The traverse_trees() and traverse_trees_recursive() functions call each
other recursively. In a deep tree, this can result in running out of
stack space and crashing.
There's obviously going to be some limit here based on available stack,
but the problem is exacerbated by a few large structs, many of which we
over-allocate. For example, in traverse_trees() we store a name_entry
and tree_desc_x per tree, both of which contain an object_id (which is
now 32 bytes). And we allocate 8 of them (from MAX_TRAVERSE_TREES), even
though many traversals will only look at 1 or 2.
Interestingly, we used to allocate these on the heap, prior to
8dd40c0472 (traverse_trees(): use stack array for name entries,
2020-01-30). That commit was trying to simplify away allocation size
computations, and naively assumed that the sizes were small enough not
to matter. And they don't in normal cases, but on my stock Debian system
I see a crash running "git archive" on a tree with ~3600 entries.
That's deep enough we wouldn't see it in practice, but probably shallow
enough that we'd prefer not to make it a hard limit. Especially because
other systems may have even smaller stacks.
We can replace these stack variables with a few malloc invocations. This
reduces the stack sizes for the two functions from 1128 and 752 bytes,
respectively, down to 40 and 92 bytes. That allows a depth of ~13000 on
my machine (the improvement isn't in linear proportion because my
numbers don't count the size of parameters and other function overhead).
The possible downsides are:
1. We now have to remember to free(). But both functions have an easy
single exit (and already had to clean up other bits anyway).
2. The extra malloc()/free() overhead might be measurable. I tested
this by setting up a 3000-depth tree with a single blob and running
"git archive" on it. After switching to the heap, it consistently
runs 2-3% faster! Presumably this is because the 1K+ of wasted
stack space penalized memory caches.
On a more real-world case like linux.git, the speed difference isn't
measurable at all, simply because most trees aren't that deep and
there's so much other work going on (like accessing the objects
themselves). So the improvement I saw should be taken as evidence that
we're not making anything worse, but isn't really that interesting on
its own. The main motivation here is that we're now less likely to run
out of stack space and crash.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The vast majority of files including object-store.h did not need dir.h
nor khash.h. Split the header into two files, and let most just depend
upon object-store-ll.h, while letting the two callers that need it
depend on the full object-store.h.
After this patch:
$ git grep -h include..object-store | sort | uniq -c
2 #include "object-store.h"
129 #include "object-store-ll.h"
Diff best viewed with `--color-moved`.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since this header showed up in some places besides just #include
statements, update/clean-up/remove those other places as well.
Note that compat/fsmonitor/fsm-path-utils-darwin.c previously got
away with violating the rule that all files must start with an include
of git-compat-util.h (or a short-list of alternate headers that happen
to include it first). This change exposed the violation and caused it
to stop building correctly; fix it by having it include
git-compat-util.h first, as per policy.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
For the functions defined in read-cache.c, move their declarations from
cache.h to a new header, read-cache-ll.h. Also move some related inline
functions from cache.h to read-cache.h. The purpose of the
read-cache-ll.h/read-cache.h split is that about 70% of the sites don't
need the inline functions and the extra headers they include.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More header clean-up.
* en/header-split-cache-h-part-2: (22 commits)
reftable: ensure git-compat-util.h is the first (indirect) include
diff.h: reduce unnecessary includes
object-store.h: reduce unnecessary includes
commit.h: reduce unnecessary includes
fsmonitor: reduce includes of cache.h
cache.h: remove unnecessary headers
treewide: remove cache.h inclusion due to previous changes
cache,tree: move basic name compare functions from read-cache to tree
cache,tree: move cmp_cache_name_compare from tree.[ch] to read-cache.c
hash-ll.h: split out of hash.h to remove dependency on repository.h
tree-diff.c: move S_DIFFTREE_IFXMIN_NEQ define from cache.h
dir.h: move DTYPE defines from cache.h
versioncmp.h: move declarations for versioncmp.c functions from cache.h
ws.h: move declarations for ws.c functions from cache.h
match-trees.h: move declarations for match-trees.c functions from cache.h
pkt-line.h: move declarations for pkt-line.c functions from cache.h
base85.h: move declarations for base85.c functions from cache.h
copy.h: move declarations for copy.c functions from cache.h
server-info.h: move declarations for server-info.c functions from cache.h
packfile.h: move pack_window and pack_entry from cache.h
...
