database/mariadb
database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-05-25 13:42:52 +03:00
Code
60,163 Commits 3,002 Branches 355 Tags
Commit Graph

1567 Commits

Author SHA1 Message Date
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
Dmitry Lenev
eba5d30e67 Implement new type-of-operation-aware metadata locks. 
Add a wait-for graph based deadlock detector to the
MDL subsystem.

Fixes bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock" and
bug #37346 "innodb does not detect deadlock between update and
alter table".

The first bug manifested itself as an unwarranted abort of a
transaction with ER_LOCK_DEADLOCK error by a concurrent ALTER
statement, when this transaction tried to repeat use of a
table, which it has already used in a similar fashion before
ALTER started.

The second bug showed up as a deadlock between table-level
locks and InnoDB row locks, which was "detected" only after
innodb_lock_wait_timeout timeout.

A transaction would start using the table and modify a few
rows.
Then ALTER TABLE would come in, and start copying rows
into a temporary table. Eventually it would stumble on
the modified records and get blocked on a row lock.
The first transaction would try to do more updates, and get
blocked on thr_lock.c lock.
This situation of circular wait would only get resolved
by a timeout.

Both these bugs stemmed from inadequate solutions to the
problem of deadlocks occurring between different
locking subsystems.

In the first case we tried to avoid deadlocks between metadata
locking and table-level locking subsystems, when upgrading shared
metadata lock to exclusive one.
Transactions holding the shared lock on the table and waiting for
some table-level lock used to be aborted too aggressively.

We also allowed ALTER TABLE to start in presence of transactions
that modify the subject table. ALTER TABLE acquires
TL_WRITE_ALLOW_READ lock at start, and that block all writes
against the table (naturally, we don't want any writes to be lost
when switching the old and the new table). TL_WRITE_ALLOW_READ
lock, in turn, would block the started transaction on thr_lock.c
lock, should they do more updates. This, again, lead to the need
to abort such transactions.

The second bug occurred simply because we didn't have any
mechanism to detect deadlocks between the table-level locks
in thr_lock.c and row-level locks in InnoDB, other than
innodb_lock_wait_timeout.

This patch solves both these problems by moving lock conflicts
which are causing these deadlocks into the metadata locking
subsystem, thus making it possible to avoid or detect such
deadlocks inside MDL.

To do this we introduce new type-of-operation-aware metadata
locks, which allow MDL subsystem to know not only the fact that
transaction has used or is going to use some object but also what
kind of operation it has carried out or going to carry out on the
object.

This, along with the addition of a special kind of upgradable
metadata lock, allows ALTER TABLE to wait until all
transactions which has updated the table to go away.
This solves the second issue.
Another special type of upgradable metadata lock is acquired
by LOCK TABLE WRITE. This second lock type allows to solve the
first issue, since abortion of table-level locks in event of
DDL under LOCK TABLES becomes also unnecessary.

Below follows the list of incompatible changes introduced by
this patch:

- From now on, ALTER TABLE and CREATE/DROP TRIGGER SQL (i.e. those
  statements that acquire TL_WRITE_ALLOW_READ lock)
  wait for all transactions which has *updated* the table to
  complete.

- From now on, LOCK TABLES ... WRITE, REPAIR/OPTIMIZE TABLE
  (i.e. all statements which acquire TL_WRITE table-level lock) wait
  for all transaction which *updated or read* from the table
  to complete.
  As a consequence, innodb_table_locks=0 option no longer applies
  to LOCK TABLES ... WRITE.

- DROP DATABASE, DROP TABLE, RENAME TABLE no longer abort
  statements or transactions which use tables being dropped or
  renamed, and instead wait for these transactions to complete.

- Since LOCK TABLES WRITE now takes a special metadata lock,
  not compatible with with reads or writes against the subject table
  and transaction-wide, thr_lock.c deadlock avoidance algorithm
  that used to ensure absence of deadlocks between LOCK TABLES
  WRITE and other statements is no longer sufficient, even for
  MyISAM. The wait-for graph based deadlock detector of MDL
  subsystem may sometimes be necessary and is involved. This may
  lead to ER_LOCK_DEADLOCK error produced for multi-statement
  transactions even if these only use MyISAM:

  session 1:         session 2:
  begin;

  update t1 ...      lock table t2 write, t1 write;
                     -- gets a lock on t2, blocks on t1

  update t2 ...
  (ER_LOCK_DEADLOCK)

- Finally,  support of LOW_PRIORITY option for LOCK TABLES ... WRITE
  was abandoned.
  LOCK TABLE ... LOW_PRIORITY WRITE from now on has the same
  priority as the usual LOCK TABLE ... WRITE.
  SELECT HIGH PRIORITY no longer trumps LOCK TABLE ... WRITE  in
  the wait queue.

