test: fix data race caused by update global config (pingcap#17964)

Co-authored-by: pingcap-github-bot <sre-bot@pingcap.com>

config/config.go

@@ -880,6 +880,22 @@ func (c *Config) Valid() error {
 	return l.UnmarshalText([]byte(c.Log.Level))
 }
 
+// UpdateGlobal updates the global config, and provide a restore function that can be used to restore to the original.
+func UpdateGlobal(f func(conf *Config)) {
+	g := GetGlobalConfig()
+	newConf := *g
+	f(&newConf)
+	StoreGlobalConfig(&newConf)
+}
+
+// RestoreFunc gets a function that restore the config to the current value.
+func RestoreFunc() (restore func()) {
+	g := GetGlobalConfig()
+	return func() {
+		StoreGlobalConfig(g)
+	}
+}
+
 func hasRootPrivilege() bool {
 	return os.Geteuid() == 0
 }

ddl/db_change_test.go

@@ -92,7 +92,9 @@ func (s *testStateChangeSuiteBase) TearDownSuite(c *C) {
 
 // TestShowCreateTable tests the result of "show create table" when we are running "add index" or "add column".
 func (s *serialTestStateChangeSuite) TestShowCreateTable(c *C) {
-	config.GetGlobalConfig().Experimental.AllowsExpressionIndex = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.Experimental.AllowsExpressionIndex = true
+	})
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
 	tk.MustExec("create table t (id int)")
@@ -858,7 +860,9 @@ func (s *testStateChangeSuite) TestParallelAlterAddIndex(c *C) {
 }
 
 func (s *serialTestStateChangeSuite) TestParallelAlterAddExpressionIndex(c *C) {
-	config.GetGlobalConfig().Experimental.AllowsExpressionIndex = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.Experimental.AllowsExpressionIndex = true
+	})
 	sql1 := "ALTER TABLE t add index expr_index_b((b+1));"
 	sql2 := "CREATE INDEX expr_index_b ON t ((c+1));"
 	f := func(c *C, err1, err2 error) {

ddl/db_integration_test.go

@@ -1712,8 +1712,9 @@ func (s *testIntegrationSuite1) TestTreatOldVersionUTF8AsUTF8MB4(c *C) {
 		"  `b` varchar(10) CHARACTER SET ascii COLLATE ascii_bin DEFAULT NULL,\n" +
 		"  `c` varchar(10) CHARACTER SET utf8 COLLATE utf8_bin DEFAULT NULL\n" +
 		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
-
-	config.GetGlobalConfig().TreatOldVersionUTF8AsUTF8MB4 = false
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.TreatOldVersionUTF8AsUTF8MB4 = false
+	})
 	s.tk.MustExec("alter table t drop column c;") //  reload schema.
 	s.tk.MustGetErrCode("insert into t set a= x'f09f8c80'", errno.ErrTruncatedWrongValueForField)
 	s.tk.MustQuery("show create table t").Check(testkit.Rows("t CREATE TABLE `t` (\n" +
@@ -1730,7 +1731,9 @@ func (s *testIntegrationSuite1) TestTreatOldVersionUTF8AsUTF8MB4(c *C) {
 	tblInfo.Columns[0].Version = model.ColumnInfoVersion0
 	updateTableInfo(tblInfo)
 
-	config.GetGlobalConfig().TreatOldVersionUTF8AsUTF8MB4 = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.TreatOldVersionUTF8AsUTF8MB4 = true
+	})
 	s.tk.MustExec("alter table t add column c varchar(10);") //  load latest schema.
 	s.tk.MustExec("insert into t set a= x'f09f8c80'")
 	s.tk.MustQuery("show create table t").Check(testkit.Rows("t CREATE TABLE `t` (\n" +
@@ -1739,7 +1742,9 @@ func (s *testIntegrationSuite1) TestTreatOldVersionUTF8AsUTF8MB4(c *C) {
 		"  `c` varchar(10) DEFAULT NULL\n" +
 		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
 
