#At file:///home/dlenev/src/bzr/mysql-6.0-3726-w2/
2658 Dmitry Lenev 2008-06-04
WL#3726 "DDL locking for all metadata objects"
After review fixes in progress.
Got rid of TABLE_LIST::mdl_upgradable member and related functions
by using special flag which to be passed to open_table() which
asks it to take upgradable metadata lock on table being opened.
modified:
sql/mysql_priv.h
sql/sql_base.cc
sql/sql_insert.cc
sql/sql_parse.cc
sql/sql_table.cc
sql/sql_view.cc
sql/table.h
per-file comments:
sql/mysql_priv.h
Added one more argument to open_n_lock_single_table() call to be
able to pass flags to open_table() and mysql_lock_tables() called
by it.
Added new flag for controlling open_table() behavior asks it
to take upgradable metadata locks on tables open for write.
sql/sql_base.cc
Added new flag for controlling open_table() behavior asks it
to take upgradable metadata locks on tables open for write.
This allowed us to get rid of TABLE_LIST::mdl_upgradable member.
Added one more argument to open_n_lock_single_table() call to be
able to pass flags to open_table() and mysql_lock_tables() called
by it.
sql/sql_insert.cc
Added one more argument to open_n_lock_single_table() call to be
able to pass flags to open_table() and mysql_lock_tables() called
by it.
sql/sql_parse.cc
Got rid of TABLE_LIST::mdl_upgradable member by using special
flag which to be passed to open_table() which asks it to take upgradable metadata lock on table being opened.
As result also got rid of adjust_mdl_locks_upgradability() function.
sql/sql_table.cc
Got rid of TABLE_LIST::mdl_upgradable member and related functions
by using special flag which to be passed to open_table() which
asks it to take upgradable metadata lock on table being opened.
sql/sql_view.cc
Got rid of TABLE_LIST::mdl_upgradable member and related functions
by using special flag which to be passed to open_table() which
asks it to take upgradable metadata lock on table being opened.
sql/table.h
Got rid of TABLE_LIST::mdl_upgradable member and related functions
by using special flag which to be passed to open_table() which
asks it to take upgradable metadata lock on table being opened.
=== modified file 'sql/mysql_priv.h'
--- a/sql/mysql_priv.h 2008-06-02 14:30:18 +0000
+++ b/sql/mysql_priv.h 2008-06-04 12:27:06 +0000
@@ -1605,7 +1605,7 @@ inline int open_and_lock_tables(THD *thd
}
/* simple open_and_lock_tables without derived handling for single table */
TABLE *open_n_lock_single_table(THD *thd, TABLE_LIST *table_l,
- thr_lock_type lock_type);
+ thr_lock_type lock_type, uint flags);
bool open_normal_and_derived_tables(THD *thd, TABLE_LIST *tables, uint flags);
int lock_tables(THD *thd, TABLE_LIST *tables, uint counter, uint flags,
bool *need_reopen);
@@ -2136,6 +2136,7 @@ MYSQL_LOCK *mysql_lock_tables(THD *thd,
#define MYSQL_OPEN_TEMPORARY_ONLY 0x0004
#define MYSQL_LOCK_IGNORE_GLOBAL_READ_ONLY 0x0008
#define MYSQL_LOCK_PERF_SCHEMA 0x0010
+#define MYSQL_OPEN_TAKE_UPGRADABLE_MDL 0x0020
void mysql_unlock_tables(THD *thd, MYSQL_LOCK *sql_lock);
void mysql_unlock_read_tables(THD *thd, MYSQL_LOCK *sql_lock);
=== modified file 'sql/sql_base.cc'
--- a/sql/sql_base.cc 2008-06-03 17:41:59 +0000
+++ b/sql/sql_base.cc 2008-06-04 12:27:06 +0000
@@ -2537,6 +2537,9 @@ void table_share_release_hook(void *shar
No version number checking is done.
MYSQL_OPEN_TEMPORARY_ONLY - Open only temporary
table not the base table or view.
+ MYSQL_OPEN_TAKE_UPGRADABLE_MDL - Obtain upgradable
+ metadata lock for tables on which we are going to
+ take some kind of write table-level lock.
IMPLEMENTATION
Uses a cache of open tables to find a table not in use.
