Most of the functions in "refs.h" have two flavors: one that accepts a
`struct ref_store`, and one that figures it out via `the_repository`.
As part of the libification efforts we want to get rid of the latter
variant and stop relying on `the_repository` altogether.
Introduce a set of Coccinelle rules that transform callers of the "refs"
interfaces to pass a `struct ref_store`. These rules are not yet applied
by this patch so that it can be reviewed standalone more easily. This
will be done in the next patch.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add and apply a semantic patch for calling xstrncmpz() to compare a
NUL-terminated string with a buffer of a known length instead of using
strncmp() and checking the terminating NUL explicitly. This simplifies
callers by reducing code duplication.
I had to adjust remote.c manually because Coccinelle inexplicably
changed the indent of the else branches.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Plumb "struct key_value_info" through all code paths that end in
die_bad_number(), which lets us remove the helper functions that read
analogous values from "struct config_reader". As a result, nothing reads
config_reader.config_kvi any more, so remove that too.
In config.c, this requires changing the signature of
git_configset_get_value() to 'return' "kvi" in an out parameter so that
git_configset_get_<type>() can pass it to git_config_<type>(). Only
numeric types will use "kvi", so for non-numeric types (e.g.
git_configset_get_string()), pass NULL to indicate that the out
parameter isn't needed.
Outside of config.c, config callbacks now need to pass "ctx->kvi" to any
of the git_config_<type>() functions that parse a config string into a
number type. Included is a .cocci patch to make that refactor.
The only exceptional case is builtin/config.c, where git_config_<type>()
is called outside of a config callback (namely, on user-provided input),
so config source information has never been available. In this case,
die_bad_number() defaults to a generic, but perfectly descriptive
message. Let's provide a safe, non-NULL for "kvi" anyway, but make sure
not to change the message.
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a new "const struct config_context *ctx" arg to config_fn_t to hold
additional information about the config iteration operation.
config_context has a "struct key_value_info kvi" member that holds
metadata about the config source being read (e.g. what kind of config
source it is, the filename, etc). In this series, we're only interested
in .kvi, so we could have just used "struct key_value_info" as an arg,
but config_context makes it possible to add/adjust members in the future
without changing the config_fn_t signature. We could also consider other
ways of organizing the args (e.g. moving the config name and value into
config_context or key_value_info), but in my experiments, the
incremental benefit doesn't justify the added complexity (e.g. a
config_fn_t will sometimes invoke another config_fn_t but with a
different config value).
In subsequent commits, the .kvi member will replace the global "struct
config_reader" in config.c, making config iteration a global-free
operation. It requires much more work for the machinery to provide
meaningful values of .kvi, so for now, merely change the signature and
call sites, pass NULL as a placeholder value, and don't rely on the arg
in any meaningful way.
Most of the changes are performed by
contrib/coccinelle/config_fn_ctx.pending.cocci, which, for every
config_fn_t:
- Modifies the signature to accept "const struct config_context *ctx"
- Passes "ctx" to any inner config_fn_t, if needed
- Adds UNUSED attributes to "ctx", if needed
Most config_fn_t instances are easily identified by seeing if they are
called by the various config functions. Most of the remaining ones are
manually named in the .cocci patch. Manual cleanups are still needed,
but the majority of it is trivial; it's either adjusting config_fn_t
that the .cocci patch didn't catch, or adding forward declarations of
"struct config_context ctx" to make the signatures make sense.
The non-trivial changes are in cases where we are invoking a config_fn_t
outside of config machinery, and we now need to decide what value of
"ctx" to pass. These cases are:
- trace2/tr2_cfg.c:tr2_cfg_set_fl()
This is indirectly called by git_config_set() so that the trace2
machinery can notice the new config values and update its settings
using the tr2 config parsing function, i.e. tr2_cfg_cb().
- builtin/checkout.c:checkout_main()
This calls git_xmerge_config() as a shorthand for parsing a CLI arg.