- We do not take upgradable metadata locks on implicitly
  locked tables. So if one has, say, a view v1 that uses
  table t1, and issues:
  LOCK TABLE v1 WRITE;
  FLUSH TABLE t1; -- (or just 'FLUSH TABLES'),
  an error is produced.
  In order to be able to perform DDL on a table under LOCK TABLES,
  the table must be locked explicitly in the LOCK TABLES list.

mysql-test/include/handler.inc:
  Adjusted test case to trigger an execution path on which bug 41110
  "crash with handler command when used concurrently with alter
  table" and bug 41112 "crash in mysql_ha_close_table/get_lock_data
  with alter table" were originally discovered. Left old test case
  which no longer triggers this execution path for the sake of
  coverage.
  Added test coverage for HANDLER SQL statements and type-aware
  metadata locks.
  Added a test for the global shared lock and HANDLER SQL.
  Updated tests to take into account that the old simple deadlock
  detection heuristics was replaced with a graph-based deadlock
  detector.
mysql-test/r/debug_sync.result:
  Updated results (see debug_sync.test).
mysql-test/r/handler_innodb.result:
  Updated results (see handler.inc test).
mysql-test/r/handler_myisam.result:
  Updated results (see handler.inc test).
mysql-test/r/innodb-lock.result:
  Updated results (see innodb-lock.test).
mysql-test/r/innodb_mysql_lock.result:
  Updated results (see innodb_mysql_lock.test).
mysql-test/r/lock.result:
  Updated results (see lock.test).
mysql-test/r/lock_multi.result:
  Updated results (see lock_multi.test).
mysql-test/r/lock_sync.result:
  Updated results (see lock_sync.test).
mysql-test/r/mdl_sync.result:
  Updated results (see mdl_sync.test).
mysql-test/r/sp-threads.result:
  SHOW PROCESSLIST output has changed due to the fact that waiting
  for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/r/truncate_coverage.result:
  Updated results (see truncate_coverage.test).
mysql-test/suite/funcs_1/datadict/processlist_val.inc:
  SELECT FROM I_S.PROCESSLIST output has changed due to fact that
  waiting for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/suite/funcs_1/r/processlist_val_no_prot.result:
  SELECT FROM I_S.PROCESSLIST output has changed due to fact that
  waiting for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/suite/rpl/t/rpl_sp.test:
  Updated to a new SHOW PROCESSLIST state name.
mysql-test/t/debug_sync.test:
  Use LOCK TABLES READ instead of LOCK TABLES WRITE as the latter
  no longer allows to trigger execution path involving waiting on
  thr_lock.c lock and therefore reaching debug sync-point covered
  by this test.
mysql-test/t/innodb-lock.test:
  Adjusted test case to the fact that innodb_table_locks=0 option is
  no longer supported, since LOCK TABLES WRITE handles all its
  conflicts within MDL subsystem.
mysql-test/t/innodb_mysql_lock.test:
  Added test for bug #37346 "innodb does not detect deadlock between
  update and alter table".
mysql-test/t/lock.test:
  Added test coverage which checks the fact that we no longer support
  DDL under LOCK TABLES on tables which were locked implicitly.
  Adjusted existing test cases accordingly.
mysql-test/t/lock_multi.test:
  Added test for bug #46272 "MySQL 5.4.4, new MDL: unnecessary
  deadlock".  Adjusted other test cases to take into account the
  fact that waiting for LOCK TABLES ... WRITE now happens within MDL
  subsystem.
mysql-test/t/lock_sync.test:
  Since LOCK TABLES ... WRITE now takes SNRW metadata lock for
  tables locked explicitly we have to implicitly lock InnoDB tables
  (through view) to trigger the table-level lock conflict between
  TL_WRITE and TL_WRITE_ALLOW_WRITE.
mysql-test/t/mdl_sync.test:
  Added basic test coverage for type-of-operation-aware metadata
  locks. Also covered with tests some use cases involving HANDLER
  statements in which a deadlock could arise.
  Adjusted existing tests to take type-of-operation-aware MDL into
  account.
mysql-test/t/multi_update.test:
  Update to a new SHOW PROCESSLIST state name.
mysql-test/t/truncate_coverage.test:
  Adjusted test case after making LOCK TABLES WRITE to wait until
  transactions that use the table to be locked are completed.
  Updated to the changed name of DEBUG_SYNC point.
sql/handler.cc:
  Global read lock functionality has been
  moved into a class.
sql/lock.cc:
  Global read lock functionality has been
  moved into a class.
  Updated code to use the new MDL API.
sql/mdl.cc:
  Introduced new type-of-operation aware metadata locks.
  To do this:
  - Changed MDL_lock to use one list for waiting requests and one
    list for granted requests. For each list, added a bitmap
    that holds information what lock types a list contains.
    Added a helper class MDL_lock::List to manipulate with granted
    and waited lists while keeping the bitmaps in sync
    with list contents.
  - Changed lock-compatibility functions to use bitmaps that
    define compatibility.
  - Introduced a graph based deadlock detector inspired by
    waiting_threads.c from Maria implementation.
  - Now that we have a deadlock detector, and no longer have
    a global lock to protect individual lock objects, but rather
    use an rw lock per object, removed redundant code for upgrade,
    and the global read lock. Changed the MDL API to
    no longer require the caller to acquire the global
    intention exclusive lock by means of a separate method.
    Removed a few more methods that became redundant.
  - Removed deadlock detection heuristic, it has been made
    obsolete by the deadlock detector.
  - With operation-type-aware metadata locks, MDL subsystem has
