From: Taylor Blau <me@ttaylorr.com>
To: git@vger.kernel.org
Cc: Jeff King <peff@peff.net>, Elijah Newren <newren@gmail.com>,
Patrick Steinhardt <ps@pks.im>,
Junio C Hamano <gitster@pobox.com>
Subject: [PATCH v3 20/30] pseudo-merge: scaffolding for reads
Date: Tue, 21 May 2024 15:02:41 -0400 [thread overview]
Message-ID: <3cc5434e44e09e8ba5f73df602bc3801112fa8c0.1716318089.git.me@ttaylorr.com> (raw)
In-Reply-To: <cover.1716318088.git.me@ttaylorr.com>
Implement scaffolding within the new pseudo-merge compilation unit
necessary to use the pseudo-merge API from within the pack-bitmap.c
machinery.
The core of this scaffolding is two-fold:
- The `pseudo_merge` structure itself, which represents an individual
pseudo-merge bitmap. It has fields for both bitmaps, as well as
metadata about its position within the memory-mapped region, and
a few extra bits indicating whether or not it is satisfied, and
which bitmaps(s, if any) have been read, since they are initialized
lazily.
- The `pseudo_merge_map` structure, which holds an array of
pseudo_merges, as well as a pointer to the memory-mapped region
containing the pseudo-merge serialization from within a .bitmap
file.
Note that the `bitmap_index` structure is defined statically within the
pack-bitmap.o compilation unit, so we can't take in a `struct
bitmap_index *`. Instead, wrap the primary components necessary to read
the pseudo-merges in this new structure to avoid exposing the
implementation details of the `bitmap_index` structure.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
---
pseudo-merge.c | 10 ++++++++
pseudo-merge.h | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 75 insertions(+)
diff --git a/pseudo-merge.c b/pseudo-merge.c
index 4be730563eb..1aca70ecdfb 100644
--- a/pseudo-merge.c
+++ b/pseudo-merge.c
@@ -454,3 +454,13 @@ void select_pseudo_merges(struct bitmap_writer *writer,
stop_progress(&progress);
}
+
+void free_pseudo_merge_map(struct pseudo_merge_map *pm)
+{
+ uint32_t i;
+ for (i = 0; i < pm->nr; i++) {
+ ewah_pool_free(pm->v[i].commits);
+ ewah_pool_free(pm->v[i].bitmap);
+ }
+ free(pm->v);
+}
diff --git a/pseudo-merge.h b/pseudo-merge.h
index cab54daf14b..a3f0243062c 100644
--- a/pseudo-merge.h
+++ b/pseudo-merge.h
@@ -97,4 +97,69 @@ struct pseudo_merge_commit_idx {
void select_pseudo_merges(struct bitmap_writer *writer,
struct commit **commits, size_t commits_nr);
+/*
+ * Represents a serialized view of a file containing pseudo-merge(s)
+ * (see Documentation/technical/bitmap-format.txt for a specification
+ * of the format).
+ */
+struct pseudo_merge_map {
+ /*
+ * An array of pseudo-merge(s), lazily loaded from the .bitmap
+ * file.
+ */
+ struct pseudo_merge *v;
+ size_t nr;
+ size_t commits_nr;
+
+ /*
+ * Pointers into a memory-mapped view of the .bitmap file:
+ *
+ * - map: the beginning of the .bitmap file
+ * - commits: the beginning of the pseudo-merge commit index
+ * - map_size: the size of the .bitmap file
+ */
+ const unsigned char *map;
+ const unsigned char *commits;
+
+ size_t map_size;
+};
+
+/*
+ * An individual pseudo-merge, storing a pair of lazily-loaded
+ * bitmaps:
+ *
+ * - commits: the set of commit(s) that are part of the pseudo-merge
+ * - bitmap: the set of object(s) reachable from the above set of
+ * commits.
+ *
+ * The `at` and `bitmap_at` fields are used to store the locations of
+ * each of the above bitmaps in the .bitmap file.
+ */
+struct pseudo_merge {
+ struct ewah_bitmap *commits;
+ struct ewah_bitmap *bitmap;
+
+ off_t at;
+ off_t bitmap_at;
+
+ /*
+ * `satisfied` indicates whether the given pseudo-merge has been
+ * used.
+ *
+ * `loaded_commits` and `loaded_bitmap` indicate whether the
+ * respective bitmaps have been loaded and read from the
+ * .bitmap file.