@@ -2780,7 +2783,8 @@ TABLE *open_table(THD *thd, TABLE_LIST *
{
bool retry;
- if (table_list->mdl_upgradable)
+ if (flags & MYSQL_OPEN_TAKE_UPGRADABLE_MDL &&
+ table_list->lock_type >= TL_WRITE_ALLOW_WRITE)
mdl_set_upgradable(mdl_lock_data);
mdl_set_lock_priority(mdl_lock_data, (flags & MYSQL_LOCK_IGNORE_FLUSH) ?
MDL_HIGH_PRIO : MDL_NORMAL_PRIO);
@@ -4803,6 +4807,8 @@ static bool check_lock_and_start_stmt(TH
@param[in] thd thread handle
@param[in] table_l table to open is first table in this list
@param[in] lock_type lock to use for table
+ @param[in] flags options to be used while opening and locking
+ table (see open_table(), mysql_lock_tables())
@return table
@retval != NULL OK, opened table returned
@@ -4828,7 +4834,7 @@ static bool check_lock_and_start_stmt(TH
*/
TABLE *open_n_lock_single_table(THD *thd, TABLE_LIST *table_l,
- thr_lock_type lock_type)
+ thr_lock_type lock_type, uint flags)
{
TABLE_LIST *save_next_global;
DBUG_ENTER("open_n_lock_single_table");
@@ -4844,7 +4850,7 @@ TABLE *open_n_lock_single_table(THD *thd
table_l->required_type= FRMTYPE_TABLE;
/* Open the table. */
- if (simple_open_n_lock_tables(thd, table_l))
+ if (open_and_lock_tables_derived(thd, table_l, FALSE, flags))
table_l->table= NULL; /* Just to be sure. */
/* Restore list. */
=== modified file 'sql/sql_insert.cc'
--- a/sql/sql_insert.cc 2008-05-29 05:45:02 +0000
+++ b/sql/sql_insert.cc 2008-06-04 12:27:06 +0000
@@ -2250,7 +2250,7 @@ void kill_delayed_threads(void)
bool Delayed_insert::open_and_lock_table()
{
if (!(table= open_n_lock_single_table(&thd, &table_list,
- TL_WRITE_DELAYED)))
+ TL_WRITE_DELAYED, 0)))
{
thd.fatal_error(); // Abort waiting inserts
return TRUE;
=== modified file 'sql/sql_parse.cc'
--- a/sql/sql_parse.cc 2008-06-03 17:07:58 +0000
+++ b/sql/sql_parse.cc 2008-06-04 12:27:06 +0000
@@ -52,7 +52,6 @@ int execute_backup_command(THD*,LEX*);
"FUNCTION" : "PROCEDURE")
static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables);
-static void adjust_mdl_locks_upgradability(TABLE_LIST *tables);
const char *any_db="*any*"; // Special symbol for check_access
@@ -3334,9 +3333,9 @@ end_with_restore_list:
thd->options|= OPTION_TABLE_LOCK;
alloc_mdl_locks(all_tables, &thd->locked_tables_root);
thd->mdl_el_root= &thd->locked_tables_root;
- adjust_mdl_locks_upgradability(all_tables);
- if (!(res= simple_open_n_lock_tables(thd, all_tables)))
+ if (!(res= open_and_lock_tables_derived(thd, all_tables, FALSE,
+ MYSQL_OPEN_TAKE_UPGRADABLE_MDL)))
{
#ifdef HAVE_QUERY_CACHE
if (thd->variables.query_cache_wlock_invalidate)
@@ -7677,21 +7676,6 @@ bool parse_sql(THD *thd,
/* That's it. */
return mysql_parse_status || thd->is_fatal_error;
-}
-
-
-/**
- Auxiliary function which marks metadata locks for all tables
- on which we plan to take write lock as upgradable.
