1377 commits

Author	SHA1	Message	Date
Konstantin Osipov	dfdbc84585	A prerequisite patch for the fix for Bug#46224 ... "HANDLER statements within a transaction might lead to deadlocks". Introduce a notion of a sentinel to MDL_context. A sentinel is a ticket that separates all tickets in the context into two groups: before and after it. Currently we can have (and need) only one designated sentinel -- it separates all locks taken by LOCK TABLE or HANDLER statement, which must survive COMMIT and ROLLBACK and all other locks, which must be released at COMMIT or ROLLBACK. The tricky part is maintaining the sentinel up to date when someone release its corresponding ticket. This can happen, e.g. if someone issues DROP TABLE under LOCK TABLES (generally, see all calls to release_all_locks_for_name()). MDL_context::release_ticket() is modified to take care of it. ****** A fix and a test case for Bug#46224 "HANDLER statements within a transaction might lead to deadlocks". An attempt to mix HANDLER SQL statements, which are transaction- agnostic, an open multi-statement transaction, and DDL against the involved tables (in a concurrent connection) could lead to a deadlock. The deadlock would occur when HANDLER OPEN or HANDLER READ would have to wait on a conflicting metadata lock. If the connection that issued HANDLER statement also had other metadata locks (say, acquired in scope of a transaction), a classical deadlock situation of mutual wait could occur. Incompatible change: entering LOCK TABLES mode automatically closes all open HANDLERs in the current connection. Incompatible change: previously an attempt to wait on a lock in a connection that has an open HANDLER statement could wait indefinitely/deadlock. After this patch, an error ER_LOCK_DEADLOCK is produced. The idea of the fix is to merge thd->handler_mdl_context with the main mdl_context of the connection, used for transactional locks. This makes deadlock detection possible, since all waits with locks are "visible" and available to analysis in a single MDL context of the connection. Since HANDLER locks and transactional locks have a different life cycle -- HANDLERs are explicitly open and closed, and so are HANDLER locks, explicitly acquired and released, whereas transactional locks "accumulate" till the end of a transaction and are released only with COMMIT, ROLLBACK and ROLLBACK TO SAVEPOINT, a concept of "sentinel" was introduced to MDL_context. All locks, HANDLER and others, reside in the same linked list. However, a selected element of the list separates locks with different life cycle. HANDLER locks always reside at the end of the list, after the sentinel. Transactional locks are prepended to the beginning of the list, before the sentinel. Thus, ROLLBACK, COMMIT or ROLLBACK TO SAVEPOINT, only release those locks that reside before the sentinel. HANDLER locks must be released explicitly as part of HANDLER CLOSE statement, or an implicit close. The same approach with sentinel is also employed for LOCK TABLES locks. Since HANDLER and LOCK TABLES statement has never worked together, the implementation is made simple and only maintains one sentinel, which is used either for HANDLER locks, or for LOCK TABLES locks. mysql-test/include/handler.inc: Add test coverage for Bug#46224 "HANDLER statements within a transaction might lead to deadlocks". Extended HANDLER coverage to cover a mix of HANDLER, transactions and DDL statements. mysql-test/r/handler_innodb.result: Update results (Bug#46224). mysql-test/r/handler_myisam.result: Update results (Bug#46224). sql/lock.cc: Remove thd->some_tables_deleted, it's never used. sql/log_event.cc: No need to check for thd->locked_tables_mode, it's done inside release_transactional_locks(). sql/mdl.cc: Implement the concept of HANDLER and LOCK TABLES "sentinel". Implement a method to clone an acquired ticket. Do not return tickets beyond the sentinel when acquiring locks, create a copy. Remove methods to merge and backup MDL_context, they are now not used (Hurra!). This opens a path to a proper constructor and destructor of class MDL_context (to be done in a separate patch). Modify find_ticket() to provide information about where the ticket position is with regard to the sentinel. sql/mdl.h: Add declarations necessary for the implementation of the concept of "sentinel", a dedicated ticket separating transactional and non-transactional locks. sql/mysql_priv.h: Add mark_tmp_table_for_reuse() declaration, a function to "close" a single session (temporary) table. sql/sql_base.cc: Remove thd->some_tables_deleted. Modify deadlock-prevention asserts and deadlock detection heuristics to take into account that from now on HANDLER locks reside in the same locking context. Add broadcast_refresh() to mysql_notify_thread_having_shared_lock(): this is necessary for the case when a thread having a shared lock is asleep in tdc_wait_for_old_versions(). This situation is only possible with HANDLER t1 OPEN; FLUSH TABLE (since all over code paths that lead to tdc_wait_for_old_versions() always have an empty MDL_context). Previously the server would simply deadlock in this situation. sql/sql_class.cc: Remove now unused member "THD::some_tables_deleted". Move mysql_ha_cleanup() a few lines above in THD::cleanup() to make sure that all handlers are closed when it's time to destroy the MDL_context of this connection. Remove handler_mdl_context and handler_tables. sql/sql_class.h: Remove THD::handler_tables, THD::handler_mdl_context, THD::some_tables_deleted. sql/sql_handler.cc: Remove thd->handler_tables. Remove thd->handler_mdl_context. Rewrite mysql_ha_open() to have no special provision for MERGE tables, now that we don't have to manipulate with thd->handler_tables it's easy to do. Remove dead code. Fix a bug in mysql_ha_flush() when we would always flush a temporary HANDLER when mysql_ha_flush() is called (actually mysql_ha_flush() never needs to flush temporary tables). sql/sql_insert.cc: Update a comment, no more thd->some_tables_deleted. sql/sql_parse.cc: Implement an incompatible change: entering LOCK TABLES closes active HANDLERs, if any. Now that we have a sentinel, we don't need to check for thd->locked_tables_mode when releasing metadata locks in COMMIT/ROLLBACK. sql/sql_plist.h: Add new (now necessary) methods to the list class. sql/sql_prepare.cc: Make sure we don't release HANDLER locks when rollback to a savepoint, set to not keep locks taken at PREPARE. sql/sql_servers.cc: Update to a new signature of MDL_context::release_all_locks(). sql/sql_table.cc: Remove thd->some_tables_deleted. sql/transaction.cc: Add comments. Make sure rollback to (MDL) savepoint works under LOCK TABLES and with HANDLER tables.	2009-12-22 19:09:15 +03:00
Jon Olav Hauglid	6d4e09d68e	Bug #48541 Deadlock between LOCK_open and LOCK_mdl ... The reason for the deadlock was an improper exit from MDL_context::wait_for_locks() which caused mysys_var->current_mutex to remain LOCK_mdl even though LOCK_mdl was no longer held by that connection. This could for example lead to a deadlock in the following way: 1) INSERT DELAYED tries to open a table but fails, and trying to recover it calls wait_for_locks(). 2) Due to a pending exclusive request, wait_for_locks() fails and exits without resetting mysys_var->current_mutex for the delayed insert handler thread. So it continues to point to LOCK_mdl. 3) The handler thread manages to open a table. 4) A different connection takes LOCK_open and tries to take LOCK_mdl. 5) FLUSH TABLES from a third connection notices that the handler thread has a table open, and tries to kill it. This involves locking mysys_var->current_mutex while having LOCK_open locked. Since current_mutex mistakenly points to LOCK_mdl, we have a deadlock. This patch makes sure MDL_EXIT_COND() is called before exiting wait_for_locks(). This clears mysys->current_mutex which resolves the issue. An assert is added to recover_from_failed_open_table_attempt() after wait_for_locks() is called, to check that current_mutex is indeed reset. With this assert in place, existing tests in (e.g.) mdl_sync.test will fail without this patch.	2009-12-16 12:32:11 +01:00
Konstantin Osipov	980e8b413e	Merge next-mr -> next-4284.	2009-12-16 11:33:54 +03:00
Konstantin Osipov	3097c22afd	Backport of: ... ----------------------------------------------------------- 2630.28.28 Magne Mahre 2008-12-05 Bug #38661 'all threads hang in "opening tables" or "waiting for table" and cpu is at 100%' Concurrent execution of FLUSH TABLES statement and at least two statements using the same table might have led to live-lock which caused all three connections to stall and hog 100% of CPU. tdc_wait_for_old_versions() wrongly assumed that there cannot be a share with an old version and no used TABLE instances and thus was failing to perform wait in situation when such old share was cached in MDL subsystem thanks to a still active metadata lock on the table. So it might have happened that two or more connections simultaneously executing statements which involve table being flushed managed to prevent each other from waiting in this function by keeping shared metadata lock on the table constantly active (i.e. one of the statements managed to take/hold this lock while other statements were calling tdc_wait_for_old_versions()). Thus they were forcing each other to loop infinitely in open_tables() - close_thread_tables_for_reopen() - tdc_wait_for_old_versions() cycle causing CPU hogging. This patch fixes this problem by removing this false assumption from tdc_wait_for_old_versions(). Note that the problem is specific only for server versions >= 6.0. No test case is submitted for this test, as the test infrastructure hasn't got the necessary primitives to test the behaviour. The manifestation is that throughput will decrease to a low level (possibly 0) after some time, and stay at that level. Several transactions will not complete. Manual testing can be done by running the code submitted by Shane Bester attached to the bug report. If the bug persists, the transaction thruput will almost immediately drop to near zero (shown as the transaction count output from the test program staying on a close to constant value, instead of increasing rapidly).	2009-12-11 14:18:59 +03:00