+ */
+ unsigned satisfied : 1,
+ loaded_commits : 1,
+ loaded_bitmap : 1;
+};
+
+/*
+ * Frees the given pseudo-merge map, releasing any memory held by (a)
+ * parsed EWAH bitmaps, or (b) the array of pseudo-merges itself. Does
+ * not free the memory-mapped view of the .bitmap file.
+ */
+void free_pseudo_merge_map(struct pseudo_merge_map *pm);
+
#endif
--
2.45.1.175.gbea44add9db
next prev parent reply other threads:[~2024-05-21 19:02 UTC|newest]
Thread overview: 157+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-20 22:04 [PATCH 00/24] pack-bitmap: pseudo-merge reachability bitmaps Taylor Blau
2024-03-20 22:05 ` [PATCH 01/24] Documentation/technical: describe pseudo-merge bitmaps format Taylor Blau
2024-03-21 21:24 ` Junio C Hamano
2024-03-21 22:13 ` Taylor Blau
2024-03-21 22:22 ` Junio C Hamano
2024-03-20 22:05 ` [PATCH 02/24] config: repo_config_get_expiry() Taylor Blau
2024-04-10 17:54 ` Jeff King
2024-04-29 19:39 ` Taylor Blau
2024-03-20 22:05 ` [PATCH 03/24] ewah: implement `ewah_bitmap_is_subset()` Taylor Blau
2024-04-10 18:05 ` Jeff King
2024-04-29 19:47 ` Taylor Blau
2024-03-20 22:05 ` [PATCH 04/24] pack-bitmap: drop unused `max_bitmaps` parameter Taylor Blau
2024-04-10 18:06 ` Jeff King
2024-03-20 22:05 ` [PATCH 05/24] pack-bitmap: move some initialization to `bitmap_writer_init()` Taylor Blau
2024-04-10 18:10 ` Jeff King
2024-03-20 22:05 ` [PATCH 06/24] pseudo-merge.ch: initial commit Taylor Blau
2024-03-20 22:05 ` [PATCH 07/24] pack-bitmap-write: support storing pseudo-merge commits Taylor Blau
2024-03-20 22:05 ` [PATCH 08/24] pack-bitmap: implement `bitmap_writer_has_bitmapped_object_id()` Taylor Blau
2024-03-20 22:05 ` [PATCH 09/24] pack-bitmap: make `bitmap_writer_push_bitmapped_commit()` public Taylor Blau
2024-03-20 22:05 ` [PATCH 10/24] pseudo-merge: implement support for selecting pseudo-merge commits Taylor Blau
2024-03-20 22:05 ` [PATCH 11/24] pack-bitmap-write.c: select " Taylor Blau
2024-03-20 22:05 ` [PATCH 12/24] pack-bitmap-write.c: write pseudo-merge table Taylor Blau
2024-03-20 22:05 ` [PATCH 13/24] pack-bitmap: extract `read_bitmap()` function Taylor Blau
2024-03-20 22:05 ` [PATCH 14/24] pseudo-merge: scaffolding for reads Taylor Blau
2024-03-20 22:05 ` [PATCH 15/24] pack-bitmap.c: read pseudo-merge extension Taylor Blau
2024-03-20 22:05 ` [PATCH 16/24] pseudo-merge: implement support for reading pseudo-merge commits Taylor Blau
2024-03-20 22:05 ` [PATCH 17/24] ewah: implement `ewah_bitmap_popcount()` Taylor Blau
2024-03-20 22:05 ` [PATCH 18/24] pack-bitmap: implement test helpers for pseudo-merge Taylor Blau
2024-03-20 22:05 ` [PATCH 19/24] t/test-lib-functions.sh: support `--date` in `test_commit_bulk()` Taylor Blau
2024-03-20 22:05 ` [PATCH 20/24] pack-bitmap.c: use pseudo-merges during traversal Taylor Blau
2024-03-20 22:06 ` [PATCH 21/24] pack-bitmap: extra trace2 information Taylor Blau
2024-03-20 22:06 ` [PATCH 22/24] ewah: `bitmap_equals_ewah()` Taylor Blau
2024-03-20 22:06 ` [PATCH 23/24] pseudo-merge: implement support for finding existing merges Taylor Blau
