mariadb

Commit Graph

Author	SHA1	Message	Date
Konstantin Osipov	a9013f8fba	Backport of: ---------------------------------------------------------- revno: 2617.23.20 committer: Konstantin Osipov <kostja@sun.com> branch nick: mysql-6.0-runtime timestamp: Wed 2009-03-04 16:31:31 +0300 message: WL#4284 "Transactional DDL locking" Review comments: "Objectify" the MDL API. MDL_request and MDL_context still need manual construction and destruction, since they are used in environment that is averse to constructors/destructors. sql/mdl.cc: Improve comments. Add asserts to backup()/restore_from_backup()/merge() methods. Fix an order bug in the error path of mdl_acquire_exclusive_locks(): we used to first free a ticket object, and only then exclude it from the list of tickets.	16 years ago
Konstantin Osipov	97abce0e7c	Backport of: ---------------------------------------------------------- revno: 2617.23.19 committer: Konstantin Osipov <kostja@sun.com> branch nick: mysql-6.0-runtime timestamp: Tue 2009-03-03 01:20:44 +0300 message: Metadata locking: realign comments. No semantical changes, only enforce a bit of the coding style. This is a review fix for WL#4284 "Transactional DDL locking". sql/mdl.cc: Realign doxygen comments. sql/mdl.h: Realign doxygen comments.	16 years ago
Konstantin Osipov	f477e66ec5	Backport of: ------------------------------------------------------------ revno: 2617.23.18 committer: Davi Arnaut <Davi.Arnaut@Sun.COM> branch nick: 4284-6.0 timestamp: Mon 2009-03-02 18:18:26 -0300 message: Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order WL#4284: Transactional DDL locking This is a prerequisite patch: These changes are intended to split lock requests from granted locks and to allow the memory and lifetime of granted locks to be managed within the MDL subsystem. Furthermore, tickets can now be shared and therefore are used to satisfy multiple lock requests, but only shared locks can be recursive. The problem is that the MDL subsystem morphs lock requests into granted locks locks but does not manage the memory and lifetime of lock requests, and hence, does not manage the memory of granted locks either. This can be problematic because it puts the burden of tracking references on the users of the subsystem and it can't be easily done in transactional contexts where the locks have to be kept around for the duration of a transaction. Another issue is that recursive locks (when the context trying to acquire a lock already holds a lock on the same object) requires that each time the lock is granted, a unique lock request/granted lock structure structure must be kept around until the lock is released. This can lead to memory leaks in transactional contexts as locks taken during the transaction should only be released at the end of the transaction. This also leads to unnecessary wake ups (broadcasts) in the MDL subsystem if the context still holds a equivalent of the lock being released. These issues are exacerbated due to the fact that WL#4284 low-level design says that the implementation should "2) Store metadata locks in transaction memory root, rather than statement memory root" but this is not possible because a memory root, as implemented in mysys, requires all objects allocated from it to be freed all at once. This patch combines review input and significant code contributions from Konstantin Osipov (kostja) and Dmitri Lenev (dlenev). mysql-test/r/mdl_sync.result: Add test case result. mysql-test/t/mdl_sync.test: Add test case for shared lock upgrade case. sql/event_db_repository.cc: Rename mdl_alloc_lock to mdl_request_alloc. sql/ha_ndbcluster_binlog.cc: Use new function names to initialize MDL lock requests. sql/lock.cc: Rename MDL functions. sql/log_event.cc: The MDL request now holds the table and database name data (MDL_KEY). sql/mdl.cc: Move the MDL key to the MDL_LOCK structure in order to make the object suitable for allocation from a fixed-size allocator. This allows the simplification of the lists in the MDL_LOCK object, which now are just two, one for granted tickets and other for waiting (upgraders) tickets. Recursive requests for a shared lock on the same object can now be granted using the same lock ticket. This schema is only used for shared locks because that the only case that matters. This is used to avoid waste of resources in case a context (connection) already holds a shared lock on a object. sql/mdl.h: Introduce a metadata lock object key which is used to uniquely identify lock objects. Separate the structure used to represent pending lock requests from the structure used to represent granted metadata locks. Rename functions used to manipulate locks requests in order to have a more consistent function naming schema. sql/sp_head.cc: Rename mdl_alloc_lock to mdl_request_alloc. sql/sql_acl.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_base.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_class.h: Last acquired lock before the savepoint was set. sql/sql_delete.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_handler.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_insert.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_parse.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_plist.h: Typedef for iterator type. sql/sql_plugin.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_servers.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_show.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_table.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_trigger.cc: Save reference to the lock ticket so it can be downgraded later. sql/sql_udf.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/table.cc: Rename mdl_alloc_lock to mdl_request_alloc. sql/table.h: Separate MDL lock requests from lock tickets (granted locks). storage/myisammrg/ha_myisammrg.cc: Rename alloc_mdl_locks to alloc_mdl_requests.	16 years ago