Konstantin Osipov	1a122dc220	Partial backport of: ... ---------------------------------------------------- 2736.2.10 Michael Widenius 2008-10-22 Fix for bug#39395 Maria: ma_extra.c:286: maria_extra: Assertion `share->reopen == 1' failed sql/sql_base.cc: Race condition in wait_while_table_is_used() where a table used by another connection could be forced closed, but there was no protection against the other thread re-opening the table and trying to lock it again before the table was name locked by original thread.	2009-12-11 14:07:38 +03:00
Konstantin Osipov	b89c882c5d	Merge with next-4284.	2009-12-11 13:39:45 +03:00
Magne Mahre	16f3151570	Bug#41425 Assertion in Protocol::end_statement() (pushbuild2) ... (diagnostics_area) Execution of CREATE TABLE ... SELECT statement was not atomic in the sense that concurrent statements trying to affect its target table might have sneaked in between the moment when the table was created and moment when it was filled according to SELECT clause. This resulted in inconsistent binary log, unexpected target table contents. In cases when concurrent statement was a DDL statement CREATE TABLE ... SELECT might have failed with ER_CANT_LOCK error. In more detail: Due to premature metadata lock downgrade which occured after CREATE TABLE SELECT statement created table but before it managed to obtain table-level lock on it other statements were allowed to open, lock and change target table in the middle of CREATE TABLE SELECT execution. This also meant that it was possible that CREATE TABLE SELECT would wait in mysql_lock_tables() when it was called for newly created table and that this wait could have been aborted by concurrent DDL. The latter led to execution of unexpected branch of code and CREATE TABLE SELECT ending with ER_CANT_LOCK error. The premature downgrade occured because open_table(), which was called for newly created table, decided that it is OK to downgrade metadata lock from exclusive to shared since table exists, even although it was not acquired within this call. This fix ensures that open_table() does not downgrade metadata lock if it is not acquired during its current invocation. Testing: The bug is exposed in a race condition, and is thus difficult to expose in a standard mysql-test-run test case. Instead, a stress test using the Random Query Generator (https://launchpad.net/randgen) will trip the problem occasionally. % perl runall.pl \ --basedir=<build dir> \ --mysqld=--table-lock-wait-timeout=5 \ --mysqld=--skip-safemalloc \ --grammar=conf/maria_bulk_insert.yy \ --reporters=ErrorLog,Backtrace,WinPackage \ --mysqld=--log-output=file \ --queries=100000 \ --threads=10 \ --engine=myisam Note: You will need a debug build to expose the bug When the bug is tripped, the server will abort and dump core. Backport from 6.0-codebase (revid: 2617.53.4)	2009-12-10 15:49:15 +01:00
Konstantin Osipov	2f7a8770a9	Backport of: ... 2630.16.14 Sergei Golubchik 2008-08-25 fixed a crash in partition tests introduced by HA_EXTRA_PREPARE_FOR_DROP patch sql/sql_base.cc: Don't call ::extra() for closed tables.	2009-12-10 16:43:04 +03:00
Jon Olav Hauglid	fb6b5ee462	Backport of revno: 2617.68.37 ... Bug #46654 False deadlock on concurrent DML/DDL with partitions, inconsistent behavior The problem was that if one connection is running a multi-statement transaction which involves a single partitioned table, and another connection attempts to alter the table, the first connection gets ER_LOCK_DEADLOCK and cannot proceed anymore, even when the ALTER TABLE statement in another connection has timed out or failed. The reason for this was that the prepare phase for ALTER TABLE for partitioned tables removed all instances of the table from the table definition cache before it started waiting on the lock. The transaction running in the first connection would notice this and report ER_LOCK_DEADLOCK. This patch changes the prep_alter_part_table() ALTER TABLE code so that tdc_remove_table() is no longer called. Instead, only the TABLE instance changed by prep_alter_part_table() is marked as needing reopen. The patch also removes an unnecessary call to tdc_remove_table() from mysql_unpack_partition() as the changed TABLE object is destroyed by the caller at a later point. Test case added in partition_sync.test.	2009-12-10 14:26:00 +01:00
Jon Olav Hauglid	5e1dfa4c06	Backport of revno: 2617.71.1 ... Bug#42546 Backup: RESTORE fails, thinking it finds an existing table The problem occured when a MDL locking conflict happened for a non-existent table between a CREATE and a INSERT statement. The code for CREATE interpreted this lock conflict to mean that the table existed, which meant that the statement failed when it should not have. The problem could occur for CREATE TABLE, CREATE TABLE LIKE and ALTER TABLE RENAME. This patch fixes the problem for CREATE TABLE and CREATE TABLE LIKE. It is based on code backported from the mysql-6.1-fk tree written by Dmitry Lenev. CREATE now uses normal open_and_lock_tables() code to acquire exclusive locks. This means that for the test case in the bug description, CREATE will wait until INSERT completes so that it can get the exclusive lock. This resolves the reported bug. The patch also prohibits CREATE TABLE and CREATE TABLE LIKE under LOCK TABLES. Note that this is an incompatible change and must be reflected in the documentation. Affected test cases have been updated. mdl_sync.test contains tests for CREATE TABLE and CREATE TABLE LIKE. Fixing the issue for ALTER TABLE RENAME is beyond the scope of this patch. ALTER TABLE cannot be prohibited from working under LOCK TABLES as this could seriously impact customers and a proper fix would require a significant rewrite.	2009-12-10 11:53:20 +01:00
Konstantin Osipov	f26f632b44	Backport of: ... ------------------------------------------------------------ revno: 2617.68.25 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-next-bg-pre2-2 timestamp: Wed 2009-09-16 18:26:50 +0400 message: Follow-up for one of pre-requisite patches for fixing bug #30977 "Concurrent statement using stored function and DROP FUNCTION breaks SBR". Made enum_mdl_namespace enum part of MDL_key class and removed MDL_ prefix from the names of enum members. In order to do the latter changed name of PROCEDURE symbol to PROCEDURE_SYM (otherwise macro which was automatically generated for this symbol conflicted with MDL_key::PROCEDURE enum member).	2009-12-10 11:21:38 +03:00
Konstantin Osipov	634a810942	Backport of: ... ------------------------------------------------------------ revno: 2617.68.24 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-next-bg-pre2-2 timestamp: Wed 2009-09-16 17:25:29 +0400 message: Pre-requisite patch for fixing bug #30977 "Concurrent statement using stored function and DROP FUNCTION breaks SBR". Added MDL_request for stored routine as member to Sroutine_hash_entry in order to be able perform metadata locking for stored routines in future (Sroutine_hash_entry is an equivalent of TABLE_LIST class for stored routines). (WL#4284, follow up fixes). sql/mdl.cc: Introduced version of MDL_request::init() method which initializes lock request using pre-built MDL key. MDL_key::table_name/table_name_length() getters were renamed to reflect the fact that MDL_key objects are now created not only for tables. sql/mdl.h: Extended enum_mdl_namespace enum with values which correspond to namespaces for stored functions and triggers. Renamed MDL_key::table_name/table_name_length() getters to MDL_key::name() and name_length() correspondingly to reflect the fact that MDL_key objects are now created not only for tables. Added MDL_key::mdl_namespace() getter. Also added version of MDL_request::init() method which initializes lock request using pre-built MDL key. sql/sp.cc: Added MDL_request for stored routine as member to Sroutine_hash_entry. Changed code to use MDL_key from this request as a key for LEX::sroutines set. Removed separate "key" member from Sroutine_hash_entry as it became unnecessary. sql/sp.h: Added MDL_request for stored routine as member to Sroutine_hash_entry in order to be able perform metadata locking for stored routines in future (Sroutine_hash_entry is an equivalent of TABLE_LIST class for stored routines). Removed Sroutine_hash_entry::key member as now we can use MDL_key from this request as a key for LEX::sroutines set. sql/sp_head.cc: Removed sp_name::m_sroutines_key member and set_routine_type() method. Since key for routine in LEX::sroutines set has no longer sp_name::m_qname as suffix we won't save anything by creating it at sp_name construction time. Adjusted sp_name constructor used for creating temporary objects for lookups in SP-cache to accept MDL_key as parameter and to avoid any memory allocation. Finally, removed sp_head::m_soutines_key member for reasons similar to why sp_name::m_sroutines_key was removed sql/sp_head.h: Removed sp_name::m_sroutines_key member and set_routine_type() method. Since key for routine in LEX::sroutines set has no longer sp_name::m_qname as suffix we won't save anything by creating it at sp_name construction time. Adjusted sp_name constructor used for creating temporary objects for lookups in SP-cache to accept MDL_key as parameter and to avoid any memory allocation. Finally, removed sp_head::m_soutines_key member for reasons similar to why sp_name::m_sroutines_key was removed. sql/sql_base.cc: Adjusted code to the fact that we now use MDL_key from Sroutine_hash_entry::mdl_request as a key for LEX::sroutines set. MDL_key::table_name/table_name_length() getters were renamed to reflect the fact that MDL_key objects are now created not only for tables. sql/sql_trigger.cc: sp_add_used_routine() now takes MDL_key as parameter as now we use instance of this class as a key for LEX::sroutines set.	2009-12-09 19:11:26 +03:00