    become aware of potential conflicts between DDL and open
    transactions. This made it possible to remove calls to
    mysql_abort_transactions_with_shared_lock() from acquisition
    paths for exclusive lock and lock upgrade. Now we can simply
    wait for these transactions to complete without fear of
    deadlock. Function mysql_lock_abort() has also become
    unnecessary for all conflicting cases except when a DDL
    conflicts with a connection that has an open HANDLER.
sql/mdl.h:
  Introduced new type-of-operation aware metadata locks.
  Introduced a graph based deadlock detector and supporting
  methods.
  Added comments.
  God rid of redundant API calls.
  Renamed m_lt_or_ha_sentinel to m_trans_sentinel,
  since now it guards the global read lock as well as
  LOCK TABLES and HANDLER locks.
sql/mysql_priv.h:
  Moved the global read lock functionality into a
  class.
  Added MYSQL_OPEN_FORCE_SHARED_MDL flag which forces
  open_tables() to take MDL_SHARED on tables instead of
  metadata locks specified in the parser. We use this to
  allow PREPARE run concurrently in presence of
  LOCK TABLES ... WRITE.
  Added signature for find_table_for_mdl_ugprade().
sql/set_var.cc:
  Global read lock functionality has been
  moved into a class.
sql/sp_head.cc:
  When creating TABLE_LIST elements for prelocking or
  system tables set the type of request for metadata
  lock according to the operation that will be performed
  on the table.
sql/sql_base.cc:
  - Updated code to use the new MDL API.
  - In order to avoid locks starvation we take upgradable
    locks all at once. As result implicitly locked tables no
    longer get an upgradable lock. Consequently DDL and FLUSH
    TABLES for such tables is prohibited.
    find_write_locked_table() was replaced by
    find_table_for_mdl_upgrade() function.
    open_table() was adjusted to return TABLE instance with
    upgradable ticket when necessary.
  - We no longer wait for all locks on OT_WAIT back off
    action -- only on the lock that caused the wait
    conflict. Moreover, now we distinguish cases when we
    have to wait due to conflict in MDL and old version
    of table in TDC.
  - Upate mysql_notify_threads_having_share_locks()
    to only abort thr_lock.c waits of threads that
    have open HANDLERs, since lock conflicts with only
    these threads now can lead to deadlocks not detectable
    by the MDL deadlock detector.
  - Remove mysql_abort_transactions_with_shared_locks()
    which is no longer needed.
sql/sql_class.cc:
  Global read lock functionality has been moved into a class.
  Re-arranged code in THD::cleanup() to simplify assert.
sql/sql_class.h:
  Introduced class to incapsulate global read lock
  functionality.
  Now sentinel in MDL subsystem guards the global read lock
  as well as LOCK TABLES and HANDLER locks. Adjusted code
  accordingly.
sql/sql_db.cc:
  Global read lock functionality has been moved into a class.
sql/sql_delete.cc:
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result
  TRUNCATE TABLE is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_handler.cc:
  Inform MDL_context about presence of open HANDLERs.
  Since HANLDERs break MDL protocol by acquiring table-level
  lock while holding only S metadata lock on a table MDL
  subsystem should take special care about such contexts (Now
  this is the only case when mysql_lock_abort() is used).
sql/sql_parse.cc:
  Global read lock functionality has been moved into a class.
  Do not take upgradable metadata locks when opening tables
  for CREATE TABLE SELECT as it is not necessary and limits
  concurrency.
  When initializing TABLE_LIST objects before adding them
  to the table list set the type of request for metadata lock
  according to the operation that will be performed on the
  table.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result FLUSH
  TABLES is no longer allowed for such tables.
sql/sql_prepare.cc:
  Use MYSQL_OPEN_FORCE_SHARED_MDL flag when opening
  tables during PREPARE. This allows PREPARE to run
  concurrently in presence of LOCK TABLES ... WRITE.
sql/sql_rename.cc:
  Global read lock functionality has been moved into a class.
sql/sql_show.cc:
  Updated code to use the new MDL API.
sql/sql_table.cc:
  Global read lock functionality has been moved into a class.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result DROP
  TABLE is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_trigger.cc:
  Global read lock functionality has been moved into a class.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result
  CREATE/DROP TRIGGER is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_view.cc:
  Global read lock functionality has been moved into a class.
  Fixed results of wrong merge that led to misuse of GLR API.
  CREATE VIEW statement is not a commit statement.
sql/table.cc:
  When resetting TABLE_LIST objects for PS or SP re-execution
  set the type of request for metadata lock according to the
  operation that will be performed on the table. Do the same
  in auxiliary function initializing metadata lock requests
  in a table list.
sql/table.h:
  When initializing TABLE_LIST objects set the type of request
  for metadata lock according to the operation that will be
  performed on the table.
sql/transaction.cc:
  Global read lock functionality has been moved into a class.
 2010-02-01 14:43:06 +03:00
Dmitry Lenev
6ddd01c27a Patch that changes metadata locking subsystem to use mutex per lock and 
condition variable per context instead of one mutex and one conditional
variable for the whole subsystem.