Header clean-up.
* en/header-split-cache-h: (24 commits)
protocol.h: move definition of DEFAULT_GIT_PORT from cache.h
mailmap, quote: move declarations of global vars to correct unit
treewide: reduce includes of cache.h in other headers
treewide: remove double forward declaration of read_in_full
cache.h: remove unnecessary includes
treewide: remove cache.h inclusion due to pager.h changes
pager.h: move declarations for pager.c functions from cache.h
treewide: remove cache.h inclusion due to editor.h changes
editor: move editor-related functions and declarations into common file
treewide: remove cache.h inclusion due to object.h changes
object.h: move some inline functions and defines from cache.h
treewide: remove cache.h inclusion due to object-file.h changes
object-file.h: move declarations for object-file.c functions from cache.h
treewide: remove cache.h inclusion due to git-zlib changes
git-zlib: move declarations for git-zlib functions from cache.h
treewide: remove cache.h inclusion due to object-name.h changes
object-name.h: move declarations for object-name.c functions from cache.h
treewide: remove unnecessary cache.h inclusion
treewide: be explicit about dependence on mem-pool.h
treewide: be explicit about dependence on oid-array.h
...
Dozens of files made use of advice functions, without explicitly
including advice.h. This made it more difficult to find which files
could remove a dependence on cache.h. Make C files explicitly include
advice.h if they are using it.
Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Dozens of files made use of trace and trace2 functions, without
explicitly including trace.h or trace2.h. This made it more difficult
to find which files could remove a dependence on cache.h. Make C files
explicitly include trace.h or trace2.h if they are using them.
Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Split key function and data structure definitions out of cache.h to
new header files and adjust the users.
* en/header-split-cleanup:
csum-file.h: remove unnecessary inclusion of cache.h
write-or-die.h: move declarations for write-or-die.c functions from cache.h
treewide: remove cache.h inclusion due to setup.h changes
setup.h: move declarations for setup.c functions from cache.h
treewide: remove cache.h inclusion due to environment.h changes
environment.h: move declarations for environment.c functions from cache.h
treewide: remove unnecessary includes of cache.h
wrapper.h: move declarations for wrapper.c functions from cache.h
path.h: move function declarations for path.c functions from cache.h
cache.h: remove expand_user_path()
abspath.h: move absolute path functions from cache.h
environment: move comment_line_char from cache.h
treewide: remove unnecessary cache.h inclusion from several sources
treewide: remove unnecessary inclusion of gettext.h
treewide: be explicit about dependence on gettext.h
treewide: remove unnecessary cache.h inclusion from a few headers
Code clean-up around the use of the_repository.
* ab/remove-implicit-use-of-the-repository:
libs: use "struct repository *" argument, not "the_repository"
post-cocci: adjust comments for recent repo_* migration
cocci: apply the "revision.h" part of "the_repository.pending"
cocci: apply the "rerere.h" part of "the_repository.pending"
cocci: apply the "refs.h" part of "the_repository.pending"
cocci: apply the "promisor-remote.h" part of "the_repository.pending"
cocci: apply the "packfile.h" part of "the_repository.pending"
cocci: apply the "pretty.h" part of "the_repository.pending"
cocci: apply the "object-store.h" part of "the_repository.pending"
cocci: apply the "diff.h" part of "the_repository.pending"
cocci: apply the "commit.h" part of "the_repository.pending"
cocci: apply the "commit-reach.h" part of "the_repository.pending"
cocci: apply the "cache.h" part of "the_repository.pending"
cocci: add missing "the_repository" macros to "pending"
cocci: sort "the_repository" rules by header
cocci: fix incorrect & verbose "the_repository" rules
cocci: remove dead rule from "the_repository.pending.cocci"
The index files can become corrupt under certain conditions when
the split-index feature is in use, especially together with
fsmonitor, which have been corrected.