Konstantin Osipov	124cda8a0a	Backport of: ------------------------------------------------------------ revno: 2630.4.33 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Fri 2008-06-20 17:11:20 +0400 message: WL#3726 "DDL locking for all metadata objects". After-review fixes in progress. Minimized dependency of mdl.cc on other modules (particularly made it independant of mysql_priv.h) in order to be able write unit tests for metadata locking subsystem. sql/ha_ndbcluster_binlog.cc: Use newly introduced MAX_MDLKEY_LENGTH constant for allocating buffer for object key for metadata locking subsystem. sql/log_event.cc: Use newly introduced MAX_MDLKEY_LENGTH constant for allocating buffer for object key for metadata locking subsystem. sql/mdl.cc: Removed dependency on THD class (and thus on mysql_priv.h) by using direct access to members of st_my_thread_var instead of accessing THD::killed/enter_cond()/exit_cond(). sql/mdl.h: Added MAX_MDLKEY_LENGTH constant to be used for allocating buffers for key for metadata locking subsystem. Added declarations of server kernel functions used by metadata locking subsystem to mdl.h in order to decrease dependency of mdl.cc on other files. sql/mysql_priv.h: Moved declaration of notify_thread_having_shared_lock() to the mdl.h (also renamed it to make clear in metadata locking code that it is a callback to SQL-layer). sql/sql_base.cc: Renamed notify_thread_having_shared_lock() to make it clear in metadata locking subsystem code that it is a callback to SQL layer. sql/sql_handler.cc: Use newly introduced MAX_MDLKEY_LENGTH constant for allocating buffer for object key for metadata locking subsystem. sql/sql_show.cc: Use newly introduced MAX_MDLKEY_LENGTH constant for allocating buffer for object key for metadata locking subsystem.	16 years ago
Konstantin Osipov	e3b3907c4f	Backport of: ------------------------------------------------------------ revno: 2630.4.32 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Thu 2008-06-19 16:39:58 +0400 message: WL#3726 "DDL locking for all metadata objects". After-review fixes in progress. Ensure that metadata locking subsystem properly handles out-of-memory conditions. Clarified MDL interface by separating release of locks and removal of lock requests from the context. sql/lock.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. sql/mdl.cc: Ensured that metadata locking subsystem properly handles out-of-memory conditions. Introduced new MDL_INITIALIZED state for metadata lock request which is used in all cases when lock is not acquired and we have not associated request with object respesenting lock. MDL_PENDING is now only used for requests for exclusive locks which are added to the MDL_LOCK::waiting_exclusive queue. mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and newly introduced mdl_remove_lock() to do this. Also renamed mdl_release_all_locks_for_name() to emphasize that it also actually removes lock requests from the context. Finally mdl_try_acquire_exclusive_lock() is now returs information about encountered lock conflict in separate out parameter since its return value is used for distinguishing between error (e.g. due to OOM) and success. sql/mdl.h: Introduced new MDL_INITIALIZED state for metadata lock request which is used in all cases when lock is not acquired and we have not associated request with object respesenting lock. MDL_PENDING is now only used for requests for exclusive locks which are added to the MDL_LOCK::waiting_exclusive queue. mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and newly introduced mdl_remove_lock() to do this. Also renamed mdl_release_all_locks_for_name() to emphasize that it also actually removes lock requests from the context. Finally mdl_try_acquire_exclusive_lock() is now returs information about encountered lock conflict in separate out parameter since its return value is used for distinguishing between error (e.g. due to OOM) and success. sql/sql_base.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. Also adjusted open_table() to ensure that it releases/removes metadata locks in case of error after adding/acquiring them (unless keeping these lock requests is required for recovering action). sql/sql_delete.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. sql/sql_handler.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. sql/sql_show.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. sql/sql_table.cc: Renamed mdl_release_all_locks_for_name() to emphasize that it also actually removes lock requests from the context. mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. Finally mdl_try_acquire_exclusive_lock() is now returs information about encountered lock conflict in separate out parameter since its return value is used for distinguishing between error (e.g. due to OOM) and success.	16 years ago
Konstantin Osipov	f7ba9dafd5	Backport of: ------------------------------------------------------------ revno: 2630.9.2 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w3 timestamp: Tue 2008-06-10 18:01:56 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. sql/mdl.cc: Changed mdl_acquire_shared_lock() signature to accept MDL_CONTEXT as one of arguments as described in specification. sql/mdl.h: Changed mdl_acquire_shared_lock() signature to accept MDL_CONTEXT as one of arguments as described in specification. sql/sql_base.cc: Changed mdl_acquire_shared_lock() signature to accept MDL_CONTEXT as one of arguments as described in specification. Renamed handle_failed_open_table_attempt() to recover_from_failed_open_table_attempt() as suggested by review. Added comment clarifying why we need to check TABLE::db_stat while looking at TABLE instances open by other threads. sql/sql_show.cc: Changed mdl_acquire_shared_lock() signature to accept MDL_CONTEXT as one of arguments as described in specification.	16 years ago
Konstantin Osipov	d0a1f640db	Backport of: ------------------------------------------------------------ revno: 2630.4.24 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Fri 2008-06-06 14:28:58 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. Get rid of upgradability and priority attributes of metadata lock requests by replacing them with two new types of lock requests MDL_SHARED_UPGRADABLE and MDL_SHARED_HIGH_PRIO correspondingly.	16 years ago