This should increase concurrency in this subsystem.

It also opens the way for further changes which are necessary to solve
such bugs as bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock"
and bug #37346 "innodb does not detect deadlock between update and alter
table".

Two other notable changes done by this patch:

- MDL subsystem no longer implicitly acquires global intention exclusive
  metadata lock when per-object metadata lock is acquired. Now this has
  to be done by explicit calls outside of MDL subsystem.
- Instead of using separate MDL_context for opening system tables/tables
  for purposes of I_S we now create MDL savepoint in the main context
  before opening tables and rollback to this savepoint after closing
  them. This means that it is now possible to get ER_LOCK_DEADLOCK error
  even not inside a transaction. This might happen in unlikely case when
  one runs DDL on one of system tables while also running DDL on some
  other tables. Cases when this ER_LOCK_DEADLOCK error is not justified
  will be addressed by advanced deadlock detector for MDL subsystem which
  we plan to implement.

mysql-test/include/handler.inc:
  Adjusted handler_myisam.test and handler_innodb.test to the fact that
  exclusive metadata locks on tables are now acquired according to
  alphabetical order of fully qualified table names instead of order
  in which tables are mentioned in statement.
mysql-test/r/handler_innodb.result:
  Adjusted handler_myisam.test and handler_innodb.test to the fact that
  exclusive metadata locks on tables are now acquired according to
  alphabetical order of fully qualified table names instead of order
  in which tables are mentioned in statement.
mysql-test/r/handler_myisam.result:
  Adjusted handler_myisam.test and handler_innodb.test to the fact that
  exclusive metadata locks on tables are now acquired according to
  alphabetical order of fully qualified table names instead of order
  in which tables are mentioned in statement.
mysql-test/r/mdl_sync.result:
  Adjusted mdl_sync.test to the fact that exclusive metadata locks on
  tables are now acquired according to alphabetical order of fully
  qualified table names instead of order in which tables are mentioned
  in statement.
mysql-test/t/mdl_sync.test:
  Adjusted mdl_sync.test to the fact that exclusive metadata locks on
  tables are now acquired according to alphabetical order of fully
  qualified table names instead of order in which tables are mentioned
  in statement.
sql/events.cc:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. To support this
  change methods of THD responsible for saving/restoring open table
  state were changed to use Open_tables_backup class which in addition
  to Open_table_state has a member for this savepoint. As result code
  opening/closing system tables was changed to use Open_tables_backup
  instead of Open_table_state class as well.
sql/ha_ndbcluster.cc:
  Since manipulations with open table state no longer install proxy
  MDL_context it does not make sense to perform them in order to
  satisfy assert in mysql_rm_tables_part2(). Removed them per agreement
  with Cluster team. This has not broken test suite since scenario in
  which deadlock can occur and assertion fails is not covered by tests.
sql/lock.cc:
  MDL subsystem no longer implicitly acquires global intention exclusive
  metadata lock when per-object exclusive metadata lock is acquired.
  Now this has to be done by explicit calls outside of MDL subsystem.
sql/log.cc:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. To support this
  change methods of THD responsible for saving/restoring open table
  state were changed to use Open_tables_backup class which in addition
  to Open_table_state has a member for this savepoint. As result code
  opening/closing system tables was changed to use Open_tables_backup
  instead of Open_table_state class as well.
sql/mdl.cc:
  Changed metadata locking subsystem to use mutex per lock and condition
  variable per context instead of one mutex and one conditional variable
  for the whole subsystem.
  Changed approach to handling of global metadata locks. Instead of
  implicitly acquiring intention exclusive locks when user requests
  per-object upgradeable or exclusive locks now we require them to be
  acquired explicitly in the same way as ordinary metadata locks.
  In fact global lock are now ordinary metadata locks in new GLOBAL
  namespace.
  