* js/split-index-fixes:
unpack-trees: take care to propagate the split-index flag
fsmonitor: avoid overriding `cache_changed` bits
split-index; stop abusing the `base_oid` to strip the "link" extension
split-index & fsmonitor: demonstrate a bug
* ab/remove-implicit-use-of-the-repository:
libs: use "struct repository *" argument, not "the_repository"
post-cocci: adjust comments for recent repo_* migration
cocci: apply the "revision.h" part of "the_repository.pending"
cocci: apply the "rerere.h" part of "the_repository.pending"
cocci: apply the "refs.h" part of "the_repository.pending"
cocci: apply the "promisor-remote.h" part of "the_repository.pending"
cocci: apply the "packfile.h" part of "the_repository.pending"
cocci: apply the "pretty.h" part of "the_repository.pending"
cocci: apply the "object-store.h" part of "the_repository.pending"
cocci: apply the "diff.h" part of "the_repository.pending"
cocci: apply the "commit.h" part of "the_repository.pending"
cocci: apply the "commit-reach.h" part of "the_repository.pending"
cocci: apply the "cache.h" part of "the_repository.pending"
cocci: add missing "the_repository" macros to "pending"
cocci: sort "the_repository" rules by header
cocci: fix incorrect & verbose "the_repository" rules
cocci: remove dead rule from "the_repository.pending.cocci"
Apply the part of "the_repository.pending.cocci" pertaining to
"promisor-remote.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When copying the `split_index` structure from one index structure to
another, we need to propagate the `SPLIT_INDEX_ORDERED` flag, too, if it
is set, otherwise Git might forget to write the shared index when that
is actually needed.
It just so _happens_ that in many instances when `unpack_trees()` is
called, the result causes the shared index to be written anyway, but
there are edge cases when that is not so.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Dozens of files made use of gettext functions, without explicitly
including gettext.h. This made it more difficult to find which files
could remove a dependence on cache.h. Make C files explicitly include
gettext.h if they are using it.
However, while compat/fsmonitor/fsm-ipc-darwin.c should also gain an
include of gettext.h, it was left out to avoid conflicting with an
in-flight topic.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code clean-up to clarify the rule that "git-compat-util.h" must be
the first to be included.
* en/header-cleanup:
diff.h: remove unnecessary include of object.h
Remove unnecessary includes of builtin.h
treewide: replace cache.h with more direct headers, where possible
replace-object.h: move read_replace_refs declaration from cache.h to here
object-store.h: move struct object_info from cache.h
dir.h: refactor to no longer need to include cache.h
object.h: stop depending on cache.h; make cache.h depend on object.h
ident.h: move ident-related declarations out of cache.h
pretty.h: move has_non_ascii() declaration from commit.h
cache.h: remove dependence on hex.h; make other files include it explicitly
hex.h: move some hex-related declarations from cache.h
hash.h: move some oid-related declarations from cache.h
alloc.h: move ALLOC_GROW() functions from cache.h
treewide: remove unnecessary cache.h includes in source files
treewide: remove unnecessary cache.h includes
treewide: remove unnecessary git-compat-util.h includes in headers
treewide: ensure one of the appropriate headers is sourced first
Avoid making users believe they need to initialize df_conflict_entry
to something (as happened with other output only fields before) with
a quick comment and a small sanity check.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/read-tree.c has some special functionality explicitly designed
for debugging unpack-trees.[ch]. Associated with that is two fields
that no other external caller would or should use. Mark these as
internal to unpack-trees, but allow builtin/read-tree to read or write
them for this special case.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous patch made many lines a little longer, resulting in four
becoming a bit too long. They were left as-is for the previous patch
to facilitate reviewers verifying that we were just adding "internal."
in a bunch of places, but rewrap them now.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Continue the work from the previous patch by finding additional fields
which are only used internally but not yet explicitly marked as such,
and include them in the internal fields struct.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This just splits the two fields already marked as internal-only into a
separate internal struct. Future commits will add more fields that
were meant to be internal-only but were not explicitly marked as such
to the same struct.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 2f6b1eb794 ("cache API: add a "INDEX_STATE_INIT" macro/function,
add release_index()", 2023-01-12) mistakenly added some initialization
of a member of unpack_trees_options that was intended to be
internal-only. This initialization should be done within
update_sparsity() instead.