Konstantin Osipov	b9d2f55a9d	------------------------------------------------------------ ... revno: 2617.68.23 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-next-bg-pre1 timestamp: Wed 2009-09-16 09:34:42 +0400 message: Pre-requisite patch for fixing bug #30977 "Concurrent statement using stored function and DROP FUNCTION breaks SBR". CREATE TABLE SELECT statements take exclusive metadata lock on table being created. Invariant of metadata locking subsystem states that such lock should be taken before taking any kind of shared locks. Once metadata locks on stored routines are introduced statements like "CREATE TABLE ... SELECT f1()" will break this invariant by taking shared locks on routines before exclusive lock on target table. To avoid this, open_tables() is reworked to process tables which are directly used by the statement before stored routines are processed. sql/sql_base.cc: Refactored open_tables() implementation to process stored routines only after tables which are directly used by statement were processed. To achieve this moved handling of routines in open_tables() out of loop which iterates over tables to a new separate loop. And in its turn this allowed to split handling of particular table or view to an auxiliary function, which made code in open_tables() simpler and more easy to understand.	2009-12-09 19:00:46 +03:00
Konstantin Osipov	e001a9f0d0	Backport of: ... ------------------------------------------------------------ revno: 2617.68.10 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-next-bg46673 timestamp: Tue 2009-09-01 19:57:05 +0400 message: Fix for bug #46673 "Deadlock between FLUSH TABLES WITH READ LOCK and DML". Deadlocks occured when one concurrently executed transactions with several statements modifying data and FLUSH TABLES WITH READ LOCK statement or SET READ_ONLY=1 statement. These deadlocks were introduced by the patch for WL 4284: "Transactional DDL locking"/Bug 989: "If DROP TABLE while there's an active transaction, wrong binlog order" which has changed FLUSH TABLES WITH READ LOCK/SET READ_ONLY=1 to wait for pending transactions. What happened was that FLUSH TABLES WITH READ LOCK blocked all further statements changing tables by setting global_read_lock global variable and has started waiting for all pending transactions to complete. Then one of those transactions tried to executed DML, detected that global_read_lock non-zero and tried to wait until global read lock will be released (i.e. global_read_lock becomes 0), indeed, this led to a deadlock. Proper solution for this problem should probably involve full integration of global read lock with metadata locking subsystem (which will allow to implement waiting for pending transactions without blocking DML in them). But since it requires significant changes another, short-term solution for the problem is implemented in this patch. Basically, this patch restores behavior of FLUSH TABLES WITH READ LOCK/ SET READ_ONLY=1 before the patch for WL 4284/bug 989. By ensuring that extra references to TABLE_SHARE are not stored for active metadata locks it changes these statements not to wait for pending transactions. As result deadlock is eliminated. Note that this does not change the fact that active FLUSH TABLES WITH READ LOCK lock or SET READ_ONLY=1 prevent modifications to tables as they also block transaction commits. mysql-test/r/flush_block_commit.result: Adjusted test case after change in FLUSH TABLES WITH READ LOCK behavior - it is no longer blocked by a pending transaction. mysql-test/r/mdl_sync.result: Added test for bug #46673 "Deadlock between FLUSH TABLES WITH READ LOCK and DML". mysql-test/r/read_only_innodb.result: Adjusted test case after change in SET READ_ONLY behavior - it is no longer blocked by a pending transaction. mysql-test/t/flush_block_commit.test: Adjusted test case after change in FLUSH TABLES WITH READ LOCK behavior - it is no longer blocked by a pending transaction. mysql-test/t/mdl_sync.test: Added test for bug #46673 "Deadlock between FLUSH TABLES WITH READ LOCK and DML". mysql-test/t/read_only_innodb.test: Adjusted test case after change in SET READ_ONLY behavior - it is no longer blocked by a pending transaction. sql/sql_base.cc: Disable caching of pointers to TABLE_SHARE objects in MDL subsystem. This means that transactions holding metadata lock on the table will no longer have extra reference to the TABLE_SHARE (due to this lock) and will no longer block concurrent FLUSH TABLES/FLUSH TABLES WITH READ LOCK. Note that this does not change the fact that FLUSH TABLES WITH READ LOCK prevents concurrent transactions from modifying data as it also blocks all commits.	2009-12-09 18:56:34 +03:00
Konstantin Osipov	2f26574026	Backport of: ... ------------------------------------------------------------ revno: 2617.68.7 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-next-bg46044 timestamp: Thu 2009-08-27 10:22:17 +0400 message: Fix for bug #46044 "MDL deadlock on LOCK TABLE + CREATE TABLE HIGH_PRIORITY FOR UPDATE". Deadlock occured when during execution of query to I_S we tried to open a table or its .FRM in order to get information about it and had to wait because we have encountered exclusive metadata lock on this table held by a DDL operation from another connection which in its turn waited for some resource currently owned by connection executing this I_S query. For example, this might have happened if one under LOCK TABLES executed I_S query targeted to particular table (which was not among locked) and also concurrently tried to create this table using CREATE TABLE SELECT which had to wait for one of tables locked by the first connection. Another situation in which deadlock might have occured is when I_S query, which was executed as part of transaction, tried to get information about table which just has been dropped by concurrent DROP TABLES executed under LOCK TABLES and this DROP TABLES for its completion also had to wait transaction from the first connection. This problem stemmed from the fact that opening of tables/.FRMs for I_S filling is happening outside of connection's main MDL_context so code which tries to detect deadlocks due to conflicting metadata locks doesn't work in this case. Indeed, this led to deadlocks when during I_S filling we tried to wait for conflicting metadata lock to go away, while its owner was waiting for some resource held by connection executing I_S query. This patch solves this problem by avoiding waiting in such situation. Instead we skip this table and produce warning that information about it was omitted from I_S due to concurrent DDL operation. We still wait for conflicting metadata lock to go away when it is known that deadlock is not possible (i.e. when connection executing I_S query does not hold any metadata or table-level locks). Basically, we apply our standard deadlock avoidance technique for metadata locks to the process of filling of I_S tables but replace ER_LOCK_DEADLOCK error with a warning. Note that this change is supposed to be safe for 'mysqldump' since the only its mode which is affected by this change is --single-transaction mode is not safe in the presence of concurrent DDL anyway (and this fact is documented). Other modes are unaffected because they either use SHOW TABLES/SELECT * FROM I_S.TABLE_NAMES which do not take any metadata locks in the process of I_S table filling and thus cannot skip tables or execute I_S queries for tables which were previously locked by LOCK TABLES (or in the presence of global read lock) which excludes possibility of encountering conflicting metadata lock. mysql-test/r/mdl_sync.result: Added test for bug #46044 "MDL deadlock on LOCK TABLE + CREATE TABLE HIGH_PRIORITY FOR UPDATE". mysql-test/t/mdl_sync.test: Added test for bug #46044 "MDL deadlock on LOCK TABLE + CREATE TABLE HIGH_PRIORITY FOR UPDATE". sql/mysql_priv.h: Added a new flag for open_table() call which allows it to fail with an error in cases when conflicting metadata lock is discovered instead of waiting until this lock goes away. sql/share/errmsg-utf8.txt: Added error/warning message to be generated in cases when information about table is omitted from I_S since there is conflicting metadata lock on the table. sql/share/errmsg.txt: Added error/warning message to be generated in cases when information about table is omitted from I_S since there is conflicting metadata lock on the table. sql/sql_base.cc: Added a new flag for open_table() call which allows it to fail with an error in cases when conflicting metadata lock is discovered instead of waiting until this lock goes away. sql/sql_show.cc: When we are opening a table (or just .FRM) in order to fill I_S with information about this table and encounter conflicting metadata lock waiting for this lock to go away can lead to a deadlock in some situations (under LOCK TABLES, within transaction, etc.). To avoid these deadlocks we detect such situations and don't do waiting. Instead, we skip table for which we have conflicting metadata lock, thus omitting information about it from I_S table, and produce an appropriate warning.	2009-12-09 18:48:42 +03:00
Konstantin Osipov	d6aaa5fd51	Merge.	2009-12-09 12:46:13 +03:00
Konstantin Osipov	736db89a76	Backport of: ... ------------------------------------------------------------ revno: 2617.69.37 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-next-bg46748 timestamp: Fri 2009-08-21 18:17:02 +0400 message: Fix for bug #46748 "Assertion in MDL_context::wait_for_locks() on INSERT + CREATE TRIGGER". Concurrent execution of statements involving stored functions or triggers which were using several tables and DDL statements which affected those tables on debug build of server might have led to assertion failures in MDL_context::wait_for_locks(). Non-debug build was not affected. The problem was that during back-off which happens when open_tables() encounters conflicting metadata lock for one of the tables being open we didn't reset MDL_request::ticket value for requests which correspond to tables from extended prelocking set. Since these requests are part of of list of requests to be waited for in Open_table_context this broke assumption that ticket value for them is 0 in MDL_context::wait_for_locks() and caused assertion failure. This fix ensures that close_tables_for_reopen(), which performs this back-off resets MDL_request::ticket value not only for tables directly used by the statement but also for tables from extended prelocking set, thus satisfying assumption described above. mysql-test/r/mdl_sync.result: Added test case for bug #46748 "Assertion in MDL_context::wait_for_locks() on INSERT + CREATE TRIGGER". mysql-test/t/mdl_sync.test: Added test case for bug #46748 "Assertion in MDL_context::wait_for_locks() on INSERT + CREATE TRIGGER". sql/sql_base.cc: Since metadata lock requests for tables from extended part of prelocking set are also part of list of requests to be waited for in Open_table_context in close_tables_for_reopen() we have to reset MDL_request::ticket values for them to assumptions in MDL_context::wait_for_locks().	2009-12-09 12:44:05 +03:00