2024-03-20 22:06 ` [PATCH 24/24] t/perf: implement performace tests for pseudo-merge bitmaps Taylor Blau
2024-03-21 19:50 ` [PATCH 00/24] pack-bitmap: pseudo-merge reachability bitmaps Junio C Hamano
2024-04-29 20:42 ` [PATCH v2 00/23] " Taylor Blau
2024-04-29 20:42 ` [PATCH v2 01/23] Documentation/technical: describe pseudo-merge bitmaps format Taylor Blau
2024-05-06 11:52 ` Patrick Steinhardt
2024-05-06 16:37 ` Taylor Blau
2024-05-10 11:46 ` Patrick Steinhardt
2024-05-13 19:47 ` Taylor Blau
2024-05-14 6:33 ` Patrick Steinhardt
2024-04-29 20:43 ` [PATCH v2 02/23] ewah: implement `ewah_bitmap_is_subset()` Taylor Blau
2024-04-29 20:43 ` [PATCH v2 03/23] pack-bitmap: drop unused `max_bitmaps` parameter Taylor Blau
2024-04-29 20:43 ` [PATCH v2 04/23] pack-bitmap: move some initialization to `bitmap_writer_init()` Taylor Blau
2024-05-06 11:52 ` Patrick Steinhardt
2024-05-06 18:24 ` Taylor Blau
2024-04-29 20:43 ` [PATCH v2 05/23] pseudo-merge.ch: initial commit Taylor Blau
2024-04-29 20:43 ` [PATCH v2 06/23] pack-bitmap-write: support storing pseudo-merge commits Taylor Blau
2024-05-06 11:52 ` Patrick Steinhardt
2024-05-06 18:48 ` Taylor Blau
2024-05-10 11:47 ` Patrick Steinhardt
2024-05-13 18:42 ` Jeff King
2024-05-13 20:19 ` Taylor Blau
2024-04-29 20:43 ` [PATCH v2 07/23] pack-bitmap: implement `bitmap_writer_has_bitmapped_object_id()` Taylor Blau
2024-04-29 20:43 ` [PATCH v2 08/23] pack-bitmap: make `bitmap_writer_push_bitmapped_commit()` public Taylor Blau
2024-05-13 18:50 ` Jeff King
2024-05-14 0:54 ` Taylor Blau
2024-04-29 20:43 ` [PATCH v2 09/23] pseudo-merge: implement support for selecting pseudo-merge commits Taylor Blau
2024-05-06 11:53 ` Patrick Steinhardt
2024-05-06 19:58 ` Taylor Blau
2024-05-13 19:03 ` Jeff King
2024-05-14 0:58 ` Taylor Blau
2024-05-16 8:07 ` Jeff King
2024-05-16 22:43 ` Junio C Hamano
2024-04-29 20:43 ` [PATCH v2 10/23] pack-bitmap-write.c: select " Taylor Blau
2024-05-06 11:53 ` Patrick Steinhardt
2024-05-06 20:05 ` Taylor Blau
2024-05-10 11:47 ` Patrick Steinhardt
2024-04-29 20:43 ` [PATCH v2 11/23] pack-bitmap-write.c: write pseudo-merge table Taylor Blau
2024-04-29 20:43 ` [PATCH v2 12/23] pack-bitmap: extract `read_bitmap()` function Taylor Blau
2024-04-29 20:43 ` [PATCH v2 13/23] pseudo-merge: scaffolding for reads Taylor Blau
2024-04-29 20:43 ` [PATCH v2 14/23] pack-bitmap.c: read pseudo-merge extension Taylor Blau
2024-04-29 20:44 ` [PATCH v2 15/23] pseudo-merge: implement support for reading pseudo-merge commits Taylor Blau
2024-04-29 20:44 ` [PATCH v2 16/23] ewah: implement `ewah_bitmap_popcount()` Taylor Blau
2024-04-29 20:44 ` [PATCH v2 17/23] pack-bitmap: implement test helpers for pseudo-merge Taylor Blau
2024-04-29 20:44 ` [PATCH v2 18/23] t/test-lib-functions.sh: support `--date` in `test_commit_bulk()` Taylor Blau
2024-04-29 20:44 ` [PATCH v2 19/23] pack-bitmap.c: use pseudo-merges during traversal Taylor Blau
2024-04-29 20:44 ` [PATCH v2 20/23] pack-bitmap: extra trace2 information Taylor Blau
2024-04-29 20:44 ` [PATCH v2 21/23] ewah: `bitmap_equals_ewah()` Taylor Blau