Note that while o->result is mostly meant for unpack_trees() and
update_sparsity() mostly operates without o->result,
check_ok_to_remove() does consult it so we need to ensure it is properly
initialized.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
struct unpack_trees_options has the following field and comment:
struct pattern_list *pl; /* for internal use */
Despite the internal-use comment, commit e091228e17 ("sparse-checkout:
update working directory in-process", 2019-11-21) starting setting this
field from an external caller. At the time, the only way around that
would have been to modify unpack_trees() to take an extra pattern_list
argument, and there's a lot of callers of that function. However, when
we split update_sparsity() off as a separate function, with
sparse-checkout being the sole caller, the need to update other callers
went away. Fix this API problem by adding a pattern_list argument to
update_sparsity() and stop setting the internal o.pl field directly.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The update_sparsity() function was introduced in commit 7af7a25853
("unpack-trees: add a new update_sparsity() function", 2020-03-27).
Prior to that, unpack_trees() was used, but that had a few bugs because
the needs of the caller were different, and different enough that
unpack_trees() could not easily be modified to handle both usecases.
The implementation detail that update_sparsity() was written by copying
unpack_trees() and then streamlining it, and then modifying it in the
needed ways still shows through in that there are leftover vestiges in
both functions that are no longer needed. Clean them up. In
particular:
* update_sparsity() allows a pattern list to be passed in, but
unpack_trees() never should use a different pattern list. Add a
check and a BUG() if this gets violated.
* update_sparsity() has a check early on that will BUG() if
o->skip_sparse_checkout is set; as such, there's no need to check
for that condition again later in the code. We can simply remove
the check and its corresponding goto label.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a directory exists but has only ignored files within it and we are
trying to switch to a branch that has a file where that directory is,
the behavior depends upon --[no]-overwrite-ignore. If the user wants to
--overwrite-ignore (the default), then we should delete the ignored file
and directory and switch to the new branch.
The code to handle this in verify_clean_subdirectory() in unpack-trees
tried to handle this via paying attention to the exclude_per_dir setting
of the internal dir field. This came from commit c81935348b ("Fix
switching to a branch with D/F when current branch has file D.",
2007-03-15), which pre-dated 039bc64e88 ("core.excludesfile clean-up",
2007-11-14), and thus did not pay attention to ignore patterns from
other relevant files. Change it to use setup_standard_excludes() so
that it is also aware of excludes specified in other locations.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the "repo" member was added to "the_index" in [1] the
repo_read_index() was made to populate it, but the unpopulated
"the_index" variable didn't get the same treatment.
Let's do that in initialize_the_repository() when we set it up, and
likewise for all of the current callers initialized an empty "struct
index_state".
This simplifies code that needs to deal with "the_index" or a custom
"struct index_state", we no longer need to second-guess this part of
the "index_state" deep in the stack. A recent example of such
second-guessing is the "istate->repo ? istate->repo : the_repository"
code in [2]. We can now simply use "istate->repo".
We're doing this by making use of the INDEX_STATE_INIT() macro (and
corresponding function) added in [3], which now have mandatory "repo"
arguments.
Because we now call index_state_init() in repository.c's
initialize_the_repository() we don't need to handle the case where we
have a "repo->index" whose "repo" member doesn't match the "repo"
we're setting up, i.e. the "Complete the double-reference" code in
repo_read_index() being altered here. That logic was originally added
in [1], and was working around the lack of what we now have in
initialize_the_repository().
For "fsmonitor-settings.c" we can remove the initialization of a NULL
"r" argument to "the_repository". This was added back in [4], and was
needed at the time for callers that would pass us the "r" from an
"istate->repo". Before this change such a change to
"fsmonitor-settings.c" would segfault all over the test suite (e.g. in
t0002-gitfile.sh).
This change has wider eventual implications for
"fsmonitor-settings.c". The reason the other lazy loading behavior in
it is required (starting with "if (!r->settings.fsmonitor) ..." is
because of the previously passed "r" being "NULL".
I have other local changes on top of this which move its configuration
reading to "prepare_repo_settings()" in "repo-settings.c", as we could
now start to rely on it being called for our "r". But let's leave all
of that for now, and narrowly remove this particular part of the
lazy-loading.