Konstantin Osipov	b05303c132	Backport of: ------------------------------------------------------------ revno: 2630.4.18 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Tue 2008-06-03 21:07:58 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. Now during upgrading/downgrading metadata locks we deal with individual metadata lock requests rather than with all requests for this object in the context. This makes API a bit more clear and makes adjust_mdl_locks_upgradability() much nicer. sql/lock.cc: lock_table_names(): Set TABLE_LIST::mdl_lock_data when allocating new metadata lock request object for table list element. sql/mdl.cc: Now during upgrading/downgrading metadata locks we deal with individual metadata lock requests rather than with all requests for this object in the context. Adjusted upgrade/ downgrade functions accordingly. We also got rid of mdl_release_exclusive_locks() and now release locks individually. To simplify this process mdl_release_all_locks_for_name() was introduced. sql/mdl.h: Now during upgrading/downgrading metadata locks we deal with individual metadata lock requests rather than with all requests for this object in the context. Adjusted upgrade/ downgrade functions accordingly. We also got rid of mdl_release_exclusive_locks() and now release locks individually. To simplify this process mdl_release_all_locks_for_name() was introduced. sql/sql_base.cc: Now during upgrading/downgrading metadata locks we deal with individual metadata lock requests rather than with all requests for this object in the context. We also got rid of mdl_release_exclusive_locks() and now release locks individually. sql/sql_parse.cc: adjust_mdl_locks_upgradability() is much simplier now due to the fact that now during upgrading/downgrading metadata locks we deal with individual metadata lock requests rather than with all requests for this object in the context. sql/sql_table.cc: Now during upgrading/downgrading metadata locks we deal with individual metadata lock requests rather than with all requests for this object in the context. Adjusted upgrade/ downgrade functions accordingly. We also got rid of mdl_release_exclusive_locks() and now release locks individually. To simplify this process mdl_release_all_locks_for_name() was introduced. sql/sql_trigger.cc: ow during upgrading/downgrading metadata locks we deal with individual metadata lock requests rather than with all requests for this object in the context.	16 years ago
Konstantin Osipov	e23046d1bc	Backport of: ------------------------------------------------------------ revno: 2630.4.17 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Thu 2008-05-29 16:52:56 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. "The great correction of names". Renamed MDL_LOCK and MDL_LOCK_DATA classes to make usage of these names in metadata locking subsystem consistent with other parts of server (i.e. thr_lock.cc). Now we MDL_LOCK_DATA corresponds to request for a lock and MDL_LOCK to the lock itself. Adjusted code in MDL subsystem and other places using these classes accordingly. Did similar thing for GLOBAL_MDL_LOCK_DATA class and also changed name of its members to correspond to names of MDL_LOCK_DATA members. Finally got rid of usage of one letter variables in MDL code since it makes code harder to search in (according to reviewer).	16 years ago
Konstantin Osipov	de1979d3d6	Backport of: ------------------------------------------------------------ revno: 2630.4.10 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w timestamp: Mon 2008-05-26 15:11:26 +0400 message: WL#3726 "DDL locking for all metadata objects". After review changes in progress. Implemented some renames suggested by reviewer. sql/mdl.cc: Renamed: MDL_LOCK_DATA::users -> lock_count MDL_LOCK_DATA::has_no_other_users() -> has_one_lock() MDL_LOCK::upgradable -> is_upgradable Moved variables used in global metadata lock implementation to separate strucuture. sql/mdl.h: Renamed MDL_LOCK::upgradable to is_upgradable.	16 years ago
Konstantin Osipov	eff3780dd8	Initial import of WL#3726 "DDL locking for all metadata objects". Backport of: ------------------------------------------------------------ revno: 2630.4.1 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w timestamp: Fri 2008-05-23 17:54:03 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. ------------------------------------------------------------ This is the first patch in series. It transforms the metadata locking subsystem to use a dedicated module (mdl.h,cc). No significant changes in the locking protocol. The import passes the test suite with the exception of deprecated/removed 6.0 features, and MERGE tables. The latter are subject to a fix by WL#4144. Unfortunately, the original changeset comments got lost in a merge, thus this import has its own (largely insufficient) comments. This patch fixes Bug#25144 "replication / binlog with view breaks". Warning: this patch introduces an incompatible change: Under LOCK TABLES, it's no longer possible to FLUSH a table that was not locked for WRITE. Under LOCK TABLES, it's no longer possible to DROP a table or VIEW that was not locked for WRITE. **** Backport of: ------------------------------------------------------------ revno: 2630.4.2 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w timestamp: Sat 2008-05-24 14:03:45 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. ** Backport of: ------------------------------------------------------------ revno: 2630.4.3 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w timestamp: Sat 2008-05-24 14:08:51 +0400 message: WL#3726 "DDL locking for all metadata objects" Fixed failing Windows builds by adding mdl.cc to the lists of files needed to build server/libmysqld on Windows. ** Backport of: ------------------------------------------------------------ revno: 2630.4.4 