  To implement these changes:
  - Removed LOCK_mdl mutex and COND_mdl condition variable.
  - Introduced MDL_lock::m_mutex mutexes which protect individual lock
    objects.
  - Replaced mdl_locks hash with MDL_map class, which has hash for
    MDL_lock objects as a member and separate mutex which protects this
    hash. Methods of this class allow to find(), find_or_create() or
    remove() MDL_lock objects in concurrency-friendly fashion (i.e.
    for most common operation, find_or_create(), we don't acquire
    MDL_lock::m_mutex while holding MDL_map::m_mutex. Thanks to MikaelR
    for this idea and benchmarks!). Added three auxiliary members to
    MDL_lock class (m_is_destroyed, m_ref_usage, m_ref_release) to
    support this concurrency-friendly behavior.
  - Introduced MDL_context::m_ctx_wakeup_cond condition variable to be
    used for waiting until this context's pending request can be
    satisfied or its thread has to perform actions to resolve potential
    deadlock. Context which want to wait add ticket corresponding to the
    request to an appropriate queue of waiters in MDL_lock object so
    they can be noticed when other contexts change state of lock and be
    awaken by them by signalling on MDL_context::m_ctx_wakeup_cond.
    As consequence MDL_ticket objects has to be used for any waiting
    in metadata locking subsystem including one which happens in
    MDL_context::wait_for_locks() method.
    Another consequence is that MDL_context is no longer copyable and
    can't be saved/restored when working with system tables.
  - Made MDL_lock an abstract class, which delegates specifying exact
    compatibility matrix to its descendants. Added MDL_global_lock child
    class for global lock (The old is_lock_type_compatible() method
    became can_grant_lock() method of this class). Added MDL_object_lock
    class to represent per-object lock (The old MDL_lock::can_grant_lock()
    became its method). Choice between two classes happens based on MDL
    namespace in MDL_lock::create() method.
  - Got rid of MDL_lock::type member as its meaning became ambigous for
    global locks.
  - To simplify waking up of contexts waiting for lock split waiting queue
    in MDL_lock class in two queues. One for pending requests for exclusive
    (including intention exclusive) locks and another for requests for
    shared locks.
  - Added virtual wake_up_waiters() method to MDL_lock, MDL_global_lock and
    MDL_object_lock classes which allows to wake up waiting contexts after
    state of lock changes. Replaced old duplicated code with calls to this
    method.
  - Adjusted MDL_context::try_acquire_shared_lock()/exclusive_lock()/
    global_shared_lock(), MDL_ticket::upgrade_shared_lock_to_exclusive_lock()
    and MDL_context::release_ticket() methods to use MDL_map and
    MDL_lock::m_mutex instead of single LOCK_mdl mutex and wake up
    waiters according to the approach described above. The latter method
    also was renamed to MDL_context::release_lock().
  - Changed MDL_context::try_acquire_shared_lock()/exclusive_lock() and
    release_lock() not to handle global locks. They are now supposed to
    be taken explicitly like ordinary metadata locks.
  - Added helper MDL_context::try_acquire_global_intention_exclusive_lock()
    and acquire_global_intention_exclusive_lock() methods.
  - Moved common code from MDL_context::acquire_global_shared_lock() and
    acquire_global_intention_exclusive_lock() to new method -
    MDL_context::acquire_lock_impl().
  - Moved common code from MDL_context::try_acquire_shared_lock(),
    try_acquire_global_intention_exclusive_lock()/exclusive_lock()
    to MDL_context::try_acquire_lock_impl().
  - Since acquiring of several exclusive locks can no longer happen under
    single LOCK_mdl mutex the approach to it had to be changed. Now we do
    it in one by one fashion. This is done in alphabetical order to avoid
    deadlocks. Changed MDL_context::acquire_exclusive_locks() accordingly
    (as part of this change moved code responsible for acquiring single
    exclusive lock to new MDL_context::acquire_exclusive_lock_impl()
    method).
  - Since we no longer have single LOCK_mdl mutex which protects all
    MDL_context::m_is_waiting_in_mdl members using these members to
    determine if we have really awaken context holding conflicting
    shared lock became inconvinient. Got rid of this member and changed
    notify_shared_lock() helper function and process of acquiring
    of/upgrading to exclusive lock not to rely on such information.
    Now in MDL_context::acquire_exclusive_lock_impl() and
    MDL_ticket::upgrade_shared_lock_to_exclusive_lock() we simply
    re-try to wake up threads holding conflicting shared locks after
    small time out.
  - Adjusted MDL_context::can_wait_lead_to_deadlock() and
    MDL_ticket::has_pending_conflicting_lock() to use per-lock
    mutexes instead of LOCK_mdl. To do this introduced
    MDL_lock::has_pending_exclusive_lock() method.
sql/mdl.h:
  Changed metadata locking subsystem to use mutex per lock and condition
  variable per context instead of one mutex and one conditional variable
  for the whole subsystem. In order to implement this change:
  
  - Added MDL_key::cmp() method to be able to sort MDL_key objects
    alphabetically. Changed length fields in MDL_key class to uint16
    as 16-bit is enough for length of any key.
  - Changed MDL_ticket::get_ctx() to return pointer to non-const
    object in order to be able to use MDL_context::awake() method
    for such contexts.
  - Got rid of unlocked versions of can_wait_lead_to_deadlock()/
    has_pending_conflicting_lock() methods in MDL_context and
    MDL_ticket. We no longer has single mutex which protects all
    locks. Thus one always has to use versions of these methods
    which acquire per-lock mutexes.
  - MDL_request_list type of list now counts its elements.
  - Added MDL_context::m_ctx_wakeup_cond condition variable to be used
    for waiting until this context's pending request can be satisfied
    or its thread has to perform actions to resolve potential deadlock.
    Added awake() method to wake up context from such wait.
    Addition of condition variable made MDL_context uncopyable.
    As result we no longer can save/restore MDL_context when working
    with system tables. Instead we create MDL savepoint before opening
    those tables and rollback to it once they are closed.
  - MDL_context::release_ticket() became release_lock() method.
  - Added auxiliary MDL_context::acquire_exclusive_lock_impl() method
    which does all necessary work to acquire exclusive lock on one object
    but should not be used directly as it does not enforce any asserts
    ensuring that no deadlocks are possible.
  - Since we no longer need to know if thread trying to acquire exclusive
    lock managed to wake up any threads having conflicting shared locks
    (as, anyway, we will try to wake up such threads again shortly)
  - MDL_context::m_is_waiting_in_mdl member became unnecessary and
    notify_shared_lock() no longer needs to be friend of MDL_context.
  