This might be worth refactoring away in the future, since
git_xmerge_config() can call git_default_config(), which can do much
more than just parsing.
Handle them by creating a KVI_INIT macro that initializes "struct
key_value_info" to a reasonable default, and use that to construct the
"ctx" arg.
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These practices largely reflect what we are already doing on the mailing
list, which should help new Coccinelle authors and reviewers get up to
speed.
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
- Drop "examples" since we actually use the patches.
- Drop sentences that could be headings instead
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When 'unused.cocci' was added in 4f40f6cb73 (cocci: add and apply a
rule to find "unused" strbufs, 2022-07-05) it found three unused
strbufs, and when it was generalized in the next commit it managed to
find an unused string_list as well. That's four unused variables in
over 17 years, so apparently we rarely make this mistake.
Unfortunately, applying 'unused.cocci' is quite expensive, e.g. it
increases the from-scratch runtime of 'make coccicheck' by over 5:30
minutes or over 160%:
$ make -s cocciclean
$ time make -s coccicheck
* new spatch flags
real 8m56.201s
user 0m0.420s
sys 0m0.406s
$ rm contrib/coccinelle/unused.cocci contrib/coccinelle/tests/unused.*
$ make -s cocciclean
$ time make -s coccicheck
* new spatch flags
real 3m23.893s
user 0m0.228s
sys 0m0.247s
That's a lot of runtime spent for not much in return, and arguably an
unused struct instance sneaking in is not that big of a deal to
justify the significantly increased runtime.
Remove 'unused.cocci', because we are not getting our CPU cycles'
worth.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"revision.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"rerere.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"refs.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
Apply the part of "the_repository.pending.cocci" pertaining to
"packfile.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"pretty.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"object-store.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"diff.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"commit.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"commit-reach.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"cache.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the case of diff.h, rerere.h and revision.h the macros were added
in [1], [2] and [3] when "the_repository.pending.cocci" didn't
exist. None of the subsequently added migration rules covered
them. Let's add those missing rules.
In the case of macros in "cache.h", "commit.h", "packfile.h",
"promisor-remote.h" and "refs.h" those aren't guarded by
"NO_THE_REPOSITORY_COMPATIBILITY_MACROS", but they're also macros that
add "the_repository" as the first argument, so we should migrate away
from them.
1. 2abf350385 (revision.c: remove implicit dependency on the_index,
2018-09-21)
2. e675765235 (diff.c: remove implicit dependency on the_index,
2018-09-21)
3. 35843b1123 (rerere.c: remove implicit dependency on the_index,
2018-09-21)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Sort the "the_repository.pending.cocci" file by which header the
macros are in, and add a comment to that effect in front of the
rules. This will make subsequent commits easier to follow, as we'll be
applying these rules on a header-by-header basis.
Once we've fully applied "the_repository.pending.cocci" we'll keep
this rules around for a while in "the_repository.cocci", to help any
outstanding topics and out-of-tree code to resolve textual or semantic
conflicts with these changes, but eventually we'll remove the
"the_repository.cocci" as a follow-up.
So even if some of these functions are subsequently moved and/or split
into other or new headers there's no risk of this becoming stale, if
and when that happens the we should be removing these rules anyway.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When these rules started being added in [1] they didn't use a ";"
after the ")", and would thus catch uses of these macros within
expressions. But as of [2] the new additions were broken in that
they'd only match a subset of the users of these macros.
Rather than narrowly fixing that, let's have these use the much less
verbose pattern introduced in my recent [3]: There's no need to
exhaustively enumerate arguments if we use the "..." syntax. This
means that we can fold all of these different rules into one.
1. afd69dcc21 (object-store: prepare read_object_file to deal with
any repo, 2018-11-13)
2. 21a9651ba3 (commit-reach: prepare get_merge_bases to handle any
repo, 2018-11-13)
3. 0e6550a2c6 (cocci: add a index-compatibility.pending.cocci,
2022-11-19)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "parse_commit_gently" macro went away in [1], so we don't need to
carry this for its migration.
