From: Robert Haas <rhaas@postgresql.org>
Date: Fri, 27 Jul 2012 18:19:47 +0000 (+0000)
Subject: Fix another bug related to marked CHashPtrs.
X-Git-Url: http://git.postgresql.org/gitweb/static/gitweb.js?a=commitdiff_plain;h=6c84f78a919097ebaf89d1cf5fab46acbf99ce7b;p=users%2Fandresfreund%2Fpostgres.git

Fix another bug related to marked CHashPtrs.
---

diff --git a/src/backend/utils/hash/chash.c b/src/backend/utils/hash/chash.c
index 4855bc8ace..700a2e9327 100644
--- a/src/backend/utils/hash/chash.c
+++ b/src/backend/utils/hash/chash.c
@@ -463,6 +463,7 @@ retry:
 		 * in the table.  Even for a quite modestly size table this is likely
 		 * to exceed the number of CPU cores.
 		 */
+		Assert(!CHashPtrIsMarked(scan.target));
 		nnew->next = scan.target;
 		if (!__sync_bool_compare_and_swap(scan.pointer_to_target,
 										  scan.target, new))
@@ -557,6 +558,9 @@ CHashDelete(CHashTable table, void *entry)
  * case, res->pointer_to_target will a pointer to the address where the value
  * of target was found.  res->target_node will be a pointer to the address of
  * the CHashNode with offset res->target, unless res->target is invalid.
+ *
+ * NB: If you change this function, make sure to adjust CHashBucketCleanup
+ * similarly.
  */
 static void
 CHashBucketScan(CHashTable table,
@@ -622,7 +626,7 @@ zap:
 				 */
 				CHashAddToGarbage(table, hashcode & table->bucket_mask,
 								  target);
-				target = next;
+				target = CHashPtrUnmark(next);
 				continue;
 			}
 			else
@@ -948,7 +952,7 @@ retry:
 				/* We removed the item. */
 				CHashAddToGarbage(table, hashcode & table->bucket_mask,
 								  target);
-				target = next;
+				target = CHashPtrUnmark(next);
 				continue;
 			}
 			else