From 9da31cb027aa5dac3d4914a88faa8830f0578c88 Mon Sep 17 00:00:00 2001 From: Michael Haggerty Date: Mon, 22 Apr 2013 21:52:41 +0200 Subject: [PATCH] refs: handle the main ref_cache specially 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 Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano --- refs.c | 60 ++++++++++++++++++++++++++++++---------------------------- 1 file changed, 31 insertions(+), 29 deletions(-) diff --git a/refs.c b/refs.c index 238670d8fc..fa53b39c28 100644 --- a/refs.c +++ b/refs.c @@ -811,9 +811,13 @@ 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) { @@ -851,18 +855,18 @@ 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; } @@ -1011,8 +1015,8 @@ 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)); } /* @@ -1187,7 +1191,7 @@ 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) @@ -1592,7 +1596,7 @@ 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) @@ -1602,7 +1606,7 @@ 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, @@ -1643,7 +1647,7 @@ 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) @@ -1666,7 +1670,7 @@ 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; } @@ -1708,7 +1712,7 @@ 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); } @@ -1914,7 +1918,7 @@ 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; } @@ -2103,7 +2107,7 @@ 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); @@ -2161,7 +2165,6 @@ 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)) @@ -2172,8 +2175,8 @@ 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) { /* @@ -2213,7 +2216,7 @@ 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; } @@ -2235,7 +2238,6 @@ 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); @@ -2247,10 +2249,10 @@ 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))) @@ -2506,7 +2508,7 @@ 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)) { -- 2.39.2