Hold the ref_cache instance for the main repository in a dedicated,
statically-allocated instance to avoid the need for a function call
and a linked-list traversal when it is needed.
Suggested by: Heiko Voigt <hvo...@hvoigt.net>
Signed-off-by: Michael Haggerty <mhag...@alum.mit.edu>
---
refs.c | 60 +++++++++++++++++++++++++++++++-----------------------------
1 file changed, 31 insertions(+), 29 deletions(-)
diff --git a/refs.c b/refs.c
index cfcb42f..13e5bc8 100644
--- a/refs.c
+++ b/refs.c
@@ -812,9 +812,13 @@ static struct ref_cache {
struct ref_cache *next;
struct ref_entry *loose;
struct ref_entry *packed;
- /* The submodule name, or "" for the main repo. */
- char name[FLEX_ARRAY];
-} *ref_cache;
+ /*
+ * The submodule name, or "" for the main repo. We allocate
+ * length 1 rather than FLEX_ARRAY so that the main ref_cache
+ * is initialized correctly.
+ */
+ char name[1];
+} ref_cache, *submodule_ref_caches;
static void clear_packed_ref_cache(struct ref_cache *refs)
{
@@ -852,18 +856,18 @@ static struct ref_cache *create_ref_cache(const char
*submodule)
*/
static struct ref_cache *get_ref_cache(const char *submodule)
{
- struct ref_cache *refs = ref_cache;
- if (!submodule)
- submodule = "";
- while (refs) {
+ struct ref_cache *refs;
+
+ if (!submodule || !*submodule)
+ return &ref_cache;
+
+ for (refs = submodule_ref_caches; refs; refs = refs->next)
if (!strcmp(submodule, refs->name))
return refs;
- refs = refs->next;
- }
refs = create_ref_cache(submodule);
- refs->next = ref_cache;
- ref_cache = refs;
+ refs->next = submodule_ref_caches;
+ submodule_ref_caches = refs;
return refs;
}
@@ -1012,8 +1016,8 @@ static struct ref_dir *get_packed_refs(struct ref_cache
*refs)
void add_packed_ref(const char *refname, const unsigned char *sha1)
{
- add_ref(get_packed_refs(get_ref_cache(NULL)),
- create_ref_entry(refname, sha1, REF_ISPACKED, 1));
+ add_ref(get_packed_refs(&ref_cache),
+ create_ref_entry(refname, sha1, REF_ISPACKED, 1));
}
/*
@@ -1188,7 +1192,7 @@ int resolve_gitlink_ref(const char *path, const char
*refname, unsigned char *sh
*/
static struct ref_entry *get_packed_ref(const char *refname)
{
- return find_ref(get_packed_refs(get_ref_cache(NULL)), refname);
+ return find_ref(get_packed_refs(&ref_cache), refname);
}
const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int
reading, int *flag)
@@ -1589,7 +1593,7 @@ int head_ref_submodule(const char *submodule, each_ref_fn
fn, void *cb_data)
int for_each_ref(each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref(get_ref_cache(NULL), "", fn, 0, 0, cb_data);
+ return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);
}
int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void
*cb_data)
@@ -1599,7 +1603,7 @@ int for_each_ref_submodule(const char *submodule,
each_ref_fn fn, void *cb_data)
int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref(get_ref_cache(NULL), prefix, fn, strlen(prefix),
0, cb_data);
+ return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0,
cb_data);
}
int for_each_ref_in_submodule(const char *submodule, const char *prefix,
@@ -1640,7 +1644,7 @@ int for_each_remote_ref_submodule(const char *submodule,
each_ref_fn fn, void *c
int for_each_replace_ref(each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref(get_ref_cache(NULL), "refs/replace/", fn, 13, 0,
cb_data);
+ return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);
}
int head_ref_namespaced(each_ref_fn fn, void *cb_data)
@@ -1663,7 +1667,7 @@ int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
struct strbuf buf = STRBUF_INIT;
int ret;
strbuf_addf(&buf, "%srefs/", get_git_namespace());
- ret = do_for_each_ref(get_ref_cache(NULL), buf.buf, fn, 0, 0, cb_data);
+ ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);
strbuf_release(&buf);
return ret;
}
@@ -1705,7 +1709,7 @@ int for_each_glob_ref(each_ref_fn fn, const char
*pattern, void *cb_data)
int for_each_rawref(each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref(get_ref_cache(NULL), "", fn, 0,
+ return do_for_each_ref(&ref_cache, "", fn, 0,
DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
}
@@ -1911,7 +1915,7 @@ static struct ref_lock *lock_ref_sha1_basic(const char
*refname,
* name is a proper prefix of our refname.