-	config.GetGlobalConfig().TreatOldVersionUTF8AsUTF8MB4 = false
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.TreatOldVersionUTF8AsUTF8MB4 = false
+	})
 	s.tk.MustExec("alter table t drop column c;") //  reload schema.
 	s.tk.MustGetErrCode("insert into t set a= x'f09f8c80'", errno.ErrTruncatedWrongValueForField)
 	s.tk.MustQuery("show create table t").Check(testkit.Rows("t CREATE TABLE `t` (\n" +
@@ -1748,7 +1753,9 @@ func (s *testIntegrationSuite1) TestTreatOldVersionUTF8AsUTF8MB4(c *C) {
 		") ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin"))
 
 	// Test modify column charset.
-	config.GetGlobalConfig().TreatOldVersionUTF8AsUTF8MB4 = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.TreatOldVersionUTF8AsUTF8MB4 = true
+	})
 	s.tk.MustExec("alter table t modify column a varchar(10) character set utf8mb4") //  change column charset.
 	tbl = testGetTableByName(c, s.ctx, "test", "t")
 	c.Assert(tbl.Meta().Columns[0].Charset, Equals, charset.CharsetUTF8MB4)
@@ -1784,7 +1791,9 @@ func (s *testIntegrationSuite1) TestTreatOldVersionUTF8AsUTF8MB4(c *C) {
 		"  `b` varchar(20) CHARACTER SET ascii COLLATE ascii_bin DEFAULT NULL\n" +
 		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
 
-	config.GetGlobalConfig().TreatOldVersionUTF8AsUTF8MB4 = false
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.TreatOldVersionUTF8AsUTF8MB4 = false
+	})
 	s.tk.MustExec("alter table t change column b b varchar(30) character set ascii") // reload schema.
 	s.tk.MustGetErrCode("insert into t set a= x'f09f8c80'", errno.ErrTruncatedWrongValueForField)
 	s.tk.MustQuery("show create table t").Check(testkit.Rows("t CREATE TABLE `t` (\n" +
@@ -1793,11 +1802,15 @@ func (s *testIntegrationSuite1) TestTreatOldVersionUTF8AsUTF8MB4(c *C) {
 		") ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin"))
 
 	// Test for alter table convert charset
-	config.GetGlobalConfig().TreatOldVersionUTF8AsUTF8MB4 = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.TreatOldVersionUTF8AsUTF8MB4 = true
+	})
 	s.tk.MustExec("alter table t drop column b") // reload schema.
 	s.tk.MustExec("alter table t convert to charset utf8mb4;")
 
-	config.GetGlobalConfig().TreatOldVersionUTF8AsUTF8MB4 = false
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.TreatOldVersionUTF8AsUTF8MB4 = false
+	})
 	s.tk.MustExec("alter table t add column b varchar(50);") // reload schema.
 	s.tk.MustQuery("show create table t").Check(testkit.Rows("t CREATE TABLE `t` (\n" +
 		"  `a` varchar(20) DEFAULT NULL,\n" +
@@ -2044,7 +2057,9 @@ func (s *testIntegrationSuite3) TestParserIssue284(c *C) {
 }
 
 func (s *testIntegrationSuite7) TestAddExpressionIndex(c *C) {
-	config.GetGlobalConfig().Experimental.AllowsExpressionIndex = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.Experimental.AllowsExpressionIndex = true
+	})
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists t;")
@@ -2096,12 +2111,16 @@ func (s *testIntegrationSuite7) TestAddExpressionIndex(c *C) {
 	tk.MustExec("alter table t1 alter index ei_ab invisible;")
 
 	// Test experiment switch.
-	config.GetGlobalConfig().Experimental.AllowsExpressionIndex = false
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.Experimental.AllowsExpressionIndex = false
+	})
 	tk.MustGetErrMsg("create index d on t((a+1))", "[ddl:8200]Unsupported creating expression index without allow-expression-index in config")
 }
 
 func (s *testIntegrationSuite7) TestCreateExpressionIndexError(c *C) {
-	config.GetGlobalConfig().Experimental.AllowsExpressionIndex = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.Experimental.AllowsExpressionIndex = true
+	})
 