1. 1fd9ae517c (repository: add repo reference to index_state,
2021-01-23)
2. ee1f0c242e (read-cache: add index.skipHash config option,
2023-01-06)
3. 2f6b1eb794 (cache API: add a "INDEX_STATE_INIT" macro/function,
add release_index(), 2023-01-12)
4. 1e0ea5c431 (fsmonitor: config settings are repository-specific,
2022-03-25)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Hopefully in some not so distant future, we'll get advantages from always
initializing the "repo" member of the "struct index_state". To make
that easier let's introduce an initialization macro & function.
The various ad-hoc initialization of the structure can then be changed
over to it, and we can remove the various "0" assignments in
discard_index() in favor of calling index_state_init() at the end.
While not strictly necessary, let's also change the CALLOC_ARRAY() of
various "struct index_state *" to use an ALLOC_ARRAY() followed by
index_state_init() instead.
We're then adding the release_index() function and converting some
callers (including some of these allocations) over to it if they
either won't need to use their "struct index_state" again, or are just
about to call index_state_init().
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make the ensure_full_index() function stricter, and have it only
accept a non-NULL "struct index_state". This function (and this
behavior) was added in [1].
The only reason it needed to be this lax was due to interaction with
repo_index_has_changes(). See the addition of that code in [2].
The other reason for why this was needed dates back to interaction
with code added in [3]. In [4] we started calling ensure_full_index()
in unpack_trees(), but the caller added in 34110cd4e3 wants to pass
us a NULL "dst_index". Let's instead do the NULL check in
unpack_trees() itself.
1. 4300f8442a (sparse-index: implement ensure_full_index(), 2021-03-30)
2. 0c18c059a1 (read-cache: ensure full index, 2021-04-01)
3. 34110cd4e3 (Make 'unpack_trees()' have a separate source and
destination index, 2008-03-06)
4. 6863df3550 (unpack-trees: ensure full index, 2021-03-30)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Stop using "git --super-prefix" and narrow the scope of its use to
the submodule--helper.
* ab/no-more-git-global-super-prefix:
read-tree: add "--super-prefix" option, eliminate global
submodule--helper: convert "{update,clone}" to their own "--super-prefix"
submodule--helper: convert "status" to its own "--super-prefix"
submodule--helper: convert "sync" to its own "--super-prefix"
submodule--helper: convert "foreach" to its own "--super-prefix"
submodule--helper: don't use global --super-prefix in "absorbgitdirs"
submodule.c & submodule--helper: pass along "super_prefix" param
read-tree + fetch tests: test failing "--super-prefix" interaction
submodule absorbgitdirs tests: add missing "Migrating git..." tests
The "--super-prefix" option to "git" was initially added in [1] for
use with "ls-files"[2], and shortly thereafter "submodule--helper"[3]
and "grep"[4]. It wasn't until [5] that "read-tree" made use of it.
At the time [5] made sense, but since then we've made "ls-files"
recurse in-process in [6], "grep" in [7], and finally
"submodule--helper" in the preceding commits.
Let's also remove it from "read-tree", which allows us to remove the
option to "git" itself.
We can do this because the only remaining user of it is the submodule
API, which will now invoke "read-tree" with its new "--super-prefix"
option. It will only do so when the "submodule_move_head()" function
is called.
That "submodule_move_head()" function was then only invoked by
"read-tree" itself, but now rather than setting an environment
variable to pass "--super-prefix" between cmd_read_tree() we:
- Set a new "super_prefix" in "struct unpack_trees_options". The
"super_prefixed()" function in "unpack-trees.c" added in [5] will now
use this, rather than get_super_prefix() looking up the environment
variable we set earlier in the same process.
- Add the same field to the "struct checkout", which is only needed to
ferry the "super_prefix" in the "struct unpack_trees_options" all the
way down to the "entry.c" callers of "submodule_move_head()".
Those calls which used the super prefix all originated in
"cmd_read_tree()". The only other caller is the "unlink_entry()"
caller in "builtin/checkout.c", which now passes a "NULL".