*/
if (missing &&
- !is_refname_available(refname, NULL,
get_packed_refs(get_ref_cache(NULL)))) {
+ !is_refname_available(refname, NULL, get_packed_refs(&ref_cache)))
{
last_errno = ENOTDIR;
goto error_return;
}
@@ -2100,7 +2104,7 @@ int pack_refs(unsigned int flags)
write_or_die(cbdata.fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
- do_for_each_entry(get_ref_cache(NULL), "", pack_one_ref, &cbdata);
+ do_for_each_entry(&ref_cache, "", pack_one_ref, &cbdata);
if (commit_lock_file(&packlock) < 0)
die_errno("unable to overwrite old ref-pack file");
prune_refs(cbdata.ref_to_prune);
@@ -2126,7 +2130,6 @@ static int repack_ref_fn(struct ref_entry *entry, void
*cb_data)
static int repack_without_ref(const char *refname)
{
int fd;
- struct ref_cache *refs = get_ref_cache(NULL);
struct ref_dir *packed;
if (!get_packed_ref(refname))
@@ -2137,8 +2140,8 @@ static int repack_without_ref(const char *refname)
unable_to_lock_error(git_path("packed-refs"), errno);
return error("cannot delete '%s' from packed refs", refname);
}
- clear_packed_ref_cache(refs);
- packed = get_packed_refs(refs);
+ clear_packed_ref_cache(&ref_cache);
+ packed = get_packed_refs(&ref_cache);
/* Remove refname from the cache. */
if (remove_entry(packed, refname) == -1) {
/*
@@ -2178,7 +2181,7 @@ int delete_ref(const char *refname, const unsigned char
*sha1, int delopt)
ret |= repack_without_ref(lock->ref_name);
unlink_or_warn(git_path("logs/%s", lock->ref_name));
- clear_loose_ref_cache(get_ref_cache(NULL));
+ clear_loose_ref_cache(&ref_cache);
unlock_ref(lock);
return ret;
}
@@ -2200,7 +2203,6 @@ int rename_ref(const char *oldrefname, const char
*newrefname, const char *logms
struct stat loginfo;
int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
const char *symref = NULL;
- struct ref_cache *refs = get_ref_cache(NULL);
if (log && S_ISLNK(loginfo.st_mode))
return error("reflog for %s is a symlink", oldrefname);
@@ -2212,10 +2214,10 @@ int rename_ref(const char *oldrefname, const char
*newrefname, const char *logms
if (!symref)
return error("refname %s not found", oldrefname);
- if (!is_refname_available(newrefname, oldrefname,
get_packed_refs(refs)))
+ if (!is_refname_available(newrefname, oldrefname,
get_packed_refs(&ref_cache)))
return 1;
- if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
+ if (!is_refname_available(newrefname, oldrefname,
get_loose_refs(&ref_cache)))
return 1;
if (log && rename(git_path("logs/%s", oldrefname),
git_path(TMP_RENAMED_LOG)))
@@ -2471,7 +2473,7 @@ int write_ref_sha1(struct ref_lock *lock,
unlock_ref(lock);
return -1;
}
- clear_loose_ref_cache(get_ref_cache(NULL));
+ clear_loose_ref_cache(&ref_cache);
if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
(strcmp(lock->ref_name, lock->orig_ref_name) &&
log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) <
0)) {
--
1.8.2.1
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
