Additional test coverage for

Bug#30977 Concurrent statement using stored function and
          DROP FUNCTION breaks SBR
Bug#48246 assert in close_thread_table

mysql-test/r/sp-lock.result

@@ -693,5 +693,47 @@ set @@session.max_sp_recursion_depth=default;
 # --> connection con3
 # --> connection default
 #
+# SHOW CREATE PROCEDURE p1 called from p1, after p1 was altered
+#
+# We are just covering the existing behaviour with tests. The
+# results are not necessarily correct."
+#
+CREATE PROCEDURE p1()
+BEGIN
+SELECT get_lock("test", 10);
+SHOW CREATE PROCEDURE p1;
+END|
+# Connection default
+SELECT get_lock("test", 10);
+get_lock("test", 10)
+1
+# Connection 2
+# Will halt before executing SHOW CREATE PROCEDURE p1
+# Sending:
+CALL p1();
+# Connection 3
+# Alter p1
+DROP PROCEDURE p1;
+CREATE PROCEDURE p1() BEGIN END;
+# Connection default
+# Resume CALL p1, now with new p1
+SELECT release_lock("test");
+release_lock("test")
+1
+# Connection 2
+# Reaping: CALL p1()
+get_lock("test", 10)
+1
+Procedure	sql_mode	Create Procedure	character_set_client	collation_connection	Database Collation
+p1		CREATE DEFINER=`root`@`localhost` PROCEDURE `p1`()
+BEGIN
+SELECT get_lock("test", 10);
+SHOW CREATE PROCEDURE p1;
+END	latin1	latin1_swedish_ci	latin1_swedish_ci
+# Connection 3
+# Connection 2
+# Connection default;
+DROP PROCEDURE p1;
+#
 # End of 5.5 tests
 #

mysql-test/r/sp_sync.result

@@ -1,23 +1,94 @@
 Tests of syncronization of stored procedure execution.
+SET DEBUG_SYNC= 'RESET';
 #
-# Bug#48157: crash in Item_field::used_tables
+# Bug #30977 Concurrent statement using stored function and
+#            DROP FUNCTION breaks SBR
 #
-CREATE TABLE t1 AS SELECT 1 AS a, 1 AS b;
+# A stored routine could change after dispatch_command()
-CREATE TABLE t2 AS SELECT 1 AS a, 1 AS b;
+# but before a MDL lock is taken. This must be noticed and the
-CREATE PROCEDURE p1()
+# sp cache flushed so the correct version can be loaded.
-BEGIN
+#
-UPDATE t1 JOIN t2 USING( a, b ) SET t1.b = 1, t2.b = 1;
+# Connection default
-END|
+CREATE FUNCTION f1() RETURNS INT RETURN 1;
-LOCK TABLES t1 WRITE, t2 WRITE;
+# Get f1 cached
-SET DEBUG_SYNC = 'multi_update_reopen_tables SIGNAL parked WAIT_FOR go';
+SELECT f1();
+f1()
+1
+# Then start executing it again...
+SET DEBUG_SYNC= 'before_execute_sql_command SIGNAL before WAIT_FOR changed';
+# Sending:
+SELECT f1();
+# Connection 2
+SET DEBUG_SYNC= 'now WAIT_FOR before';
+# ... but before f1 is locked, change it.
+DROP FUNCTION f1;
+CREATE FUNCTION f1() RETURNS INT RETURN 2;
+SET DEBUG_SYNC= 'now SIGNAL changed';
+# Connection default
+# We should now get '2' and not '1'.
+# Reaping: SELECT f1()
+f1()
+2
+DROP FUNCTION f1;
+SET DEBUG_SYNC= 'RESET';
+#
+# Field translation items must be cleared in case of back-offs
+# for queries that use Information Schema tables. Otherwise 
+# memory allocated in fix_fields() for views may end up referring
+# to freed memory.
+#
+DROP FUNCTION IF EXISTS f1;
+# Connection default
+CREATE FUNCTION f1() RETURNS INT RETURN 0;
+# Connection con2
+SET DEBUG_SYNC= 'after_wait_locked_pname SIGNAL locked WAIT_FOR issued';
+# con2 will now have an x-lock on f1
+# Sending:
+ALTER FUNCTION f1 COMMENT 'comment';
+# Connection default
+SET DEBUG_SYNC= 'now WAIT_FOR locked';
+# This query will block due to the x-lock on f1 and back-off
+SHOW OPEN TABLES WHERE f1()=0;
+# Connection con3
+# Check that the IS query is blocked before releasing the x-lock
+SET DEBUG_SYNC= 'now SIGNAL issued';
+# Connection default
+# Reaping: ALTER FUNCTION f1 COMMENT 'comment'
+DROP FUNCTION f1;
+SET DEBUG_SYNC= 'RESET';
+#
+# Bug #48246 assert in close_thread_table
+#
+CREATE TABLE t1 (a INTEGER);
+CREATE FUNCTION f1(b INTEGER) RETURNS INTEGER RETURN 1;
+CREATE PROCEDURE p1() SELECT COUNT(f1(a)) FROM t1;
+INSERT INTO t1 VALUES(1), (2);
+# Connection 2
 CALL p1();
-DROP TABLE t1, t2;
+COUNT(f1(a))
-SET DEBUG_SYNC = 'now WAIT_FOR parked';
+2
-CREATE TABLE t1 AS SELECT 1 AS a, 1 AS b;
+# Connection default
-CREATE TABLE t2 AS SELECT 1 AS a, 1 AS b;
+SET DEBUG_SYNC= 'after_open_table_mdl_shared SIGNAL locked WAIT_FOR called';
-SET DEBUG_SYNC = 'now SIGNAL go';
+# Sending:
-# Without the DEBUG_SYNC supplied in the same patch as this test in the 
+CREATE TABLE t1 (a INTEGER);
-# code, this test statement will hang.
+# Connection 2
-DROP TABLE t1, t2;
+SET DEBUG_SYNC= 'now WAIT_FOR locked';
+SET DEBUG_SYNC= 'before_open_table_wait_refresh SIGNAL called WAIT_FOR created';
+# This call used to cause an assertion. MDL locking conflict will
+# cause back-off and retry. A variable indicating if a prelocking list
+# exists, used to be not reset properly causing an eventual assert.
+# Sending:
+CALL p1();
+# Connection default
+# Reaping: CREATE TABLE t1 (a INTEGER)
+ERROR 42S01: Table 't1' already exists
+SET DEBUG_SYNC= 'now SIGNAL created';
+# Connection 2
+# Reaping: CALL p1()
+COUNT(f1(a))
+2
+# Connection default
 DROP PROCEDURE p1;
-SET DEBUG_SYNC = 'RESET';
+DROP FUNCTION f1;
+DROP TABLE t1;
+SET DEBUG_SYNC= 'RESET';