Jon Olav Hauglid	fcae99271a	Backport of revno: 2617.68.39 ... Bug #47249 assert in MDL_global_lock::is_lock_type_compatible This assert could be triggered if LOCK TABLES were used to lock both a table and a view that used the same table. The table would have to be first WRITE locked and then READ locked. So "LOCK TABLES v1 WRITE, t1 READ" would eventually trigger the assert, "LOCK TABLES v1 READ, t1 WRITE" would not. The reason is that the ordering of locks in the interal representation made a difference when executing FLUSH TABLE on the table. During FLUSH TABLE, a lock was upgraded to exclusive. If this lock was of type MDL_SHARED and not MDL_SHARED_UPGRADABLE, an internal counter in the MDL subsystem would get out of sync. This would happen if the *last* mention of the table in LOCK TABLES was a READ lock. The counter in question is the number exclusive locks (active or intention). This is used to make sure a global metadata lock is only taken when the counter is zero (= no conflicts). The counter is increased when a MDL_EXCLUSIVE or MDL_SHARED_UPGRADABLE lock is taken, but not when upgrade_shared_lock_to_exclusive() is used to upgrade directly from MDL_SHARED to MDL_EXCLUSIVE. This patch fixes the problem by searching for a TABLE instance locked with MDL_SHARED_UPGRADABLE or MDL_EXCLUSIVE before calling upgrade_shared_lock_to_exclusive(). The patch also adds an assert checking that only MDL_SHARED_UPGRADABLE locks are upgraded to exclusive. Test case added to lock_multi.test.	2009-12-09 10:44:01 +01:00
Konstantin Osipov	351b912e85	Backport of: ... ---------------------------------------------------------- revno: 2617.69.25 committer: Konstantin Osipov <kostja@sun.com> branch nick: 5.4-42546 timestamp: Fri 2009-08-14 23:52:00 +0400 message: A cleanup in open_tables() and lock_tables(): change return type of these functions to bool from int, to follow convention in the rest of the code. (Part of WL#4284 review fixes). sql/mysql_priv.h: Change return type of open_talbes() and lock_tables() from int to bool. sql/sql_base.cc: Change return type of open_tables() and lock_tables() from int to bool. sql/sql_handler.cc: Use bool now that open_tables() returns bool.	2009-12-09 12:04:55 +03:00
Jon Olav Hauglid	546e16ebd8	Backport of revno: 2617.69.40 ... A pre-requisite patch for Bug#30977 "Concurrent statement using stored function and DROP FUNCTION breaks SBR". This patch changes the MDL API by introducing a namespace for lock keys: MDL_TABLE for tables and views and MDL_PROCEDURE for stored procedures and functions. The latter is needed for the fix for Bug#30977.	2009-12-09 09:51:20 +01:00
Konstantin Osipov	302352723e	Backport of: ... ---------------------------------------------------------- revno: 2617.69.24 committer: Konstantin Osipov <kostja@sun.com> branch nick: 5.4-42546 timestamp: Fri 2009-08-14 19:22:05 +0400 message: A pre-requisite for a fix for Bug#42546 "Backup: RESTORE fails, thinking it finds an existing table" Back-port from WL 148 "Foreign keys" feature tree a patch that introduced Prelocking_strategy class -- a way to parameterize open_tables() behaviour, implemented by Dmitry Lenev. (Part of WL#4284). sql/sql_base.cc: Implement different prelocking strategies. Use an instance of prelocking_strategy in open_tables(). sql/sql_class.h: Add declarations for class Prelocking_strategy. sql/sql_lex.h: Add a helper method to access last table of the global table list (lex->query_tables). sql/sql_parse.cc: Use a special prelocking strategy when locking tables for LOCK TABLES. sql/sql_table.cc: Use normal open_and_lock_tables_derived() in ALTER TABLE. sql/sql_yacc.yy: Modify the grammar to not pollute the global table list with tables that should not be opened.	2009-12-08 17:13:12 +03:00
Konstantin Osipov	ce5c87a3d3	Backport of: ... ---------------------------------------------------------- revno: 2617.69.20 committer: Konstantin Osipov <kostja@sun.com> branch nick: 5.4-4284-1-assert timestamp: Thu 2009-08-13 18:29:55 +0400 message: WL#4284 "Transactional DDL locking" A review fix. Since WL#4284 implementation separated MDL_request and MDL_ticket, MDL_request becamse a utility object necessary only to get a ticket. Store it by-value in TABLE_LIST with the intent to merge MDL_request::key with table_list->table_name and table_list->db in future. Change the MDL subsystem to not require MDL_requests to stay around till close_thread_tables(). Remove the list of requests from the MDL context. Requests for shared metadata locks acquired in open_tables() are only used as a list in recover_from_failed_open_table_attempt(), which calls mdl_context.wait_for_locks() for this list. To keep such list for recover_from_failed_open_table_attempt(), introduce a context class (Open_table_context), that collects all requests. A lot of minor cleanups and simplications that became possible with this change. sql/event_db_repository.cc: Remove alloc_mdl_requests(). Now MDL_request instance is a member of TABLE_LIST, and init_one_table() initializes it. sql/ha_ndbcluster_binlog.cc: Remove now unnecessary declaration and initialization of binlog_mdl_request. sql/lock.cc: No need to allocate MDL requests in lock_table_names() now. sql/log.cc: Use init_one_table() method, remove alloc_mdl_requests(), which is now unnecessary. sql/log_event.cc: No need to allocate mdl_request separately now. Use init_one_table() method. sql/log_event_old.cc: Update to the new signature of close_tables_for_reopen(). sql/mdl.cc: Update try_acquire_exclusive_lock() to be more easy to use. Function lock_table_name_if_not_cached() has been removed. Make acquire_shared_lock() signature consistent with try_acquire_exclusive_lock() signature. Remove methods that are no longer used. Update comments. sql/mdl.h: Implement an assignment operator that doesn't copy MDL_key (MDL_key::operator= is private and should remain private). This is a hack to work-around assignment of TABLE_LIST by value in several places. Such assignments violate encapsulation, since only perform a shallow copy. In most cases these assignments are a hack on their own. sql/mysql_priv.h: Update signatures of close_thread_tables() and close_tables_for_reopen(). sql/sp.cc: Allocate TABLE_LIST in thd->mem_root. Use init_one_table(). sql/sp_head.cc: Use init_one_table(). Remove thd->locked_tables_root, it's no longer needed. sql/sql_acl.cc: Use init_mdl_requests() and init_one_table(). sql/sql_base.cc: Update to new signatures of try_acquire_shared_lock() and try_acquire_exclusive_lock(). Remove lock_table_name_if_not_cached(). Fix a bug in open_ltable() that would not return ER_LOCK_DEADLOCK in case of a failed lock_tables() and a multi-statement transaction. Fix a bug in open_and_lock_tables_derived() that would not return ER_LOCK_DEADLOCK in case of a multi-statement transaction and a failure of lock_tables(). Move assignment of enum_open_table_action to a method of Open_table_context, a new class that maintains information for backoff actions. Minor rearrangements of the code. Remove alloc_mdl_requests() in functions that work with system tables: instead the patch ensures that callers always initialize TABLE_LIST argument. sql/sql_class.cc: THD::locked_tables_root is no more. sql/sql_class.h: THD::locked_tables_root is no more. Add a declaration for Open_table_context class. sql/sql_delete.cc: Update to use the simplified MDL API. sql/sql_handler.cc: TABLE_LIST::mdl_request is stored by-value now. Ensure that mdl_request.ticket is NULL for every request that is passed into MDL, to satisfy MDL asserts. @ sql/sql_help.cc Function open_system_tables_for_read() no longer initializes mdl_requests. Move TABLE_LIST::mdl_request initialization closer to TABLE_LIST initialization. sql/sql_help.cc: Function open_system_tables_for_read() no longer initializes mdl_requests. Move TABLE_LIST::mdl_request initialization closer to TABLE_LIST initialization. sql/sql_insert.cc: Remove assignment by-value of TABLE_LIST in TABLEOP_HOOKS. We can't carry over a granted MDL ticket from one table list to another. sql/sql_parse.cc: Change alloc_mdl_requests() -> init_mdl_requests(). @todo We can remove init_mdl_requests() altogether in some places: all places that call add_table_to_list() already have mdl requests initialized. sql/sql_plugin.cc: Use init_one_table(). THD::locked_tables_root is no more. sql/sql_servers.cc: Use init_one_table(). sql/sql_show.cc: Update acquire_high_priority_shared_lock() to use TABLE_LIST::mdl_request rather than allocate an own. Fix get_trigger_table_impl() to use init_one_table(), check for out of memory, follow the coding style. sql/sql_table.cc: Update to work with TABLE_LIST::mdl_request by-value. Remove lock_table_name_if_not_cached(). The code that used to delegate to it is quite simple and concise without it now. sql/sql_udf.cc: Use init_one_table(). sql/sql_update.cc: Update to use the new signature of close_tables_for_reopen(). sql/table.cc: Move re-setting of mdl_requests for prepared statements and stored procedures from close_thread_tables() to reinit_stmt_before_use(). Change alloc_mdl_requests() to init_mdl_requests(). init_mdl_requests() is a hack that can't be deleted until we don't have a list-aware TABLE_LIST constructor. Hopefully its use will be minimal sql/table.h: Change alloc_mdl_requests() to init_mdl_requests() TABLE_LIST::mdl_request is stored by value. sql/tztime.cc: We no longer initialize mdl requests in open_system_tables_for*() functions. Move this initialization closer to initialization of the rest of TABLE_LIST members. storage/myisammrg/ha_myisammrg.cc: Simplify mdl_request initialization.	2009-12-08 12:57:07 +03:00
