diff --git a/src/include/catalog/dependency.h b/src/include/catalog/dependency.h
index bed1a791..4bde0c31 100644
--- a/src/include/catalog/dependency.h
+++ b/src/include/catalog/dependency.h
@@ -213,6 +213,7 @@ typedef enum ObjectClass {
 #define PERFORM_DELETION_INVALID            0x0000
 #define PERFORM_DELETION_INTERNAL			0x0001
 #define PERFORM_DELETION_CONCURRENTLY		0x0002
+#define PERFORM_DELETION_CONCURRENTLY_LOCK  0x0020    /* normal drop with concurrent lock mode */
 
 /* ObjectAddressExtra flag bits */
 #define DEPFLAG_ORIGINAL 0x0001  /* an original deletion target */
@@ -294,6 +295,9 @@ extern long changeDependencyFor(Oid classId,
                                 Oid oldRefObjectId,
                                 Oid newRefObjectId);
 
+/*use for reindex concurrently*/
+extern long changeDependenciesOn(Oid refClassId,Oid oldRefObjectId,Oid newRefObjectId);
+
 extern Oid	getExtensionOfObject(Oid classId, Oid objectId);
 
 extern bool sequenceIsOwned(Oid seqId, Oid *tableId, int32 *colId);
@@ -306,6 +310,9 @@ extern Oid	get_constraint_index(Oid constraintId);
 
 extern Oid	get_index_constraint(Oid indexId);
 
+/* use for reindex concurrently */
+extern List *get_index_ref_constraints(Oid indexId);
+
 /* in pg_shdepend.c */
 extern void recordSharedDependencyOn(ObjectAddress *depender,
                                      ObjectAddress *referenced,
diff --git a/src/include/catalog/index.h b/src/include/catalog/index.h
index 0ed3e5d3..ebe0cafb 100644
--- a/src/include/catalog/index.h
+++ b/src/include/catalog/index.h
@@ -125,12 +125,36 @@ extern Oid index_create(Relation heapRelation, const char *indexRelationName, Oi
                         IndexCreateExtraArgs *extra, bool useLowLockLevel = false,
                         int8 relindexsplit = 0);
 
+/* ues for reindex concurrently*/
+extern Oid index_concurrently_create_copy(Relation heapRelation, Oid oldIndexId, const char *newName);
+
+/* use for reindex concurrently*/
+extern void index_concurrently_build(Oid heapRelationId, Oid indexRelationId, bool isPrimary, AdaptMem* memInfo = NULL, bool dbWide = false);
+
+/* use for reindex concurrently*/
+extern void index_concurrently_swap(Oid newIndexId, Oid oldIndexId, const char *oldName);
+
+/* use for reindex concurrently*/
+extern void index_concurrently_set_dead(Oid heapId, Oid indexId);
+
+/* use for reindex concurrently partition */
+extern Oid index_concurrently_part_create_copy(Oid oldIndexPartId, const char *newName);
+
+/* use for reindex concurrently partition */
+extern void index_concurrently_part_build(Oid heapRelationId, Oid heapPartitionId, Oid indexRelationId, Oid IndexPartitionId, AdaptMem* memInfo = NULL, bool dbWide = false);
+
+/* use for reindex concurrently partition */
+extern void index_concurrently_part_swap(Relation indexRelation, Oid newIndexPartId, Oid oldIndexPartId, const char *oldName);
+
+
+
 extern void index_constraint_create(Relation heapRelation, Oid indexRelationId, IndexInfo *indexInfo,
                                     const char *constraintName, char constraintType, bool deferrable,
                                     bool initdeferred, bool mark_as_primary, bool update_pgindex,
                                     bool remove_old_dependencies, bool allow_system_table_mods);
 
-extern void index_drop(Oid indexId, bool concurrent);
+/* change input: add concurrent_lock_mode */
+extern void index_drop(Oid indexId, bool concurrent, bool concurrent_lock_mode = false);
 
 extern IndexInfo *BuildIndexInfo(Relation index);
 extern IndexInfo *BuildDummyIndexInfo(Relation index);
@@ -173,7 +197,7 @@ extern double IndexBuildVectorBatchScan(Relation heapRelation, Relation indexRel
                                         void *transferFuncs);
 
 
-extern void validate_index(Oid heapId, Oid indexId, Snapshot snapshot);
+extern void validate_index(Oid heapId, Oid indexId, Snapshot snapshot, bool isPart = false);
 extern void validate_index_heapscan(
     Relation heapRelation, Relation indexRelation, IndexInfo* indexInfo, Snapshot snapshot, v_i_state* state);
 
@@ -201,6 +225,9 @@ extern bool ReindexIsProcessingHeap(Oid heapOid);
 extern bool ReindexIsProcessingIndex(Oid indexOid);
 extern Oid IndexGetRelation(Oid indexId, bool missing_ok);
 
+extern Oid PartIndexGetPartition(Oid partIndexId, bool missing_ok);
+extern Oid PartIdGetParentId(Oid partIndexId, bool missing_ok);
+
 typedef struct
 {
     Oid  existingPSortOid;
@@ -232,6 +259,7 @@ extern void PartitionNameCallbackForIndexPartition(Oid partitionedRelationOid,
                                                    LOCKMODE callbackobj_lockMode);
 extern void reindex_partIndex(Relation heapRel,  Partition heapPart, Relation indexRel , Partition indexPart);
 extern bool reindexPartition(Oid relid, Oid partOid, int flags, int reindexType);
+extern Oid heapPartitionIdGetindexPartitionId(Oid indexId, Oid partOid);
 extern void AddGPIForPartition(Oid partTableOid, Oid partOid);
 void AddCBIForPartition(Relation partTableRel, Relation tempTableRel, const List* indexRelList, 
     const List* indexDestOidList);
diff --git a/src/include/commands/defrem.h b/src/include/commands/defrem.h
index 361781d5..09a2755c 100644
--- a/src/include/commands/defrem.h
+++ b/src/include/commands/defrem.h
@@ -23,11 +23,14 @@ extern void RemoveObjects(DropStmt* stmt, bool missing_ok, bool is_securityadmin
 /* commands/indexcmds.c */
 extern Oid DefineIndex(Oid relationId, IndexStmt* stmt, Oid indexRelationId, bool is_alter_table, bool check_rights,
     bool skip_build, bool quiet);
-extern void ReindexIndex(RangeVar* indexRelation, const char* partition_name, AdaptMem* mem_info);
-extern void ReindexTable(RangeVar* relation, const char* partition_name, AdaptMem* mem_info);
-extern void ReindexInternal(RangeVar* relation, const char* partition_name);
 
-extern void ReindexDatabase(const char* databaseName, bool do_system, bool do_user, AdaptMem* mem_info);
+/*add input for reindex concurrently*/    
+extern void ReindexIndex(RangeVar* indexRelation, const char* partition_name, AdaptMem* mem_info, bool concurrent);
+extern void ReindexTable(RangeVar* relation, const char* partition_name, AdaptMem* mem_info, bool concurrent);
+extern void ReindexInternal(RangeVar* relation, const char* partition_name, bool concurrent);
+
+/*add input for reindex concurrently */
+extern void ReindexDatabase(const char* databaseName, bool do_system, bool do_user, AdaptMem* mem_info, bool concurrent);
 extern char* makeObjectName(const char* name1, const char* name2, const char* label, bool reverseTruncate = false);
 extern char* ChooseRelationName(
     const char* name1, const char* name2, const char* label, size_t labelLength, Oid namespaceid,