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w timestamp: Sat 2008-05-24 21:57:58 +0400 message: WL#3726 "DDL locking for all metadata objects". Fix for assert failures in kill.test which occured when one tried to kill ALTER TABLE statement on merge table while it was waiting in wait_while_table_is_used() for other connections to close this table. These assert failures stemmed from the fact that cleanup code in this case assumed that temporary table representing new version of table was open with adding to THD::temporary_tables list while code which were opening this temporary table wasn't always fulfilling this. This patch changes code that opens new version of table to always do this linking in. It also streamlines cleanup process for cases when error occurs while we have new version of table open. ** WL#3726 "DDL locking for all metadata objects" Add libmysqld/mdl.cc to .bzrignore. ** Backport of: ------------------------------------------------------------ revno: 2630.4.6 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w timestamp: Sun 2008-05-25 00:33:22 +0400 message: WL#3726 "DDL locking for all metadata objects". Addition to the fix of assert failures in kill.test caused by changes for this worklog. Make sure we close the new table only once. .bzrignore: Add libmysqld/mdl.cc libmysqld/CMakeLists.txt: Added mdl.cc to the list of files needed for building of libmysqld. libmysqld/Makefile.am: Added files implementing new meta-data locking subsystem to the server. mysql-test/include/handler.inc: Use separate connection for waiting while threads performing DDL operations conflicting with open HANDLER tables reach blocked state. This is required because now we check and close tables open by HANDLER statements in this connection conflicting with DDL in another each time open_tables() is called and thus select from I_S which is used for waiting will unblock DDL operations if issued from connection with open HANDLERs. mysql-test/r/create.result: Adjusted test case after change in implementation of CREATE TABLE ... SELECT. We no longer have special check in open_table() which catches the case when we select from the table created. Instead we rely on unique_table() call which happens after opening and locking all tables. mysql-test/r/flush.result: FLUSH TABLES WITH READ LOCK can no longer happen under LOCK TABLES. Updated test accordingly. mysql-test/r/flush_table.result: Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables locked for read. Updated test accordingly. mysql-test/r/handler_innodb.result: Use separate connection for waiting while threads performing DDL operations conflicting with open HANDLER tables reach blocked state. This is required because now we check and close tables open by HANDLER statements in this connection conflicting with DDL in another each time open_tables() is called and thus select from I_S which is used for waiting will unblock DDL operations if issued from connection with open HANDLERs. mysql-test/r/handler_myisam.result: Use separate connection for waiting while threads performing DDL operations conflicting with open HANDLER tables reach blocked state. This is required because now we check and close tables open by HANDLER statements in this connection conflicting with DDL in another each time open_tables() is called and thus select from I_S which is used for waiting will unblock DDL operations if issued from connection with open HANDLERs. mysql-test/r/information_schema.result: Additional test for WL#3726 "DDL locking for all metadata objects". Check that we use high-priority metadata lock requests when filling I_S tables. Rearrange tests to match 6.0 better (fewer merge conflicts). mysql-test/r/kill.result: Added tests checking that DDL and DML statements waiting for metadata locks can be interrupted by KILL command. mysql-test/r/lock.result: One no longer is allowed to do DROP VIEW under LOCK TABLES even if this view is locked by LOCK TABLES. The problem is that in such situation write locks on view are not mutually exclusive so upgrading metadata lock which is required for dropping of view will lead to deadlock. mysql-test/r/partition_column_prune.result: Update results (same results in 6.0), WL#3726 mysql-test/r/partition_pruning.result: Update results (same results in 6.0), WL#3726 mysql-test/r/ps_ddl.result: We no longer invalidate prepared CREATE TABLE ... SELECT statement if target table changes. This is OK since it is not strictly necessary. The first change is wrong, is caused by FLUSH TABLE now flushing all unused tables. This is a regression that Dmitri fixed in 6.0 in a follow up patch. mysql-test/r/sp.result: Under LOCK TABLES we no longer allow accessing views which were not explicitly locked. To access view we need to obtain metadata lock on it and doing this under LOCK TABLES may lead to deadlocks. mysql-test/r/view.result: One no longer is allowed to do DROP VIEW under LOCK TABLES even if this view is locked by LOCK TABLES. The problem is that in such situation even "write locks" on view are not mutually exclusive so upgrading metadata lock which is required for dropping of view will lead to deadlock mysql-test/r/view_grant.result: ALTER VIEW implementation was changed to open a view only after checking that user which does alter has appropriate privileges on it. This means that in case when user's privileges are insufficient for this we won't check that new view definer is the same as original one or user performing alter has SUPER privilege. Adjusted test case accordingly. mysql-test/r/view_multi.result: Added test case for bug#25144 "replication / binlog with view breaks". mysql-test/suite/rpl/t/disabled.def: Disable test for deprecated features (they don't work with new MDL). mysql-test/t/create.test: Adjusted test case after change in implementation of CREATE TABLE ... SELECT. We no longer have special check in open_table() which catches the case when we select from the table created. Instead we rely on unique_table() call which happens after opening and