1. ea3f7e598c (revision: use repository from rev_info when parsing
commits, 2020-06-23)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Have the last users of "USE_THE_INDEX_COMPATIBILITY_MACROS" use the
underlying *_index() variants instead. Now all previous users of
"USE_THE_INDEX_COMPATIBILITY_MACROS" have been migrated away from the
wrapper macros, and if applicable to use the "USE_THE_INDEX_VARIABLE"
added in [1].
Let's leave the "index-compatibility.cocci" in place, even though it
won't be doing anything on "master". It will benefit any out-of-tree
code that need to use these compatibility macros. We can eventually
remove it.
1. bdafeae0b9 (cache.h & test-tool.h: add & use
"USE_THE_INDEX_VARIABLE", 2022-11-19)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove the redundant update_main_cache_tree() function, and make its
users use cache_tree_update() instead.
The behavior of populating the "the_index.cache_tree" if it wasn't
present already was needed when this function was introduced in [1],
but it hasn't been needed since [2]; The "cache_tree_update()" will
now lazy-allocate, so there's no need for the wrapper.
1. 996277c520 (Refactor cache_tree_update idiom from commit,
2011-12-06)
2. fb0882648e (cache-tree: clean up cache_tree_update(), 2021-01-23)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a trivial rule for "write_cache_as_tree" to
"index-compatibility.cocci", and apply it. This was left out of the
rules added in 0e6550a2c6 (cocci: add a
index-compatibility.pending.cocci, 2022-11-19) because this
compatibility wrapper lived in "cache-tree.h", not "cache.h"
But it's like the other "USE_THE_INDEX_COMPATIBILITY_MACROS", so let's
migrate it too.
The replacement of "USE_THE_INDEX_COMPATIBILITY_MACROS" here with
"USE_THE_INDEX_VARIABLE" is a manual change on top, now that these
files only use "&the_index", and don't need any compatibility
macros (or functions).
The wrapping of some argument lists is likewise manual, as coccinelle
would otherwise give us overly long argument lists.
The reason for putting the "O" in the cocci rule on the "-" and "+"
lines is because I couldn't get correct whitespacing otherwise,
i.e. I'd end up with "oid,&the_index", not "oid, &the_index".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the rule added in [1] to change "cache_name_pos" to
"index_name_pos", which allows us to get rid of another
"USE_THE_INDEX_COMPATIBILITY_MACROS" macro.
The replacement of "USE_THE_INDEX_COMPATIBILITY_MACROS" here with
"USE_THE_INDEX_VARIABLE" is a manual change on top, now that these
files only use "&the_index", and don't need any compatibility
macros (or functions).
1. 0e6550a2c6 (cocci: add a index-compatibility.pending.cocci,
2022-11-19)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the "active_nr" part of "index-compatibility.pending.cocci",
which was left out in [1] due to an in-flight conflict. As of [2] the
topic we conflicted with has been merged to "master", so we can fully
apply this rule.
1. dc594180d9 (cocci & cache.h: apply variable section of "pending"
index-compatibility, 2022-11-19)
2. 9ea1378d04 (Merge branch 'ab/various-leak-fixes', 2022-12-14)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a semantic patch for replace ALLOC_ARRAY+COPY_ARRAY with DUP_ARRAY
to reduce code duplication and apply its results.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since [1] running "make coccicheck" has resulted in [2] being emitted
to the *.log files for the "spatch" run, and in the case of "make
coccicheck-test" we'd emit these to the user's terminal.
Nothing was broken as a result, but let's refactor the relevant rules
to eliminate the ambiguity between a possible variable and an
identifier.
1. 0e6550a2c6 (cocci: add a index-compatibility.pending.cocci,
2022-11-19)
2. warning: line 257: should active_cache be a metavariable?
warning: line 260: should active_cache_changed be a metavariable?
warning: line 263: should active_cache_tree be a metavariable?
warning: line 271: should active_nr be a metavariable?