  Changed approach to handling of global metadata locks. Instead of
  implicitly acquiring intention exclusive locks when user requests
  per-object upgradeable or exclusive locks now we require them to be
  acquired explicitly in the same way as ordinary metadata locks.
  
  - Added new GLOBAL namespace for such locks.
  - Added new type of lock to be requested MDL_INTENTION_EXCLISIVE.
  - Added MDL_context::try_acquire_global_intention_exclusive_lock()
    and acquire_global_intention_exclusive_lock() methods.
  - Moved common code from MDL_context::acquire_global_shared_lock()
    and acquire_global_intention_exclusive_lock() to new method -
    MDL_context::acquire_lock_impl().
  - Moved common code from MDL_context::try_acquire_shared_lock(),
    try_acquire_global_intention_exclusive_lock()/exclusive_lock()
    to MDL_context::try_acquire_lock_impl().
  - Added helper MDL_context::is_global_lock_owner() method to be
    able easily to find what kind of global lock this context holds.
  - MDL_context::m_has_global_shared_lock became unnecessary as
    global read lock is now represented by ordinary ticket.
  - Removed assert in MDL_context::set_lt_or_ha_sentinel() which became
    false for cases when we execute LOCK TABLES under global read lock
    mode.
sql/mysql_priv.h:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. To support this
  change methods of THD responsible for saving/restoring open table
  state were changed to use Open_tables_backup class which in addition
  to Open_table_state has a member for this savepoint. As result calls
  opening/closing system tables were changed to use Open_tables_backup
  instead of Open_table_state class as well.
sql/sp.cc:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. To support this
  change methods of THD responsible for saving/restoring open table
  state were changed to use Open_tables_backup class which in addition
  to Open_table_state has a member for this savepoint. As result code
  opening/closing system tables was changed to use Open_tables_backup
  instead of Open_table_state class as well.
sql/sp.h:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. To support this
  change methods of THD responsible for saving/restoring open table
  state were changed to use Open_tables_backup class which in addition
  to Open_table_state has a member for this savepoint. As result code
  opening/closing system tables was changed to use Open_tables_backup
  instead of Open_table_state class as well.
sql/sql_base.cc:
  close_thread_tables():
    Since we no longer use separate MDL_context for opening system
    tables we need to avoid releasing all transaction locks when
    closing system table. Releasing metadata lock on system table
    is now responsibility of THD::restore_backup_open_tables_state().
  open_table_get_mdl_lock(),
  Open_table_context::recover_from_failed_open():
    MDL subsystem no longer implicitly acquires global intention exclusive
    metadata lock when per-object upgradable or exclusive metadata lock is
    acquired. So this have to be done explicitly from these calls.
    Changed Open_table_context class to store MDL_request object for
    global intention exclusive lock acquired when opening tables.
  open_table():
    Do not release metadata lock if we have failed to open table as
    this lock might have been acquired by one of previous statements
    in transaction, and therefore should not be released.
  open_system_tables_for_read()/close_system_tables()/
  open_performance_schema_table():
    Instead of using separate MDL_context for opening system tables we now
    create MDL savepoint in the main context before opening such tables
    and rollback to this savepoint after closing them. To support this
    change methods of THD responsible for saving/restoring open table
    state were changed to use Open_tables_backup class which in addition
    to Open_table_state has a member for this savepoint. As result code
    opening/closing system tables was changed to use Open_tables_backup
    instead of Open_table_state class as well.
  close_performance_schema_table():
