diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 26ccd7f481..d8faf41c94 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -1462,6 +1462,18 @@ RemoveRelations(DropStmt *drop) errmsg("cannot drop partitioned index \"%s\" concurrently", rel->relname))); + /* + * If we're told to drop a partitioned index, we must acquire lock on + * all the children of its parent partitioned table before proceeding. + * Otherwise we'd try to lock the child index partitions before their + * tables, leading to potential deadlock against other sessions that + * will lock those objects in the other order. + */ + if (state.actual_relkind == RELKIND_PARTITIONED_INDEX) + (void) find_all_inheritors(state.heapOid, + AccessExclusiveLock, + NULL); + /* OK, we're ready to delete this one */ obj.classId = RelationRelationId; obj.objectId = relOid; diff --git a/src/test/isolation/expected/partition-drop-index-locking.out b/src/test/isolation/expected/partition-drop-index-locking.out new file mode 100644 index 0000000000..9acd51dfde --- /dev/null +++ b/src/test/isolation/expected/partition-drop-index-locking.out @@ -0,0 +1,100 @@ +Parsed test spec with 3 sessions + +starting permutation: s1begin s1lock s2begin s2drop s1select s3getlocks s1commit s3getlocks s2commit +step s1begin: BEGIN; +step s1lock: LOCK TABLE part_drop_index_locking_subpart_child IN ACCESS SHARE MODE; +step s2begin: BEGIN; +step s2drop: DROP INDEX part_drop_index_locking_idx; +step s1select: SELECT * FROM part_drop_index_locking_subpart_child; +id +-- +(0 rows) + +step s3getlocks: + SELECT s.query, c.relname, l.mode, l.granted + FROM pg_locks l + JOIN pg_class c ON l.relation = c.oid + JOIN pg_stat_activity s ON l.pid = s.pid + WHERE c.relname LIKE 'part_drop_index_locking%' + ORDER BY s.query, c.relname, l.mode, l.granted; + +query |relname |mode |granted +----------------------------------------------------+---------------------------------------------+-------------------+------- +DROP INDEX part_drop_index_locking_idx; |part_drop_index_locking |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_idx; |part_drop_index_locking_idx |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_idx; |part_drop_index_locking_subpart |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_idx; |part_drop_index_locking_subpart_child |AccessExclusiveLock|f +SELECT * FROM part_drop_index_locking_subpart_child;|part_drop_index_locking_subpart_child |AccessShareLock |t +SELECT * FROM part_drop_index_locking_subpart_child;|part_drop_index_locking_subpart_child_id_idx |AccessShareLock |t +SELECT * FROM part_drop_index_locking_subpart_child;|part_drop_index_locking_subpart_child_id_idx1|AccessShareLock |t +(7 rows) + +step s1commit: COMMIT; +step s2drop: <... completed> +step s3getlocks: + SELECT s.query, c.relname, l.mode, l.granted + FROM pg_locks l + JOIN pg_class c ON l.relation = c.oid + JOIN pg_stat_activity s ON l.pid = s.pid + WHERE c.relname LIKE 'part_drop_index_locking%' + ORDER BY s.query, c.relname, l.mode, l.granted; + +query |relname |mode |granted +---------------------------------------+--------------------------------------------+-------------------+------- +DROP INDEX part_drop_index_locking_idx;|part_drop_index_locking |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_idx;|part_drop_index_locking_idx |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_idx;|part_drop_index_locking_subpart |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_idx;|part_drop_index_locking_subpart_child |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_idx;|part_drop_index_locking_subpart_child_id_idx|AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_idx;|part_drop_index_locking_subpart_id_idx |AccessExclusiveLock|t +(6 rows) + +step s2commit: COMMIT; + +starting permutation: s1begin s1lock s2begin s2dropsub s1select s3getlocks s1commit s3getlocks s2commit +step s1begin: BEGIN; +step s1lock: LOCK TABLE part_drop_index_locking_subpart_child IN ACCESS SHARE MODE; +step s2begin: BEGIN; +step s2dropsub: DROP INDEX part_drop_index_locking_subpart_idx; +step s1select: SELECT * FROM part_drop_index_locking_subpart_child; +id +-- +(0 rows) + +step s3getlocks: + SELECT s.query, c.relname, l.mode, l.granted + FROM pg_locks l + JOIN pg_class c ON l.relation = c.oid + JOIN pg_stat_activity s ON l.pid = s.pid + WHERE c.relname LIKE 'part_drop_index_locking%' + ORDER BY s.query, c.relname, l.mode, l.granted; + +query |relname |mode |granted +----------------------------------------------------+---------------------------------------------+-------------------+------- +DROP INDEX part_drop_index_locking_subpart_idx; |part_drop_index_locking_subpart |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_subpart_idx; |part_drop_index_locking_subpart_child |AccessExclusiveLock|f +DROP INDEX part_drop_index_locking_subpart_idx; |part_drop_index_locking_subpart_idx |AccessExclusiveLock|t +SELECT * FROM part_drop_index_locking_subpart_child;|part_drop_index_locking_subpart_child |AccessShareLock |t +SELECT * FROM part_drop_index_locking_subpart_child;|part_drop_index_locking_subpart_child_id_idx |AccessShareLock |t +SELECT * FROM part_drop_index_locking_subpart_child;|part_drop_index_locking_subpart_child_id_idx1|AccessShareLock |t +(6 rows) + +step s1commit: COMMIT; +step s2dropsub: <... completed> +step s3getlocks: + SELECT s.query, c.relname, l.mode, l.granted + FROM pg_locks l + JOIN pg_class c ON l.relation = c.oid + JOIN pg_stat_activity s ON l.pid = s.pid + WHERE c.relname LIKE 'part_drop_index_locking%' + ORDER BY s.query, c.relname, l.mode, l.granted; + +query |relname |mode |granted +-----------------------------------------------+---------------------------------------------+-------------------+------- +DROP INDEX part_drop_index_locking_subpart_idx;|part_drop_index_locking_subpart |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_subpart_idx;|part_drop_index_locking_subpart_child |AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_subpart_idx;|part_drop_index_locking_subpart_child_id_idx1|AccessExclusiveLock|t +DROP INDEX part_drop_index_locking_subpart_idx;|part_drop_index_locking_subpart_idx |AccessExclusiveLock|t +(4 rows) + +step s2commit: COMMIT; diff --git a/src/test/isolation/isolation_schedule b/src/test/isolation/isolation_schedule index 0dae483e82..8e87098150 100644 --- a/src/test/isolation/isolation_schedule +++ b/src/test/isolation/isolation_schedule @@ -90,6 +90,7 @@ test: predicate-hash test: predicate-gist test: predicate-gin test: partition-concurrent-attach +test: partition-drop-index-locking test: partition-key-update-1 test: partition-key-update-2 test: partition-key-update-3 diff --git a/src/test/isolation/specs/partition-drop-index-locking.spec b/src/test/isolation/specs/partition-drop-index-locking.spec new file mode 100644 index 0000000000..99e7f6cb64 --- /dev/null +++ b/src/test/isolation/specs/partition-drop-index-locking.spec @@ -0,0 +1,44 @@ +# Verify that DROP INDEX properly locks all downward sub-partitions +# and partitions before locking the indexes. + +setup +{ + CREATE TABLE part_drop_index_locking (id int) PARTITION BY RANGE(id); + CREATE TABLE part_drop_index_locking_subpart PARTITION OF part_drop_index_locking FOR VALUES FROM (1) TO (100) PARTITION BY RANGE(id); + CREATE TABLE part_drop_index_locking_subpart_child PARTITION OF part_drop_index_locking_subpart FOR VALUES FROM (1) TO (100); + CREATE INDEX part_drop_index_locking_idx ON part_drop_index_locking(id); + CREATE INDEX part_drop_index_locking_subpart_idx ON part_drop_index_locking_subpart(id); +} + +teardown +{ + DROP TABLE part_drop_index_locking; +} + +session s1 +step s1begin { BEGIN; } +step s1lock { LOCK TABLE part_drop_index_locking_subpart_child IN ACCESS SHARE MODE; } +step s1select { SELECT * FROM part_drop_index_locking_subpart_child; } +step s1commit { COMMIT; } + +session s2 +step s2begin { BEGIN; } +step s2drop { DROP INDEX part_drop_index_locking_idx; } +step s2dropsub { DROP INDEX part_drop_index_locking_subpart_idx; } +step s2commit { COMMIT; } + +session s3 +step s3getlocks { + SELECT s.query, c.relname, l.mode, l.granted + FROM pg_locks l + JOIN pg_class c ON l.relation = c.oid + JOIN pg_stat_activity s ON l.pid = s.pid + WHERE c.relname LIKE 'part_drop_index_locking%' + ORDER BY s.query, c.relname, l.mode, l.granted; +} + +# Run DROP INDEX on top partitioned table +permutation s1begin s1lock s2begin s2drop(s1commit) s1select s3getlocks s1commit s3getlocks s2commit + +# Run DROP INDEX on top sub-partition table +permutation s1begin s1lock s2begin s2dropsub(s1commit) s1select s3getlocks s1commit s3getlocks s2commit