[PATCH 01/10] packed-backend: don't adjust the reference count on lock/unlock
- From
Michael Haggerty <mhagger@alum.mit.edu>
- Date
- Aug 29, 2017, 08:20 UTC
- Message-ID
- <c5d66cadb70efdb5b5ce91fbcc5673621f5d4792.1503993268.git.mhagger@alum.mit.edu>
- In-Reply-To
- <cover.1503993268.git.mhagger@alum.mit.edu>
The old code incremented the packed ref cache reference count when acquiring the packed-refs lock, and decremented the count when releasing the lock. This is unnecessary because a locked packed-refs file cannot be changed, so there is no reason for the cache to become stale.
Moreover, the extra reference count causes a problem if we intentionally clear the packed refs cache, as we sometimes need to do if we change the cache in anticipation of writing a change to disk, but then the write to disk fails. In that case, `packed_refs_unlock()` would have no easy way to find the cache whose reference count it needs to decrement.
This whole issue will soon become moot due to upcoming changes that avoid changing the in-memory cache as part of updating the packed-refs on disk, but this change makes that transition easier.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> --- refs/packed-backend.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/refs/packed-backend.c b/refs/packed-backend.c index 412c85034f..7e348feac3 100644 --- a/refs/packed-backend.c +++ b/refs/packed-backend.c @@ -525,7 +525,6 @@ int packed_refs_lock(struct ref_store *ref_store, int flags, struct strbuf *err) "packed_refs_lock"); static int timeout_configured = 0; static int timeout_value = 1000; - struct packed_ref_cache *packed_ref_cache; if (!timeout_configured) { git_config_get_int("core.packedrefstimeout", &timeout_value); @@ -560,9 +559,7 @@ int packed_refs_lock(struct ref_store *ref_store, int flags, struct strbuf *err) */ validate_packed_ref_cache(refs); - packed_ref_cache = get_packed_ref_cache(refs); - /* Increment the reference count to prevent it from being freed: */ - acquire_packed_ref_cache(packed_ref_cache); + get_packed_ref_cache(refs); return 0; } @@ -576,7 +573,6 @@ void packed_refs_unlock(struct ref_store *ref_store) if (!is_lock_file_locked(&refs->lock)) die("BUG: packed_refs_unlock() called when not locked"); rollback_lock_file(&refs->lock); - release_packed_ref_cache(refs->cache); } int packed_refs_is_locked(struct ref_store *ref_store)
-- 2.14.1