1. 74866d7579 (git: make super-prefix option, 2016-10-07)
2. e77aa336f1 (ls-files: optionally recurse into submodules, 2016-10-07)
3. 89c8626557 (submodule helper: support super prefix, 2016-12-08)
4. 0281e487fd (grep: optionally recurse into submodules, 2016-12-16)
5. 3d415425c7 (unpack-trees: support super-prefix option, 2017-01-17)
6. 188dce131f (ls-files: use repository object, 2017-06-22)
7. f9ee2fcdfa (grep: recurse in-process using 'struct repository', 2017-08-02)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These files are already included; we do not need to include them again
Signed-off-by: Seija Kijin <doremylover123@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add (disabled by default) option to skip the 'cache_tree_update()' at the
end of 'unpack_trees()'. In many cases, this cache tree update is redundant
because the caller of 'unpack_trees()' immediately follows it with
'prime_cache_tree()', rebuilding the entire cache tree from scratch. While
these operations aren't the most expensive part of operations like 'git
reset', the duplicate calls still create a minor unnecessary slowdown.
Introduce an option for callers to skip the 'cache_tree_update()' in
'unpack_trees()' if it is redundant (that is, if 'prime_cache_tree()' is
called afterwards). At the moment, no 'unpack_trees()' callers use the new
option; they will be updated in subsequent patches.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Segfault fix-up to an earlier fix to the topic to teach "git reset"
and "git checkout" work better in a sparse checkout.
* vd/sparse-reset-checkout-fixes:
unpack-trees: fix sparse directory recursion check
Ensure 'is_sparse_directory_entry()' receives a valid 'name_entry *' if one
exists in the list of tree(s) being unpacked in 'unpack_callback()'.
Currently, 'is_sparse_directory_entry()' is called with the first
'name_entry' in the 'names' list of entries on 'unpack_callback()'. However,
this entry may be empty even when other elements of 'names' are not (such as
when switching from an orphan branch back to a "normal" branch). As a
result, 'is_sparse_directory_entry()' could incorrectly indicate that a
sparse directory is *not* actually sparse because the name of the index
entry does not match the (empty) 'name_entry' path.
Fix the issue by using the existing 'name_entry *p' value in
'unpack_callback()', which points to the first non-empty entry in 'names'.
Because 'p' is 'const', also update 'is_sparse_directory_entry()'s
'name_entry *' argument to be 'const'.
Finally, add a regression test case.
Reported-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fixes to sparse index compatibility work for "reset" and "checkout"
commands.
source: <pull.1312.v3.git.1659985672.gitgitgadget@gmail.com>
* vd/sparse-reset-checkout-fixes:
unpack-trees: unpack new trees as sparse directories
cache.h: create 'index_name_pos_sparse()'
oneway_diff: handle removed sparse directories
checkout: fix nested sparse directory diff in sparse index
Fixes to sparse index compatibility work for "reset" and "checkout"
commands.
* vd/sparse-reset-checkout-fixes:
unpack-trees: unpack new trees as sparse directories
cache.h: create 'index_name_pos_sparse()'
oneway_diff: handle removed sparse directories
checkout: fix nested sparse directory diff in sparse index
If 'unpack_single_entry()' is unpacking a new directory tree (that is, one
not already present in the index) into a sparse index, unpack the tree as a
sparse directory rather than traversing its contents and unpacking each file
individually. This helps keep the sparse index as collapsed as possible in
cases such as 'git reset --hard' restoring a outside-of-cone directory
removed with 'git rm -r --sparse'.
Without this patch, 'unpack_single_entry()' will only unpack a directory
into the index as a sparse directory (rather than traversing into it and
unpacking its files one-by-one) if an entry with the same name already
exists in the index. This patch allows sparse directory unpacking without a
matching index entry when the following conditions are met:
1. the directory's path is outside the sparse cone, and
2. there are no children of the directory in the index
If a directory meets these requirements (as determined by
'is_new_sparse_dir()'), 'unpack_single_entry()' unpacks the sparse directory
index entry and propagates the decision back up to 'unpack_callback()' to
prevent unnecessary tree traversal into the unpacked directory.
Reported-by: Shaoxuan Yuan <shaoxuan.yuan02@gmail.com>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
At the end of `git checkout <pathspec>`, we get a message informing how
many entries were updated in the working tree. However, this number can
be inaccurate for two reasons:
1) Delayed entries currently get counted twice.
2) Failed entries are included in the count.
