Add table relcache invalidation to index builds.

It's necessary to make sure that owning tables have a relcache
invalidation prior to advancing the command counter to make
newly-entered catalog tuples for the index visible.  inval.c must be
able to maintain the consistency of the local caches in the event of
transaction abort.  There is usually only a problem when CREATE INDEX
transactions abort, since there is a generic invalidation once we reach
index_update_stats().

This bug is of long standing.  Problems were made much more likely by
the addition of parallel CREATE INDEX (commit 9da0cc35284), but it is
strongly suspected that similar problems can be triggered without
involving plan_create_index_workers().  (plan_create_index_workers()
triggers a relcache build or rebuild, which previously only happened in
rare edge cases.)

Author: Peter Geoghegan
Reported-By: Luca Ferrari
Diagnosed-By: Andres Freund
Reviewed-By: Andres Freund
Discussion: https://postgr.es/m/CAKoxK+5fVodiCtMsXKV_1YAKXbzwSfp7DgDqUmcUAzeAhf=HEQ@mail.gmail.com
Backpatch: 9.3-

diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index 13202461fe5dfbbc67c00f5b7421b78b25ee6fb7..074f4ec9bc80b9252c15356a8c2fe020091e791b 100644 (file)
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -887,6 +887,12 @@ index_create(Relation heapRelation,
                        !deferrable,
                        !concurrent);
 
+   /*
+    * Register relcache invalidation on the indexes' heap relation, to
+    * maintain consistency of its index list
+    */
+   CacheInvalidateRelcache(heapRelation);
+
    /*
     * Register constraint and dependencies for the index.
     *