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply "index-compatibility.pending.cocci" rule to "builtin/*", but
exclude those where we conflict with in-flight changes.
As a result some of them end up using only "the_index", so let's have
them use the more narrow "USE_THE_INDEX_VARIABLE" rather than
"USE_THE_INDEX_COMPATIBILITY_MACROS".
Manual changes not made by coccinelle, that were squashed in:
* Whitespace-wrap argument lists for repo_hold_locked_index(),
repo_read_index_preload() and repo_refresh_and_write_index(), in cases
where the line became too long after the transformation.
* Change "refresh_cache()" to "refresh_index()" in a comment in
"builtin/update-index.c".
* For those whose call was followed by perror("<macro-name>"), change
it to perror("<function-name>"), referring to the new function.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Mostly apply the part of "index-compatibility.pending.cocci" that
renames the global variables like "active_nr", which are a shorthand
to referencing (in that case) a struct member as "the_index.cache_nr".
In doing so move more of "index-compatibility.pending.cocci" to
"index-compatibility.cocci".
In the case of "active_nr" we'd have a textual conflict with
"ab/various-leak-fixes" in "next"[1]. Let's exclude that specific case
while moving the rule over from "pending".
1. 407b94280f (commit: discard partial cache before (re-)reading it,
2022-11-08)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply a selection of rules in "index-compatibility.pending.cocci"
tree-wide, and in doing so migrate them to
"index-compatibility.cocci".
As in preceding commits the only manual changes here are the macro
removals in "cache.h", and the update to the '*.cocci" rules. The rest
of the C code changes are the result of applying those updated rules.
Move rules for some rarely used cache compatibility macros from
"index-compatibility.pending.cocci" to "index-compatibility.cocci" and
apply them.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a coccinelle rule which covers the rest of the macros guarded by
"USE_THE_INDEX_COMPATIBILITY_MACROS" cache.h. If the result of this
were applied it can be reduced down to just:
#ifdef USE_THE_INDEX_COMPATIBILITY_MACROS
extern struct index_state the_index;
#endif
But that patch is just under 2000 lines, so let's first add this as a
"pending", and then incrementally pick changes from it in subsequent
commits. In doing that we'll migrate rules from this
"index-compatibility.pending.cocci" to the "index-compatibility.cocci"
created in a preceding commit.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 4aab5b46f4 (Make read-cache.c "the_index" free., 2007-04-01)
we've been undergoing a slow migration away from these macros, but
haven't made much progress since f8adbec9fe (cache.h: flip
NO_THE_INDEX_COMPATIBILITY_MACROS switch, 2019-01-24).
Let's move forward a bit by changing the users of those macros that
are rare enough that we can convert them in one go, and then remove
the compatibility shim.
The only manual change to the C code here is to "cache.h", the rest is
all the result of applying the new "index-compatibility.cocci".
Even though it's a one-off, let's keep the coccinelle rules for
now. We'll extend them in subsequent commits, and this will help
anything that's in-flight or out-of-tree to migrate.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a rather trivial "spatchcache", with this running e.g.:
make cocciclean
make contrib/coccinelle/free.cocci.patch \
SPATCH=contrib/coccicheck/spatchcache \
SPATCH_FLAGS=--very-quiet
Is cut down from ~20s to ~5s on my system. Much of that is either
fixable shell overhead, or the around 40 files we "CANTCACHE" (see the
implementation).
This uses "redis" as a cache by default, but it's configurable. See
the embedded documentation.
This is *not* like ccache in that we won't cache failed spatch
invocations, or those where spatch suggests changes for us. Those
cases are so rare that I didn't think it was worth the bother, by far
the most common case is that it has no suggested changes. We'll also
refuse to cache any "spatch" invocation that has output on stderr,
which means that "--very-quiet" must be added to "SPATCH_FLAGS".
Because we narrow the cache to that we don't need to save away stdout,
stderr & the exit code. We simply cache the cases where we had no
suggested changes.
