Junio C HamanoWhen "git checkout" wants to create a path, e.g. a/b/c/d/e, after seeing if the entire thing already exists (in which case we check if that is up-to-date and do not bother to check it out, or we unlink and recreate it), we validate that the leading directory path is without funny symlinks by seeing a/, a/b/, a/b/c/ and then a/b/c/d/ are all without funny symlinks, by calling has_dirs_only_path() in this order.
When we are checking out many files (imagine: initial checkout), however, it is likely that an earlier checkout would have already made sure that the leading directory a/b/c/d/ is in good order; by first checking the whole path a/b/c/d/ first, we can often bypass calls to has_dirs_only_path() for leading part.
This cuts down the number of calls to has_dirs_only_path() for checking out Linux kernel sources afresh from 190k down to 98k.
Signed-off-by: Junio C Hamano <gitster@pobox.com> ---
* Just a random experimental change I was playing with today, looking for low hanging fruits before having to thread the entire checkout codepath.
entry.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)
Show changes to entry.c +10 −2
diff --git a/entry.c b/entry.c index 7b7aa81..e2c0ac6 100644 --- a/entry.c +++ b/entry.c @@ -6,9 +6,17 @@ static void create_directories(const char *path, int path_len, const struct checkout *state) { - char *buf = xmalloc(path_len + 1); - int len = 0; + char *buf; + int len; + + for (len = path_len - 1; 0 <= len; len--) + if (path[len] == '/') + break; + if (has_dirs_only_path(path, len, state->base_dir_len)) + return; /* ok, we have the whole leading directory */ + buf = xmalloc(path_len + 1); + len = 0; while (len < path_len) { do { buf[len] = path[len];