2024-04-29 20:44 ` [PATCH v2 22/23] pseudo-merge: implement support for finding existing merges Taylor Blau
2024-04-29 20:44 ` [PATCH v2 23/23] t/perf: implement performace tests for pseudo-merge bitmaps Taylor Blau
2024-04-30 20:03 ` [PATCH v2 00/23] pack-bitmap: pseudo-merge reachability bitmaps Junio C Hamano
2024-05-01 14:40 ` Taylor Blau
2024-05-21 19:01 ` [PATCH v3 00/30] " Taylor Blau
2024-05-21 19:01 ` [PATCH v3 01/30] object.h: add flags allocated by pack-bitmap.h Taylor Blau
2024-05-21 19:06 ` Taylor Blau
2024-05-21 19:01 ` [PATCH v3 07/30] Documentation/gitpacking.txt: initial commit Taylor Blau
2024-05-21 19:02 ` [PATCH v3 08/30] Documentation/gitpacking.txt: describe pseudo-merge bitmaps Taylor Blau
2024-05-21 19:02 ` [PATCH v3 09/30] Documentation/technical: describe pseudo-merge bitmaps format Taylor Blau
2024-05-21 19:02 ` [PATCH v3 10/30] ewah: implement `ewah_bitmap_is_subset()` Taylor Blau
2024-05-21 19:02 ` [PATCH v3 11/30] pack-bitmap: move some initialization to `bitmap_writer_init()` Taylor Blau
2024-05-21 19:02 ` [PATCH v3 12/30] pseudo-merge.ch: initial commit Taylor Blau
2024-05-21 19:02 ` [PATCH v3 13/30] pack-bitmap-write: support storing pseudo-merge commits Taylor Blau
2024-05-21 19:02 ` [PATCH v3 14/30] pack-bitmap: implement `bitmap_writer_has_bitmapped_object_id()` Taylor Blau
2024-05-21 19:02 ` [PATCH v3 15/30] pack-bitmap: make `bitmap_writer_push_bitmapped_commit()` public Taylor Blau
2024-05-21 19:02 ` [PATCH v3 16/30] config: introduce git_config_float() Taylor Blau
2024-05-23 10:02 ` Jeff King
2024-05-23 17:51 ` Taylor Blau
2024-05-21 19:02 ` [PATCH v3 17/30] pseudo-merge: implement support for selecting pseudo-merge commits Taylor Blau
2024-05-23 10:12 ` Jeff King
2024-05-23 17:56 ` Taylor Blau
2024-05-21 19:02 ` [PATCH v3 18/30] pack-bitmap-write.c: write pseudo-merge table Taylor Blau
2024-05-21 19:02 ` [PATCH v3 19/30] pack-bitmap: extract `read_bitmap()` function Taylor Blau
2024-05-21 19:02 ` Taylor Blau [this message]
2024-05-21 19:02 ` [PATCH v3 21/30] pack-bitmap.c: read pseudo-merge extension Taylor Blau
2024-05-21 19:02 ` [PATCH v3 22/30] pseudo-merge: implement support for reading pseudo-merge commits Taylor Blau
2024-05-23 10:40 ` Jeff King
2024-05-23 18:09 ` Taylor Blau
2024-05-21 19:02 ` [PATCH v3 23/30] ewah: implement `ewah_bitmap_popcount()` Taylor Blau
2024-05-21 19:02 ` [PATCH v3 24/30] pack-bitmap: implement test helpers for pseudo-merge Taylor Blau
2024-05-21 19:02 ` [PATCH v3 25/30] t/test-lib-functions.sh: support `--date` in `test_commit_bulk()` Taylor Blau
2024-05-23 10:42 ` Jeff King
2024-05-23 15:45 ` Junio C Hamano
2024-05-23 18:23 ` Taylor Blau
2024-05-21 19:03 ` [PATCH v3 26/30] pack-bitmap.c: use pseudo-merges during traversal Taylor Blau
2024-05-23 10:48 ` Jeff King
2024-05-23 18:23 ` Taylor Blau
2024-05-21 19:03 ` [PATCH v3 27/30] pack-bitmap: extra trace2 information Taylor Blau
2024-05-21 19:03 ` [PATCH v3 28/30] ewah: `bitmap_equals_ewah()` Taylor Blau
2024-05-21 19:03 ` [PATCH v3 29/30] pseudo-merge: implement support for finding existing merges Taylor Blau