The first problem happens because the counter is first incremented
before inserting the entry in the delayed checkout queue, and once again
when finish_delayed_checkout() calls checkout_entry(). And the second
happens because the counter is incremented too early in
checkout_entry(), before the entry was in fact checked out. Fix that by
moving the count increment further down in the call stack and removing
the duplicate increment on delayed entries. Note that we have to keep
a per-entry reference for the counter (both on parallel checkout and
delayed checkout) because not all entries are always accumulated at the
same counter. See checkout_worktree(), at builtin/checkout.c for an
example.
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More fsmonitor--daemon.
* jh/builtin-fsmonitor-part3: (30 commits)
t7527: improve implicit shutdown testing in fsmonitor--daemon
fsmonitor--daemon: allow --super-prefix argument
t7527: test Unicode NFC/NFD handling on MacOS
t/lib-unicode-nfc-nfd: helper prereqs for testing unicode nfc/nfd
t/helper/hexdump: add helper to print hexdump of stdin
fsmonitor: on macOS also emit NFC spelling for NFD pathname
t7527: test FSMonitor on case insensitive+preserving file system
fsmonitor: never set CE_FSMONITOR_VALID on submodules
t/perf/p7527: add perf test for builtin FSMonitor
t7527: FSMonitor tests for directory moves
fsmonitor: optimize processing of directory events
fsm-listen-darwin: shutdown daemon if worktree root is moved/renamed
fsm-health-win32: force shutdown daemon if worktree root moves
fsm-health-win32: add polling framework to monitor daemon health
fsmonitor--daemon: stub in health thread
fsmonitor--daemon: rename listener thread related variables
fsmonitor--daemon: prepare for adding health thread
fsmonitor--daemon: cd out of worktree root
fsm-listen-darwin: ignore FSEvents caused by xattr changes on macOS
unpack-trees: initialize fsmonitor_has_run_once in o->result
...
"sparse-checkout" learns to work well with the sparse-index
feature.
* ds/sparse-sparse-checkout:
sparse-checkout: integrate with sparse index
p2000: add test for 'git sparse-checkout [add|set]'
sparse-index: complete partial expansion
sparse-index: partially expand directories
sparse-checkout: --no-sparse-index needs a full index
cache-tree: implement cache_tree_find_path()
sparse-index: introduce partially-sparse indexes
sparse-index: create expand_index()
t1092: stress test 'git sparse-checkout set'
t1092: refactor 'sparse-index contents' test
Initialize `o->result.fsmonitor_has_run_once` based upon value
in `o->src_index->fsmonitor_has_run_once` to prevent a second
fsmonitor query during the tree traversal and possibly getting
a skewed view of the working directory.
The checkout code has already talked to the fsmonitor and the
traversal is updating the index as it traverses, so there is
no need to query the fsmonitor.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When modifying the sparse-checkout definition, the sparse-checkout
builtin calls update_sparsity() to modify the SKIP_WORKTREE bits of all
cache entries in the index. Before, we needed the index to be fully
expanded in order to ensure we had the full list of files necessary that
match the new patterns.
Insert a call to reset_sparse_directories() that expands sparse
directories that are within the new pattern list, but only far enough
that every necessary file path now exists as a cache entry. The
remaining logic within update_sparsity() will modify the SKIP_WORKTREE
bits appropriately.
This allows us to disable command_requires_full_index within the
sparse-checkout builtin. Add tests that demonstrate that we are not
expanding to a full index unnecessarily.
We can see the improved performance in the p2000 test script:
Test HEAD~1 HEAD
------------------------------------------------------------------------
2000.24: git ... (sparse-v3) 2.14(1.55+0.58) 1.57(1.03+0.53) -26.6%
2000.25: git ... (sparse-v4) 2.20(1.62+0.57) 1.58(0.98+0.59) -28.2%
These reductions of 26-28% are small compared to most examples, but the
time is dominated by writing a new copy of the base repository to the
worktree and then deleting it again. The fact that the previous index
expansion was such a large portion of the time is telling how important
it is to complete this sparse index integration.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When unpacking trees, set the default sparsity of the resultant index based
on repo settings and 'is_sparse_index_allowed()'.
Normally, when executing 'unpack_trees', the output index is marked sparse
when (and only when) it unpacks a sparse directory. However, an index may be
"sparse" even if it contains no sparse directories - when all files fall
inside the sparse-checkout definition or otherwise have SKIP_WORKTREE
disabled. Therefore, the output index may be marked "full" even when it is
"sparse", resulting in unnecessary 'ensure_full_index' calls when writing to
disk. Avoid this by setting the "default" index sparsity to match what is
expected for the repository.
