Forward port r127 from branches/5.0:

Fixed a bug #16229 MySQL/InnoDB uses full explicit table locks 
in trigger processing. Take a InnoDB table lock only if user has explicitly
requested a table lock. Added some additional comments to store_lock() and 
external_lock(). Added test cases for a bug. Fixed some code style errors.

handler/ha_innodb.cc

@@ -1004,6 +1004,7 @@ innobase_query_caching_of_table_permitted(
 		mutex_enter(&kernel_mutex);
 		trx_print(stderr, trx, 1024);
 		mutex_exit(&kernel_mutex);
+		ut_error;
 	}
 
 	innobase_release_stat_resources(trx);
@@ -6354,14 +6355,17 @@ ha_innobase::external_lock(
 		TABLES if AUTOCOMMIT=1. It does not make much sense to acquire
 		an InnoDB table lock if it is released immediately at the end
 		of LOCK TABLES, and InnoDB's table locks in that case cause
-		VERY easily deadlocks. We do not set InnoDB table locks when
-		MySQL sets them at the start of a stored procedure call
-		(MySQL does have thd->in_lock_tables TRUE there). */
+		VERY easily deadlocks. 
+
+		We do not set InnoDB table locks if user has not explicitly
+		requested a table lock. Note that thd->in_lock_tables
+		can  be TRUE on some cases e.g. at the start of a stored
+		procedure call (SQLCOM_CALL). */
 
 		if (prebuilt->select_lock_type != LOCK_NONE) {
 
 			if (thd->in_lock_tables &&
-			    thd->lex->sql_command != SQLCOM_CALL &&
+			    thd->lex->sql_command == SQLCOM_LOCK_TABLES &&
 			    thd->variables.innodb_table_locks &&
 			    (thd->options & OPTION_NOT_AUTOCOMMIT)) {
 
@@ -6844,7 +6848,7 @@ ha_innobase::store_lock(
 
 	} else if (lock_type != TL_IGNORE) {
 
-	        /* We set possible LOCK_X value in external_lock, not yet
+		/* We set possible LOCK_X value in external_lock, not yet
 		here even if this would be SELECT ... FOR UPDATE */
 
 		prebuilt->select_lock_type = LOCK_NONE;
@@ -6853,7 +6857,7 @@ ha_innobase::store_lock(
 
 	if (lock_type != TL_IGNORE && lock.type == TL_UNLOCK) {
 
-                /* Starting from 5.0.7, we weaken also the table locks
+		/* Starting from 5.0.7, we weaken also the table locks
 		set at the start of a MySQL stored procedure call, just like
 		we weaken the locks set at the start of an SQL statement.
 		MySQL does set thd->in_lock_tables TRUE there, but in reality
@@ -6876,26 +6880,36 @@ ha_innobase::store_lock(
 			lock_type = TL_READ_NO_INSERT;
 		}
 
-    		/* If we are not doing a LOCK TABLE or DISCARD/IMPORT
-		TABLESPACE or TRUNCATE TABLE, then allow multiple writers */
+		/* If we are not doing a LOCK TABLE, DISCARD/IMPORT
+		TABLESPACE or TRUNCATE TABLE then allow multiple 
+		writers. Note that ALTER TABLE uses a TL_WRITE_ALLOW_READ
+		< TL_WRITE_CONCURRENT_INSERT.
+
+		We especially allow multiple writers if MySQL is at the 
+		start of a stored procedure call (SQLCOM_CALL) 
+		(MySQL does have thd->in_lock_tables TRUE there). */
 
-    		if ((lock_type >= TL_WRITE_CONCURRENT_INSERT &&
-	 	    lock_type <= TL_WRITE)
+    		if ((lock_type >= TL_WRITE_CONCURRENT_INSERT 
+		    && lock_type <= TL_WRITE)
 		    && (!thd->in_lock_tables
-		        || thd->lex->sql_command == SQLCOM_CALL)
+			|| thd->lex->sql_command == SQLCOM_CALL)
 		    && !thd->tablespace_op
 		    && thd->lex->sql_command != SQLCOM_TRUNCATE
 		    && thd->lex->sql_command != SQLCOM_OPTIMIZE
-                    && thd->lex->sql_command != SQLCOM_CREATE_TABLE) {
+		    && thd->lex->sql_command != SQLCOM_CREATE_TABLE) {
 
-      			lock_type = TL_WRITE_ALLOW_WRITE;
+			lock_type = TL_WRITE_ALLOW_WRITE;
       		}
 
 		/* In queries of type INSERT INTO t1 SELECT ... FROM t2 ...
 		MySQL would use the lock TL_READ_NO_INSERT on t2, and that
 		would conflict with TL_WRITE_ALLOW_WRITE, blocking all inserts
 		to t2. Convert the lock to a normal read lock to allow
-		concurrent inserts to t2. */
+		concurrent inserts to t2. 
+
+		We especially allow concurrent inserts if MySQL is at the 
+		start of a stored procedure call (SQLCOM_CALL) 
+		(MySQL does have thd->in_lock_tables TRUE there). */
       		
 		if (lock_type == TL_READ_NO_INSERT
 		    && (!thd->in_lock_tables
@@ -6904,10 +6918,10 @@ ha_innobase::store_lock(
 			lock_type = TL_READ;
 		}
 		