Another benchmark is to compare this with the previous
SPATCH_BATCH_SIZE=N, as noted in [1]. Before this (on my 8 core system) running:
make clean; time make contrib/coccinelle/array.cocci.patch SPATCH_BATCH_SIZE=0
Would take 33s, but with the preceding changes running without this
"spatchcache" is slightly slower, or around 35s:
make clean; time make contrib/coccinelle/array.cocci.patch
Now doing the same with SPATCH=contrib/coccinelle/spatchcache will
take around 6s, but we'll need to compile the *.o files first to take
full advantage of it (which can be fast with "ccache"):
make clean; make; time make contrib/coccinelle/array.cocci.patch SPATCH=contrib/coccinelle/spatchcache
1. https://lore.kernel.org/git/YwdRqP1CyUAzCEn2@coredump.intra.peff.net/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
The preceding commits to make the "coccicheck" target incremental made
it slower in some cases. As an optimization let's not have the
many=many mapping of <*.cocci>=<*.[ch]>, but instead concat the
<*.cocci> into an ALL.cocci, and then run one-to-many
ALL.cocci=<*.[ch]>.
A "make coccicheck" is now around 2x as fast as it was on "master",
and around 1.5x as fast as the preceding change to make the run
incremental:
$ git hyperfine -L rev origin/master,HEAD~,HEAD -p 'make clean' 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' -r 3
Benchmark 1: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'origin/master
Time (mean ± σ): 4.258 s ± 0.015 s [User: 27.432 s, System: 1.532 s]
Range (min … max): 4.241 s … 4.268 s 3 runs
Benchmark 2: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD~
Time (mean ± σ): 5.365 s ± 0.079 s [User: 36.899 s, System: 1.810 s]
Range (min … max): 5.281 s … 5.436 s 3 runs
Benchmark 3: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD
Time (mean ± σ): 2.725 s ± 0.063 s [User: 14.796 s, System: 0.233 s]
Range (min … max): 2.667 s … 2.792 s 3 runs
Summary
'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD' ran
1.56 ± 0.04 times faster than 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'origin/master'
1.97 ± 0.05 times faster than 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD~'
This can be turned off with SPATCH_CONCAT_COCCI, but as the
beneficiaries of "SPATCH_CONCAT_COCCI=" would mainly be those
developing the *.cocci rules themselves, let's leave this optimization
on by default.
For more information see my "Optimizing *.cocci rules by concat'ing
them" (<220901.8635dbjfko.gmgdl@evledraar.gmail.com>) on the
cocci@inria.fr mailing list.
This potentially changes the results of our *.cocci rules, but as
noted in that discussion it should be safe for our use. We don't name
rules, or if we do their names don't conflict across our *.cocci
files.
To the extent that we'd have any inter-dependencies between rules this
doesn't make that worse, as we'd have them now if we ran "make
coccicheck", applied the results, and would then have (due to
hypothetical interdependencies) suggested changes on the subsequent
"make coccicheck".
Our "coccicheck-test" target makes use of the ALL.cocci when running
tests, e.g. when testing unused.{c,out} we test it against ALL.cocci,
not unused.cocci. We thus assert (to the extent that we have test
coverage) that this concatenation doesn't change the expected results
of running these rules.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
The <id> in the <rulename> part of the coccinelle syntax[1] is for our
purposes there to declares if we have inter-dependencies between
different rules.
But such <id>'s must be unique within a given semantic patch file. As
we'll be processing a concatenated version of our rules in the
subsequent commit let's remove these names. They weren't being used
for the semantic patches themselves, and equated to a short comment
about the rule.
Both the filename and context of the rules makes it clear what they're
doing, so we're not gaining anything from keeping these. Retaining
them goes against recommendations that "contrib/coccinelle/README"
will be making in the subsequent commit.