As a consequence of this fix, the (non-merge) 'read-tree' performed when
applying a stash with untracked files no longer expands the index. Update
the corresponding test in 't1092'.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This reverts commit f2a454e0a5 (unpack-trees: improve performance of
next_cache_entry, 2021-11-29).
The "hint" value was originally needed to improve performance in 'git reset
-- <pathspec>' caused by 'cache_bottom' lagging behind its correct value
when using a sparse index. The 'cache_bottom' tracking has since been
corrected, removing the need for an additional "pseudo-cache_bottom"
tracking variable.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Correct tracking of the 'cache_bottom' for cases where sparse directories
are present in the index.
BACKGROUND
----------
The 'unpack_trees_options.cache_bottom' is a variable that tracks the
in-progress "bottom" of the cache as 'unpack_trees()' iterates through the
contents of the index. Most importantly, this value informs the sequential
return values of 'next_cache_entry()' which, in the "diff cache" usage of
'unpack_callback()', are either unpacked as-is or are passed into the diff
machinery.
The 'cache_bottom' is intended to track the position of the first entry in
the index that has not yet been diffed or unpacked. It is advanced in two
main ways: either it is incremented when an index entry is marked as "used"
(in 'mark_ce_used()'), indicating that it was unpacked or diffed, or when a
directory is unpacked, in which case it is increased by an amount equaling
the number of index entries inside that tree.
In 17a1bb570b (unpack-trees: preserve cache_bottom, 2021-07-14), it was
identified that sparse directories posed a problem to the above
'cache_bottom' advancement logic - because a sparse directory was both an
index entry that could be "used" and a directory that can be unpacked, the
'cache_bottom' would be incremented too many times. To solve this problem,
the 'mark_ce_used()' advancement of 'cache_bottom' was skipped for sparse
directories.
INCORRECT CACHE_BOTTOM TRACKING
-------------------------------
Skipping the 'cache_bottom' advancement for sparse directories in
'mark_ce_used()' breaks down in two cases:
1. When the 'unpack_trees()' operation is *not* a "cache diff" (because the
directory contents-based incrementing of 'cache_bottom' does not happen).
2. When a cache diff is performed with a pathspec (because
'unpack_index_entry()' will unpack a sparse directory not matched by the
pathspec without performing the directory contents-based increment).
The former luckily does not appear to affect 'git' behavior, likely because
'cache_bottom' is largely unused (non-"cache diff" 'unpack_trees()' uses
'find_index_entry()' - rather than 'next_cache_entry()' - to find the index
entries to unpack).
The latter, however, causes 'cache_bottom' to "lag behind" its intended
position by an amount equal to the number of sparse directories unpacked so
far with 'unpack_index_entry()'. If a repository is structured such that any
sparse directories are ordered lexicographically *after* any
pathspec-matching directories, though, this issue won't present any adverse
behavior.
This was the case with the 't1092-sparse-checkout-compatibility.sh' tests
before the addition of the 'before/' sparse directory (ordered *before* the
in-cone 'deep/' directory), therefore sidestepping the issue. Once the
'before/' directory was added, though, 'cache_bottom' began to lag behind
its intended position, causing 'next_cache_entry()' to return index entries
it had already processed and, ultimately, an incorrect diff.
CORRECTING CACHE_BOTTOM
-----------------------
The problems observed in 't1092' come from 'cache_bottom' lagging behind in
cases where the cache tree-based advancement doesn't occur. To solve this,
then, the fix in 17a1bb570b is "reversed"; rather than skipping
'cache_bottom' advancement in 'mark_ce_used()', we skip the directory
contents-based advancement for sparse directories. Now, every index entry
can be accounted for in 'cache_bottom':
* if you're working with a single index entry, 'cache_bottom' is incremented
in 'mark_ce_used()'
* if you're working with a directory that contains index entries (but is not
one itself), 'cache_bottom' is incremented by the number of entries in
that directory.
Finally, change the 'test_expect_failure' tests in 't1092' failing due to
this bug back to 'test_expect_success'.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