- 		lock.type = lock_type;
-  	}
+		lock.type = lock_type;
+	}
 
-  	*to++= &lock;
+	*to++= &lock;
 
 	return(to);
 }

mysql-test/innodb.result

@@ -3180,3 +3180,61 @@ a	hex(b)
 7	D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B2
 update t1 set b = 'three' where a = 6;
 drop table t1;
+create table t1(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+insert into t1(a) values (1),(2),(3);
+commit;
+set autocommit = 0;
+update t1 set b = 5 where a = 2;
+create trigger t1t before insert on t1 for each row begin set NEW.b = NEW.a * 10 + 5, NEW.c = NEW.a / 10; end |
+set autocommit = 0;
+insert into t1(a) values (10),(20),(30),(40),(50),(60),(70),(80),(90),(100),
+(11),(21),(31),(41),(51),(61),(71),(81),(91),(101),
+(12),(22),(32),(42),(52),(62),(72),(82),(92),(102),
+(13),(23),(33),(43),(53),(63),(73),(83),(93),(103),
+(14),(24),(34),(44),(54),(64),(74),(84),(94),(104);
+commit;
+commit;
+drop trigger t1t;
+drop table t1;
+create table t1(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+create table t2(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+create table t3(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+create table t4(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+create table t5(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+insert into t1(a) values (1),(2),(3);
+insert into t2(a) values (1),(2),(3);
+insert into t3(a) values (1),(2),(3);
+insert into t4(a) values (1),(2),(3);
+insert into t3(a) values (5),(7),(8);
+insert into t4(a) values (5),(7),(8);
+insert into t5(a) values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12);
+create trigger t1t before insert on t1 for each row begin 
+INSERT INTO t2 SET a = NEW.a;
+end |
+create trigger t2t before insert on t2 for each row begin
+DELETE FROM t3 WHERE a = NEW.a;
+end |
+create trigger t3t before delete on t3 for each row begin  
+UPDATE t4 SET b = b + 1 WHERE a = OLD.a;
+end |
+create trigger t4t before update on t4 for each row begin
+UPDATE t5 SET b = b + 1 where a = NEW.a;
+end |
+commit;
+set autocommit = 0;
+update t1 set b = b + 5 where a = 1;
+update t2 set b = b + 5 where a = 1;
+update t3 set b = b + 5 where a = 1;
+update t4 set b = b + 5 where a = 1;
+insert into t5(a) values(20);
+set autocommit = 0;
+insert into t1(a) values(7);
+insert into t2(a) values(8);
+delete from t2 where a = 3;
+update t4 set b = b + 1 where a = 3;
+commit;
+drop trigger t1t;
+drop trigger t2t;
+drop trigger t3t;
+drop trigger t4t;
+drop table t1, t2, t3, t4, t5;

mysql-test/innodb.test

@@ -2047,3 +2047,93 @@ insert into t1 values(7,_utf8 0xD0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1D0B1
 select a,hex(b) from t1 order by b;
 update t1 set b = 'three' where a = 6;
 drop table t1;
+
+#
+# Test case for bug #16229: MySQL/InnoDB uses full explicit table locks in trigger processing
+#
+
+connect (a,localhost,root,,);
+connect (b,localhost,root,,);
+connection a;
+create table t1(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+insert into t1(a) values (1),(2),(3);
+commit;
+connection b;
+set autocommit = 0;
+update t1 set b = 5 where a = 2;
+connection a;
+delimiter |;
+create trigger t1t before insert on t1 for each row begin set NEW.b = NEW.a * 10 + 5, NEW.c = NEW.a / 10; end |
+delimiter ;|
+set autocommit = 0;
+connection a;
+insert into t1(a) values (10),(20),(30),(40),(50),(60),(70),(80),(90),(100),
+(11),(21),(31),(41),(51),(61),(71),(81),(91),(101),
+(12),(22),(32),(42),(52),(62),(72),(82),(92),(102),
+(13),(23),(33),(43),(53),(63),(73),(83),(93),(103),
+(14),(24),(34),(44),(54),(64),(74),(84),(94),(104);
+connection b;
+commit;
+connection a;
+commit;
+drop trigger t1t;
+drop table t1;
+disconnect a;
+disconnect b;
+#
+# Another trigger test
+#
+connect (a,localhost,root,,);
+connect (b,localhost,root,,);
+connection a;
+create table t1(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+create table t2(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+create table t3(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+create table t4(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+create table t5(a int not null, b int, c int, d int, primary key(a)) engine=innodb;
+insert into t1(a) values (1),(2),(3);
+insert into t2(a) values (1),(2),(3);
+insert into t3(a) values (1),(2),(3);
+insert into t4(a) values (1),(2),(3);
+insert into t3(a) values (5),(7),(8);
+insert into t4(a) values (5),(7),(8);
+insert into t5(a) values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12);
+
+delimiter |;
+create trigger t1t before insert on t1 for each row begin 
+    INSERT INTO t2 SET a = NEW.a;
+end |
+
+create trigger t2t before insert on t2 for each row begin
+    DELETE FROM t3 WHERE a = NEW.a;
+end |
+
+create trigger t3t before delete on t3 for each row begin  
+    UPDATE t4 SET b = b + 1 WHERE a = OLD.a;
+end |
+
+create trigger t4t before update on t4 for each row begin
+    UPDATE t5 SET b = b + 1 where a = NEW.a;
+end |
+delimiter ;|
+commit;
+set autocommit = 0;
+update t1 set b = b + 5 where a = 1;
+update t2 set b = b + 5 where a = 1;
+update t3 set b = b + 5 where a = 1;
+update t4 set b = b + 5 where a = 1;
+insert into t5(a) values(20);
+connection b;
+set autocommit = 0;
+insert into t1(a) values(7);
+insert into t2(a) values(8);
+delete from t2 where a = 3;
+update t4 set b = b + 1 where a = 3;
+commit;
+drop trigger t1t;
+drop trigger t2t;
+drop trigger t3t;
+drop trigger t4t;
+drop table t1, t2, t3, t4, t5;
+disconnect a;
+disconnect b;