mysql-test/t/disabled.def

@@ -11,7 +11,6 @@
 ##############################################################################
 kill                     : Bug#37780 2008-12-03 HHunger need some changes to be robust enough for pushbuild.
 query_cache_28249        : Bug#43861 2009-03-25 main.query_cache_28249 fails sporadically
-sp_sync                  : Bug#48157 2010-02-06 5.5-m3 demands a differnt solution
 innodb-autoinc           : Bug#49267 2009-12-02 test fails on windows because of different case mode
 innodb                   : Bug#49396 2009-12-03 test fails in embedded mode
 plugin_load              : Bug#42144 2009-12-21 alik plugin_load fails

mysql-test/t/sp-lock.test

@@ -893,6 +893,68 @@ disconnect con3;
 --source include/wait_until_disconnected.inc
 --echo # --> connection default
 connection default;
+
+
+--echo #
+--echo # SHOW CREATE PROCEDURE p1 called from p1, after p1 was altered
+--echo #
+--echo # We are just covering the existing behaviour with tests. The
+--echo # results are not necessarily correct."
+--echo #
+
+delimiter |;
+CREATE PROCEDURE p1()
+BEGIN
+  SELECT get_lock("test", 10);
+  SHOW CREATE PROCEDURE p1;
+END|
+delimiter ;|
+
+connect (con2, localhost, root);
+connect (con3, localhost, root);
+
+--echo # Connection default
+connection default;
+SELECT get_lock("test", 10);
+
+--echo # Connection 2
+connection con2;
+--echo # Will halt before executing SHOW CREATE PROCEDURE p1
+--echo # Sending:
+--send CALL p1()
+
+--echo # Connection 3
+connection con3;
+let $wait_condition=SELECT COUNT(*)=1 FROM information_schema.processlist 
+  WHERE state='User lock' and info='SELECT get_lock("test", 10)';
+--source include/wait_condition.inc
+--echo # Alter p1
+DROP PROCEDURE p1;
+CREATE PROCEDURE p1() BEGIN END;
+
+--echo # Connection default
+connection default;
+--echo # Resume CALL p1, now with new p1
+SELECT release_lock("test");
+
+--echo # Connection 2
+connection con2;
+--echo # Reaping: CALL p1()
+--reap
+
+--echo # Connection 3
+connection con3;
+disconnect con3;
+--source include/wait_until_disconnected.inc
+--echo # Connection 2
+connection con2;
+disconnect con2;
+--source include/wait_until_disconnected.inc
+--echo # Connection default;
+connection default;
+DROP PROCEDURE p1;
+
+
 --echo #
 --echo # End of 5.5 tests
 --echo #

