[PATCH 1/2] rm: only refresh entries that we may touch

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

This gets rid of the whole tree cache refresh. Instead only path that
we touch will get refreshed. We may still lstat() more than needed,
but it'd be better playing safe.

This potentially reduces a large number of lstat() on big trees. Take
gentoo-x86 tree for example, which has roughly 80k files:

Unmodified Git:

$ time git rm --cached skel.ChangeLog
rm 'skel.ChangeLog'

real    0m1.323s
user    0m0.806s
sys     0m0.517s

Modified Git:

$ time git rm --cached skel.ChangeLog
rm 'skel.ChangeLog'

real    0m0.903s
user    0m0.780s
sys     0m0.100s

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 builtin-rm.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/builtin-rm.c b/builtin-rm.c
index 57975db..4cac3d1 100644
--- a/builtin-rm.c
+++ b/builtin-rm.c
@@ -169,7 +169,6 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
 
 	if (read_cache() < 0)
 		die("index file corrupt");
-	refresh_cache(REFRESH_QUIET);
 
 	pathspec = get_pathspec(prefix, argv);
 	seen = NULL;
@@ -181,6 +180,7 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
 		struct cache_entry *ce = active_cache[i];
 		if (!match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, seen))
 			continue;
+		refresh_cache_entry(ce, 1);
 		add_list(ce->name);
 	}
 
-- 
1.6.6.181.g5ee6