 ++++++++++
>>  shallow.c          | 14 +++++---------
>>  4 files changed, 29 insertions(+), 9 deletions(-)
>>
>> diff --git a/commit-slab-decl.h b/commit-slab-decl.h
>> index adc7b46c83b..286164b7e27 100644
>> --- a/commit-slab-decl.h
>> +++ b/commit-slab-decl.h
>> @@ -32,6 +32,7 @@ struct slabname {							\
>>  void init_ ##slabname## _with_stride(struct slabname *s, unsigned stride); \
>>  void init_ ##slabname(struct slabname *s);				\
>>  void clear_ ##slabname(struct slabname *s);				\
>> +void deep_clear_ ##slabname(struct slabname *s, void (*free_fn)(elemtype *ptr)); \
>>  elemtype *slabname## _at_peek(struct slabname *s, const struct commit *c, int add_if_missing); \
>>  elemtype *slabname## _at(struct slabname *s, const struct commit *c);	\
>>  elemtype *slabname## _peek(struct slabname *s, const struct commit *c)
>> diff --git a/commit-slab-impl.h b/commit-slab-impl.h
>> index 5c0eb91a5d1..557738df271 100644
>> --- a/commit-slab-impl.h
>> +++ b/commit-slab-impl.h
>> @@ -38,6 +38,19 @@ scope void clear_ ##slabname(struct slabname *s)			\
>>  	FREE_AND_NULL(s->slab);						\
>>  }									\
>>  									\
>> +scope void deep_clear_ ##slabname(struct slabname *s, void (*free_fn)(elemtype *)) \
>> +{									\
>> +	unsigned int i;							\
>> +	for (i = 0; i < s->slab_count; i++) {				\
>> +		unsigned int j;						\
>> +		if (!s->slab[i])					\
>> +			continue;					\
>> +		for (j = 0; j < s->slab_size; j++)			\
>> +			free_fn(&s->slab[i][j * s->stride]);		\
>> +	}								\
>> +	clear_ ##slabname(s);						> +}									\
> 
> 
> Why pass an elemtype pointer to the callback function instead of
> a plain elemtype?  Because it matches the return type of _at() and
> _peek().  Consistency, good.  Handing it a pointer allows the
> callback to pass it on to free(), though, which would be bad,
> since we do that in clear_() as well.  Hmm.
> 
>> +									\
>>  scope elemtype *slabname## _at_peek(struct slabname *s,			\
>>  						  const struct commit *c, \
>>  						  int add_if_missing)   \
>> diff --git a/commit-slab.h b/commit-slab.h
>> index 05b3f2804e7..8e72a305365 100644
>> --- a/commit-slab.h
>> +++ b/commit-slab.h
>> @@ -47,6 +47,16 @@
>>   *
>>   *   Call this function before the slab falls out of scope to avoid
>>   *   leaking memory.
>> + *
>> + * - void deep_clear_indegree(struct indegree *, void (*free_fn)(int*))
>> + *
>> + *   Empties the slab, similar to clear_indegree(), but in addition it
>> + *   calls the given 'free_fn' for each slab entry to release any
>> + *   additional memory that might be owned by the entry (but not the
>> + *   entry itself!).
>> + *   Note that 'free_fn' might be called even for entries for which no
>> + *   indegree_at() call has been made; in this case 'free_fn' is invoked
>> + *   with a pointer to a zero-initialized location.
>>   */
>>
>>  #define define_commit_slab(slabname, elemtype) \
>> diff --git a/shallow.c b/shallow.c
>> index 7fd04afed19..c4ac8a73273 100644
>> --- a/shallow.c
>> +++ b/shallow.c
>> @@ -84,6 +84,10 @@ int is_repository_shallow(struct repository *r)
>>   * supports a "valid" flag.
>>   */
>>  define_commit_slab(commit_depth, int *);
>> +static void free_depth_in_slab(int **ptr)
>> +{
>> +	FREE_AND_NULL(*ptr);
>> +}
> 
> Why FREE_AND_NULL?  The original loop below called free().  The slabs
> are all released by deep_clear_() immediately after the callbacks are
> done anyway, so what's the point in zeroing these pointers?

I think the point was that a later change was going to free
elements in the slab on a one-by-one basis while computing
the filters, to save memory overall. To be future-proof
against such a change, we need to NULL the pointers here.

Perhaps that viewpoint also answers your other comment about
"why pass the pointer?"

Thanks,
-Stolee

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On the Git mailing list, SZEDER Gábor wrote (reply to this):

On Fri, Jun 05, 2020 at 01:00:26PM +0000, SZEDER Gábor via GitGitGadget wrote:
> From: =?UTF-8?q?SZEDER=20G=C3=A1bor?= <[email protected]>
> 
> clear_##slabname() frees only the memory allocated for a commit slab
> itself, but entries in the commit slab might own additional memory
> outside the slab that should be freed as well.  We already have (at
> least) one such commit slab, and this patch series is about to add one
> more.

This was only true in my original submission, but not anymore: this
patch series doesn't add another such slab, and, more importantly, now
we have at least two such commit slabs.  deep_clear_##slabnmae() could
be used to clear the bloom_filter_slab and all memory attached to it,
which at the moment is just leaked.

> To free all additional memory owned by entries on the commit slab the
> user of such a slab could iterate over all commits it knows about,
> peek whether there is a valid entry associated with each commit, and
> free the additional memory, if any.  Or it could rely on intimate
> knowledge about the internals of the commit slab implementation, and
> could itself iterate directly through all entries in the slab, and
> free the additional memory.  Or it could just leak the additional
> memory...
> 
> Introduce deep_clear_##slabname() to allow releasing memory owned by
> commit slab entries by invoking the 'void free_fn(elemtype *ptr)'
> function specified as parameter for each entry in the slab.
> 
> Use it in get_shallow_commits() in 'shallow.c' to replace an
> open-coded iteration over a commit slab's entries.
> 
> Signed-off-by: SZEDER Gábor <[email protected]>
> Signed-off-by: Derrick Stolee <[email protected]>
> ---
>  commit-slab-decl.h |  1 +
>  commit-slab-impl.h | 13 +++++++++++++
>  commit-slab.h      | 10 ++++++++++
>  shallow.c          | 14 +++++---------
>  4 files changed, 29 insertions(+), 9 deletions(-)
> 
> diff --git a/commit-slab-decl.h b/commit-slab-decl.h
> index adc7b46c83b..286164b7e27 100644
> --- a/commit-slab-decl.h
> +++ b/commit-slab-decl.h
> @@ -32,6 +32,7 @@ struct slabname {							\
>  void init_ ##slabname## _with_stride(struct slabname *s, unsigned stride); \
>  void init_ ##slabname(struct slabname *s);				\
>  void clear_ ##slabname(struct slabname *s);				\
> +void deep_clear_ ##slabname(struct slabname *s, void (*free_fn)(elemtype *ptr)); \
>  elemtype *slabname## _at_peek(struct slabname *s, const struct commit *c, int add_if_missing); \
>  elemtype *slabname## _at(struct slabname *s, const struct commit *c);	\
>  elemtype *slabname## _peek(struct slabname *s, const struct commit *c)
> diff --git a/commit-slab-impl.h b/commit-slab-impl.h
> index 5c0eb91a5d1..557738df271 100644
> --- a/commit-slab-impl.h
> +++ b/commit-slab-impl.h
> @@ -38,6 +38,19 @@ scope void clear_ ##slabname(struct slabname *s)			\
>  	FREE_AND_NULL(s->slab);						\
>  }									\
>  									\
> +scope void deep_clear_ ##slabname(struct slabname *s, void (*free_fn)(elemtype *)) \
> +{									\
> +	unsigned int i;							\
> +	for (i = 0; i < s->slab_count; i++) {				\
> +		unsigned int j;						\
> +		if (!s->slab[i])					\
> +			continue;					\
> +		for (j = 0; j < s->slab_size; j++)			\
> +			free_fn(&s->slab[i][j * s->stride]);		\
> +	}								\
> +	clear_ ##slabname(s);						\
> +}									\
> +									\
>  scope elemtype *slabname## _at_peek(struct slabname *s,			\
>  						  const struct commit *c, \
>  						  int add_if_missing)   \
> diff --git a/commit-slab.h b/commit-slab.h
> index 05b3f2804e7..8e72a305365 100644
> --- a/commit-slab.h
> +++ b/commit-slab.h
> @@ -47,6 +47,16 @@
>   *
>   *   Call this function before the slab falls out of scope to avoid
>   *   leaking memory.
> + *
> + * - void deep_clear_indegree(struct indegree *, void (*free_fn)(int*))
> + *
> + *   Empties the slab, similar to clear_indegree(), but in addition it
> + *   calls the given 'free_fn' for each slab entry to release any
> + *   additional memory that might be owned by the entry (but not the
> + *   entry itself!).
> + *   Note that 'free_fn' might be called even for entries for which no
> + *   indegree_at() call has been made; in this case 'free_fn' is invoked
> + *   with a pointer to a zero-initialized location.
>   */
>  
>  #define define_commit_slab(slabname, elemtype) \
> diff --git a/shallow.c b/shallow.c
> index 7fd04afed19..c4ac8a73273 100644
> --- a/shallow.c
> +++ b/shallow.c
> @@ -84,6 +84,10 @@ int is_repository_shallow(struct repository *r)
>   * supports a "valid" flag.
>   */
>  define_commit_slab(commit_depth, int *);
> +static void free_depth_in_slab(int **ptr)
> +{
> +	FREE_AND_NULL(*ptr);
> +}
>  struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
>  		int shallow_flag, int not_shallow_flag)
>  {
> @@ -150,15 +154,7 @@ struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
>  			}
>  		}
>  	}
> -	for (i = 0; i < depths.slab_count; i++) {
> -		int j;
> -
> -		if (!depths.slab[i])
> -			continue;
> -		for (j = 0; j < depths.slab_size; j++)
> -			free(depths.slab[i][j]);
> -	}
> -	clear_commit_depth(&depths);
> +	deep_clear_commit_depth(&depths, free_depth_in_slab);
>  
>  	return result;
>  }
> -- 
> gitgitgadget
>