    Got rid of duplicated code.
sql/sql_class.cc:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. To support this
  change methods of THD responsible for saving/restoring open table
  state were changed to use Open_tables_backup class which in addition
  to Open_table_state has a member for this savepoint. Also releasing
  metadata lock on system table is now responsibility of
  THD::restore_backup_open_tables_state().
  Adjusted assert in THD::cleanup() to take into account fact that now
  we also use MDL sentinel for global read lock.
sql/sql_class.h:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. As result:
  - 'mdl_context' member was moved out of Open_tables_state to THD class.
    enter_locked_tables_mode()/leave_locked_tables_mode() had to follow.
  - Methods of THD responsible for saving/restoring open table state were
    changed to use Open_tables_backup class which in addition to
    Open_table_state has a member for this savepoint.
  Changed Open_table_context class to store MDL_request object for
  global intention exclusive lock acquired when opening tables.
sql/sql_delete.cc:
  MDL subsystem no longer implicitly acquires global intention exclusive
  metadata lock when per-object exclusive metadata lock is acquired.
  Now this has to be done by explicit calls outside of MDL subsystem.
sql/sql_help.cc:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. To support this
  change methods of THD responsible for saving/restoring open table
  state were changed to use Open_tables_backup class which in addition
  to Open_table_state has a member for this savepoint. As result code
  opening/closing system tables was changed to use Open_tables_backup
  instead of Open_table_state class as well.
sql/sql_parse.cc:
  Adjusted assert reload_acl_and_cache() to the fact that global read
  lock now takes full-blown metadata lock.
sql/sql_plist.h:
  Added support for element counting to I_P_List list template.
  One can use policy classes to specify if such counting is needed
  or not needed for particular list.
sql/sql_show.cc:
  Instead of using separate MDL_context for opening tables for I_S
  purposes we now create MDL savepoint in the main context before
  opening tables and rollback to this savepoint after closing them.
  To support this and similar change for system tables methods of
  THD responsible for saving/restoring open table state were changed
  to use Open_tables_backup class which in addition to Open_table_state
  has a member for this savepoint. As result code opening/closing tables
  for I_S purposes was changed to use Open_tables_backup instead of
  Open_table_state class as well.
sql/sql_table.cc:
  mysql_rm_tables_part2():
    Since now global intention exclusive metadata lock is ordinary
    metadata lock we no longer can rely that by releasing MDL locks
    on all tables we will release all locks acquired by this routine.
    So in non-LOCK-TABLES mode we have to release all locks acquired
    explicitly.
  prepare_for_repair(), mysql_alter_table():
    MDL subsystem no longer implicitly acquires global intention
    exclusive metadata lock when per-object exclusive metadata lock
    is acquired. Now this has to be done by explicit calls outside of
    MDL subsystem.
sql/tztime.cc:
  Instead of using separate MDL_context for opening system tables we now
  create MDL savepoint in the main context before opening such tables
  and rollback to this savepoint after closing them. To support this
  change methods of THD responsible for saving/restoring open table
  state were changed to use Open_tables_backup class which in addition
  to Open_table_state has a member for this savepoint. As result code
  opening/closing system tables was changed to use Open_tables_backup
  instead of Open_table_state class as well.
  Also changed code not to use special mechanism for open system tables
  when it is not really necessary.
 2010-01-21 23:43:03 +03:00
Konstantin Osipov
bf9c1b7353 Apply and review: 
3655 Jon Olav Hauglid   2009-10-19
Bug #30977 Concurrent statement using stored function and DROP FUNCTION 
           breaks SBR
Bug #48246 assert in close_thread_table