mysql-test/t/sp_sync.test

@@ -5,54 +5,156 @@
 
 --source include/have_debug_sync.inc
 
+# Save the initial number of concurrent sessions.
+--source include/count_sessions.inc
+
+# Clean up resources used in this test case.
+--disable_warnings
+SET DEBUG_SYNC= 'RESET';
+--enable_warnings
+
 --echo #
---echo # Bug#48157: crash in Item_field::used_tables
+--echo # Bug #30977 Concurrent statement using stored function and
+--echo #            DROP FUNCTION breaks SBR
+--echo #
+--echo # A stored routine could change after dispatch_command()
+--echo # but before a MDL lock is taken. This must be noticed and the
+--echo # sp cache flushed so the correct version can be loaded.
 --echo #
 
-CREATE TABLE t1 AS SELECT 1 AS a, 1 AS b;
+connect (con2, localhost, root);
-CREATE TABLE t2 AS SELECT 1 AS a, 1 AS b;
 
-DELIMITER |;
+--echo # Connection default
-
+connection default;
-CREATE PROCEDURE p1()
+CREATE FUNCTION f1() RETURNS INT RETURN 1;
-BEGIN
+--echo # Get f1 cached
-   UPDATE t1 JOIN t2 USING( a, b ) SET t1.b = 1, t2.b = 1;
+SELECT f1();
-END|
+--echo # Then start executing it again...
-
+SET DEBUG_SYNC= 'before_execute_sql_command SIGNAL before WAIT_FOR changed';
-DELIMITER ;|
+--echo # Sending:
-
+--send SELECT f1()
-connect (con1,localhost,root,,);
-connect (con2,localhost,root,,);
-
-connection con1;
-LOCK TABLES t1 WRITE, t2 WRITE;
 
+--echo # Connection 2
 connection con2;
-LET $ID= `select connection_id()`;
+SET DEBUG_SYNC= 'now WAIT_FOR before';
-SET DEBUG_SYNC = 'multi_update_reopen_tables SIGNAL parked WAIT_FOR go';
+--echo # ... but before f1 is locked, change it.
---send CALL p1()
+DROP FUNCTION f1;
+CREATE FUNCTION f1() RETURNS INT RETURN 2;
+SET DEBUG_SYNC= 'now SIGNAL changed';
 
-connection con1;
+--echo # Connection default
-let $wait_condition= SELECT 1 FROM information_schema.processlist WHERE ID = $ID AND
+--echo # We should now get '2' and not '1'.
-state = "Waiting for table";
+connection default;
---source include/wait_condition.inc
+--echo # Reaping: SELECT f1()
-DROP TABLE t1, t2;
-SET DEBUG_SYNC = 'now WAIT_FOR parked';
-CREATE TABLE t1 AS SELECT 1 AS a, 1 AS b;
-CREATE TABLE t2 AS SELECT 1 AS a, 1 AS b;
-SET DEBUG_SYNC = 'now SIGNAL go';
-
-connection con2;
 --reap
 
-disconnect con1;
 disconnect con2;
+DROP FUNCTION f1;
+SET DEBUG_SYNC= 'RESET';
+
+--echo #
+--echo # Field translation items must be cleared in case of back-offs
+--echo # for queries that use Information Schema tables. Otherwise 
+--echo # memory allocated in fix_fields() for views may end up referring
+--echo # to freed memory.
+--echo #
+
+--disable_warnings
+DROP FUNCTION IF EXISTS f1;
+--enable_warnings
+
+connect (con2, localhost, root);
+connect (con3, localhost, root);
+
+--echo # Connection default
 connection default;
+CREATE FUNCTION f1() RETURNS INT RETURN 0;
 
