1 files changed, 15 insertions, 23 deletions

diff --git a/src/backend/executor/nodeIndexscan.c b/src/backend/executor/nodeIndexscan.c
index 404076d5930..638b17b07cb 100644
--- a/src/backend/executor/nodeIndexscan.c
+++ b/src/backend/executor/nodeIndexscan.c
@@ -24,6 +24,7 @@
  *		ExecIndexRestrPos		restores scan position.
  *		ExecIndexScanEstimate	estimates DSM space needed for parallel index scan
  *		ExecIndexScanInitializeDSM initialize DSM for parallel indexscan
+ *		ExecIndexScanReInitializeDSM reinitialize DSM for fresh scan
  *		ExecIndexScanInitializeWorker attach to DSM info in parallel worker
  */
 #include "postgres.h"
@@ -577,18 +578,6 @@ ExecIndexScan(PlanState *pstate)
 void
 ExecReScanIndexScan(IndexScanState *node)
 {
-	bool		reset_parallel_scan = true;
-
-	/*
-	 * If we are here to just update the scan keys, then don't reset parallel
-	 * scan.  We don't want each of the participating process in the parallel
-	 * scan to update the shared parallel scan state at the start of the scan.
-	 * It is quite possible that one of the participants has already begun
-	 * scanning the index when another has yet to start it.
-	 */
-	if (node->iss_NumRuntimeKeys != 0 && !node->iss_RuntimeKeysReady)
-		reset_parallel_scan = false;
-
 	/*
 	 * If we are doing runtime key calculations (ie, any of the index key
 	 * values weren't simple Consts), compute the new key values.  But first,
@@ -614,21 +603,11 @@ ExecReScanIndexScan(IndexScanState *node)
 			reorderqueue_pop(node);
 	}
 
-	/*
-	 * Reset (parallel) index scan.  For parallel-aware nodes, the scan
-	 * descriptor is initialized during actual execution of node and we can
-	 * reach here before that (ex. during execution of nest loop join).  So,
-	 * avoid updating the scan descriptor at that time.
-	 */
+	/* reset index scan */
 	if (node->iss_ScanDesc)
-	{
 		index_rescan(node->iss_ScanDesc,
 					 node->iss_ScanKeys, node->iss_NumScanKeys,
 					 node->iss_OrderByKeys, node->iss_NumOrderByKeys);
-
-		if (reset_parallel_scan && node->iss_ScanDesc->parallel_scan)
-			index_parallelrescan(node->iss_ScanDesc);
-	}
 	node->iss_ReachedEnd = false;
 
 	ExecScanReScan(&node->ss);
@@ -1717,6 +1696,19 @@ ExecIndexScanInitializeDSM(IndexScanState *node,
 }
 
 /* ----------------------------------------------------------------
+ *		ExecIndexScanReInitializeDSM
+ *
+ *		Reset shared state before beginning a fresh scan.
+ * ----------------------------------------------------------------
+ */
+void
+ExecIndexScanReInitializeDSM(IndexScanState *node,
+							 ParallelContext *pcxt)
+{
+	index_parallelrescan(node->iss_ScanDesc);
+}
+
+/* ----------------------------------------------------------------
  *		ExecIndexScanInitializeWorker
  *
  *		Copy relevant information from TOC into planstate.