Function CatCacheInvalidate

src/backend/utils/cache/catcache.c:552–605

* CatCacheInvalidate * * Invalidate entries in the specified cache, given a hash value. * * We delete cache entries that match the hash value, whether positive * or negative. We don't care whether the invalidation is the result * of a tuple insertion or a deletion. * * We used to try to match positive cache entries by TID, but that is * unsafe after a VACUUM FULL on a system catalog: an

 *	This routine is only quasi-public: it should only be used by inval.c.
 */
void
CatCacheInvalidate(CatCache *cache, uint32 hashValue)
{
	Index		hashIndex;
	dlist_mutable_iter iter;

	CACHE_elog(DEBUG2, "CatCacheInvalidate: called");

	/*
	 * We don't bother to check whether the cache has finished initialization
	 * yet; if not, there will be no entries in it so no problem.
	 */

	/*
	 * Invalidate *all* CatCLists in this cache; it's too hard to tell which
	 * searches might still be correct, so just zap 'em all.
	 */
	dlist_foreach_modify(iter, &cache->cc_lists)
	{
		CatCList   *cl = dlist_container(CatCList, cache_elem, iter.cur);

		if (cl->refcount > 0)
			cl->dead = true;
		else
			CatCacheRemoveCList(cache, cl);
	}

	/*
	 * inspect the proper hash bucket for tuple matches
	 */
	hashIndex = HASH_INDEX(hashValue, cache->cc_nbuckets);
	dlist_foreach_modify(iter, &cache->cc_bucket[hashIndex])
	{
		CatCTup    *ct = dlist_container(CatCTup, cache_elem, iter.cur);

		if (hashValue == ct->hash_value)
		{
			if (ct->refcount > 0 ||
				(ct->c_list && ct->c_list->refcount > 0))
			{
				ct->dead = true;
				/* list, if any, was marked dead above */
				Assert(ct->c_list == NULL || ct->c_list->dead);
			}
			else
				CatCacheRemoveCTup(cache, ct);
			CACHE_elog(DEBUG2, "CatCacheInvalidate: invalidated");
#ifdef CATCACHE_STATS
			cache->cc_invals++;
#endif
			/* could be multiple matches, so keep looking! */
		}
	}
}

/* ----------------------------------------------------------------
 *					   public functions