---echo # Without the DEBUG_SYNC supplied in the same patch as this test in the 
+--echo # Connection con2
---echo # code, this test statement will hang.
+connection con2;
-DROP TABLE t1, t2;
+SET DEBUG_SYNC= 'after_wait_locked_pname SIGNAL locked WAIT_FOR issued';
+--echo # con2 will now have an x-lock on f1
+--echo # Sending:
+--send ALTER FUNCTION f1 COMMENT 'comment'
+
+--echo # Connection default
+connection default;
+SET DEBUG_SYNC= 'now WAIT_FOR locked';
+--disable_result_log
+--echo # This query will block due to the x-lock on f1 and back-off
+--send SHOW OPEN TABLES WHERE f1()=0
+
+--echo # Connection con3
+connection con3;
+let $wait_condition= SELECT COUNT(*)= 1 FROM information_schema.processlist
+  WHERE state= 'Waiting for table' 
+  AND info='SHOW OPEN TABLES WHERE f1()=0';
+--source include/wait_condition.inc
+--echo # Check that the IS query is blocked before releasing the x-lock
+SET DEBUG_SYNC= 'now SIGNAL issued';
+
+--echo # Connection default
+connection default;
+--echo # Reaping: ALTER FUNCTION f1 COMMENT 'comment'
+--reap
+--enable_result_log
+DROP FUNCTION f1;
+SET DEBUG_SYNC= 'RESET';
+disconnect con2;
+disconnect con3;
+
+
+--echo #
+--echo # Bug #48246 assert in close_thread_table
+--echo #
+
+CREATE TABLE t1 (a INTEGER);
+CREATE FUNCTION f1(b INTEGER) RETURNS INTEGER RETURN 1;
+CREATE PROCEDURE p1() SELECT COUNT(f1(a)) FROM t1;
+
+INSERT INTO t1 VALUES(1), (2);
+
+--echo # Connection 2
+connect (con2, localhost, root);
+CALL p1();
+
+--echo # Connection default
+connection default;
+SET DEBUG_SYNC= 'after_open_table_mdl_shared SIGNAL locked WAIT_FOR called';
+--echo # Sending:
+--send CREATE TABLE t1 (a INTEGER)
+
+--echo # Connection 2
+connection con2;
+SET DEBUG_SYNC= 'now WAIT_FOR locked';
+SET DEBUG_SYNC= 'before_open_table_wait_refresh SIGNAL called WAIT_FOR created';
+--echo # This call used to cause an assertion. MDL locking conflict will
+--echo # cause back-off and retry. A variable indicating if a prelocking list
+--echo # exists, used to be not reset properly causing an eventual assert.
+--echo # Sending:
+--send CALL p1()
+
+--echo # Connection default
+connection default;
+--echo # Reaping: CREATE TABLE t1 (a INTEGER)
+--error ER_TABLE_EXISTS_ERROR
+--reap
+SET DEBUG_SYNC= 'now SIGNAL created';
+
+--echo # Connection 2
+connection con2;
+--echo # Reaping: CALL p1()
+--reap;
+
+--echo # Connection default
+connection default;
+disconnect con2;
 DROP PROCEDURE p1;
+DROP FUNCTION f1;
+DROP TABLE t1;
+SET DEBUG_SYNC= 'RESET';
 
-SET DEBUG_SYNC = 'RESET';
 
+# Check that all connections opened by test cases in this file are really
+# gone so execution of other tests won't be affected by their presence.
+--source include/wait_until_count_sessions.inc

sql/sql_parse.cc

@@ -31,6 +31,7 @@
 #include "transaction.h"
 #include "sql_audit.h"
 #include "sql_prepare.h"
+#include "debug_sync.h"
 #include "probes_mysql.h"
 #include "set_var.h"
 
@@ -2115,6 +2116,11 @@ mysql_execute_command(THD *thd)
     if (thd->global_read_lock.wait_if_global_read_lock(thd, FALSE, TRUE))
       goto error;
 
+#ifndef DBUG_OFF
+  if (lex->sql_command != SQLCOM_SET_OPTION)
+    DEBUG_SYNC(thd,"before_execute_sql_command");
+#endif
+
   switch (lex->sql_command) {
 
   case SQLCOM_SHOW_EVENTS: