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301 commits

Author SHA1 Message Date
Konstantin Osipov
29c4873ad5 Commit on behalf of Dmitry Lenev.
Merge his patch for Bug#52044 into 5.5, and apply 
review comments.
2010-08-12 17:50:23 +04:00
Konstantin Osipov
523066987d A fix for Bug#41158 "DROP TABLE holds LOCK_open during unlink()".
Remove acquisition of LOCK_open around file system operations,
since such operations are now protected by metadata locks.
Rework table discovery algorithm to not require LOCK_open.

No new tests added since all MDL locking operations are covered
in lock.test and mdl_sync.test, and as long as these tests
pass despite the increased concurrency, consistency must be
unaffected.

mysql-test/t/disabled.def:
  Disable NDB tests due to Bug#55799.
sql/datadict.cc:
  No longer necessary to protect ha_create_table() with
  LOCK_open. Serial execution is now ensured by metadata
  locks.
sql/ha_ndbcluster.cc:
  Do not manipulate with LOCK_open in cluster code.
sql/ha_ndbcluster_binlog.cc:
  Do not manipulate with LOCK_open in cluster code.
sql/ha_ndbcluster_binlog.h:
  Update function signature.
sql/handler.cc:
  Implement ha_check_if_table_exists().
  @todo: some engines provide ha_table_exists_in_engine()
  handlerton call, for those we perhaps shouldn't
  call ha_discover(), to be more efficient.
  Since currently it's only NDB, postpone till
  integration with NDB.
sql/handler.h:
  Declare ha_check_if_table_exists() function.
sql/mdl.cc:
  Remove an obsolete comment.
sql/sql_base.cc:
  Update to a new signature of close_cached_tables():
  from now on we always call it without LOCK_open.
  Update comments.
  Remove get_table_share_with_create(), we should
  not attempt to create a table under LOCK_open.
  Introduce get_table_share_with_discover() instead,
  which would request a back off action if the table
  exists in engine.
  Remove acquisition of LOCK_open for 
  data dictionary operations, such as check_if_table_exists().
  Do not use get_table_share_with_create/discover for views,
  where it's not needed.
  Make tdc_remove_table() optionally acquire LOCK_open
  to simplify usage of this function.
  Use the right mutex in the partitioning code when
  manipulating with thd->open_tables.
sql/sql_base.h:
  Update signatures of changes functions.
sql/sql_insert.cc:
  Do not wrap quick_rm_table() with LOCK_open acquisition, 
  this is unnecessary.
sql/sql_parse.cc:
  Update to the new calling convention of tdc_remove_table().
  Update to the new signature of close_cached_tables().
  Update comments.
sql/sql_rename.cc:
  Update to the new calling convention of tdc_remove_table().
  Remove acquisition of LOCK_open around filesystem
  operations.
sql/sql_show.cc:
  Remove get_trigger_table_impl().
  Do not acquire LOCK_open for a dirty read of the trigger
  file.
sql/sql_table.cc:
  Do not acquire LOCK_open for filesystem operations.
sql/sql_trigger.cc:
  Do not require LOCK_open for trigger file I/O.
sql/sql_truncate.cc:
  Update to the new signature of tdc_remove_table().
sql/sql_view.cc:
  Do not require LOCK_open for view I/O.
  Use tdc_remove_table() to expel view share.
  Update comments.
sql/sys_vars.cc:
  Update to the new signature of close_cached_tables().
2010-08-09 22:33:47 +04:00
Konstantin Osipov
5861d8e768 Fix a compilation failure of ha_ndbcluster_binlog.cc.
sql/ha_ndbcluster_binlog.cc:
  Fix a compilation failure when built with 
  autotools.
2010-07-29 20:15:37 +04:00
Dmitry Lenev
00496b7acd Fix for bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH
TABLES <list> WITH READ LOCK are incompatible".

The problem was that FLUSH TABLES <list> WITH READ LOCK
which was issued when other connection has acquired global
read lock using FLUSH TABLES WITH READ LOCK was blocked
and has to wait until global read lock is released.

This issue stemmed from the fact that FLUSH TABLES <list>
WITH READ LOCK implementation has acquired X metadata locks
on tables to be flushed. Since these locks required acquiring
of global IX lock this statement was incompatible with global
read lock.

This patch addresses problem by using SNW metadata type of
lock for tables to be flushed by FLUSH TABLES <list> WITH
READ LOCK. It is OK to acquire them without global IX lock
as long as we won't try to upgrade those locks. Since SNW
locks allow concurrent statements using same table FLUSH
TABLE <list> WITH READ LOCK now has to wait until old
versions of tables to be flushed go away after acquiring
metadata locks. Since such waiting can lead to deadlock
MDL deadlock detector was extended to take into account
waits for flush and resolve such deadlocks.

As a bonus code in open_tables() which was responsible for
waiting old versions of tables to go away was refactored.
Now when we encounter old version of table in open_table()
we don't back-off and wait for all old version to go away,
but instead wait for this particular table to be flushed.
Such approach supported by deadlock detection should reduce
number of scenarios in which FLUSH TABLES aborts concurrent
multi-statement transactions.

Note that active FLUSH TABLES <list> WITH READ LOCK still
blocks concurrent FLUSH TABLES WITH READ LOCK statement
as the former keeps tables open and thus prevents the
latter statement from doing flush.

mysql-test/include/handler.inc:
  Adjusted test case after changing status which is set
  when FLUSH TABLES waits for tables to be flushed from
  "Flushing tables" to "Waiting for table".
mysql-test/r/flush.result:
  Added test which checks that "flush tables <list> with
  read lock" is compatible with active "flush tables with
  read lock" but not vice-versa. This test also covers
  bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH TABLES
  <list> WITH READ LOCK are incompatible".
mysql-test/r/mdl_sync.result:
  Added scenarios in which wait for table to be flushed
  causes deadlocks to the coverage of MDL deadlock detector.
mysql-test/suite/perfschema/r/dml_setup_instruments.result:
  Adjusted test results after removal of COND_refresh
  condition variable.
mysql-test/suite/perfschema/r/server_init.result:
  Adjusted test and its results after removal of COND_refresh
  condition variable.
mysql-test/suite/perfschema/t/server_init.test:
  Adjusted test and its results after removal of COND_refresh
  condition variable.
mysql-test/t/flush.test:
  Added test which checks that "flush tables <list> with
  read lock" is compatible with active "flush tables with
  read lock" but not vice-versa. This test also covers
  bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH TABLES
  <list> WITH READ LOCK are incompatible".
mysql-test/t/kill.test:
  Adjusted test case after changing status which is set
  when FLUSH TABLES waits for tables to be flushed from
  "Flushing tables" to "Waiting for table".
mysql-test/t/lock_multi.test:
  Adjusted test case after changing status which is set
  when FLUSH TABLES waits for tables to be flushed from
  "Flushing tables" to "Waiting for table".
mysql-test/t/mdl_sync.test:
  Added scenarios in which wait for table to be flushed
  causes deadlocks to the coverage of MDL deadlock detector.
sql/ha_ndbcluster.cc:
  Adjusted code after adding one more parameter for
  close_cached_tables() call - timeout for waiting for
  table to be flushed.
sql/ha_ndbcluster_binlog.cc:
  Adjusted code after adding one more parameter for
  close_cached_tables() call - timeout for waiting for
  table to be flushed.
sql/lock.cc:
  Removed COND_refresh condition variable. See comment
  for sql_base.cc for details.
sql/mdl.cc:
  Now MDL deadlock detector takes into account information
  about waits for table flushes when searching for deadlock.
  To implement this change:
  - Declaration of enum_deadlock_weight and
    Deadlock_detection_visitor were moved to mdl.h header
    to make them available to the code in table.cc which
    implements deadlock detector traversal through edges
    of waiters graph representing waiting for flush.
  - Since now MDL_context may wait not only for metadata
    lock but also for table to be flushed an abstract
    Wait_for_edge class was introduced. Its descendants
    MDL_ticket and Flush_ticket incapsulate specifics
    of inspecting waiters graph when following through
    edge representing wait of particular type.
  
  We no longer require global IX metadata lock when acquiring
  SNW or SNRW locks. Such locks are needed only when metadata
  locks of these types are upgraded to X locks. This allows
  to use SNW locks in FLUSH TABLES <list> WITH READ LOCK
  implementation and keep the latter compatible with global
  read lock.
sql/mdl.h:
  Now MDL deadlock detector takes into account information
  about waits for table flushes when searching for deadlock.
  To implement this change:
  - Declaration of enum_deadlock_weight and
    Deadlock_detection_visitor were moved to mdl.h header
    to make them available to the code in table.cc which
    implements deadlock detector traversal through edges
    of waiters graph representing waiting for flush.
  - Since now MDL_context may wait not only for metadata
    lock but also for table to be flushed an abstract
    Wait_for_edge class was introduced. Its descendants
    MDL_ticket and Flush_ticket incapsulate specifics
    of inspecting waiters graph when following through
    edge representing wait of particular type.
  - Deadlock_detection_visitor now has m_table_shares_visited
    member which allows to support recursive locking for
    LOCK_open. This is required when deadlock detector
    inspects waiters graph which contains several edges
    representing waits for flushes or needs to come through
    the such edge more than once.
sql/mysqld.cc:
  Removed COND_refresh condition variable. See comment
  for sql_base.cc for details.
sql/mysqld.h:
  Removed COND_refresh condition variable. See comment
  for sql_base.cc for details.
sql/sql_base.cc:
  Changed approach to how threads are waiting for table
  to be flushed. Now thread that wants to wait for old
  table to go away subscribes for notification by adding
  Flush_ticket to table's share and waits using
  MDL_context::m_wait object. Once table gets flushed
  (i.e. all tables are closed and table share is ready
  to be destroyed) all such waiters are notified
  individually.
  Thanks to this change MDL deadlock detector can take
  such waits into account.
  
  To implement this/as result of this change:
  - tdc_wait_for_old_versions() was replaced with
    tdc_wait_for_old_version() which waits for individual
    old share to go away and which is called by open_table()
    after finding out that share is outdated. We don't
    need to perform back-off before such waiting thanks
    to the fact that deadlock detector now sees such waits.
  - As result Open_table_ctx::m_mdl_requests became
    unnecessary and was removed. We no longer allocate
    copies of MDL_request objects on MEM_ROOT when
    MYSQL_OPEN_FORCE_SHARED/SHARED_HIGH_PRIO flags are
    in effect.
  - close_cached_tables() and tdc_wait_for_old_version()
    share code which implements waiting for share to be
    flushed - the both use TABLE_SHARE::wait_until_flush()
    method. Thanks to this close_cached_tables() supports
    timeouts and has extra parameter for this.
  - Open_table_context::OT_MDL_CONFLICT enum element was
    renamed to OT_CONFLICT as it is now also used in cases
    when back-off is required to resolve deadlock caused
    by waiting for flush and not metadata lock.
  - In cases when we discover that current connection tries
    to open tables from different generation we now simply
    back-off and restart process of opening tables. To
    support this Open_table_context::OT_REOPEN_TABLES enum
    element was added.
  - COND_refresh condition variable became unnecessary and
    was removed.
  - mysql_notify_thread_having_shared_lock() no longer wakes
    up connections waiting for flush as all such connections
    can be waken up by deadlock detector if necessary.
sql/sql_base.h:
  - close_cached_tables() now has one more parameter -
    timeout for waiting for table to be flushed.
  - Open_table_context::OT_MDL_CONFLICT enum element was
    renamed to OT_CONFLICT as it is now also used in cases
    when back-off is required to resolve deadlock caused
    by waiting for flush and not metadata lock.
    Added new OT_REOPEN_TABLES enum element to be used in
    cases when we need to restart open tables process even
    in the middle of transaction.
  - Open_table_ctx::m_mdl_requests became unnecessary and
    was removed.
sql/sql_class.h:
  Added assert ensuring that we won't use LOCK_open mutex
  with THD::enter_cond(). Otherwise deadlocks can arise in
  MDL deadlock detector.
sql/sql_parse.cc:
  Changed FLUSH TABLES <list> WITH READ LOCK to take SNW
  metadata locks instead of X locks on tables to be flushed.
  Since we no longer require global IX lock to be taken
  when SNW locks are taken this makes this statement
  compatible with FLUSH TABLES WITH READ LOCK statement.
  Since SNW locks allow other connections to have table
  opened FLUSH TABLES <list> WITH READ LOCK now has to
  wait during open_tables() for old version to go away.
  Such waits can lead to deadlocks which will be detected
  by MDL deadlock detector which now takes waits for table
  to be flushed into account.
  
  Also adjusted code after adding one more parameter for
  close_cached_tables() call - timeout for waiting for
  table to be flushed.
sql/sql_yacc.yy:
  FLUSH TABLES <list> WITH READ LOCK now needs only SNW
  metadata locks on tables.
sql/sys_vars.cc:
  Adjusted code after adding one more parameter for
  close_cached_tables() call - timeout for waiting for
  table to be flushed.
sql/table.cc:
  Implemented new approach to how threads are waiting for
  table to be flushed. Now thread that wants to wait for
  old table to go away subscribes for notification by
  adding Flush_ticket to table's share and waits using
  MDL_context::m_wait object. Once table gets flushed
  (i.e. all tables are closed and table share is ready
  to be destroyed) all such waiters are notified
  individually. This change allows to make such waits
  visible inside of MDL deadlock detector.
  To do it:
  
  - Added list of waiters/Flush_tickets to TABLE_SHARE
    class.
  - Changed free_table_share() to postpone freeing of
    share memory until last waiter goes away and to
    wake up subscribed waiters.
  - Added TABLE_SHARE::wait_until_flushed() method which
    implements subscription to the list of waiters for
    table to be flushed and waiting for this event.
  
  Implemented interface which allows to expose waits for
  flushes to MDL deadlock detector:
  
  - Introduced Flush_ticket class a descendant of
    Wait_for_edge class.
  - Added TABLE_SHARE::find_deadlock() method which allows
    deadlock detector to find out what contexts are still
    using old version of table in question (i.e. to find
    out what contexts are waited for by owner of
    Flush_ticket).
sql/table.h:
  In order to support new strategy of waiting for table flush
  (see comment for table.cc for details) added list of
  waiters/Flush_tickets to TABLE_SHARE class.
  
  Implemented interface which allows to expose waits for
  flushes to MDL deadlock detector:
  - Introduced Flush_ticket class a descendant of
    Wait_for_edge class.
  - Added TABLE_SHARE::find_deadlock() method which allows
    deadlock detector to find out what contexts are still
    using old version of table in question (i.e. to find
    out what contexts are waited for by owner of
    Flush_ticket).
2010-07-27 17:34:58 +04:00
Konstantin Osipov
36290c0923 A pre-requisite patch for the fix for Bug#52044.
This patch also fixes Bug#55452 "SET PASSWORD is
replicated twice in RBR mode".

The goal of this patch is to remove the release of 
metadata locks from close_thread_tables().
This is necessary to not mistakenly release
the locks in the course of a multi-step
operation that involves multiple close_thread_tables()
or close_tables_for_reopen().

On the same token, move statement commit outside 
close_thread_tables().

Other cleanups:
Cleanup COM_FIELD_LIST.
Don't call close_thread_tables() in COM_SHUTDOWN -- there
are no open tables there that can be closed (we leave
the locked tables mode in THD destructor, and this
close_thread_tables() won't leave it anyway).

Make open_and_lock_tables() and open_and_lock_tables_derived()
call close_thread_tables() upon failure.
Remove the calls to close_thread_tables() that are now
unnecessary.

Simplify the back off condition in Open_table_context.

Streamline metadata lock handling in LOCK TABLES 
implementation.

Add asserts to ensure correct life cycle of 
statement transaction in a session.

Remove a piece of dead code that has also become redundant
after the fix for Bug 37521.

mysql-test/r/variables.result:
  Update results: set @@autocommit and statement transaction/
  prelocked mode.
mysql-test/r/view.result:
  A harmless change in CHECK TABLE <view> status for a broken view.
  If previously a failure to prelock all functions used in a view 
  would leave the connection in LTM_PRELOCKED mode, now we call
  close_thread_tables() from open_and_lock_tables()
  and leave prelocked mode, thus some check in mysql_admin_table() that
  works only in prelocked/locked tables mode is no longer activated.
mysql-test/suite/rpl/r/rpl_row_implicit_commit_binlog.result:
  Fixed Bug#55452 "SET PASSWORD is replicated twice in
  RBR mode": extra binlog events are gone from the
  binary log.
mysql-test/t/variables.test:
  Add a test case: set autocommit and statement transaction/prelocked
  mode.
sql/event_data_objects.cc:
  Simplify code in Event_job_data::execute().
  Move sp_head memory management to lex_end().
sql/event_db_repository.cc:
  Move the release of metadata locks outside
  close_thread_tables().
  Make sure we call close_thread_tables() when
  open_and_lock_tables() fails and remove extra
  code from the events data dictionary.
  Use close_mysql_tables(), a new internal
  function to properly close mysql.* tables
  in the data dictionary.
  Contract Event_db_repository::drop_events_by_field,
  drop_schema_events into one function.
  When dropping all events in a schema,
  make sure we don't mistakenly release all
  locks acquired by DROP DATABASE. These
  include locks on the database name
  and the global intention exclusive
  metadata lock.
sql/event_db_repository.h:
  Function open_event_table() does not require an instance 
  of Event_db_repository.
sql/events.cc:
  Use close_mysql_tables() instead of close_thread_tables()
  to bootstrap events, since the latter no longer
  releases metadata locks.
sql/ha_ndbcluster.cc:
  - mysql_rm_table_part2 no longer releases
  acquired metadata locks. Do it in the caller.
sql/ha_ndbcluster_binlog.cc:
  Deploy the new protocol for closing thread
  tables in run_query() and ndb_binlog_index
  code.
sql/handler.cc:
  Assert that we never call ha_commit_trans/
  ha_rollback_trans in sub-statement, which
  is now the case.
sql/handler.h:
  Add an accessor to check whether THD_TRANS object
  is empty (has no transaction started).
sql/log.cc:
  Update a comment.
sql/log_event.cc:
  Since now we commit/rollback statement transaction in 
  mysql_execute_command(), we need a mechanism to communicate
  from Query_log_event::do_apply_event() to mysql_execute_command()
  that the statement transaction should be rolled back, not committed.
  Ideally it would be a virtual method of THD. I hesitate
  to make THD a virtual base class in this already large patch.
  Use a thd->variables.option_bits for now.
  
  Remove a call to close_thread_tables() from the slave IO
  thread. It doesn't open any tables, and the protocol
  for closing thread tables is more complicated now.
  
  Make sure we properly close thread tables, however, 
  in Load_data_log_event, which doesn't
  follow the standard server execution procedure
  with mysql_execute_command().
  @todo: this piece should use Server_runnable
  framework instead.
  Remove an unnecessary call to mysql_unlock_tables().
sql/rpl_rli.cc:
  Update Relay_log_info::slave_close_thread_tables()
  to follow the new close protocol.
sql/set_var.cc:
  Remove an unused header.
sql/slave.cc:
  Remove an unnecessary call to
  close_thread_tables().
sql/sp.cc:
  Remove unnecessary calls to close_thread_tables()
  from SP DDL implementation. The tables will
  be closed by the caller, in mysql_execute_command().
  When dropping all routines in a database, make sure
  to not mistakenly drop all metadata locks acquired
  so far, they include the scoped lock on the schema.
sql/sp_head.cc:
  Correct the protocol that closes thread tables
  in an SP instruction.
  Clear lex->sphead before cleaning up lex
  with lex_end to make sure that we don't
  delete the sphead twice. It's considered
  to be "cleaner" and more in line with
  future changes than calling delete lex->sphead
  in other places that cleanup the lex.
sql/sp_head.h:
  When destroying m_lex_keeper of an instruction,
  don't delete the sphead that all lex objects
  share. 
  @todo: don't store a reference to routine's sp_head
  instance in instruction's lex.
sql/sql_acl.cc:
  Don't call close_thread_tables() where the caller will
  do that for us.
  Fix Bug#55452 "SET PASSWORD is replicated twice in RBR 
  mode" by disabling RBR replication in change_password()
  function.
  Use close_mysql_tables() in bootstrap and ACL reload
  code to make sure we release all metadata locks.
sql/sql_base.cc:
  This is the main part of the patch:
  - remove manipulation with thd->transaction
  and thd->mdl_context from close_thread_tables().
  Now this function is only responsible for closing
  tables, nothing else.
  This is necessary to be able to easily use
  close_thread_tables() in procedures, that
  involve multiple open/close tables, which all
  need to be protected continuously by metadata
  locks.
  Add asserts ensuring that TABLE object
  is only used when is protected by a metadata lock.
  Simplify the back off condition of Open_table_context,
  we no longer need to look at the autocommit mode.
  Make open_and_lock_tables() and open_normal_and_derived_tables()
  close thread tables and release metadata locks acquired so-far 
  upon failure. This simplifies their usage.
  Implement close_mysql_tables().
sql/sql_base.h:
  Add declaration for close_mysql_tables().
sql/sql_class.cc:
  Remove a piece of dead code that has also become redundant
  after the fix for Bug 37521.
  The code became dead when my_eof() was made a non-protocol method,
  but a method that merely modifies the diagnostics area.
  The code became redundant with the fix for Bug#37521, when 
  we started to cal close_thread_tables() before
  Protocol::end_statement().
sql/sql_do.cc:
  Do nothing in DO if inside a substatement
  (the assert moved out of trans_rollback_stmt).
sql/sql_handler.cc:
  Add comments.
sql/sql_insert.cc:
  Remove dead code. 
  Release metadata locks explicitly at the
  end of the delayed insert thread.
sql/sql_lex.cc:
  Add destruction of lex->sphead to lex_end(),
  lex "reset" method called at the end of each statement.
sql/sql_parse.cc:
  Move close_thread_tables() and other related
  cleanups to mysql_execute_command()
  from dispatch_command(). This has become
  possible after the fix for Bug#37521.
  Mark federated SERVER statements as DDL.
  
  Next step: make sure that we don't store
  eof packet in the query cache, and move
  the query cache code outside mysql_parse.
  
  Brush up the code of COM_FIELD_LIST.
  Remove unnecessary calls to close_thread_tables().
  
  When killing a query, don't report "OK"
  if it was a suicide.
sql/sql_parse.h:
  Remove declaration of a function that is now static.
sql/sql_partition.cc:
  Remove an unnecessary call to close_thread_tables().
sql/sql_plugin.cc:
  open_and_lock_tables() will clean up
  after itself after a failure.
  Move close_thread_tables() above
  end: label, and replace with close_mysql_tables(),
  which will also release the metadata lock
  on mysql.plugin.
sql/sql_prepare.cc:
  Now that we no longer release locks in close_thread_tables()
  statement prepare code has become more straightforward.
  Remove the now redundant check for thd->killed() (used
  only by the backup project) from Execute_server_runnable.
  Reorder code to take into account that now mysql_execute_command()
  performs lex->unit.cleanup() and close_thread_tables().
sql/sql_priv.h:
  Add a new option to server options to interact
  between the slave SQL thread and execution
  framework (hack). @todo: use a virtual
  method of class THD instead.
sql/sql_servers.cc:
  Due to Bug 25705 replication of 
  DROP/CREATE/ALTER SERVER is broken.
  Make sure at least we do not attempt to 
  replicate these statements using RBR,
  as this violates the assert in close_mysql_tables().
sql/sql_table.cc:
  Do not release metadata locks in mysql_rm_table_part2,
  this is done by the caller.
  Do not call close_thread_tables() in mysql_create_table(),
  this is done by the caller. 
  Fix a bug in DROP TABLE under LOCK TABLES when,
  upon error in wait_while_table_is_used() we would mistakenly
  release the metadata lock on a non-dropped table.
  Explicitly release metadata locks when doing an implicit
  commit.
sql/sql_trigger.cc:
  Now that we delete lex->sphead in lex_end(),
  zero the trigger's sphead in lex after loading
  the trigger, to avoid double deletion.
sql/sql_udf.cc:
  Use close_mysql_tables() instead of close_thread_tables().
sql/sys_vars.cc:
  Remove code added in scope of WL#4284 which would
  break when we perform set @@session.autocommit along
  with setting other variables and using tables or functions.
  A test case added to variables.test.
sql/transaction.cc:
  Add asserts.
sql/tztime.cc:
  Use close_mysql_tables() rather than close_thread_tables().
2010-07-27 14:25:53 +04:00
Davi Arnaut
f56dd32bf7 Bug#34043: Server loops excessively in _checkchunk() when safemalloc is enabled
Essentially, the problem is that safemalloc is excruciatingly
slow as it checks all allocated blocks for overrun at each
memory management primitive, yielding a almost exponential
slowdown for the memory management functions (malloc, realloc,
free). The overrun check basically consists of verifying some
bytes of a block for certain magic keys, which catches some
simple forms of overrun. Another minor problem is violation
of aliasing rules and that its own internal list of blocks
is prone to corruption.

Another issue with safemalloc is rather the maintenance cost
as the tool has a significant impact on the server code.
Given the magnitude of memory debuggers available nowadays,
especially those that are provided with the platform malloc
implementation, maintenance of a in-house and largely obsolete
memory debugger becomes a burden that is not worth the effort
due to its slowness and lack of support for detecting more
common forms of heap corruption.

Since there are third-party tools that can provide the same
functionality at a lower or comparable performance cost, the
solution is to simply remove safemalloc. Third-party tools
can provide the same functionality at a lower or comparable
performance cost. 

The removal of safemalloc also allows a simplification of the
malloc wrappers, removing quite a bit of kludge: redefinition
of my_malloc, my_free and the removal of the unused second
argument of my_free. Since free() always check whether the
supplied pointer is null, redudant checks are also removed.

Also, this patch adds unit testing for my_malloc and moves
my_realloc implementation into the same file as the other
memory allocation primitives.

client/mysqldump.c:
  Pass my_free directly as its signature is compatible with the
  callback type -- which wasn't the case for free_table_ent.
2010-07-08 18:20:08 -03:00
Konstantin Osipov
cc6dabba37 Merge trunk-bugfixing -> trunk-runtime 2010-06-17 17:31:51 +04:00
Alexey Kopytov
2845586723 Fixed ha_ndbcluster_binlog.cc to use Parser_state::init(). 2010-06-12 00:35:28 +04:00
Konstantin Osipov
90a87cd52d A pre-requisite for WL#5419 "LOCK_open scalability:
make tdc_refresh_version an 
atomic counter".
Backport the trivial changes from mysql-trunk-iplus.
2010-06-10 15:43:32 +04:00
Alexander Nozdrin
cc6d110e48 Follow-up patch for Bug#27863 (excessive memory usage for many small queries
in a multiquery packet): fix NDB test failures.
2010-05-17 16:10:26 +04:00
Alexander Nozdrin
6facd4cb13 Patch for Bug#27863 (excessive memory usage for many small queries in a
multiquery packet).

Background:

  - a query can contain multiple SQL statements;

  - the server frees resources allocated to process a query when the
    whole query is handled. In other words, resources allocated to process
    one SQL statement from a multi-statement query are freed when all SQL
    statements are handled.

The problem was that the parser allocated a buffer of size of the whole
query for each SQL statement in a multi-statement query. Thus, if a query
had many SQL-statements (so, the query was long), but each SQL statement
was short, ther parser tried to allocate huge amount of memory (number of
small SQL statements * length of the whole query).

The memory was allocated for a so-called "cpp buffer", which is intended to
store pre-processed SQL statement -- SQL text without version specific
comments.

The fix is to allocate memory for the "cpp buffer" once for all SQL
statements (once for a query).
2010-05-14 22:11:25 +04:00
Mats Kindahl
23d8586dbf WL#5030: Split and remove mysql_priv.h
This patch:

- Moves all definitions from the mysql_priv.h file into
  header files for the component where the variable is
  defined
- Creates header files if the component lacks one
- Eliminates all include directives from mysql_priv.h
- Eliminates all circular include cycles
- Rename time.cc to sql_time.cc
- Rename mysql_priv.h to sql_priv.h
2010-03-31 16:05:33 +02:00
Konstantin Osipov
7116431a8a A review comment for the fix for Bug#46672.
Remove unnecessary need_reopen loops.
2010-03-13 13:58:27 +03:00
Jon Olav Hauglid
e60ef89317 Followup to Bug#45225 Locking: hang if drop table with no timeout
This patch prevents system threads and system table accesses from
using user-specified values for "lock_wait_timeout". Instead all
such accesses are done using the default value (1 year).

This prevents background tasks (such as replication, events, 
accessing stored function definitions, logging, reading time-zone
information, etc.) from failing in cases where the global value
of "lock_wait_timeout" is set very low.

The patch also simplifies the open tables API. Rather than adding
another convenience function for opening and locking system tables,
this patch removes most of the existing convenience functions for
open_and_lock_tables_derived(). Before, open_and_lock_tables() was
a convenience function that enforced derived tables handling, while
open_and_lock_tables_derived() was the main function where derived
tables handling was optional. Now, this convencience function is
gone and the main function is renamed to open_and_lock_tables(). 

No test case added as it would have required the use of --sleep to
check that system threads and system tables have a different timeout
value from the user-specified "lock_wait_timeout" system variable.
2010-02-24 18:04:00 +01:00
Konstantin Osipov
e7b332ba83 Merge next-mr -> next-4284. 2010-02-05 01:08:08 +03:00
Konstantin Osipov
a9e22b5896 Merge next-mr -> next-4284-merge. 2010-02-04 20:34:15 +03:00
Konstantin Osipov
c8555bdb35 Merge next-mr -> next-4284 2010-02-03 16:43:03 +03:00
Konstantin Osipov
056ac55aa0 Merge next-mr -> next-4284. 2010-02-03 03:06:42 +03:00
Konstantin Osipov
665100b69d Merge next-mr -> next-4284. 2010-02-02 02:22:16 +03:00
Alfranio Correia
b4c0c1550c merge mysql-next-mr --> mysql-5.1-rpl-merge
Conflicts:
  Text conflict in sql/sql_insert.cc
2010-01-14 16:02:55 +00:00
Alfranio Correia
40949a3110 merge mysql-next-mr --> mysql-5.1-rpl-merge
Conflicts:
  Text conflict in sql/log.cc
  Text conflict in sql/slave.cc
  Text conflict in sql/sql_base.cc
2010-01-13 12:22:34 +00:00
unknown
16e15e6952 Manual merge from next-mr. 2010-01-12 20:07:09 +08:00
Marc Alff
e0e0f9e3d4 WL#2360 Performance schema
Part V: performance schema implementation
2010-01-11 18:47:27 -07:00
Alfranio Correia
5dcb0e447f merge mysql-5.1-rep+2-delivery1 --> mysql-5.1-rpl-merge
Conflicts:

Text conflict in .bzr-mysql/default.conf
Text conflict in mysql-test/extra/rpl_tests/rpl_loaddata.test
Text conflict in mysql-test/r/mysqlbinlog2.result
Text conflict in mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result
Text conflict in mysql-test/suite/binlog/r/binlog_unsafe.result
Text conflict in mysql-test/suite/rpl/r/rpl_insert_id.result
Text conflict in mysql-test/suite/rpl/r/rpl_loaddata.result
Text conflict in mysql-test/suite/rpl/r/rpl_stm_auto_increment_bug33029.result
Text conflict in mysql-test/suite/rpl/r/rpl_udf.result
Text conflict in mysql-test/suite/rpl/t/rpl_slow_query_log.test
Text conflict in sql/field.h
Text conflict in sql/log.cc
Text conflict in sql/log_event.cc
Text conflict in sql/log_event_old.cc
Text conflict in sql/mysql_priv.h
Text conflict in sql/share/errmsg.txt
Text conflict in sql/sp.cc
Text conflict in sql/sql_acl.cc
Text conflict in sql/sql_base.cc
Text conflict in sql/sql_class.h
Text conflict in sql/sql_db.cc
Text conflict in sql/sql_delete.cc
Text conflict in sql/sql_insert.cc
Text conflict in sql/sql_lex.cc
Text conflict in sql/sql_lex.h
Text conflict in sql/sql_load.cc
Text conflict in sql/sql_table.cc
Text conflict in sql/sql_update.cc
Text conflict in sql/sql_view.cc
Conflict adding files to storage/innobase.  Created directory.
Conflict because storage/innobase is not versioned, but has versioned children.  Versioned directory.
Conflict adding file storage/innobase.  Moved existing file to storage/innobase.moved.
Conflict adding files to storage/innobase/handler.  Created directory.
Conflict because storage/innobase/handler is not versioned, but has versioned children.  Versioned directory.
Contents conflict in storage/innobase/handler/ha_innodb.cc
2010-01-07 15:39:11 +00:00
Marc Alff
3d91522561 WL#2360 Performance schema
Part IV: sql instrumentation
2010-01-06 22:42:07 -07:00
Sergei Golubchik
1ad5bb1a69 WL#4738 streamline/simplify @@variable creation process
Bug#16565 mysqld --help --verbose does not order variablesBug#20413 sql_slave_skip_counter is not shown in show variables
Bug#20415 Output of mysqld --help --verbose is incomplete
Bug#25430 variable not found in SELECT @@global.ft_max_word_len;
Bug#32902 plugin variables don't know their names
Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
Bug#34829 No default value for variable and setting default does not raise error
Bug#34834 ? Is accepted as a valid sql mode
Bug#34878 Few variables have default value according to documentation but error occurs  
Bug#34883 ft_boolean_syntax cant be assigned from user variable to global var.
Bug#37187 `INFORMATION_SCHEMA`.`GLOBAL_VARIABLES`: inconsistent status
Bug#40988 log_output_basic.test succeeded though syntactically false.
Bug#41010 enum-style command-line options are not honoured (maria.maria-recover fails)
Bug#42103 Setting key_buffer_size to a negative value may lead to very large allocations 
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
Bug#44797 plugins w/o command-line options have no disabling option in --help
Bug#46314 string system variables don't support expressions
Bug#46470 sys_vars.max_binlog_cache_size_basic_32 is broken
Bug#46586 When using the plugin interface the type "set" for options caused a crash.
Bug#47212 Crash in DBUG_PRINT in mysqltest.cc when trying to print octal number
Bug#48758 mysqltest crashes on sys_vars.collation_server_basic in gcov builds
Bug#49417 some complaints about mysqld --help --verbose output
Bug#49540 DEFAULT value of binlog_format isn't the default value
Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
Bug#49644 init_connect and \0
Bug#49645 init_slave and multi-byte characters
Bug#49646 mysql --show-warnings crashes when server dies


CMakeLists.txt:
  Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
client/mysql.cc:
  don't crash with --show-warnings when mysqld dies
config/ac-macros/plugins.m4:
  Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
include/my_getopt.h:
  comments
include/my_pthread.h:
  fix double #define
mysql-test/mysql-test-run.pl:
  run sys_vars suite by default
  properly recognize envirinment variables (e.g. MTR_MAX_SAVE_CORE) set to 0
  escape gdb command line arguments
mysql-test/suite/sys_vars/r/rpl_init_slave_func.result:
  init_slave+utf8 bug
mysql-test/suite/sys_vars/t/rpl_init_slave_func.test:
  init_slave+utf8 bug
mysys/my_getopt.c:
  Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
  Bug#46586 When using the plugin interface the type "set" for options caused a crash.
  Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
mysys/typelib.c:
  support for flagset
sql/ha_ndbcluster.cc:
  backport from telco tree
sql/item_func.cc:
  Bug#49644 init_connect and \0
  Bug#49645 init_slave and multi-byte characters
sql/sql_builtin.cc.in:
  Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
sql/sql_plugin.cc:
  Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
  Bug#32902 plugin variables don't know their names
  Bug#44797 plugins w/o command-line options have no disabling option in --help
sql/sys_vars.cc:
  all server variables are defined here
storage/myisam/ft_parser.c:
  remove unnecessary updates of param->quot
storage/myisam/ha_myisam.cc:
  myisam_* variables belong here
strings/my_vsnprintf.c:
  %o and %llx
unittest/mysys/my_vsnprintf-t.c:
  %o and %llx tests
vio/viosocket.c:
  bugfix: fix @@wait_timeout to work with socket timeouts (vs. alarm thread)
2009-12-22 10:35:56 +01:00
Konstantin Osipov
980e8b413e Merge next-mr -> next-4284. 2009-12-16 11:33:54 +03:00
Marc Alff
0531f85e16 Merge cleanup 2009-12-11 12:45:44 -07:00
Marc Alff
bea4ab9bb6 Merge mysql-next-mr (revno 2936) --> mysql-next-mr-marc 2009-12-11 01:58:13 -07:00
Marc Alff
c082955f06 WL#2360 Performance schema
Part III: mysys instrumentation
2009-12-09 20:19:51 -07:00
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
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
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
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
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
aeebede195 Backport of:
------------------------------------------------------------
revno: 2630.4.11
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Tue 2008-05-27 21:31:53 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Changed mysql_lock_tables() to be no longer responsible for
  reopening table if waiting for the lock on it was aborted.
  This allows to get rid of several annoying functions.


sql/ha_ndbcluster_binlog.cc:
  lock_tables() now also accepts set of options to be passed to
  mysql_lock_tables().
sql/lock.cc:
  Changed mysql_lock_tables() always requests caller to reopen
  table instead doing this on its own when waiting for lock was
  aborted. This allows us to get rid of several functions which
  were used in rare cases and significantly complicated our life.
sql/log_event_old.cc:
  lock_tables() now also accepts set of options to be passed
  to mysql_lock_tables().
sql/mysql_priv.h:
  Now mysql_lock_tables() always requests caller to reopen
  table instead doing this on its own when waiting for lock was
  aborted. So we no longer need wait_for_tables() and
  table_is_used() functions and MYSQL_LOCK_NOTIFY_IF_NEED_REOPEN
  flag.
  open_and_lock_table_derived() and lock_tables() now accept
  options to be passed to open_tables() and mysql_lock_tables()
  calls.
sql/sql_base.cc:
  Since now mysql_lock_tables() always requests caller to
  reopen table instead doing this on its own when waiting for
  lock was aborted we no longer need wait_for_tables(),
  table_is_used() and close_old_data_files() functions.
  open_and_lock_table_derived() and lock_tables() now accept
  options to be passed to open_tables() and mysql_lock_tables()
  calls. This was needed in order to get rid of redundant code
  in open_system_tables_for_read() function.
sql/sql_handler.cc:
  mysql_lock_tables() is now always requests reopen if waiting
  for lock is aborted. MYSQL_LOCK_NOTIFY_IF_NEED_REOPEN flag
  was removed.
sql/sql_insert.cc:
  handle_delayed_insert():
  Since mysql_lock_tables() is no longer responsible for
  reopening tables when waiting for lock was aborted we have
  to handle such situation outside of this function. To simplify
  this extracted code opening table for delayed insert thread to
  separate method of Delayed_insert class.
sql/sql_update.cc:
  lock_tables() now also accepts set of options to be passed
  to mysql_lock_tables().
2009-11-30 22:03:37 +03:00
Andrei Elkin
184d7b0250 mergin 5.1 -> rep+2 -> rep+3. create_table_from_dump issue will be merged on the next step 2009-11-30 20:20:26 +02:00
Konstantin Osipov
eff3780dd8 Initial import of WL#3726 "DDL locking for all metadata objects".
Backport of:
------------------------------------------------------------
revno: 2630.4.1
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Fri 2008-05-23 17:54:03 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.
------------------------------------------------------------

This is the first patch in series. It transforms the metadata 
locking subsystem to use a dedicated module (mdl.h,cc). No 
significant changes in the locking protocol. 
The import passes the test suite with the exception of 
deprecated/removed 6.0 features, and MERGE tables. The latter
are subject to a fix by WL#4144.
Unfortunately, the original changeset comments got lost in a merge,
thus this import has its own (largely insufficient) comments.

This patch fixes Bug#25144 "replication / binlog with view breaks".
Warning: this patch introduces an incompatible change:
Under LOCK TABLES, it's no longer possible to FLUSH a table that 
was not locked for WRITE.
Under LOCK TABLES, it's no longer possible to DROP a table or
VIEW that was not locked for WRITE.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:03:45 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:08:51 +0400
message:
  WL#3726 "DDL locking for all metadata objects"

  Fixed failing Windows builds by adding mdl.cc to the lists
  of files needed to build server/libmysqld on Windows.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 21:57:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Fix for assert failures in kill.test which occured when one
  tried to kill ALTER TABLE statement on merge table while it
  was waiting in wait_while_table_is_used() for other connections
  to close this table.

  These assert failures stemmed from the fact that cleanup code
  in this case assumed that temporary table representing new
  version of table was open with adding to THD::temporary_tables
  list while code which were opening this temporary table wasn't
  always fulfilling this.

  This patch changes code that opens new version of table to
  always do this linking in. It also streamlines cleanup process
  for cases when error occurs while we have new version of table
  open.

******
WL#3726 "DDL locking for all metadata objects"
Add libmysqld/mdl.cc to .bzrignore.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.6
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sun 2008-05-25 00:33:22 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Addition to the fix of assert failures in kill.test caused by
  changes for this worklog.


Make sure we close the new table only once.

.bzrignore:
  Add libmysqld/mdl.cc
libmysqld/CMakeLists.txt:
  Added mdl.cc to the list of files needed for building of libmysqld.
libmysqld/Makefile.am:
  Added files implementing new meta-data locking subsystem to the server.
mysql-test/include/handler.inc:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/create.result:
  Adjusted test case after change in implementation of CREATE TABLE
  ... SELECT.  We no longer have special check in open_table() which
  catches the case when we select from the table created. Instead we
  rely on unique_table() call which happens after opening and
  locking all tables.
mysql-test/r/flush.result:
  FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
  TABLES.  Updated test accordingly.
mysql-test/r/flush_table.result:
  Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
  locked for read. Updated test accordingly.
mysql-test/r/handler_innodb.result:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/handler_myisam.result:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/information_schema.result:
  Additional test for WL#3726 "DDL locking for all metadata
  objects".  Check that we use high-priority metadata lock requests
  when filling I_S tables.
  
  Rearrange tests to match 6.0 better (fewer merge conflicts).
mysql-test/r/kill.result:
  Added tests checking that DDL and DML statements waiting for
  metadata locks can be interrupted by KILL command.
mysql-test/r/lock.result:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation write locks on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/r/partition_column_prune.result:
  Update results (same results in 6.0), WL#3726
mysql-test/r/partition_pruning.result:
  Update results (same results in 6.0), WL#3726
mysql-test/r/ps_ddl.result:
  We no longer invalidate prepared CREATE TABLE ... SELECT statement
  if target table changes. This is OK since it is not strictly
  necessary.
  
  
  The first change is wrong, is caused by FLUSH TABLE
  now flushing all unused tables. This is a regression that
  Dmitri fixed in 6.0 in a follow up patch.
mysql-test/r/sp.result:
  Under LOCK TABLES we no longer allow accessing views which were
  not explicitly locked. To access view we need to obtain metadata
  lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/r/view.result:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation even "write locks" on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock
mysql-test/r/view_grant.result:
  ALTER VIEW implementation was changed to open a view only after
  checking that user which does alter has appropriate privileges on
  it. This means that in case when user's privileges are
  insufficient for this we won't check that new view definer is the
  same as original one or user performing alter has SUPER privilege.
  Adjusted test case accordingly.
mysql-test/r/view_multi.result:
  Added test case for bug#25144 "replication / binlog with view
  breaks".
mysql-test/suite/rpl/t/disabled.def:
  Disable test for deprecated features (they don't work with new MDL).
mysql-test/t/create.test:
  Adjusted test case after change in implementation of CREATE TABLE
  ... SELECT.  We no longer have special check in open_table() which
  catches the case when we select from the table created. Instead we
  rely on unique_table() call which happens after opening and
  locking all tables.
mysql-test/t/disabled.def:
  Disable merge.test, subject of WL#4144
mysql-test/t/flush.test:
  
  FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
  TABLES.  Updated test accordingly.
mysql-test/t/flush_table.test:
  Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
  locked for read. Updated test accordingly.
mysql-test/t/information_schema.test:
  Additional test for WL#3726 "DDL locking for all metadata
  objects".  Check that we use high-priority metadata lock requests
  when filling I_S tables.
  
  Rearrange the results for easier merges with 6.0.
mysql-test/t/kill.test:
  Added tests checking that DDL and DML statements waiting for
  metadata locks can be interrupted by KILL command.
mysql-test/t/lock.test:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation write locks on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/t/lock_multi.test:
  Adjusted test case to the changes of status in various places
  caused by change in implementation FLUSH TABLES WITH READ LOCK,
  which is now takes global metadata lock before flushing tables and
  therefore waits on at these places.
mysql-test/t/ps_ddl.test:
  We no longer invalidate prepared CREATE TABLE ... SELECT statement
  if target table changes. This is OK since it is not strictly
  necessary.
  
  
  The first change is wrong, is caused by FLUSH TABLE
  now flushing all unused tables. This is a regression that
  Dmitri fixed in 6.0 in a follow up patch.
mysql-test/t/sp.test:
  Under LOCK TABLES we no longer allow accessing views which were
  not explicitly locked. To access view we need to obtain metadata
  lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/t/trigger_notembedded.test:
  Adjusted test case to the changes of status in various places
  caused by change in implementation FLUSH TABLES WITH READ LOCK,
  which is now takes global metadata lock before flushing tables and
  therefore waits on at these places.
mysql-test/t/view.test:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation even "write locks" on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/t/view_grant.test:
  ALTER VIEW implementation was changed to open a view only after
  checking that user which does alter has appropriate privileges on
  it. This means that in case when user's privileges are
  insufficient for this we won't check that new view definer is the
  same as original one or user performing alter has SUPER privilege.
  Adjusted test case accordingly.
mysql-test/t/view_multi.test:
  Added test case for bug#25144 "replication / binlog with view
  breaks".
sql/CMakeLists.txt:
  Added mdl.cc to the list of files needed for building of server.
sql/Makefile.am:
  Added files implementing new meta-data locking subsystem to the
  server.
sql/event_db_repository.cc:
  
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when TABLE_LIST objects is also allocated
  there or on stack.
sql/ha_ndbcluster.cc:
  Adjusted code to work nicely with new metadata locking subsystem.
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/ha_ndbcluster_binlog.cc:
  Adjusted code to work with new metadata locking subsystem.
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/handler.cc:
  update_frm_version():
    Directly update TABLE_SHARE::mysql_version member instead of
    going through all TABLE instances for this table (old code was a
    legacy from pre-table-definition-cache days).
sql/lock.cc:
  Use new metadata locking subsystem. Threw away most of functions
  related to name locking as now one is supposed to use metadata
  locking API instead.  In lock_global_read_lock() and
  unlock_global_read_lock() in order to avoid problems with global
  read lock sneaking in at the moment when we perform FLUSH TABLES
  or ALTER TABLE under LOCK TABLES and when tables being reopened
  are protected only by metadata locks we also have to take global
  shared meta data lock.
sql/log_event.cc:
  Adjusted code to work with new metadata locking subsystem.  For
  tables open by slave thread for applying RBR events allocate
  memory for lock request object in the same chunk of memory as
  TABLE_LIST objects for them. In order to ensure that we keep these
  objects around until tables are open always close tables before
  calling Relay_log_info::clear_tables_to_lock(). Use new auxiliary
  Relay_log_info::slave_close_thread_tables() method to enforce
  this.
sql/log_event_old.cc:
  Adjusted code to work with new metadata locking subsystem.  Since
  for tables open by slave thread for applying RBR events memory for
  lock request object is allocated in the same chunk of memory as
  TABLE_LIST objects for them we have to ensure that we keep these
  objects around until tables are open. To ensure this we always
  close tables before calling
  Relay_log_info::clear_tables_to_lock(). To enfore this we use
  new auxiliary Relay_log_info::slave_close_thread_tables()
  method.
sql/mdl.cc:
  Implemented new metadata locking subsystem and API described in
  WL3726 "DDL locking for all metadata objects".
sql/mdl.h:
  Implemented new metadata locking subsystem and API described in
  WL3726 "DDL locking for all metadata objects".
sql/mysql_priv.h:
  - close_thread_tables()/close_tables_for_reopen() now has one more
    argument which indicates that metadata locks should be released
    but not removed from the context in order to be used later in
    mdl_wait_for_locks() and tdc_wait_for_old_version().
  - close_cached_table() routine is no longer public.
  - Thread waiting in wait_while_table_is_used() can be now killed
    so this function returns boolean to make caller aware of such
    situation.
  - We no longer have  table cache as separate entity instead used
    and unused TABLE instances are linked to TABLE_SHARE objects in
    table definition cache.
  - Now third argument of open_table() is also used for requesting
    table repair or auto-discovery of table's new definition. So its
    type was changed from bool to enum.
  - Added tdc_open_view() function for opening view by getting its
    definition from disk (and table cache in future).
  - reopen_name_locked_table() no longer needs "link_in" argument as
    now we have exclusive metadata locks instead of dummy TABLE
    instances when this function is called.
  - find_locked_table() now takes head of list of TABLE instances
    instead of always scanning through THD::open_tables list. Also
    added find_write_locked_table() auxiliary.
  - reopen_tables(), close_cached_tables() no longer have
    mark_share_as_old and wait_for_placeholder arguments. Instead of
    relying on this parameters and related behavior FLUSH TABLES
    WITH READ LOCK now takes global shared metadata lock.
  - We no longer need drop_locked_tables() and
    abort_locked_tables().
  - mysql_ha_rm_tables() now always assume that LOCK_open is not
    acquired by caller.
  - Added notify_thread_having_shared_lock() callback invoked by
    metadata locking subsystem when acquiring an exclusive lock, for
    each thread that has a conflicting shared metadata lock.
  - Introduced expel_table_from_cache() as replacement for
    remove_table_from_cache() (the main difference is that this new
    function assumes that caller follows metadata locking protocol
    and never waits).
  - Threw away most of functions related to name locking. One should
    use new metadata locking subsystem and API instead.
sql/mysqld.cc:
  Got rid of call initializing/deinitializing table cache since now
  it is embedded into table definition cache. Added calls for
  initializing/ deinitializing metadata locking subsystem.
sql/rpl_rli.cc:
  Introduced auxiliary Relay_log_info::slave_close_thread_tables()
  method which is used for enforcing that we always close tables
  open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
  objects for them.
sql/rpl_rli.h:
  Introduced auxiliary Relay_log_info::slave_close_thread_tables()
  method which is used for enforcing that we always close tables
  open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
  objects for them.
sql/set_var.cc:
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/sp_head.cc:
  For tables added to the statement's table list by prelocking
  algorithm we allocate these objects either on the same memory as
  corresponding table list elements or on THD::locked_tables_root
  (if we are building table list for LOCK TABLES).
sql/sql_acl.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.  Got rid of redundant code by using unlock_locked_tables()
  function.
sql/sql_base.cc:
  Changed code to use new MDL subsystem. Got rid of separate table
  cache.  Now used and unused TABLE instances are linked to the
  TABLE_SHAREs in table definition cache.
  
  check_unused():
    Adjusted code to the fact that we no longer have separate table
    cache.  Removed dead code.
  table_def_free():
    Free TABLE instances referenced from TABLE_SHARE objects before
    destroying table definition cache.
  get_table_share():
    Added assert which ensures that noone will be able to access
    table (and its share) without acquiring some kind of metadata
    lock first.
  close_handle_and_leave_table_as_lock():
    Adjusted code to the fact that TABLE instances now are linked to
    list in TABLE_SHARE.
  list_open_tables():
    Changed this function to use table definition cache instead of
    table cache.
  free_cache_entry():
    Unlink freed TABLE elements from the list of all TABLE instances
    for the table in TABLE_SHARE.
  kill_delayed_thread_for_table():
    Added auxiliary for killing delayed insert threads for
    particular table.
  close_cached_tables():
    Got rid of wait_for_refresh argument as we now rely on global
    shared metadata lock to prevent FLUSH WITH READ LOCK sneaking in
    when we are reopening tables. Heavily reworked this function to
    use new MDL code and not to rely on separate table cache entity.
  close_open_tables():
    We no longer have separate table cache.
  close_thread_tables():
    Release metadata locks after closing all tables. Added skip_mdl
    argument which allows us not to remove metadata lock requests
    from the context in case when we are going to use this requests
    later in mdl_wait_for_locks() and tdc_wait_for_old_versions().
  close_thread_table()/close_table_for_reopen():
    Since we no longer have separate table cache and all TABLE
    instances are linked to TABLE_SHARE objects in table definition
    cache we have to link/unlink TABLE object to/from appropriate
    lists in the share.
  name_lock_locked_table():
   Moved redundant code to find_write_locked_table() function and
    adjusted code to the fact that wait_while_table_is_used() can
    now return with an error if our thread is killed.
  reopen_table_entry():
    We no longer need "link_in" argument as with MDL we no longer
    call this function with dummy TABLE object pre-allocated and
    added to the THD::open_tables. Also now we add newly-open TABLE
    instance to the list of share's used TABLE instances.
  table_cache_insert_placeholder():
    Got rid of name-locking legacy.
  lock_table_name_if_not_cached():
    Moved to sql_table.cc the only place where it is used. It was
    also reimplemented using new MDL API.
  open_table():
    - Reworked this function to use new MDL subsystem.
    - Changed code to deal with table definition cache directly
      instead of going through separate table cache.
    - Now third argument is also used for requesting table repair
      or auto-discovery of table's new definition. So its type was
      changed from bool to enum.
  find_locked_table()/find_write_locked_table():
    Accept head of list of TABLE objects as first argument and use
    this list instead of always searching in THD::open_tables list.
    Also added auxiliary for finding write-locked locked tables.
  reopen_table():
    Adjusted function to work with new MDL subsystem and to properly
    manuipulate with lists of used/unused TABLE instaces in
    TABLE_SHARE.
  reopen_tables():
    Removed mark_share_as_old parameter. Instead of relying on it
    and related behavior FLUSH TABLES WITH READ LOCK now takes
    global shared metadata lock. Changed code after removing
    separate table cache.
  drop_locked_tables()/abort_locked_tables():
    Got rid of functions which are no longer needed.
    unlock_locked_tables():
    Moved this function from sql_parse.cc and changed it to release
    memory which was used for allocating metadata lock requests for
    tables open and locked by LOCK TABLES.
  tdc_open_view():
    Intoduced function for opening a view by getting its definition
    from disk (and table cache in future).
  reopen_table_entry():
    Introduced function for opening table definitions while holding
    exclusive metatadata lock on it.
  open_unireg_entry():
   Got rid of this function. Most of its functionality is relocated
    to open_table() and open_table_fini() functions, and some of it
    to reopen_table_entry() and tdc_open_view(). Also code
    resposible for auto-repair and auto-discovery of tables was
    moved to separate function.
  open_table_entry_fini():
    Introduced function which contains common actions which finalize
    process of TABLE object creation.
  auto_repair_table():
    Moved code responsible for auto-repair of table being opened
    here.
  handle_failed_open_table_attempt()
    Moved code responsible for handling failing attempt to open
    table to one place (retry due to lock conflict/old version,
    auto-discovery and repair).
  open_tables():
    - Flush open HANDLER tables if they have old version of if there
      is conflicting metadata lock against them (before this moment
      we had this code in open_table()).
    - When we open view which should be processed via derived table
      on the second execution of prepared statement or stored
      routine we still should call open_table() for it in order to
      obtain metadata lock on it and prepare its security context.
    - In cases when we discover that some special handling of
      failure to open table is needed call
      handle_failed_open_table_attempt() which handles all such
      scenarios.
  open_ltable():
    Handling of various special scenarios of failure to open a table
    was moved to separate handle_failed_open_table_attempt()
    function.
  remove_db_from_cache():
    Removed this function as it is no longer used.
  notify_thread_having_shared_lock():
    Added callback which is invoked by MDL subsystem when acquiring
    an exclusive lock, for each thread that has a conflicting shared
    metadata lock.
  expel_table_from_cache():
    Introduced function for removing unused TABLE instances. Unlike
    remove_table_from_cache() it relies on caller following MDL
    protocol and having appropriate locks when calling it and thus
    does not do any waiting if table is still in use.
  tdc_wait_for_old_version():
    Added function which allows open_tables() to wait in cases when
    we discover that we should back-off due to presence of old
    version of table.
  abort_and_upgrade_lock():
    Use new MDL calls.
  mysql_wait_completed_table():
    Got rid of unused function.
  open_system_tables_for_read/for_update()/performance_schema_table():
    Allocate MDL_LOCK objects on execution memory root in cases when
    TABLE_LIST objects for corresponding tables is allocated on
    stack.
  close_performance_schema_table():
    Release metadata locks after closing tables.
  ******
  Use I_P_List for free/used tables list in the table share.
sql/sql_binlog.cc:
  Use Relay_log_info::slave_close_thread_tables() method to enforce
  that we always close tables open for RBR before deallocating
  TABLE_LIST elements and MDL_LOCK objects for them.
sql/sql_class.cc:
  Added meta-data locking contexts as part of Open_tables_state
  context.  Also introduced THD::locked_tables_root memory root
  which is to be used for allocating MDL_LOCK objects for tables in
  LOCK TABLES statement (end of lifetime for such objects is UNLOCK
  TABLES so we can't use statement or execution root for them).
sql/sql_class.h:
  Added meta-data locking contexts as part of Open_tables_state
  context.  Also introduced THD::locked_tables_root memory root
  which is to be used for allocating MDL_LOCK objects for tables in
  LOCK TABLES statement (end of lifetime for such objects is UNLOCK
  TABLES so we can't use statement or execution root for them).
  