void init_ ##slabname(struct slabname *s); \
void clear_ ##slabname(struct slabname *s); \
void deep_clear_ ##slabname(struct slabname *s, void (*free_fn)(elemtype *ptr)); \
elemtype *slabname## _at_peek(struct slabname *s, const struct commit *c, int add_if_missing); \
elemtype *slabname## _at(struct slabname *s, const struct commit *c); \
elemtype *slabname## _peek(struct slabname *s, const struct commit *c)
Expand Down
13 changes: 13 additions & 0 deletions commit-slab-impl.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -38,6 +38,19 @@ scope void clear_ ##slabname(struct slabname *s) \
FREE_AND_NULL(s->slab); \
} \
\
scope void deep_clear_ ##slabname(struct slabname *s, void (*free_fn)(elemtype *)) \
{ \
unsigned int i; \
for (i = 0; i < s->slab_count; i++) { \
unsigned int j; \
if (!s->slab[i]) \
continue; \
for (j = 0; j < s->slab_size; j++) \
free_fn(&s->slab[i][j * s->stride]); \
} \
clear_ ##slabname(s); \
} \
\
scope elemtype *slabname## _at_peek(struct slabname *s, \
const struct commit *c, \
int add_if_missing) \
Expand Down
10 changes: 10 additions & 0 deletions commit-slab.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -47,6 +47,16 @@
*
* Call this function before the slab falls out of scope to avoid
* leaking memory.
*
* - void deep_clear_indegree(struct indegree *, void (*free_fn)(int*))
*
* Empties the slab, similar to clear_indegree(), but in addition it
* calls the given 'free_fn' for each slab entry to release any
* additional memory that might be owned by the entry (but not the
* entry itself!).
* Note that 'free_fn' might be called even for entries for which no
* indegree_at() call has been made; in this case 'free_fn' is invoked
* with a pointer to a zero-initialized location.
*/