-*/
-
-static void adjust_mdl_locks_upgradability(TABLE_LIST *tables)
-{
- for (TABLE_LIST *tab= tables; tab; tab= tab->next_global)
- {
- if (tab->lock_type >= TL_WRITE_ALLOW_WRITE)
- tab->mdl_upgradable= TRUE;
- }
}
/**
=== modified file 'sql/sql_table.cc'
--- a/sql/sql_table.cc 2008-06-03 17:41:59 +0000
+++ b/sql/sql_table.cc 2008-06-04 12:27:06 +0000
@@ -4158,7 +4158,8 @@ static bool mysql_admin_table(THD* thd,
if (view_operator_func == NULL)
table->required_type=FRMTYPE_TABLE;
- open_and_lock_tables(thd, table);
+ open_and_lock_tables_derived(thd, table, TRUE,
+ MYSQL_OPEN_TAKE_UPGRADABLE_MDL);
thd->no_warnings_for_error= 0;
table->next_global= save_next_global;
table->next_local= save_next_local;
@@ -4521,7 +4522,6 @@ err:
bool mysql_repair_table(THD* thd, TABLE_LIST* tables, HA_CHECK_OPT* check_opt)
{
DBUG_ENTER("mysql_repair_table");
- set_all_mdl_upgradable(tables);
DBUG_RETURN(mysql_admin_table(thd, tables, check_opt,
"repair", TL_WRITE, 1,
test(check_opt->sql_flags & TT_USEFRM),
@@ -4534,7 +4534,6 @@ bool mysql_repair_table(THD* thd, TABLE_
bool mysql_optimize_table(THD* thd, TABLE_LIST* tables, HA_CHECK_OPT* check_opt)
{
DBUG_ENTER("mysql_optimize_table");
- set_all_mdl_upgradable(tables);
DBUG_RETURN(mysql_admin_table(thd, tables, check_opt,
"optimize", TL_WRITE, 1,0,0,0,
&handler::ha_optimize, 0));
@@ -6403,9 +6402,8 @@ view_err:
DBUG_RETURN(error);
}
- table_list->mdl_upgradable= TRUE;
-
- if (!(table= open_n_lock_single_table(thd, table_list, TL_WRITE_ALLOW_READ)))
+ if (!(table= open_n_lock_single_table(thd, table_list, TL_WRITE_ALLOW_READ,
+ MYSQL_OPEN_TAKE_UPGRADABLE_MDL)))
DBUG_RETURN(TRUE);
table->use_all_columns();
mdl_lock_data= table->mdl_lock_data;
@@ -7426,7 +7424,7 @@ bool mysql_checksum_table(THD *thd, TABL
strxmov(table_name, table->db ,".", table->table_name, NullS);
- t= table->table= open_n_lock_single_table(thd, table, TL_READ);
+ t= table->table= open_n_lock_single_table(thd, table, TL_READ, 0);
thd->clear_error(); // these errors shouldn't get client
protocol->prepare_for_resend();
=== modified file 'sql/sql_view.cc'
--- a/sql/sql_view.cc 2008-05-29 05:45:02 +0000
+++ b/sql/sql_view.cc 2008-06-04 12:27:06 +0000
@@ -1319,10 +1319,7 @@ bool mysql_make_view(THD *thd, File_pars
anyway.
*/
for (tbl= view_main_select_tables; tbl; tbl= tbl->next_local)
- {
tbl->lock_type= table->lock_type;
- tbl->mdl_upgradable= table->mdl_upgradable;
- }
/*
If the view is mergeable, we might want to
INSERT/UPDATE/DELETE into tables of this view. Preserve the
=== modified file 'sql/table.h'
--- a/sql/table.h 2008-06-02 14:30:18 +0000
+++ b/sql/table.h 2008-06-04 12:27:06 +0000
@@ -1276,11 +1276,6 @@ struct TABLE_LIST
*/
TAKE_EXCLUSIVE_MDL
} open_type;
- /**
- Indicates that for this table/view we need to take shared metadata
- lock which should be upgradable to exclusive metadata lock.
- */
- bool mdl_upgradable;
/* For transactional locking. */
int lock_timeout; /* NOWAIT or WAIT [X] */
bool lock_transactional; /* If transactional lock requested. */
@@ -1664,13 +1659,3 @@ size_t max_row_length(TABLE *table, cons
void alloc_mdl_locks(TABLE_LIST *table_list, MEM_ROOT *root);
-/**
- Helper function which allows to mark all elements in table list
- as requiring upgradable metadata locks.
-*/
-
-inline void set_all_mdl_upgradable(TABLE_LIST *tables)
-{
- for (; tables; tables= tables->next_global)
- tables->mdl_upgradable= TRUE;
-}