2024-05-21 19:03 ` [PATCH v3 30/30] t/perf: implement performace tests for pseudo-merge bitmaps Taylor Blau
2024-05-23 10:54 ` Jeff King
2024-05-23 19:53 ` Taylor Blau
2024-05-25 3:13 ` Jeff King
2024-05-23 11:05 ` [PATCH v3 00/30] pack-bitmap: pseudo-merge reachability bitmaps Jeff King
2024-05-23 20:04 ` Taylor Blau
2024-05-25 3:15 ` Jeff King
2024-05-23 20:42 ` Taylor Blau
2024-05-23 21:26 ` [PATCH v4 00/24] " Taylor Blau
2024-05-23 21:26 ` [PATCH v4 01/24] Documentation/gitpacking.txt: initial commit Taylor Blau
2024-05-23 21:26 ` [PATCH v4 02/24] Documentation/gitpacking.txt: describe pseudo-merge bitmaps Taylor Blau
2024-05-23 21:26 ` [PATCH v4 03/24] Documentation/technical: describe pseudo-merge bitmaps format Taylor Blau
2024-05-23 21:26 ` [PATCH v4 04/24] ewah: implement `ewah_bitmap_is_subset()` Taylor Blau
2024-05-23 21:26 ` [PATCH v4 05/24] pack-bitmap: move some initialization to `bitmap_writer_init()` Taylor Blau
2024-05-23 21:26 ` [PATCH v4 06/24] pseudo-merge.ch: initial commit Taylor Blau
2024-05-23 21:26 ` [PATCH v4 07/24] pack-bitmap-write: support storing pseudo-merge commits Taylor Blau
2024-05-23 21:26 ` [PATCH v4 08/24] pack-bitmap: implement `bitmap_writer_has_bitmapped_object_id()` Taylor Blau
2024-05-23 21:26 ` [PATCH v4 09/24] pack-bitmap: make `bitmap_writer_push_bitmapped_commit()` public Taylor Blau
2024-05-23 21:26 ` [PATCH v4 10/24] config: introduce `git_config_double()` Taylor Blau
2024-05-23 21:26 ` [PATCH v4 11/24] pseudo-merge: implement support for selecting pseudo-merge commits Taylor Blau
2024-05-25 3:22 ` Jeff King
2024-05-23 21:26 ` [PATCH v4 12/24] pack-bitmap-write.c: write pseudo-merge table Taylor Blau
2024-05-23 21:26 ` [PATCH v4 13/24] pack-bitmap: extract `read_bitmap()` function Taylor Blau
2024-05-23 21:26 ` [PATCH v4 14/24] pseudo-merge: scaffolding for reads Taylor Blau
2024-05-23 21:26 ` [PATCH v4 15/24] pack-bitmap.c: read pseudo-merge extension Taylor Blau
2024-05-23 21:26 ` [PATCH v4 16/24] pseudo-merge: implement support for reading pseudo-merge commits Taylor Blau
2024-05-23 21:27 ` [PATCH v4 17/24] ewah: implement `ewah_bitmap_popcount()` Taylor Blau
2024-05-23 21:27 ` [PATCH v4 18/24] pack-bitmap: implement test helpers for pseudo-merge Taylor Blau
2024-05-23 21:27 ` [PATCH v4 19/24] t/test-lib-functions.sh: support `--notick` in `test_commit_bulk()` Taylor Blau
2024-05-25 3:25 ` Jeff King
2024-05-23 21:27 ` [PATCH v4 20/24] pack-bitmap.c: use pseudo-merges during traversal Taylor Blau
2024-05-23 21:27 ` [PATCH v4 21/24] pack-bitmap: extra trace2 information Taylor Blau
2024-05-23 21:27 ` [PATCH v4 22/24] ewah: `bitmap_equals_ewah()` Taylor Blau
2024-05-23 21:27 ` [PATCH v4 23/24] pseudo-merge: implement support for finding existing merges Taylor Blau
2024-05-23 21:27 ` [PATCH v4 24/24] t/perf: implement performance tests for pseudo-merge bitmaps Taylor Blau
2024-05-25 3:26 ` [PATCH v4 00/24] pack-bitmap: pseudo-merge reachability bitmaps Jeff King
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