This leaves only one named rule in our sources, where it's needed for
a "<id> <-> <extends> <id>" relationship:
$ git -P grep '^@ ' -- contrib/coccinelle/
contrib/coccinelle/swap.cocci:@ swap @
contrib/coccinelle/swap.cocci:@ extends swap @
1. https://coccinelle.gitlabpages.inria.fr/website/docs/main_grammar.html
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Improve the incremental rebuilding support of "coccicheck" by
piggy-backing on the computed dependency information of the
corresponding *.o file, rather than rebuilding all <RULE>/<FILE> pairs
if either their corresponding file changes, or if any header changes.
This in effect uses the same method that the "sparse" target was made
to use in c234e8a0ec (Makefile: make the "sparse" target non-.PHONY,
2021-09-23), except that the dependency on the *.o file isn't a hard
one, we check with $(wildcard) if the *.o file exists, and if so we'll
depend on it.
This means that the common case of:
make
make coccicheck
Will benefit from incremental rebuilding, now changing e.g. a header
will only re-run "spatch" on those those *.c files that make use of
it:
By depending on the *.o we piggy-back on
COMPUTE_HEADER_DEPENDENCIES. See c234e8a0ec (Makefile: make the
"sparse" target non-.PHONY, 2021-09-23) for prior art of doing that
for the *.sp files. E.g.:
make contrib/coccinelle/free.cocci.patch
make -W column.h contrib/coccinelle/free.cocci.patch
Will take around 15 seconds for the second command on my 8 core box if
I didn't run "make" beforehand to create the *.o files. But around 2
seconds if I did and we have those "*.o" files.
Notes about the approach of piggy-backing on *.o for dependencies:
* It *is* a trade-off since we'll pay the extra cost of running the C
compiler, but we're probably doing that anyway. The compiler is much
faster than "spatch", so even though we need to re-compile the *.o to
create the dependency info for the *.c for "spatch" it's
faster (especially if using "ccache").
* There *are* use-cases where some would like to have *.o files
around, but to have the "make coccicheck" ignore them. See:
https://lore.kernel.org/git/20220826104312.GJ1735@szeder.dev/
For those users a:
make
make coccicheck SPATCH_USE_O_DEPENDENCIES=
Will avoid considering the *.o files.
* If that *.o file doesn't exist we'll depend on an intermediate file
of ours which in turn depends on $(FOUND_H_SOURCES).
This covers both an initial build, or where "coccicheck" is run
without running "all" beforehand, and because we run "coccicheck"
on e.g. files in compat/* that we don't know how to build unless
the requisite flag was provided to the Makefile.
Most of the runtime of "incremental" runs is now spent on various
compat/* files, i.e. we conditionally add files to COMPAT_OBJS, and
therefore conflate whether we *can* compile an object and generate
dependency information for it with whether we'd like to link it
into our binary.
Before this change the distinction didn't matter, but now one way
to make this even faster on incremental builds would be to peel
those concerns apart so that we can see that e.g. compat/mmap.c
doesn't depend on column.h.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Optimize the very slow "coccicheck" target to take advantage of
incremental rebuilding, and fix outstanding dependency problems with
the existing rule.
The rule is now faster both on the initial run as we can make better
use of GNU make's parallelism than the old ad-hoc combination of
make's parallelism combined with $(SPATCH_BATCH_SIZE) and/or the
"--jobs" argument to "spatch(1)".
It also makes us *much* faster when incrementally building, it's now
viable to "make coccicheck" as topic branches are merged down.
The rule didn't use FORCE (or its equivalents) before, so a:
make coccicheck
make coccicheck
Would report nothing to do on the second iteration. But all of our
patch output depended on all $(COCCI_SOURCES) files, therefore e.g.:
make -W grep.c coccicheck
Would do a full re-run, i.e. a a change in a single file would force
us to do a full re-run.
The reason for this (not the initial rationale, but my analysis) is:
* Since we create a single "*.cocci.patch+" we don't know where to
pick up where we left off, or how to incrementally merge e.g. a
"grep.c" change with an existing *.cocci.patch.
* We've been carrying forward the dependency on the *.c files since
63f0a758a0 (add coccicheck make target, 2016-09-15) the rule was
initially added as a sort of poor man's dependency discovery.