locking all tables. mysql-test/t/disabled.def: Disable merge.test, subject of WL#4144 mysql-test/t/flush.test: FLUSH TABLES WITH READ LOCK can no longer happen under LOCK TABLES. Updated test accordingly. mysql-test/t/flush_table.test: Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables locked for read. Updated test accordingly. mysql-test/t/information_schema.test: Additional test for WL#3726 "DDL locking for all metadata objects". Check that we use high-priority metadata lock requests when filling I_S tables. Rearrange the results for easier merges with 6.0. mysql-test/t/kill.test: Added tests checking that DDL and DML statements waiting for metadata locks can be interrupted by KILL command. mysql-test/t/lock.test: One no longer is allowed to do DROP VIEW under LOCK TABLES even if this view is locked by LOCK TABLES. The problem is that in such situation write locks on view are not mutually exclusive so upgrading metadata lock which is required for dropping of view will lead to deadlock. mysql-test/t/lock_multi.test: Adjusted test case to the changes of status in various places caused by change in implementation FLUSH TABLES WITH READ LOCK, which is now takes global metadata lock before flushing tables and therefore waits on at these places. mysql-test/t/ps_ddl.test: We no longer invalidate prepared CREATE TABLE ... SELECT statement if target table changes. This is OK since it is not strictly necessary. The first change is wrong, is caused by FLUSH TABLE now flushing all unused tables. This is a regression that Dmitri fixed in 6.0 in a follow up patch. mysql-test/t/sp.test: Under LOCK TABLES we no longer allow accessing views which were not explicitly locked. To access view we need to obtain metadata lock on it and doing this under LOCK TABLES may lead to deadlocks. mysql-test/t/trigger_notembedded.test: Adjusted test case to the changes of status in various places caused by change in implementation FLUSH TABLES WITH READ LOCK, which is now takes global metadata lock before flushing tables and therefore waits on at these places. mysql-test/t/view.test: One no longer is allowed to do DROP VIEW under LOCK TABLES even if this view is locked by LOCK TABLES. The problem is that in such situation even "write locks" on view are not mutually exclusive so upgrading metadata lock which is required for dropping of view will lead to deadlock. mysql-test/t/view_grant.test: ALTER VIEW implementation was changed to open a view only after checking that user which does alter has appropriate privileges on it. This means that in case when user's privileges are insufficient for this we won't check that new view definer is the same as original one or user performing alter has SUPER privilege. Adjusted test case accordingly. mysql-test/t/view_multi.test: Added test case for bug#25144 "replication / binlog with view breaks". sql/CMakeLists.txt: Added mdl.cc to the list of files needed for building of server. sql/Makefile.am: Added files implementing new meta-data locking subsystem to the server. sql/event_db_repository.cc: Allocate metadata lock requests objects (MDL_LOCK) on execution memory root in cases when TABLE_LIST objects is also allocated there or on stack. sql/ha_ndbcluster.cc: Adjusted code to work nicely with new metadata locking subsystem. close_cached_tables() no longer has wait_for_placeholder argument. Instead of relying on this parameter and related behavior FLUSH TABLES WITH READ LOCK now takes global shared metadata lock. sql/ha_ndbcluster_binlog.cc: Adjusted code to work with new metadata locking subsystem. close_cached_tables() no longer has wait_for_placeholder argument. Instead of relying on this parameter and related behavior FLUSH TABLES WITH READ LOCK now takes global shared metadata lock. sql/handler.cc: update_frm_version(): Directly update TABLE_SHARE::mysql_version member instead of going through all TABLE instances for this table (old code was a legacy from pre-table-definition-cache days). sql/lock.cc: Use new metadata locking subsystem. Threw away most of functions related to name locking as now one is supposed to use metadata locking API instead. In lock_global_read_lock() and unlock_global_read_lock() in order to avoid problems with global read lock sneaking in at the moment when we perform FLUSH TABLES or ALTER TABLE under LOCK TABLES and when tables being reopened are protected only by metadata locks we also have to take global shared meta data lock. sql/log_event.cc: Adjusted code to work with new metadata locking subsystem. For tables open by slave thread for applying RBR events allocate memory for lock request object in the same chunk of memory as TABLE_LIST objects for them. In order to ensure that we keep these objects around until tables are open always close tables before calling Relay_log_info::clear_tables_to_lock(). Use new auxiliary Relay_log_info::slave_close_thread_tables() method to enforce this. sql/log_event_old.cc: Adjusted code to work with new metadata locking subsystem. Since for tables open by slave thread for applying RBR events memory for lock request object is allocated in the same chunk of memory as TABLE_LIST objects for them we have to ensure that we keep these objects around until tables are open. To ensure this we always close tables before calling Relay_log_info::clear_tables_to_lock(). To enfore this we use new auxiliary Relay_log_info::slave_close_thread_tables() method. sql/mdl.cc: Implemented new metadata locking subsystem and API described in WL3726 "DDL locking for all metadata objects". sql/mdl.h: Implemented new metadata locking subsystem and API described in WL3726 "DDL locking for all metadata objects". sql/mysql_priv.h: - close_thread_tables()/close_tables_for_reopen() now has one more argument which indicates that metadata locks should be released but not removed from the context in order to be used later in mdl_wait_for_locks() and tdc_wait_for_old_version(). - close_cached_table() routine is no longer public. - Thread waiting in wait_while_table_is_used() can