Konstantin Osipov	478e09609c	Backport of: ... ---------------------------------------------------------- revno: 2617.69.2 committer: Konstantin Osipov <kostja@sun.com> branch nick: 5.4-azalea-bugfixing timestamp: Mon 2009-08-03 19:26:04 +0400 message: A fix and a test case for Bug#45035 "Altering table under LOCK TABLES results in "Error 1213 Deadlock found...". If a user had a table locked with LOCK TABLES for READ and for WRITE in the same connection, ALTER TABLE could fail. Root cause analysis: If a connection issues LOCK TABLE t1 write, t1 a read, t1 b read; the new LOCK TABLES code in 6.0 (part of WL 3726) will create the following list of TABLE_LIST objects (thd->locked_tables_list->m_locked_tables): {"t1" "b" tl_read_no_insert}, {"t1" "a" tl_read_no_insert}, {"t1" "t1" tl_write } Later on, when we try to ALTER table t1, mysql_alter_table() closes all TABLE instances and releases its thr_lock locks, keeping only an exclusive metadata lock on t1. But when ALTER is finished, Locked_table_list::reopen_tables() tries to restore the original list of open and locked tables. Before this patch, it used to do so one by one: Open t1 b, get TL_READ_NO_INSERT lock, Open t1 a, get TL_READ_NO_INSERT lock Open t1, try to get TL_WRITE lock, deadlock. The cause of the deadlock is that thr_lock.c doesn't resolve the situation when the read list only consists of locks taken by the same thread, followed by this very thread trying to take a WRITE lock. Indeed, since thr_lock_multi always gets a sorted list of locks, WRITE locks always precede READ locks in the list to lock. Don't try to fix thr_lock.c deficiency, keep this code simple. Instead, try to take all thr_lock locks at once in ::reopen_tables(). mysql-test/r/lock.result: Update results: test case for Bug#45035. mysql-test/t/lock.test: Add a test case for Bug#45035. sql/sql_base.cc: Take all thr_lock locks at once in Locked_tables_list::reopen_tables(). sql/sql_class.h: Add a helper array to store tables for mysql_lock_tables() in reopen_tables(). sql/sql_table.cc: Update unlink_all_closed_tables() to the new signature.	2009-12-08 11:38:45 +03:00
Konstantin Osipov	226d3e4f1e	Backport of: ... ------------------------------------------------------------ revno: 2617.65.6 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-azalea-bg39674 timestamp: Sat 2009-07-25 00:28:43 +0400 message: Fix for bug #39674 "On shutdown mdl_destroy() called before plugin_shutdown()". Attempt to shutdown PBXT engine plugin led to assertion failure caused by using already destroyed mutex in metadata locking subsystem. This problem stemmed from the fact that we MDL subsystem and table definition cache were deinitialized before plugin shutdown while PBXT plugin during its shutdown process accessed tables and therefore expected them to be in working shape. This patch solves this problem by moving deinitialization of these two subsystems after plugins are shut down. No test case is provided since such test case would require using PBXT or other plugin which accesses tables during its shutdown process. sql/mysql_priv.h: Introduced table_def_start_shutdown() function which informs table definition cache that shutdown process has been started so it has to keep number of TABLE and TABLE_SHARE objects minimal in order to reduce number of references to pluggable engines. sql/mysqld.cc: Destroy table definition cache and meta-data locking subsystem after shutting down plugins. This allows plugins to work with tables during their shutdown. Since table definition cache hold references to storage engine plugins we have to remove unused tables from it before shutting down plugins and keep number of these references minimal during the process (by immediately removing tables opened during this process from the table definition cache). sql/sql_base.cc: Introduced table_def_start_shutdown() function which informs table definition cache that shutdown process has been started so it has to keep number of TABLE and TABLE_SHARE objects minimal in order to reduce number of references to pluggable engines. This allows to smoothly shutdown such plugins without completely prohibiting access to tables/table definition cache while shutting down other plugins.	2009-12-08 11:26:49 +03:00
Konstantin Osipov	a14bbee5ab	Backport of revno ## 2617.31.1, 2617.31.3, 2617.31.4, 2617.31.5, ... 2617.31.12, 2617.31.15, 2617.31.15, 2617.31.16, 2617.43.1 - initial changeset that introduced the fix for Bug#989 and follow up fixes for all test suite failures introduced in the initial changeset. ------------------------------------------------------------ revno: 2617.31.1 committer: Davi Arnaut <Davi.Arnaut@Sun.COM> branch nick: 4284-6.0 timestamp: Fri 2009-03-06 19:17:00 -0300 message: Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order WL#4284: Transactional DDL locking Currently the MySQL server does not keep metadata locks on schema objects for the duration of a transaction, thus failing to guarantee the integrity of the schema objects being used during the transaction and to protect then from concurrent DDL operations. This also poses a problem for replication as a DDL operation might be replicated even thought there are active transactions using the object being modified. The solution is to defer the release of metadata locks until a active transaction is either committed or rolled back. This prevents other statements from modifying the table for the entire duration of the transaction. This provides commitment ordering for guaranteeing serializability across multiple transactions. - Incompatible change: If MySQL's metadata locking system encounters a lock conflict, the usual schema is to use the try and back-off technique to avoid deadlocks -- this schema consists in releasing all locks and trying to acquire them all in one go. But in a transactional context this algorithm can't be utilized as its not possible to release locks acquired during the course of the transaction without breaking the transaction commitments. To avoid deadlocks in this case, the ER_LOCK_DEADLOCK will be returned if a lock conflict is encountered during a transaction. Let's consider an example: A transaction has two statements that modify table t1, then table t2, and then commits. The first statement of the transaction will acquire a shared metadata lock on table t1, and it will be kept utill COMMIT to ensure serializability. At the moment when the second statement attempts to acquire a shared metadata lock on t2, a concurrent ALTER or DROP statement might have locked t2 exclusively. The prescription of the current locking protocol is that the acquirer of the shared lock backs off -- gives up all his current locks and retries. This implies that the entire multi-statement transaction has to be rolled back. - Incompatible change: FLUSH commands such as FLUSH PRIVILEGES and FLUSH TABLES WITH READ LOCK won't cause locked tables to be implicitly unlocked anymore. mysql-test/extra/binlog_tests/drop_table.test: Add test case for Bug#989. mysql-test/extra/binlog_tests/mix_innodb_myisam_binlog.test: Fix test case to reflect the fact that transactions now hold metadata locks for the duration of a transaction. mysql-test/include/mix1.inc: Fix test case to reflect the fact that transactions now hold metadata locks for the duration of a transaction. mysql-test/include/mix2.inc: Fix test case to reflect the fact that transactions now hold metadata locks for the duration of a transaction. mysql-test/r/flush_block_commit.result: Update test case result (WL#4284). mysql-test/r/flush_block_commit_notembedded.result: Update test case result (WL#4284). mysql-test/r/innodb.result: Update test case result (WL#4284). mysql-test/r/innodb_mysql.result: Update test case result (WL#4284). mysql-test/r/lock.result: Add test case result for an effect of WL#4284/Bug#989 (all locks should be released when a connection terminates). mysql-test/r/mix2_myisam.result: Update test case result (effects of WL#4284/Bug#989). mysql-test/r/not_embedded_server.result: Update test case result (effects of WL#4284/Bug#989). Add a test case for interaction of WL#4284 and FLUSH PRIVILEGES. mysql-test/r/partition_innodb_semi_consistent.result: Update test case result (effects of WL#4284/Bug#989). mysql-test/r/partition_sync.result: Temporarily disable the test case for Bug#43867, which will be fixed by a subsequent backport. mysql-test/r/ps.result: Add a test case for effect of PREPARE on transactional locks: we take a savepoint at beginning of PREAPRE and release it at the end. Thus PREPARE does not accumulate metadata locks (Bug#989/WL#4284). mysql-test/r/read_only_innodb.result: Update test case result (effects of WL#4284/Bug#989). mysql-test/suite/binlog/r/binlog_row_drop_tbl.result: Add a test case result (WL#4284/Bug#989). mysql-test/suite/binlog/r/binlog_row_mix_innodb_myisam.result: Update test case result (effects of WL#4284/Bug#989). mysql-test/suite/binlog/r/binlog_stm_drop_tbl.result: Add a test case result (WL#4284/Bug#989). mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result: Update test case result (effects of WL#4284/Bug#989). mysql-test/suite/binlog/r/binlog_unsafe.result: A side effect of Bug#989 -- slightly different table map ids. mysql-test/suite/binlog/t/binlog_row_drop_tbl.test: Add a test case for WL#4284/Bug#989. mysql-test/suite/binlog/t/binlog_stm_drop_tbl.test: Add a test case for WL#4284/Bug#989. mysql-test/suite/binlog/t/binlog_stm_row.test: Update to the new state name. This is actually a follow up to another patch for WL#4284, that changes Locked thread state to Table lock. mysql-test/suite/ndb/r/ndb_index_ordered.result: Remove result for disabled part of the test case. mysql-test/suite/ndb/t/disabled.def: Temporarily disable a test case (Bug#45621). mysql-test/suite/ndb/t/ndb_index_ordered.test: Disable a part of a test case (needs update to reflect semantics of Bug#989). mysql-test/suite/rpl/t/disabled.def: Disable tests made meaningless by transactional metadata locking. mysql-test/suite/sys_vars/r/autocommit_func.result: Add a commit (Bug#989). mysql-test/suite/sys_vars/t/autocommit_func.test: Add a commit (Bug#989). mysql-test/t/flush_block_commit.test: Fix test case to reflect the fact that transactions now hold metadata locks for the duration of a transaction. mysql-test/t/flush_block_commit_notembedded.test: Fix test case to reflect the fact that transactions now hold metadata locks for the duration of a transaction. Add a test case for transaction-scope locks and the global read lock (Bug#989/WL#4284). mysql-test/t/innodb.test: Fix test case to reflect the fact that transactions now hold metadata locks for the duration of a transaction (effects of Bug#989/WL#4284). mysql-test/t/lock.test: Add a test case for Bug#989/WL#4284. mysql-test/t/not_embedded_server.test: Add a test case for Bug#989/WL#4284. mysql-test/t/partition_innodb_semi_consistent.test: Replace TRUNCATE with DELETE, to not issue an implicit commit of a transaction, and not depend on metadata locks. mysql-test/t/partition_sync.test: Temporarily disable the test case for Bug#43867, which needs a fix to be backported from 6.0. mysql-test/t/ps.test: Add a test case for semantics of PREPARE and transaction-scope locks: metadata locks on tables used in PREPARE are enclosed into a temporary savepoint, taken at the beginning of PREPARE, and released at the end. Thus PREPARE does not effect what locks a transaction owns. mysql-test/t/read_only_innodb.test: Fix test case to reflect the fact that transactions now hold metadata locks for the duration of a transaction (Bug#989/WL#4284). Wait for the read_only statement to actually flush tables before sending other concurrent statements that depend on its state. mysql-test/t/xa.test: Fix test case to reflect the fact that transactions now hold metadata locks for the duration of a transaction (Bug#989/WL#4284). sql/ha_ndbcluster_binlog.cc: Backport bits of changes of ha_ndbcluster_binlog.cc from 6.0, to fix the failing binlog test suite with WL#4284. WL#4284 implementation does not work with 5.1 implementation of ndbcluster binlog index. sql/log_event.cc: Release metadata locks after issuing a commit. sql/mdl.cc: Style changes (WL#4284). sql/mysql_priv.h: Rename parameter to match the name used in the definition (WL#4284). sql/rpl_injector.cc: Release metadata locks on commit (WL#4284). sql/rpl_rli.cc: Remove assert made meaningless, metadata locks are released at the end of the transaction. sql/set_var.cc: Close tables and release locks if autocommit mode is set. sql/slave.cc: Release metadata locks after a rollback. sql/sql_acl.cc: Don't implicitly unlock locked tables. Issue a implicit commit at the end and unlock tables. sql/sql_base.cc: Defer the release of metadata locks when closing tables if not required to. Issue a deadlock error if the locking protocol requires that a transaction re-acquire its locks. Release metadata locks when closing tables for reopen. sql/sql_class.cc: Release metadata locks if the thread is killed. sql/sql_parse.cc: Release metadata locks after implicitly committing a active transaction, or after explicit commits or rollbacks. sql/sql_plugin.cc: Allocate MDL request on the stack as the use of the table is contained within the function. It will be removed from the context once close_thread_tables is called at the end of the function. sql/sql_prepare.cc: The problem is that the prepare phase of the CREATE TABLE statement takes a exclusive metadata lock lock and this can cause a self-deadlock the thread already holds a shared lock on the table being that should be created. The solution is to make the prepare phase take a shared metadata lock when preparing a CREATE TABLE statement. The execution of the statement will still acquire a exclusive lock, but won't cause any problem as it issues a implicit commit. After some discussions with stakeholders it has been decided that metadata locks acquired during a PREPARE statement must be released once the statement is prepared even if it is prepared within a multi statement transaction. sql/sql_servers.cc: Don't implicitly unlock locked tables. Issue a implicit commit at the end and unlock tables. sql/sql_table.cc: Close table and release metadata locks after a admin operation. sql/table.h: The problem is that the prepare phase of the CREATE TABLE statement takes a exclusive metadata lock lock and this can cause a self-deadlock the thread already holds a shared lock on the table being that should be created. The solution is to make the prepare phase take a shared metadata lock when preparing a CREATE TABLE statement. The execution of the statement will still acquire a exclusive lock, but won't cause any problem as it issues a implicit commit. sql/transaction.cc: Release metadata locks after the implicitly committed due to a new transaction being started. Also, release metadata locks acquired after a savepoint if the transaction is rolled back to the save point. The problem is that in some cases transaction-long metadata locks could be released before the transaction was committed. This could happen when a active transaction was ended by a "START TRANSACTION" or "BEGIN" statement, in which case the metadata locks would be released before the actual commit of the active transaction. The solution is to defer the release of metadata locks to after the transaction has been implicitly committed. No test case is provided as the effort to provide one is too disproportional to the size of the fix.	2009-12-05 02:02:48 +03:00
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.	2009-12-04 02:52:05 +03:00
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.	2009-12-04 02:29:40 +03:00
Konstantin Osipov	c52d4830bf	Backport of: ... ------------------------------------------------------------ revno: 2630.22.3 committer: Davi Arnaut <Davi.Arnaut@Sun.COM> branch nick: 4284-6.0 timestamp: Thu 2008-08-07 22:33:43 -0300 message: WL#4284: Transactional DDL locking Make transaction management more modular through a new interface. The overall objective of this change is to provide groundwork for the design of transactional DDL locking by cleaning up the transaction high level API to better distinguish operations implicit and explicit, and single statement transaction from operations on the normal transaction. Having a a high-level interface for transaction management provides a better base for implementing transactional concepts that are not always tied to storage engines and also makes it easier to interect with other higher level modules of the server. client/Makefile.am: Add new file to the build. libmysqld/CMakeLists.txt: Add new file to the build. libmysqld/Makefile.am: Add new file to the build. sql/CMakeLists.txt: Add new file to the build. sql/Makefile.am: Add new file to the build. sql/handler.cc: Remove multiplexer commit or rollback function. Most callers already have enough information to decided whether to rollback or commit. Having plain and well named functions makes it easier to read and understand code. sql/handler.h: Remove wrapper function as the low level transaction functions shouldn't be called directly anymore. sql/log_event.cc: Rename transaction management functions to the new names. sql/log_event_old.cc: Rename transaction management functions to the new names. sql/mysql_priv.h: Remove obsolete functions for implicit and explicit commit. sql/rpl_injector.cc: Rename transaction management functions to the new names. sql/rpl_rli.cc: Rename transaction management functions to the new names. sql/set_var.cc: Rename transaction management functions to the new names. sql/slave.cc: Rename transaction management functions to the new names. sql/sql_base.cc: Rename transaction management functions to the new names. sql/sql_class.cc: Rename transaction management functions to the new names. sql/sql_delete.cc: Rename transaction management functions to the new names. sql/sql_do.cc: Rename transaction management functions to the new names. sql/sql_insert.cc: Rename transaction management functions to the new names. sql/sql_parse.cc: Rename transaction management functions to the new names. sql/sql_partition.cc: Rename transaction management functions to the new names. sql/sql_table.cc: Rename transaction management functions to the new names. sql/transaction.cc: Implement wrapper functions to differentiate operations on the single statement transaction from the ones operating on the normal transaction. sql/transaction.h: Export new functions for dealing with transaction commands.	2009-12-03 21:37:38 +03:00
Konstantin Osipov	c659143c1e	Merge next-mr -> next-4284	2009-12-03 14:37:42 +03:00
Konstantin Osipov	7f628ac2dd	Backport of: ... ---------------------------------------------------------- revno: 2630.4.38 committer: Konstantin Osipov <konstantin@mysql.com> branch nick: mysql-6.0-4144 timestamp: Wed 2008-06-25 22:07:06 +0400 message: WL#4144 - Lock MERGE engine children. Committing a version of the patch merged with WL#3726 on behalf of Ingo. Step #1: Move locking from parent to children. MERGE children are now left in the query list of tables after inserted there in open_tables(). So they are locked by lock_tables() as all other tables are. The MERGE parent does not store locks any more. It appears in a MYSQL_LOCK with zero lock data. This is kind of a "dummy" lock. All other lock handling is also done directly on the children. To protect against parent or child modifications during LOCK TABLES, the children are detached after every statement and attached before every statement, even under LOCK TABLES. The children table list is removed from the query list of tables on every detach and on close of the parent. Step #2: Move MERGE specific functionality from SQL layer into table handler. Functionality moved from SQL layer (mainly sql_base.cc) to the table handler (ha_myisammrg.cc). Unnecessary code is removed from the SQL layer. Step #3: Moved all MERGE specific members from TABLE to ha_myisammrg. Moved members from TABLE to ha_myisammrg. Renamed some mebers. Fixed comments. Step #4: Valgrind and coverage testing Valgrind did not uncover new problems. Added purecov comments. Added a new test for DATA/INDEX