As we don't include other *.c files depending on other *.c files
has always been broken, as could be trivially demonstrated
e.g. with:
make coccicheck
make -W strbuf.h coccicheck
However, depending on the corresponding *.c files has been doing
something, namely that *if* an API change modified both *.c and *.h
files we'd catch the change to the *.h we care about via the *.c
being changed.
For API changes that happened only via *.h files we'd do the wrong
thing before this change, but e.g. for function additions (not
"static inline" ones) catch the *.h change by proxy.
Now we'll instead:
* Create a <RULE>/<FILE> pair in the .build directory, E.g. for
swap.cocci and grep.c we'll create
.build/contrib/coccinelle/swap.cocci.patch/grep.c.
That file is the diff we'll apply for that <RULE>-<FILE>
combination, if there's no changes to me made (the common case)
it'll be an empty file.
* Our generated *.patch
file (e.g. contrib/coccinelle/swap.cocci.patch) is now a simple "cat
$^" of all of all of the <RULE>/<FILE> files for a given <RULE>.
In the case discussed above of "grep.c" being changed we'll do the
full "cat" every time, so they resulting *.cocci.patch will always
be correct and up-to-date, even if it's "incrementally updated".
See 1cc0425a27 (Makefile: have "make pot" not "reset --hard",
2022-05-26) for another recent rule that used that technique.
As before we'll:
* End up generating a contrib/coccinelle/swap.cocci.patch, if we
"fail" by creating a non-empty patch we'll still exit with a zero
exit code.
Arguably we should move to a more Makefile-native way of doing
this, i.e. fail early, and if we want all of the "failed" changes
we can use "make -k", but as the current
"ci/run-static-analysis.sh" expects us to behave this way let's
keep the existing behavior of exhaustively discovering all cocci
changes, and only failing if spatch itself errors out.
Further implementation details & notes:
* Before this change running "make coccicheck" would by default end
up pegging just one CPU at the very end for a while, usually as
we'd finish whichever *.cocci rule was the most expensive.
This could be mitigated by combining "make -jN" with
SPATCH_BATCH_SIZE, see 960154b9c1 (coccicheck: optionally batch
spatch invocations, 2019-05-06).
There will be cases where getting rid of "SPATCH_BATCH_SIZE" makes
things worse, but a from-scratch "make coccicheck" with the default
of SPATCH_BATCH_SIZE=1 (and tweaking it doesn't make a difference)
is faster (~3m36s v.s. ~3m56s) with this approach, as we can feed
the CPU more work in a less staggered way.
* Getting rid of "SPATCH_BATCH_SIZE" particularly helps in cases
where the default of 1 yields parallelism under "make coccicheck",
but then running e.g.:
make -W contrib/coccinelle/swap.cocci coccicheck
I.e. before that would use only one CPU core, until the user
remembered to adjust "SPATCH_BATCH_SIZE" differently than the
setting that makes sense when doing a non-incremental run of "make
coccicheck".
* Before the "make coccicheck" rule would have to clean
"contrib/coccinelle/*.cocci.patch*", since we'd create "*+" and
"*.log" files there. Now those are created in
.build/contrib/coccinelle/, which is covered by the "cocciclean" rule
already.
Outstanding issues & future work:
* We could get rid of "--all-includes" in favor of manually
specifying a list of includes to give to "spatch(1)".
As noted upthread of [1] a naïve removal of "--all-includes" will
result in broken *.cocci patches, but if we know the exhaustive
list of includes via COMPUTE_HEADER_DEPENDENCIES we don't need to
re-scan for them, we could grab the headers to include from the
.depend.d/<file>.o.d and supply them with the "--include" option to
spatch(1).q
1. https://lore.kernel.org/git/87ft18tcog.fsf@evledraar.gmail.com/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Fix an issue with a rule added in 9b45f49981 (object-store: prepare
has_{sha1, object}_file to handle any repo, 2018-11-13). We've been
spewing out this warning into our $@.log since that rule was added:
warning: rule starting on line 21: metavariable F not used in the - or context code
We should do a better job of scouring our coccinelle log files for
such issues, but for now let's fix this as a one-off.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
A coccinelle rule (in contrib/) to encourage use of COPY_ARRAY
macro has been improved.