#define define_commit_slab(slabname, elemtype) \
Expand Down
10 changes: 5 additions & 5 deletions diff.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -431,11 +431,11 @@ struct combine_diff_path *diff_tree_paths(
struct combine_diff_path *p, const struct object_id *oid,
const struct object_id **parents_oid, int nparent,
struct strbuf *base, struct diff_options *opt);
int diff_tree_oid(const struct object_id *old_oid,
const struct object_id *new_oid,
const char *base, struct diff_options *opt);
int diff_root_tree_oid(const struct object_id *new_oid, const char *base,
struct diff_options *opt);
void diff_tree_oid(const struct object_id *old_oid,
const struct object_id *new_oid,
const char *base, struct diff_options *opt);
void diff_root_tree_oid(const struct object_id *new_oid, const char *base,
struct diff_options *opt);

struct combine_diff_path {
struct combine_diff_path *next;
Expand Down
9 changes: 3 additions & 6 deletions revision.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -791,9 +791,7 @@ static int rev_compare_tree(struct rev_info *revs,

tree_difference = REV_TREE_SAME;
revs->pruning.flags.has_changes = 0;
if (diff_tree_oid(&t1->object.oid, &t2->object.oid, "",
&revs->pruning) < 0)
return REV_TREE_DIFFERENT;
diff_tree_oid(&t1->object.oid, &t2->object.oid, "", &revs->pruning);

if (!nth_parent)
if (bloom_ret == 1 && tree_difference == REV_TREE_SAME)
Expand All @@ -804,17 +802,16 @@ static int rev_compare_tree(struct rev_info *revs,

static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
{
int retval;
struct tree *t1 = get_commit_tree(commit);

if (!t1)
return 0;

tree_difference = REV_TREE_SAME;
revs->pruning.flags.has_changes = 0;
retval = diff_tree_oid(NULL, &t1->object.oid, "", &revs->pruning);
diff_tree_oid(NULL, &t1->object.oid, "", &revs->pruning);

return retval >= 0 && (tree_difference == REV_TREE_SAME);
return tree_difference == REV_TREE_SAME;
}

struct treesame_state {
Expand Down
14 changes: 5 additions & 9 deletions shallow.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -84,6 +84,10 @@ int is_repository_shallow(struct repository *r)
* supports a "valid" flag.
*/
define_commit_slab(commit_depth, int *);
static void free_depth_in_slab(int **ptr)
{
FREE_AND_NULL(*ptr);
}
struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
int shallow_flag, int not_shallow_flag)
{
Expand Down Expand Up @@ -150,15 +154,7 @@ struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
}
}
}
for (i = 0; i < depths.slab_count; i++) {
int j;

if (!depths.slab[i])
continue;
for (j = 0; j < depths.slab_size; j++)
free(depths.slab[i][j]);
}
clear_commit_depth(&depths);
deep_clear_commit_depth(&depths, free_depth_in_slab);

return result;
}
Expand Down
4 changes: 3 additions & 1 deletion t/t4010-diff-pathspec.sh
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -125,7 +125,9 @@ test_expect_success 'setup submodules' '
test_expect_success 'diff-tree ignores trailing slash on submodule path' '
git diff --name-only HEAD^ HEAD submod >expect &&
git diff --name-only HEAD^ HEAD submod/ >actual &&
test_cmp expect actual
test_cmp expect actual &&
git diff --name-only HEAD^ HEAD -- submod/whatever >actual &&
test_must_be_empty actual
'

test_expect_success 'diff multiple wildcard pathspecs' '
Expand Down
5 changes: 3 additions & 2 deletions t/t5318-commit-graph.sh
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -488,7 +488,7 @@ test_expect_success 'detect bad hash version' '
'

test_expect_success 'detect low chunk count' '
corrupt_graph_and_verify $GRAPH_BYTE_CHUNK_COUNT "\02" \
corrupt_graph_and_verify $GRAPH_BYTE_CHUNK_COUNT "\01" \
"missing the .* chunk"
'

Expand Down Expand Up @@ -574,7 +574,8 @@ test_expect_success 'detect invalid checksum hash' '

test_expect_success 'detect incorrect chunk count' '
corrupt_graph_and_verify $GRAPH_BYTE_CHUNK_COUNT "\377" \
"chunk lookup table entry missing" $GRAPH_CHUNK_LOOKUP_OFFSET
"commit-graph file is too small to hold [0-9]* chunks" \
$GRAPH_CHUNK_LOOKUP_OFFSET
'

test_expect_success 'git fsck (checks commit-graph)' '
Expand Down
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