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
@@ -2263,7 +2282,9 @@ func (s *testIntegrationSuite3) TestCreateTableWithAutoIdCache(c *C) {
 }
 
 func (s *testIntegrationSuite4) TestAlterIndexVisibility(c *C) {
-	config.GetGlobalConfig().Experimental.AllowsExpressionIndex = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.Experimental.AllowsExpressionIndex = true
+	})
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("create database if not exists alter_index_test")
 	tk.MustExec("USE alter_index_test;")

ddl/db_partition_test.go

@@ -1138,7 +1138,9 @@ func (s *testIntegrationSuite4) TestExchangePartitionTableCompatiable(c *C) {
 }
 
 func (s *testIntegrationSuite7) TestExchangePartitionExpressIndex(c *C) {
-	config.GetGlobalConfig().Experimental.AllowsExpressionIndex = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.Experimental.AllowsExpressionIndex = true
+	})
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists pt1;")

ddl/db_test.go

@@ -264,7 +264,9 @@ func (s *testDBSuite2) TestAddUniqueIndexRollback(c *C) {
 }
 
 func (s *testSerialDBSuite) TestAddExpressionIndexRollback(c *C) {
-	config.GetGlobalConfig().Experimental.AllowsExpressionIndex = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.Experimental.AllowsExpressionIndex = true
+	})
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test_db")
 	tk.MustExec("drop table if exists t1")
@@ -4454,7 +4456,9 @@ func (s *testDBSuite2) TestTablesLockDelayClean(c *C) {
 
 	tk.MustExec("lock tables t1 write")
 	checkTableLock(c, tk.Se, "test", "t1", model.TableLockWrite)
-	config.GetGlobalConfig().DelayCleanTableLock = 100
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.DelayCleanTableLock = 100
+	})
 	var wg sync.WaitGroup
 	wg.Add(1)
 	var startTime time.Time
@@ -4468,7 +4472,9 @@ func (s *testDBSuite2) TestTablesLockDelayClean(c *C) {
 	wg.Wait()
 	c.Assert(time.Since(startTime).Seconds() > 0.1, IsTrue)
 	checkTableLock(c, tk.Se, "test", "t1", model.TableLockNone)
-	config.GetGlobalConfig().DelayCleanTableLock = 0
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.DelayCleanTableLock = 0
+	})
 }
 
 // TestConcurrentLockTables test concurrent lock/unlock tables.

ddl/ddl_test.go

@@ -94,14 +94,13 @@ func TestT(t *testing.T) {
 	ReorgWaitTimeout = 30 * time.Millisecond
 	batchInsertDeleteRangeSize = 2
 
-	cfg := config.GetGlobalConfig()
-	newCfg := *cfg
-	// Test for table lock.
-	newCfg.EnableTableLock = true
-	newCfg.Log.SlowThreshold = 10000
-	// Test for add/drop primary key.
-	newCfg.AlterPrimaryKey = true
-	config.StoreGlobalConfig(&newCfg)
+	config.UpdateGlobal(func(conf *config.Config) {
+		// Test for table lock.
+		conf.EnableTableLock = true
+		conf.Log.SlowThreshold = 10000
+		// Test for add/drop primary key.
+		conf.AlterPrimaryKey = true
+	})
 
 	testleak.BeforeTest()
 	TestingT(t)

ddl/serial_test.go

@@ -62,12 +62,10 @@ type testSerialSuite struct {
 func (s *testSerialSuite) SetUpSuite(c *C) {
 	session.SetSchemaLease(200 * time.Millisecond)
 	session.DisableStats4Test()
-
-	cfg := config.GetGlobalConfig()
-	newCfg := *cfg
-	// Test for add/drop primary key.
-	newCfg.AlterPrimaryKey = false
-	config.StoreGlobalConfig(&newCfg)
+	config.UpdateGlobal(func(conf *config.Config) {
+		// Test for add/drop primary key.
+		conf.AlterPrimaryKey = false
+	})
 
 	ddl.SetWaitTimeWhenErrorOccurred(1 * time.Microsecond)
 