* rs/cocci-array-copy:
cocci: avoid normalization rules for memcpy
Some of the rules for using COPY_ARRAY instead of memcpy with sizeof are
intended to reduce the number of sizeof variants to deal with. They can
have unintended side effects if only they match, but not the one for the
COPY_ARRAY conversion at the end.
Avoid these side effects by instead using a self-contained rule for each
combination of array and pointer for source and destination which lists
all sizeof variants inline.
This lets "make contrib/coccinelle/array.cocci.patch" take 15% longer on
my machine, but gives peace of mind that no incomplete transformation
will be generated.
Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Generalize the newly added "unused.cocci" rule to find more than just
"struct strbuf", let's have it find the same unused patterns for
"struct string_list", as well as other code that uses
similar-looking *_{release,clear,free}() and {release,clear,free}_*()
functions.
We're intentionally loose in accepting e.g. a "strbuf_init(&sb)"
followed by a "string_list_clear(&sb, 0)". It's assumed that the
compiler will catch any such invalid code, i.e. that our
constructors/destructors don't take a "void *".
See [1] for example of code that would be covered by the
"get_worktrees()" part of this rule. We'd still need work that the
series is based on (we were passing "worktrees" to a function), but
could now do the change in [1] automatically.
1. https://lore.kernel.org/git/Yq6eJFUPPTv%2Fzc0o@coredump.intra.peff.net/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a coccinelle rule to remove "struct strbuf" initialization
followed by calling "strbuf_release()" function, without any uses of
the strbuf in the same function.
See the tests in contrib/coccinelle/tests/unused.{c,res} for what it's
intended to find and replace.
The inclusion of "contrib/scalar/scalar.c" is because "spatch" was
manually run on it (we don't usually run spatch on contrib).
Per the "buggy code" comment we also match a strbuf_init() before the
xmalloc(), but we're not seeking to be so strict as to make checks
that the compiler will catch for us redundant. Saying we'll match
either "init" or "xmalloc" lines makes the rule simpler.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a "coccicheck-test" target to test our *.cocci rules, and as a
demonstration add tests for the rules added in 39ea59a257 (remove
unnecessary NULL check before free(3), 2016-10-08) and
1b83d1251e (coccinelle: add a rule to make "expression" code use
FREE_AND_NULL(), 2017-06-15).
I considered making use of the "spatch --test" option, and the choice
of a "tests" over a "t" directory is to make these tests compatible
with such a future change.
Unfortunately "spatch --test" doesn't return meaningful exit codes,
AFAICT you need to "grep" its output to see if the *.res is what you
expect. There's "--test-okfailed", but I didn't find a way to sensibly
integrate those (it relies on some in-between status files, but
doesn't help with the status codes).
Instead let's use a "--sp-file" pattern similar to the main
"coccicheck" rule, with the difference that we use and compare the
two *.res files with cmp(1).
The --very-quiet and --no-show-diff options ensure that we don't need
to pipe stdout and stderr somewhere. Unlike the "%.cocci.patch" rule
we're not using the diff.
The "cmp || git diff" is optimistically giving us better output on
failure, but even if we only have POSIX cmp and no system git
installed we'll still fail with the "cmp", just with an error message
that isn't as friendly. The "2>/dev/null" is in case we don't have a
"git" installed.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 8d4d86b0 (cache: remove null_sha1, 2019-08-18) removed the
is_null_sha1() function, rewrite rules to correct callers of the
function to use is_null_oid() instead has become irrelevant, as any
new callers of the function will get caught by the compiler much
more quickly without spending cycles on Coccinelle.
Remove these rules.
Signed-off-by: Junio C Hamano <gitster@pobox.com>