be now killed so this function returns boolean to make caller aware of such situation. - We no longer have table cache as separate entity instead used and unused TABLE instances are linked to TABLE_SHARE objects in table definition cache. - Now third argument of open_table() is also used for requesting table repair or auto-discovery of table's new definition. So its type was changed from bool to enum. - Added tdc_open_view() function for opening view by getting its definition from disk (and table cache in future). - reopen_name_locked_table() no longer needs "link_in" argument as now we have exclusive metadata locks instead of dummy TABLE instances when this function is called. - find_locked_table() now takes head of list of TABLE instances instead of always scanning through THD::open_tables list. Also added find_write_locked_table() auxiliary. - reopen_tables(), close_cached_tables() no longer have mark_share_as_old and wait_for_placeholder arguments. Instead of relying on this parameters and related behavior FLUSH TABLES WITH READ LOCK now takes global shared metadata lock. - We no longer need drop_locked_tables() and abort_locked_tables(). - mysql_ha_rm_tables() now always assume that LOCK_open is not acquired by caller. - Added notify_thread_having_shared_lock() callback invoked by metadata locking subsystem when acquiring an exclusive lock, for each thread that has a conflicting shared metadata lock. - Introduced expel_table_from_cache() as replacement for remove_table_from_cache() (the main difference is that this new function assumes that caller follows metadata locking protocol and never waits). - Threw away most of functions related to name locking. One should use new metadata locking subsystem and API instead. sql/mysqld.cc: Got rid of call initializing/deinitializing table cache since now it is embedded into table definition cache. Added calls for initializing/ deinitializing metadata locking subsystem. sql/rpl_rli.cc: Introduced auxiliary Relay_log_info::slave_close_thread_tables() method which is used for enforcing that we always close tables open for RBR before deallocating TABLE_LIST elements and MDL_LOCK objects for them. sql/rpl_rli.h: Introduced auxiliary Relay_log_info::slave_close_thread_tables() method which is used for enforcing that we always close tables open for RBR before deallocating TABLE_LIST elements and MDL_LOCK objects for them. sql/set_var.cc: close_cached_tables() no longer has wait_for_placeholder argument. Instead of relying on this parameter and related behavior FLUSH TABLES WITH READ LOCK now takes global shared metadata lock. sql/sp_head.cc: For tables added to the statement's table list by prelocking algorithm we allocate these objects either on the same memory as corresponding table list elements or on THD::locked_tables_root (if we are building table list for LOCK TABLES). sql/sql_acl.cc: Allocate metadata lock requests objects (MDL_LOCK) on execution memory root in cases when we use stack TABLE_LIST objects to open tables. Got rid of redundant code by using unlock_locked_tables() function. sql/sql_base.cc: Changed code to use new MDL subsystem. Got rid of separate table cache. Now used and unused TABLE instances are linked to the TABLE_SHAREs in table definition cache. check_unused(): Adjusted code to the fact that we no longer have separate table cache. Removed dead code. table_def_free(): Free TABLE instances referenced from TABLE_SHARE objects before destroying table definition cache. get_table_share(): Added assert which ensures that noone will be able to access table (and its share) without acquiring some kind of metadata lock first. close_handle_and_leave_table_as_lock(): Adjusted code to the fact that TABLE instances now are linked to list in TABLE_SHARE. list_open_tables(): Changed this function to use table definition cache instead of table cache. free_cache_entry(): Unlink freed TABLE elements from the list of all TABLE instances for the table in TABLE_SHARE. kill_delayed_thread_for_table(): Added auxiliary for killing delayed insert threads for particular table. close_cached_tables(): Got rid of wait_for_refresh argument as we now rely on global shared metadata lock to prevent FLUSH WITH READ LOCK sneaking in when we are reopening tables. Heavily reworked this function to use new MDL code and not to rely on separate table cache entity. close_open_tables(): We no longer have separate table cache. close_thread_tables(): Release metadata locks after closing all tables. Added skip_mdl argument which allows us not to remove metadata lock requests from the context in case when we are going to use this requests later in mdl_wait_for_locks() and tdc_wait_for_old_versions(). close_thread_table()/close_table_for_reopen(): Since we no longer have separate table cache and all TABLE instances are linked to TABLE_SHARE objects in table definition cache we have to link/unlink TABLE object to/from appropriate lists in the share. name_lock_locked_table(): Moved redundant code to find_write_locked_table() function and adjusted code to the fact that wait_while_table_is_used() can now return with an error if our thread is killed. reopen_table_entry(): We no longer need "link_in" argument as with MDL we no longer call this function with dummy TABLE object pre-allocated and added to the THD::open_tables. Also now we add newly-open TABLE instance to the list of share's used TABLE instances. table_cache_insert_placeholder(): Got rid of name-locking legacy. lock_table_name_if_not_cached(): Moved to sql_table.cc the only place where it is used. It was also reimplemented using new MDL API. open_table(): - Reworked this function to use new MDL subsystem. - Changed code to deal with table definition cache directly instead of going through separate table cache. - Now third argument is also used for requesting table repair or auto-discovery of table's new definition. So its type was changed from bool to enum. find_locked_table()/find_write_locked_table(): Accept head of list of TABLE