@@ -95,15 +93,11 @@ func (s *testSerialSuite) TearDownSuite(c *C) {
 
 func (s *testSerialSuite) TestChangeMaxIndexLength(c *C) {
 	tk := testkit.NewTestKitWithInit(c, s.store)
-	cfg := config.GetGlobalConfig()
-	newCfg := *cfg
-	originalMaxIndexLen := cfg.MaxIndexLength
-	newCfg.MaxIndexLength = config.DefMaxOfMaxIndexLength
-	config.StoreGlobalConfig(&newCfg)
-	defer func() {
-		newCfg.MaxIndexLength = originalMaxIndexLen
-		config.StoreGlobalConfig(&newCfg)
-	}()
+
+	defer config.RestoreFunc()()
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.MaxIndexLength = config.DefMaxOfMaxIndexLength
+	})
 
 	tk.MustExec("create table t (c1 varchar(3073), index(c1)) charset = ascii;")
 	tk.MustExec(fmt.Sprintf("create table t1 (c1 varchar(%d), index(c1)) charset = ascii;", config.DefMaxOfMaxIndexLength))
@@ -132,15 +126,10 @@ func (s *testSerialSuite) TestPrimaryKey(c *C) {
 	tk.MustExec("create table primary_key_test1 (a int, b varchar(10), primary key(a))")
 	tk.MustExec("create table primary_key_test2 (a int, b varchar(10), primary key(b))")
 	tk.MustExec("create table primary_key_test3 (a int, b varchar(10))")
-	cfg := config.GetGlobalConfig()
-	newCfg := *cfg
-	orignalAlterPrimaryKey := newCfg.AlterPrimaryKey
-	newCfg.AlterPrimaryKey = true
-	config.StoreGlobalConfig(&newCfg)
-	defer func() {
-		newCfg.AlterPrimaryKey = orignalAlterPrimaryKey
-		config.StoreGlobalConfig(&newCfg)
-	}()
+	defer config.RestoreFunc()()
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.AlterPrimaryKey = true
+	})
 
 	_, err = tk.Exec("alter table primary_key_test1 drop primary key")
 	c.Assert(err.Error(), Equals, "[ddl:8200]Unsupported drop primary key when the table's pkIsHandle is true")
@@ -150,8 +139,9 @@ func (s *testSerialSuite) TestPrimaryKey(c *C) {
 
 	// for "drop index `primary` on ..." syntax
 	tk.MustExec("create table primary_key_test4 (a int, b varchar(10), primary key(a))")
-	newCfg.AlterPrimaryKey = false
-	config.StoreGlobalConfig(&newCfg)
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.AlterPrimaryKey = false
+	})
 	_, err = tk.Exec("drop index `primary` on primary_key_test4")
 	c.Assert(err.Error(), Equals, "[ddl:8200]Unsupported drop primary key when alter-primary-key is false")
 	// for the index name is `primary`
@@ -814,13 +804,10 @@ func (s *testSerialSuite) TestTableLocksEnable(c *C) {
 	tk.MustExec("create table t1 (a int)")
 
 	// Test for enable table lock config.
-	cfg := config.GetGlobalConfig()
-	newCfg := *cfg
-	newCfg.EnableTableLock = false
-	config.StoreGlobalConfig(&newCfg)
-	defer func() {
-		config.StoreGlobalConfig(cfg)
-	}()
+	defer config.RestoreFunc()()
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.EnableTableLock = false
+	})
 
 	tk.MustExec("lock tables t1 write")
 	checkTableLock(c, tk.Se, "test", "t1", model.TableLockNone)
@@ -898,11 +885,15 @@ func (s *testSerialSuite) TestAutoRandom(c *C) {
 	assertPKIsNotHandle("create table t (a bigint auto_random(3), b int, c char, primary key (a, c))", "a")
 