DIRECTORY options. Changed handling of ::reset() for non-attached children. Fixed the merge-big test. Step #5: Fixed crashes detected during review Changed detection when to attach/detach. Added new tests. Backport also the fix for Bug#44040 "MySQL allows creating a MERGE table upon VIEWs but crashes when using it" include/my_base.h: WL#4144 - Lock MERGE engine children Added HA_EXTRA_ADD_CHILDREN_LIST and HA_EXTRA_IS_ATTACHED_CHILDREN for MERGE table support mysql-test/r/merge.result: WL#4144 - Lock MERGE engine children Fixed test result. mysql-test/t/disabled.def: Enable merge.test, which now is working again (WL#4144). mysql-test/t/merge-big.test: Fix the messages for wait_condition (merge with WL#3726). mysql-test/t/merge.test: WL#4144 - Lock MERGE engine children Fixed one test to meet coding standards for tests (upper case keywords, engine names as in SHOW ENGINES). Fixed error codes. Added a test for DATA/INDEX DIRECTORY. mysys/thr_lock.c: WL#4144 - Lock MERGE engine children Added purecov comments. sql/ha_partition.cc: WL#4144 - Lock MERGE engine children Added MERGE specific extra operations to ha_partition::extra(). Extended comments. Changed function comment to doxygen style. Fixed nomenclature: 'parameter' -> 'operation'. sql/mysql_priv.h: WL#4144 - Lock MERGE engine children Removed declarations for removed functions. sql/sql_base.cc: WL#4144 - Lock MERGE engine children Leave the children in the query list of tables after open_tables(). Set proper back links (prev_global). Attach MERGE children before and detach them after every statement. Even under LOCK TABLES. Remove children from the query list when they are detached. Remove lock forwarding from children to parent. Moved MERGE specific functions to ha_myisammrg.cc. Added purecov comments. Backport the fix for Bug#44040 "MySQL allows creating a MERGE table upon VIEWs but crashes when using it" sql/sql_table.cc: WL#4144 - Lock MERGE engine children Changed detection of MERGE tables. sql/table.cc: WL#4144 - Lock MERGE engine children Moved is_children_attached() method from TABLE to ha_myisammrg. sql/table.h: WL#4144 - Lock MERGE engine children Moved all MERGE specific members from TABLE to ha_myisammrg. storage/myisammrg/ha_myisammrg.cc: WL#4144 - Lock MERGE engine children Set proper back links in the child list (prev_global). Added a function for removal of the child list from the query list. Remove children from the query list when the parent is closed. Make parent lock handling a dummy (zero locks). Moved MERGE specific functionality from SQL layer to here. Moved all MERGE specific members from TABLE to ha_myisammrg. Renamed children list pointers. Added initialization and free for the children list mem_root. Fixed comments. Added purecov comments. storage/myisammrg/ha_myisammrg.h: WL#4144 - Lock MERGE engine children Added method add_children_list(). Moved all MERGE specific members from TABLE to ha_myisammrg. Renamed children list pointers. Added a mem_root for the children list. storage/myisammrg/myrg_extra.c: WL#4144 - Lock MERGE engine children Changed handling of ::reset() for non-attached children.	2009-12-03 02:09:22 +03:00
Konstantin Osipov	9148af5cdb	Backport of: ... ---------------------------------------------------------- revno: 2630.4.36 committer: Konstantin Osipov <konstantin@mysql.com> branch nick: mysql-6.0-3726 timestamp: Wed 2008-06-25 17:03:37 +0400 message: As per discussion with Serg and Dmitri, remove the code that is trying to emulate LOCK TABLES when locking tables for prelocking. This code was worked around by the engines, and has no effect. We may still have to do something to ensure that statement-based replication is consistent in MVCC engines, or other engines that downgrade table level locks, but this will have to be done somehow differently. sql/sql_base.cc: Do not try to emulate LOCK TABLES when locking tables for pre-locking.	2009-12-03 00:08:51 +03:00
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.	2009-12-02 19:31:57 +03:00
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.	2009-12-02 19:15:40 +03:00
Alexander Nozdrin	988b25cee1	Manual merge from mysql-next-mr. ... Conflicts: - sql/sql_yacc.yy	2009-12-02 18:50:14 +03:00
Konstantin Osipov	b7e8b01644	Backport of: ... ---------------------------------------------------------- revno: 2630.4.31 committer: Konstantin Osipov <konstantin@mysql.com> branch nick: mysql-6.0-3726 timestamp: Thu 2008-06-12 06:23:08 +0400 message: Extend the signature of TABLE_LIST::init_one_table() to initialize lengths This is part of WL#3726 post-review fixes.	2009-12-02 18:37:10 +03:00
Konstantin Osipov	7585067a47	Backport of: ... ---------------------------------------------------------- revno: 2630.4.30 Konstantin Osipov 2008-06-11 Fix a potential cause of test failures. sql/sql_base.cc: 0 may not be equal to (char*) 0 on 64 bit pointer/32 bit int machines.	2009-12-02 18:33:51 +03:00
Konstantin Osipov	3104af49cd	Backport of: ... ---------------------------------------------------------- revno: 2630.10.1 committer: Konstantin Osipov <konstantin@mysql.com> branch nick: mysql-6.0-lock-tables-tidyup timestamp: Wed 2008-06-11 15:49:58 +0400 message: WL#3726, review fixes. Now that we have metadata locks, we don't need to keep a crippled TABLE instance in the table cache to indicate that a table is locked. Remove all code that used this technique. Instead, rely on metadata locks and use the standard open_table() and close_thread_table() to manipulate with the table cache tables. Removes a list of functions that have become unused (see the comment for sql_base.cc for details). Under LOCK TABLES, keep a TABLE_LIST instance for each table that may be temporarily closed. For that, implement an own class for LOCK TABLES mode, Locked_tables_list. This is a pre-requisite patch for WL#4144. This is not exactly a backport: there is no new online ALTER table in Celosia, so the old alter table code was changed to work with the new table cache API. mysql-test/r/lock.result: Update results (WL#3726 post-review patch). mysql-test/r/trigger-compat.result: We take the table from the table cache now, thus no warning. mysql-test/suite/rpl/r/rpl_trigger.result: We take the table from the table cache now, thus no warning. mysql-test/t/lock.test: Additional tests for LOCK TABLES mode (previously not covered by the test suite (WL#3726). sql/field.h: Remove reopen_table(). sql/lock.cc: Remove an obsolete parameter of mysql_lock_remove(). It's not used anywhere now either. sql/mysql_priv.h: Add 4 new open_table() flags. Remove declarations of removed functions. sql/sp_head.cc: Rename thd->mdl_el_root to thd->locked_tables_root. sql/sql_acl.cc: Use the new implementation of unlock_locked_tables(). sql/sql_base.cc: Implement class Locked_tables_list. Implement close_all_tables_for_name(). Rewrite close_cached_tables() to use the new reopen_tables(). Remove reopen_table(), reopen_tables(), reopen_table_entry() (ex. open_unireg_entry()), close_data_files_and_leave_as_placeholders(), close_handle_and_leave_table_as_placeholder(), close_cached_table(), table_def_change_share(), reattach_merge(), reopen_name_locked_table(), unlink_open_table(). Move acquisition of a metadata lock into an own function - open_table_get_mdl_lock(). sql/sql_class.cc: Deploy class Locked_tables_list. sql/sql_class.h: Declare class Locked_tables_list. Keep one instance of this class in class THD. Rename mdl_el_root to locked_tables_root. sql/sql_db.cc: Update a comment. sql/sql_insert.cc: Use the plain open_table() to open a just created table in CREATE TABLE .. SELECT. sql/sql_parse.cc: Use thd->locked_tables_list to enter and leave LTM_LOCK_TABLES mode. sql/sql_partition.cc: Deploy the new method of working with partitioned table locks. sql/sql_servers.cc: Update to the new signature of unlock_locked_tables(). sql/sql_table.cc: In mysql_rm_table_part2(), the branch that removes a table under LOCK TABLES, make sure that the table being dropped is also removed from THD::locked_tables_list. Update ALTER TABLE and CREATE TABLE LIKE implementation to use open_table() and close_all_tables_for_name() instead of reopen_tables(). sql/sql_trigger.cc: Use the new locking way. sql/table.h: Add TABLE::pos_in_locked_tables, which is used only under LOCK TABLES.	2009-12-02 18:22:15 +03:00
Konstantin Osipov	e8a9191e64	Backport of: ... ------------------------------------------------------------ revno: 2630.9.3 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w3 timestamp: Wed 2008-06-11 08:33:36 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. Changed close_cached_tables() not to flush all unused TABLE instances when flushing individual table. Renamed expel_table_from_cache() to tdc_remove_table() and added enum parameter to be able more explicitly specify type of removal, rewrote its code to be more efficient. ****** Backport of: ------------------------------------------------------------ revno: 2630.9.4 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w3 timestamp: Wed 2008-06-11 15:53:53 +0400 message: WL#3726 "DDL locking for all metadata objects". After-review fixes in progress. Minor changes in order to improve code readability and simplify debugging. mysql-test/r/ps_ddl.result: Restore the original (correct) behaviour, now that the patch that fixes the regression introduced by the original patch for WL#3726 is fixed. mysql-test/t/ps_ddl.test: Restore the original (correct) behaviour, now that the patch that fixes the regression introduced by the original patch for WL#3726 is fixed sql/mysql_priv.h: Renamed expel_table_from_cache() to tdc_remove_table() and added enum parameter to be able more explicitly specify type of removal. sql/sql_base.cc: Changed close_cached_tables() not to flush all unused TABLE instances when flushing individual table. Renamed expel_table_from_cache() to tdc_remove_table() and added enum parameter to be able more explicitly specify type of removal, rewrote its code to be more efficient. As result removed relink_unused() function which is no longer used. ****** Improved code in close_cached_tables() according to reviewer's comments. sql/sql_delete.cc: Renamed expel_table_from_cache() to tdc_remove_table() and added enum parameter to be able more explicitly specify type of removal. sql/sql_rename.cc: Renamed expel_table_from_cache() to tdc_remove_table() and added enum parameter to be able more explicitly specify type of removal. sql/sql_show.cc: Moved acquisition of high-prio shared metadata lock in which happens in fill_schema_table_from_frm() to separate function. sql/sql_table.cc: Renamed expel_table_from_cache() to tdc_remove_table() and added enum parameter to be able more explicitly specify type of removal. sql/sql_trigger.cc: Renamed expel_table_from_cache() to tdc_remove_table() and added enum parameter to be able more explicitly specify type of removal.	2009-12-01 22:13:01 +03:00