objects as first argument and use this list instead of always searching in THD::open_tables list. Also added auxiliary for finding write-locked locked tables. reopen_table(): Adjusted function to work with new MDL subsystem and to properly manuipulate with lists of used/unused TABLE instaces in TABLE_SHARE. reopen_tables(): Removed mark_share_as_old parameter. Instead of relying on it and related behavior FLUSH TABLES WITH READ LOCK now takes global shared metadata lock. Changed code after removing separate table cache. drop_locked_tables()/abort_locked_tables(): Got rid of functions which are no longer needed. unlock_locked_tables(): Moved this function from sql_parse.cc and changed it to release memory which was used for allocating metadata lock requests for tables open and locked by LOCK TABLES. tdc_open_view(): Intoduced function for opening a view by getting its definition from disk (and table cache in future). reopen_table_entry(): Introduced function for opening table definitions while holding exclusive metatadata lock on it. open_unireg_entry(): Got rid of this function. Most of its functionality is relocated to open_table() and open_table_fini() functions, and some of it to reopen_table_entry() and tdc_open_view(). Also code resposible for auto-repair and auto-discovery of tables was moved to separate function. open_table_entry_fini(): Introduced function which contains common actions which finalize process of TABLE object creation. auto_repair_table(): Moved code responsible for auto-repair of table being opened here. handle_failed_open_table_attempt() Moved code responsible for handling failing attempt to open table to one place (retry due to lock conflict/old version, auto-discovery and repair). open_tables(): - Flush open HANDLER tables if they have old version of if there is conflicting metadata lock against them (before this moment we had this code in open_table()). - When we open view which should be processed via derived table on the second execution of prepared statement or stored routine we still should call open_table() for it in order to obtain metadata lock on it and prepare its security context. - In cases when we discover that some special handling of failure to open table is needed call handle_failed_open_table_attempt() which handles all such scenarios. open_ltable(): Handling of various special scenarios of failure to open a table was moved to separate handle_failed_open_table_attempt() function. remove_db_from_cache(): Removed this function as it is no longer used. notify_thread_having_shared_lock(): Added callback which is invoked by MDL subsystem when acquiring an exclusive lock, for each thread that has a conflicting shared metadata lock. expel_table_from_cache(): Introduced function for removing unused TABLE instances. Unlike remove_table_from_cache() it relies on caller following MDL protocol and having appropriate locks when calling it and thus does not do any waiting if table is still in use. tdc_wait_for_old_version(): Added function which allows open_tables() to wait in cases when we discover that we should back-off due to presence of old version of table. abort_and_upgrade_lock(): Use new MDL calls. mysql_wait_completed_table(): Got rid of unused function. open_system_tables_for_read/for_update()/performance_schema_table(): Allocate MDL_LOCK objects on execution memory root in cases when TABLE_LIST objects for corresponding tables is allocated on stack. close_performance_schema_table(): Release metadata locks after closing tables. **** Use I_P_List for free/used tables list in the table share. sql/sql_binlog.cc: Use Relay_log_info::slave_close_thread_tables() method to enforce that we always close tables open for RBR before deallocating TABLE_LIST elements and MDL_LOCK objects for them. sql/sql_class.cc: Added meta-data locking contexts as part of Open_tables_state context. Also introduced THD::locked_tables_root memory root which is to be used for allocating MDL_LOCK objects for tables in LOCK TABLES statement (end of lifetime for such objects is UNLOCK TABLES so we can't use statement or execution root for them). sql/sql_class.h: Added meta-data locking contexts as part of Open_tables_state context. Also introduced THD::locked_tables_root memory root which is to be used for allocating MDL_LOCK objects for tables in LOCK TABLES statement (end of lifetime for such objects is UNLOCK TABLES so we can't use statement or execution root for them). Note: handler_mdl_context and locked_tables_root and mdl_el_root will be removed by subsequent patches. sql/sql_db.cc: mysql_rm_db() does not really need to call remove_db_from_cache() as it drops each table in the database using mysql_rm_table_part2(), which performs all necessary operations on table (definition) cache. sql/sql_delete.cc: Use the new metadata locking API for TRUNCATE. sql/sql_handler.cc: Changed HANDLER implementation to use new metadata locking subsystem. Note that MDL_LOCK objects for HANDLER tables are allocated in the same chunk of heap memory as TABLE_LIST object for those tables. sql/sql_insert.cc: mysql_insert(): find_locked_table() now takes head of list of TABLE object as its argument instead of always scanning through THD::open_tables list. handle_delayed_insert(): Allocate metadata lock request object for table open by delayed insert thread on execution memroot. create_table_from_items(): We no longer allocate dummy TABLE objects for tables being created if they don't exist. As consequence reopen_name_locked_table() no longer has link_in argument. open_table() now has one more argument which is not relevant for temporary tables. sql/sql_parse.cc: - Moved unlock_locked_tables() routine to sql_base.cc and made available it in other files. Got rid of some redundant code by using this function. - Replaced boolean TABLE_LIST::create member with enum open_table_type member. - Use special memory root for allocating MDL_LOCK objects for tables open and locked by LOCK TABLES (these object should live till UNLOCK TABLES so