refs: do not invalidate the packed-refs cache unnecessarily
Now that we keep track of the packed-refs file metadata, we can detect when the packed-refs file has been modified since we last read it, and we do so automatically every time that get_packed_ref_cache() is called. So there is no need to invalidate the cache automatically when lock_packed_refs() is called; usually the old copy will still be valid. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Michael Haggerty committed
Jun 20, 2013 at 10:37 UTC
5d478f5ca1792e7576ac13aaf75f09099ce99afb
1 file changed
+6
-3
refs.c
+6
-3
@@ -2136,11 +2136,14 @@ int lock_packed_refs(int flags)
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{
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struct packed_ref_cache *packed_ref_cache;
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- /* Discard the old cache because it might be invalid: */
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- clear_packed_ref_cache(&ref_cache);
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if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)
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return -1;
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- /* Read the current packed-refs while holding the lock: */
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+ /*
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+ * Get the current packed-refs while holding the lock. If the
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+ * packed-refs file has been modified since we last read it,
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+ * this will automatically invalidate the cache and re-read
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+ * the packed-refs file.
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+ */
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packed_ref_cache = get_packed_ref_cache(&ref_cache);
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packed_ref_cache->lock = &packlock;
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/* Increment the reference count to prevent it from being freed: */