 	// PKIsNotHandle: table is created when alter-primary-key = true.
-	config.GetGlobalConfig().AlterPrimaryKey = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.AlterPrimaryKey = true
+	})
 	assertPKIsNotHandle("create table t (a bigint auto_random(3) primary key, b int)", "a")
 	assertPKIsNotHandle("create table t (a bigint auto_random(3) primary key, b int)", "a")
 	assertPKIsNotHandle("create table t (a int, b bigint auto_random(3) primary key)", "b")
-	config.GetGlobalConfig().AlterPrimaryKey = false
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.AlterPrimaryKey = false
+	})
 
 	// Can not set auto_random along with auto_increment.
 	assertWithAutoInc("create table t (a bigint auto_random(3) primary key auto_increment)")
@@ -1223,15 +1214,10 @@ func (s *testSerialSuite) TestInvisibleIndex(c *C) {
 	tk.MustExec("insert into t values (11, 12)")
 	tk.MustQuery("select * from t").Check(testkit.Rows("1 2", "3 4", "5 6", "7 8", "9 10", "11 12"))
 
-	cfg := config.GetGlobalConfig()
-	newCfg := *cfg
-	orignalAlterPrimaryKey := newCfg.AlterPrimaryKey
-	newCfg.AlterPrimaryKey = true
-	config.StoreGlobalConfig(&newCfg)
-	defer func() {
-		newCfg.AlterPrimaryKey = orignalAlterPrimaryKey
-		config.StoreGlobalConfig(&newCfg)
-	}()
+	defer config.RestoreFunc()()
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.AlterPrimaryKey = true
+	})
 
 	// Limitation: Primary key cannot be invisible index
 	tk.MustGetErrCode("create table t1 (a int, primary key (a) invisible)", errno.ErrPKIndexCantBeInvisible)
@@ -1291,7 +1277,9 @@ func (s *testSerialSuite) TestCreateClusteredIndex(c *C) {
 	c.Assert(err, IsNil)
 	c.Assert(tbl.Meta().IsCommonHandle, IsFalse)
 
-	config.GetGlobalConfig().AlterPrimaryKey = true
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.AlterPrimaryKey = true
+	})
 	tk.MustExec("CREATE TABLE t5 (a varchar(255) primary key, b int)")
 	tk.MustExec("CREATE TABLE t6 (a int, b int, c int, primary key (a, b))")
 	is = domain.GetDomain(ctx).InfoSchema()
@@ -1301,7 +1289,9 @@ func (s *testSerialSuite) TestCreateClusteredIndex(c *C) {
 	tbl, err = is.TableByName(model.NewCIStr("test"), model.NewCIStr("t6"))
 	c.Assert(err, IsNil)
 	c.Assert(tbl.Meta().IsCommonHandle, IsFalse)
-	config.GetGlobalConfig().AlterPrimaryKey = false
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.AlterPrimaryKey = false
+	})
 
 	tk.MustExec("CREATE TABLE t21 like t2")
 	tk.MustExec("CREATE TABLE t31 like t3")

executor/executor_pkg_test.go

@@ -255,12 +255,11 @@ func assertEqualStrings(c *C, got []field, expect []string) {
 }
 
 func (s *testExecSerialSuite) TestSortSpillDisk(c *C) {
-	originCfg := config.GetGlobalConfig()
-	newConf := *originCfg
-	newConf.OOMUseTmpStorage = true
-	newConf.MemQuotaQuery = 1
-	config.StoreGlobalConfig(&newConf)
-	defer config.StoreGlobalConfig(originCfg)
+	defer config.RestoreFunc()()
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.OOMUseTmpStorage = true
+		conf.MemQuotaQuery = 1
+	})
 
 	ctx := mock.NewContext()
 	ctx.GetSessionVars().InitChunkSize = variable.DefMaxChunkSize