we can't allocate them on statement nor execution memory root). Also properly set metadata lock upgradability attribure for those tables. - Under LOCK TABLES it is no longer allowed to flush tables which are not write-locked as this breaks metadata locking protocol and thus potentially might lead to deadlock. - Added auxiliary adjust_mdl_locks_upgradability() function. sql/sql_partition.cc: Adjusted code to the fact that reopen_tables() no longer has "mark_share_as_old" argument. Got rid of comments which are no longer true. sql/sql_plist.h: Added I_P_List template class for parametrized intrusive doubly linked lists and I_P_List_iterator for corresponding iterator. Unlike for I_List<> list elements of such list can participate in several lists. Unlike List<> such lists are doubly-linked and intrusive. sql/sql_plugin.cc: Allocate metadata lock requests objects (MDL_LOCK) on execution memory root in cases when we use stack TABLE_LIST objects to open tables. sql/sql_prepare.cc: Replaced boolean TABLE_LIST::create member with enum open_table_type member. This allows easily handle situation in which instead of opening the table we want only to take exclusive metadata lock on it. sql/sql_rename.cc: Use new metadata locking subsystem in implementation of RENAME TABLE. sql/sql_servers.cc: Allocate metadata lock requests objects (MDL_LOCK) on execution memory root in cases when we use stack TABLE_LIST objects to open tables. Got rid of redundant code by using unlock_locked_tables() function. sql/sql_show.cc: Acquire shared metadata lock when we are getting information for I_S table directly from TABLE_SHARE without doing full-blown table open. We use high priority lock request in this situation in order to avoid deadlocks. Also allocate metadata lock requests objects (MDL_LOCK) on execution memory root in cases when TABLE_LIST objects are also allocated there sql/sql_table.cc: mysql_rm_table(): Removed comment which is no longer relevant. mysql_rm_table_part2(): Now caller of mysql_ha_rm_tables() should not own LOCK_open. Adjusted code to use new metadata locking subsystem instead of name-locks. lock_table_name_if_not_cached(): Moved this function from sql_base.cc to this file and reimplemented it using metadata locking API. mysql_create_table(): Adjusted code to use new MDL API. wait_while_table_is_used(): Changed function to use new MDL subsystem. Made thread waiting in it killable (this also led to introduction of return value so caller can distinguish successful executions from situations when waiting was aborted). close_cached_tables(): Thread waiting in this function is killable now. As result it has return value for distinguishing between succes and failure. Got rid of redundant boradcast_refresh() call. prepare_for_repair(): Use MDL subsystem instead of name-locks. mysql_admin_table(): mysql_ha_rm_tables() now always assumes that caller doesn't own LOCK_open. mysql_repair_table(): We should mark all elements of table list as requiring upgradable metadata locks. mysql_create_table_like(): Use new MDL subsystem instead of name-locks. create_temporary_tables(): We don't need to obtain metadata locks when creating temporary table. mysql_fast_or_online_alter_table(): Thread waiting in wait_while_table_is_used() is now killable. mysql_alter_table(): Adjusted code to work with new MDL subsystem and to the fact that threads waiting in what_while_table_is_used() and close_cached_table() are now killable. sql/sql_test.cc: We no longer have separate table cache. TABLE instances are now associated with/linked to TABLE_SHARE objects in table definition cache. sql/sql_trigger.cc: Adjusted code to work with new metadata locking subsystem. Also reopen_tables() no longer has mark_share_as_old argument (Instead of relying on this parameter and related behavior FLUSH TABLES WITH READ LOCK now takes global shared metadata lock). sql/sql_udf.cc: Allocate metadata lock requests objects (MDL_LOCK) on execution memory root in cases when we use stack TABLE_LIST objects to open tables. sql/sql_update.cc: Adjusted code to work with new meta-data locking subsystem. sql/sql_view.cc: Added proper meta-data locking to implementations of CREATE/ALTER/DROP VIEW statements. Now we obtain exclusive meta-data lock on a view before creating/ changing/dropping it. This ensures that all concurrent statements that use this view will finish before our statement will proceed and therefore we will get correct order of statements in the binary log. Also ensure that TABLE_LIST::mdl_upgradable attribute is properly propagated for underlying tables of view. sql/table.cc: Added auxiliary alloc_mdl_locks() function for allocating metadata lock request objects for all elements of table list. sql/table.h: TABLE_SHARE: Got rid of unused members. Introduced members for storing lists of used and unused TABLE objects for this share. TABLE: Added members for linking TABLE objects into per-share lists of used and unused TABLE instances. Added member for holding pointer to metadata lock for this table. TABLE_LIST: Replaced boolean TABLE_LIST::create member with enum open_table_type member. This allows easily handle situation in which instead of opening the table we want only to take exclusive meta-data lock on it (we need this in order to handle ALTER VIEW and CREATE VIEW statements). Introduced new mdl_upgradable member for marking elements of table list for which we need to take upgradable shared metadata lock instead of plain shared metadata lock. Added pointer for holding pointer to MDL_LOCK for the table. Added auxiliary alloc_mdl_locks() function for allocating metadata lock requests objects for all elements of table list. Added auxiliary set_all_mdl_upgradable() function for marking all elements in table list as requiring upgradable metadata locks. storage/myisammrg/ha_myisammrg.cc: Allocate MDL_LOCK objects for underlying tables of MERGE table. To be reworked once Ingo pushes his patch for WL4144.	16 years ago

11 Commits (a9013f8fbae943dc4d2b5bbd0f8005f0edb3cace)