From c0c2f75ae0b4fa3e6959a1157d400e316f40ada0 Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Mon, 23 Sep 2019 15:20:37 +0900 Subject: [PATCH v2 1/3] Fix failure with lock mode used for custom relation options Relation options can use a custom lock mode since 47167b7, which has lowered the lock available for some autovacuum parameters, however it forgot to consider custom relation options. This causes failures with ALTER TABLE SET when changing a custom relation option, as its lock is not defined. The existing APIs to define a custom reloption does not allow to define a custom lock mode, so enforce its initialization to AccessExclusiveMode which is safe enough in all cases. An upcoming patch will extend the existing APIs to allow a custom lock mode to be defined. The problem can be reproduced with bloom indexes, so add a test there. Reported-by: Nikolay Sharplov Analyzed-by: Thomas Munro, Michael Paquier Author: Michael Paquier Reviewed-by: Kuntal Ghosh Discussion: https://postgr.es/m/20190920013831.GD1844@paquier.xyz Backpatch-through: 9.6 --- contrib/bloom/expected/bloom.out | 1 + contrib/bloom/sql/bloom.sql | 1 + src/backend/access/common/reloptions.c | 7 +++++++ 3 files changed, 9 insertions(+) diff --git a/contrib/bloom/expected/bloom.out b/contrib/bloom/expected/bloom.out index 5ab9e34f82..dae12a7d3e 100644 --- a/contrib/bloom/expected/bloom.out +++ b/contrib/bloom/expected/bloom.out @@ -5,6 +5,7 @@ CREATE TABLE tst ( ); INSERT INTO tst SELECT i%10, substr(md5(i::text), 1, 1) FROM generate_series(1,2000) i; CREATE INDEX bloomidx ON tst USING bloom (i, t) WITH (col1 = 3); +ALTER INDEX bloomidx SET (length=80); SET enable_seqscan=on; SET enable_bitmapscan=off; SET enable_indexscan=off; diff --git a/contrib/bloom/sql/bloom.sql b/contrib/bloom/sql/bloom.sql index 32755f2b1a..4733e1e705 100644 --- a/contrib/bloom/sql/bloom.sql +++ b/contrib/bloom/sql/bloom.sql @@ -7,6 +7,7 @@ CREATE TABLE tst ( INSERT INTO tst SELECT i%10, substr(md5(i::text), 1, 1) FROM generate_series(1,2000) i; CREATE INDEX bloomidx ON tst USING bloom (i, t) WITH (col1 = 3); +ALTER INDEX bloomidx SET (length=80); SET enable_seqscan=on; SET enable_bitmapscan=off; diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c index 20f4ed3c38..b59e606771 100644 --- a/src/backend/access/common/reloptions.c +++ b/src/backend/access/common/reloptions.c @@ -659,6 +659,13 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc) newoption->namelen = strlen(name); newoption->type = type; + /* + * Set the default lock mode for this option. There is no actual way + * for a module to enforce it when declaring a custom relation option, + * so just use the highest level, which is safe for all cases. + */ + newoption->lockmode = AccessExclusiveLock; + MemoryContextSwitchTo(oldcxt); return newoption; -- 2.23.0