  Note: handler_mdl_context and locked_tables_root and
  mdl_el_root will be removed by subsequent patches.
sql/sql_db.cc:
  mysql_rm_db() does not really need to call remove_db_from_cache()
  as it drops each table in the database using
  mysql_rm_table_part2(), which performs all necessary operations on
  table (definition) cache.
sql/sql_delete.cc:
  Use the new metadata locking API for TRUNCATE.
sql/sql_handler.cc:
  Changed HANDLER implementation to use new metadata locking
  subsystem.  Note that MDL_LOCK objects for HANDLER tables are
  allocated in the same chunk of heap memory as TABLE_LIST object
  for those tables.
sql/sql_insert.cc:
  mysql_insert():
    find_locked_table() now takes head of list of TABLE object as
    its argument instead of always scanning through THD::open_tables
    list.
  handle_delayed_insert():
    Allocate metadata lock request object for table open by delayed
    insert thread on execution memroot.  create_table_from_items():
    We no longer allocate dummy TABLE objects for tables being
    created if they don't exist. As consequence
    reopen_name_locked_table() no longer has link_in argument.
    open_table() now has one more argument which is not relevant for
    temporary tables.
sql/sql_parse.cc:
  - Moved unlock_locked_tables() routine to sql_base.cc and made
    available it in other files. Got rid of some redundant code by
    using this function.
  - Replaced boolean TABLE_LIST::create member with enum
    open_table_type member.
  - Use special memory root for allocating MDL_LOCK objects for
    tables open and locked by LOCK TABLES (these object should live
    till UNLOCK TABLES so we can't allocate them on statement nor
    execution memory root). Also properly set metadata lock
    upgradability attribure for those tables.
  - Under LOCK TABLES it is no longer allowed to flush tables which
    are not write-locked as this breaks metadata locking protocol
    and thus potentially might lead to deadlock.
  - Added auxiliary adjust_mdl_locks_upgradability() function.
sql/sql_partition.cc:
  Adjusted code to the fact that reopen_tables() no longer has
  "mark_share_as_old" argument. Got rid of comments which are no
  longer true.
sql/sql_plist.h:
  Added I_P_List template class for parametrized intrusive doubly
  linked lists and I_P_List_iterator for corresponding iterator.
  Unlike for I_List<> list elements of such list can participate in
  several lists. Unlike List<> such lists are doubly-linked and
  intrusive.
sql/sql_plugin.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.
sql/sql_prepare.cc:
  Replaced boolean TABLE_LIST::create member with enum
  open_table_type member.  This allows easily handle situation in
  which instead of opening the table we want only to take exclusive
  metadata lock on it.
sql/sql_rename.cc:
  Use new metadata locking subsystem in implementation of RENAME
  TABLE.
sql/sql_servers.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables. Got rid of redundant code by using unlock_locked_tables()
  function.
sql/sql_show.cc:
  Acquire shared metadata lock when we are getting information for
  I_S table directly from TABLE_SHARE without doing full-blown table
  open.  We use high priority lock request in this situation in
  order to avoid deadlocks.
  Also allocate metadata lock requests objects (MDL_LOCK) on
  execution memory root in cases when TABLE_LIST objects are also
  allocated there
sql/sql_table.cc:
  mysql_rm_table():
    Removed comment which is no longer relevant.
  mysql_rm_table_part2():
    Now caller of mysql_ha_rm_tables() should not own LOCK_open.
    Adjusted code to use new metadata locking subsystem instead of
    name-locks.
  lock_table_name_if_not_cached():
    Moved this function from sql_base.cc to this file and
    reimplemented it using metadata locking API.
  mysql_create_table():
    Adjusted code to use new MDL API.
  wait_while_table_is_used():
    Changed function to use new MDL subsystem. Made thread waiting
    in it killable (this also led to introduction of return value so
    caller can distinguish successful executions from situations
    when waiting was aborted).
  close_cached_tables():
    Thread waiting in this function is killable now. As result it
    has return value for distinguishing between succes and failure.
    Got rid of redundant boradcast_refresh() call.
  prepare_for_repair():
    Use MDL subsystem instead of name-locks.
  mysql_admin_table():
    mysql_ha_rm_tables() now always assumes that caller doesn't own
    LOCK_open.
  mysql_repair_table():
    We should mark all elements of table list as requiring
    upgradable metadata locks.
  mysql_create_table_like():
    Use new MDL subsystem instead of name-locks.
  create_temporary_tables():
    We don't need to obtain metadata locks when creating temporary
    table.
  mysql_fast_or_online_alter_table():
    Thread waiting in wait_while_table_is_used() is now killable.
  mysql_alter_table():
    Adjusted code to work with new MDL subsystem and to the fact
    that threads waiting in what_while_table_is_used() and
    close_cached_table() are now killable.
sql/sql_test.cc:
  We no longer have separate table cache. TABLE instances are now
  associated with/linked to TABLE_SHARE objects in table definition
  cache.
sql/sql_trigger.cc:
  Adjusted code to work with new metadata locking subsystem.  Also
  reopen_tables() no longer has mark_share_as_old argument (Instead
  of relying on this parameter and related behavior FLUSH TABLES
  WITH READ LOCK now takes global shared metadata lock).
sql/sql_udf.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.
sql/sql_update.cc:
  Adjusted code to work with new meta-data locking subsystem.
sql/sql_view.cc:
  Added proper meta-data locking to implementations of
  CREATE/ALTER/DROP VIEW statements. Now we obtain exclusive
  meta-data lock on a view before creating/ changing/dropping it.
  This ensures that all concurrent statements that use this view
  will finish before our statement will proceed and therefore we
  will get correct order of statements in the binary log.
  Also ensure that TABLE_LIST::mdl_upgradable attribute is properly
  propagated for underlying tables of view.
sql/table.cc:
  Added auxiliary alloc_mdl_locks() function for allocating metadata
  lock request objects for all elements of table list.
sql/table.h:
  TABLE_SHARE:
    Got rid of unused members. Introduced members for storing lists
    of used and unused TABLE objects for this share.
  TABLE:
    Added members for linking TABLE objects into per-share lists of
    used and unused TABLE instances. Added member for holding
    pointer to metadata lock for this table.
  TABLE_LIST:
    Replaced boolean TABLE_LIST::create member with enum
    open_table_type member.  This allows easily handle situation in
    which instead of opening the table we want only to take
    exclusive meta-data lock on it (we need this in order to handle
    ALTER VIEW and CREATE VIEW statements).
    Introduced new mdl_upgradable member for marking elements of
    table list for which we need to take upgradable shared metadata
    lock instead of plain shared metadata lock.  Added pointer for
    holding pointer to MDL_LOCK for the table.
  Added auxiliary alloc_mdl_locks() function for allocating metadata
  lock requests objects for all elements of table list.  Added
  auxiliary set_all_mdl_upgradable() function for marking all
  elements in table list as requiring upgradable metadata locks.
storage/myisammrg/ha_myisammrg.cc:
  Allocate MDL_LOCK objects for underlying tables of MERGE table.
  To be reworked once Ingo pushes his patch for WL4144.
2009-11-30 18:55:03 +03:00
Mattias Jonsson
d8d8efc88e Bug#32115: Bad use of Name_resolution_context from current LEX in partitioning
port from mysql-next (5.4?) to mysql-next-mr-bugfixes (5.5/5.6?)

3477 Mikael Ronstrom	2009-07-29
Bug#32115, made use of local lex object to avoid side effects of opening partitioned
tables

3478 Mikael Ronstrom	2009-07-29
Bug#32115, added an extra test in debug builds to ensure no dangling pointers to the
old lex object is still around

3479 Mikael Ronstrom	2009-07-29
Bug#32115, Removed an assert that was no longer needed

3480 Mikael Ronstrom	2009-08-05
Bug#32115, fixed review comments

3481 Mikael Ronstrom	2009-08-07
Bug#32115, remove now obsolete lex_start calls
2009-11-20 01:20:08 +01:00
Andrei Elkin
7eb789a723 merging 5.1 main -> 5.1-rep+2 -> 5.1-rep+3; binlog_unsafe , rpl_mysql_upgrade fail and are under treatment 2009-11-10 20:45:15 +02:00
Alexander Nozdrin
b712dce3d5 Auto-merge from mysql-next-mr. 2009-11-10 10:31:33 +03:00
Alexander Nozdrin
cd14c47c99 Manual merge from mysql-trunk-merge. 2009-11-05 23:28:35 +03:00
Alexander Nozdrin
d476bbb0be Auto-merge from mysql-next-mr. 2009-11-05 15:08:37 +03:00
Alfranio Correia
19c380aaff WL#2687 WL#5072 BUG#40278 BUG#47175
Non-transactional updates that take place inside a transaction present problems
for logging because they are visible to other clients before the transaction
is committed, and they are not rolled back even if the transaction is rolled
back. It is not always possible to log correctly in statement format when both
transactional and non-transactional tables are used in the same transaction.

In the current patch, we ensure that such scenario is completely safe under the
ROW and MIXED modes.
2009-11-03 19:02:56 +00:00
Sergei Golubchik
319847a4ec backport of dbug extensions from 6.0:
function/ syntax
  glob(7) wildcards
  unit tests
2009-10-30 19:13:58 +01:00
Alexander Nozdrin
2dc132b209 Merge from mysql-next-mr. 2009-10-23 15:22:21 +04:00
Georgi Kodinov
7b4ef910f7 Bug #40877: multi statement execution fails in 5.1.30
Implemented the server infrastructure for the fix:

1. Added a function LEX_STRING *thd_query_string(THD) to return
a LEX_STRING structure instead of char *.
This is the function that must be called in innodb instead of 
thd_query()

2. Did some encapsulation in THD : aggregated thd_query and 
thd_query_length into a LEX_STRING and made accessor and mutator 
methods for easy code updating. 

3. Updated the server code to use the new methods where applicable.
2009-10-16 13:29:42 +03:00
Konstantin Osipov
9b41c7532d Backport of:
----------------------------------------------------------
revno: 2617.22.5
committer: Konstantin Osipov <kostja@sun.com>
branch nick: mysql-6.0-runtime
timestamp: Tue 2009-01-27 05:08:48 +0300
message:
  Remove non-prefixed use of HASH.
  Always use my_hash_init(), my_hash_inited(), my_hash_search(),
  my_hash_element(), my_hash_delete(), my_hash_free() rather
  than non-prefixed counterparts (hash_init(), etc).
  Remove the backward-compatible defines.
2009-10-14 20:37:38 +04:00