Andrei Elkin	0eda48463c	Manual resolving for the following files ... Text conflict in mysql-test/collections/default.experimental Text conflict in mysql-test/r/show_check.result Text conflict in mysql-test/r/sp-code.result Text conflict in mysql-test/suite/binlog/r/binlog_tmp_table.result Text conflict in mysql-test/suite/rpl/t/disabled.def Text conflict in mysql-test/t/show_check.test Text conflict in mysys/my_delete.c Text conflict in sql/item.h Text conflict in sql/item_cmpfunc.h Text conflict in sql/log.cc Text conflict in sql/mysqld.cc Text conflict in sql/repl_failsafe.cc Text conflict in sql/slave.cc Text conflict in sql/sql_parse.cc Text conflict in sql/sql_table.cc Text conflict in sql/sql_yacc.yy Text conflict in storage/myisam/ha_myisam.cc Corrected results for stm_auto_increment_bug33029.reject 2009-12-01 20:01:49.000000000 +0300 <andrei> @@ -42,9 +42,6 @@ <andrei> RETURN i; <andrei> END// <andrei> CALL p1(); <andrei> -Warnings: <andrei> -Note 1592 Statement may not be safe to log in statement format. <andrei> -Note 1592 Statement may not be safe to log in statement format. There should be indeed no Note present because there is in fact autoincrement top-level query in sp() that triggers inserting in yet another auto-inc table. (todo: alert DaoGang to improve the test).	2009-12-01 21:07:18 +02:00
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.	2009-12-01 18:20:43 +03:00
Konstantin Osipov	db3f97c3fb	Backport of: ... ------------------------------------------------------------ revno: 2630.9.1 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w3 timestamp: Sun 2008-06-08 22:13:58 +0400 message: WL#3726 "DDL locking for all metadata objects" After review fixes in progress. Some adjustments to the patch that removes thd->locked_tables sql/sp_head.cc: Fix conditions which were wrongly translated by previous patch. sql/sql_base.cc: close_thread_tables(): Add comment clarifying control flow in case of LTM_LOCK_TABLES mode and statements requiring prelocking. Be consistent with other places where we clear OPTION_TABLE_LOCK flag. lock_tables(): Always set THD::lock to 0 after freeing memory to which it points.	2009-12-01 18:04:32 +03:00
Konstantin Osipov	466ee7e540	Backport of: ... ------------------------------------------------------------ revno: 2630.4.27 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Mon 2008-06-09 14:01:19 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. Changed open_table() to return bool. This allows more easily to distinguish cases when this function succeeds but returns no TABLE instance (in case of view or in case of special kind of open) from cases when we have an error. Pointer to TABLE instance is now always returned in TABLE_LIST::table member. This change allows to get rid of false assumption in open_tables() implementation and makes it more clear.	2009-12-01 17:58:31 +03:00
Konstantin Osipov	5969dcda21	Backport of: ... ---------------------------------------------------------- revno: 2630.4.26 committer: Konstantin Osipov <konstantin@mysql.com> branch nick: mysql-6.0-prelocked_mode-to-push timestamp: Fri 2008-06-06 23:19:04 +0400 message: WL#3726: work on review comments. Remove thd->locked_tables. Always store MYSQL_LOCK instances in thd->lock. Rename thd->prelocked_mode to thd->locked_tables_mode. Use thd->locked_tables_mode to determine if we are under LOCK TABLES. Update the code to not assume that if thd->lock is set, LOCK TABLES mode is off. Review comments. sql/ha_ndbcluster_binlog.cc: Don't unlock the lock under LOCK TABLES (safety). sql/handler.cc: There is no thd->locked_tables any more. Update comments. sql/lock.cc: There is no thd->locked_tables any more. sql/log.cc: Rename thd->prelocked_mode to thd->locked_tables_mode. sql/set_var.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sp_head.cc: Rename thd->prelocked_mode to thd->locked_tables_mode. sql/sql_base.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. Remove thd->locked_tables. sql/sql_cache.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_class.cc: Avoid code duplication. Do not release the table locks prematurely if we're under LOCK TABLES. Use thd->locked_tables_mode instead of thd->locked_tables. sql/sql_class.h: Remove thd->locked_tables. Make prelocked mode a kind of LOCK TABLES mode. Update comments. sql/sql_cursor.cc: Update comments. sql/sql_insert.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. Rename thd->prelocked_mode to thd->locked_tables_mode. sql/sql_load.cc: Rename thd->prelocked_mode to thd->locked_tables_mode. sql/sql_parse.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. Remove thd->locked_tables. sql/sql_partition.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_rename.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_select.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_table.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_trigger.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_update.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_view.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. storage/myisam/ha_myisam.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES.	2009-12-01 17:39:03 +03:00
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.	2009-12-01 16:59:11 +03:00
Konstantin Osipov	1480dafe2f	Backport of: ... ------------------------------------------------------------ revno: 2630.8.3 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w4 timestamp: Thu 2008-06-05 10:48:36 +0400 message: WL#3726 "DDL locking for all metadata objects". After-review fixes in progress. Adjust some comments that were using old terminology (name locks instead of exclusive metadata locks), brought some of them up-to-date with current situation in code. sql/sql_base.cc: Adjusted comments to use proper terminology. sql/sql_delete.cc: Adjusted comments to use proper terminology. sql/sql_handler.cc: Adjusted comments to use proper terminology. sql/sql_partition.cc: Adjusted comments to use proper terminology also fixed one comment to correspond to what really happens in code. sql/sql_show.cc: Adjusted comments to use proper terminology. sql/sql_table.cc: Adjusted comments to use proper terminology, brought one of them up-to-date with current situation. sql/sql_trigger.cc: Adjusted comments to use proper terminology. sql/table.h: Removed two unused members of TABLE_SHARE struct.	2009-12-01 16:51:50 +03:00
Konstantin Osipov	93b55a006d	Backport of: ... ------------------------------------------------------------ revno: 2630.4.20 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Wed 2008-06-04 16:27:06 +0400 message: 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. 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.	2009-12-01 16:38:00 +03:00
Konstantin Osipov	1ed585adff	Backport of: ... --------------------------------------------- 2630.7.3 Konstantin Osipov 2008-06-02 Various style changes preceding the removal of reopen_table(). (Post-review fixes for WL#3726). sql/event_db_repository.cc: Update to use the new signature of TABLE_LIST::init_one_table(). sql/mysql_priv.h: Move close_cached_table() and wait_while_table_is_used() to sql_base.cc. sql/sql_base.cc: Move close_cached_table() and wait_while_table_is_used() from sql_table.cc. sql/sql_table.cc: Move close_cached_table() and wait_while_table_is_used() to sql_base.cc. sql/table.h: Update the signature of TABLE_LIST::init_one_table().	2009-12-01 16:27:03 +03:00
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.	2009-12-01 01:39:13 +03:00
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).	2009-12-01 01:33:22 +03:00
Konstantin Osipov	cf45b61a6a	Backport of: ... ------------------------------------------------------------ revno: 2630.4.16 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w timestamp: Thu 2008-05-29 09:45:02 +0400 message: WL#3726 "DDL locking for all metadata objects". After review changes in progress. Tweaked some comments and did some renames to avoid ambiguites. sql/mysql_priv.h: Removed name_lock_locked_table() function. sql/sql_base.cc: Got rid of name_lock_locked_table() function after replacing the only call to it with its body. Simplified open_table() code by making "action" argument mandatory (i.e. one now should always pass non-0 pointer in this argument). Renamed TABLE_LIST::open_table_type to open_type to avoid confusing it with type of table. Adjusted comments according to review. sql/sql_handler.cc: Added comment clarifying in which cases we can have TABLE::mdl_lock set to 0. sql/sql_insert.cc: Now the 4th argument of open_table() is mandatory (it makes no sense to complicate open_table() code when we can simply pass dummy variable). sql/sql_parse.cc: Renamed TABLE_LIST::open_table_type to open_type to avoid confusing it with type of table. sql/sql_prepare.cc: Renamed TABLE_LIST::open_table_type to open_type to avoid confusing it with type of table. sql/sql_table.cc: Now the 4th argument of open_table() is mandatory (it makes no sense to complicate open_table() code when we can simply pass dummy variable). sql/sql_trigger.cc: Replaced the only call to name_lock_locked_table() function with its body. sql/sql_view.cc: Renamed TABLE_LIST::open_table_type to open_type to avoid confusing it with type of table. sql/table.h: Renamed TABLE_LIST::open_table_type to open_type (to avoid confusing it with type of table) and improved comments describing this member.	2009-12-01 01:13:06 +03:00