diff options
author | Jeff King <peff@peff.net> | 2016-01-23 01:29:30 +0300 |
---|---|---|
committer | Junio C Hamano <gitster@pobox.com> | 2016-01-25 22:42:13 +0300 |
commit | a2d5156c2b0e6dbffc216b4a673156487a2f8b65 (patch) | |
tree | 6334583037d3290eda285269f9dac7b8c429013f /t/perf | |
parent | ffd036b1286687589f5ce5513ee69c06ee53691e (diff) |
resolve_gitlink_ref: ignore non-repository paths
When we want to look up a submodule ref, we use
get_ref_cache(path) to find or auto-create its ref cache.
But if we feed a path that isn't actually a git repository,
we blindly create the ref cache, and then may die deeper in
the code when we try to access it. This is a problem because
many callers speculatively feed us a path that looks vaguely
like a repository, and expect us to tell them when it is
not.
This patch teaches resolve_gitlink_ref to reject
non-repository paths without creating a ref_cache. This
avoids the die(), and also performs better if you have a
large number of these faux-submodule directories (because
the ref_cache lookup is linear, under the assumption that
there won't be a large number of submodules).
To accomplish this, we also break get_ref_cache into two
pieces: the lookup and auto-creation (the latter is lumped
into create_ref_cache). This lets us first cheaply ask our
cache "is it a submodule we know about?" If so, we can avoid
repeating our filesystem lookup. So lookups of real
submodules are not penalized; they examine the submodule's
.git directory only once.
The test in t3000 demonstrates a case where this improves
correctness (we used to just die). The new perf case in
p7300 shows off the speed improvement in an admittedly
pathological repository:
Test HEAD^ HEAD
----------------------------------------------------------------
7300.4: ls-files -o 66.97(66.15+0.87) 0.33(0.08+0.24) -99.5%
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 't/perf')
-rwxr-xr-x | t/perf/p7300-clean.sh | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/t/perf/p7300-clean.sh b/t/perf/p7300-clean.sh index ec94cdd657..7c1888a27e 100755 --- a/t/perf/p7300-clean.sh +++ b/t/perf/p7300-clean.sh @@ -28,4 +28,8 @@ test_perf 'clean many untracked sub dirs, ignore nested git' ' git clean -n -q -f -f -d 100000_sub_dirs/ ' +test_perf 'ls-files -o' ' + git ls-files -o +' + test_done |