Implement a fix for:
Bug #41804 purge stored procedure cache causes mysterious hang for many
           minutes
Bug #49972 Crash in prepared statements

The problem was that concurrent execution of DML statements that
use stored functions and DDL statements that drop/modify the same
function might result in incorrect binary log in statement (and
mixed) mode and therefore break replication.

This patch fixes the problem by introducing metadata locking for
stored procedures and functions. This is similar to what is done
in Bug#25144 for views. Procedures and functions now are
locked using metadata locks until the transaction is either
committed or rolled back. This prevents other statements from
modifying the procedure/function while it is being executed. This
provides commit ordering - guaranteeing serializability across
multiple transactions and thus fixes the reported binlog problem.

Note that we do not take locks for top-level CALLs. This means
that procedures called directly are not protected from changes by
simultaneous DDL operations so they are executed at the state they
had at the time of the CALL. By not taking locks for top-level
CALLs, we still allow transactions to be started inside
procedures.

This patch also changes stored procedure cache invalidation.
Upon a change of cache version, we no longer invalidate the entire
cache, but only those routines which we use, only when a statement
is executed that uses them.

This patch also changes the logic of prepared statement validation.
A stored procedure used by a prepared statement is now validated
only once a metadata lock has been acquired. A version mismatch
causes a flush of the obsolete routine from the cache and
statement reprepare.
Incompatible changes:
1) ER_LOCK_DEADLOCK is reported for a transaction trying to access
   a procedure/function that is locked by a DDL operation in
   another connection.

2) Procedure/function DDL operations are now prohibited in LOCK
   TABLES mode as exclusive locks must be taken all at once and
   LOCK TABLES provides no way to specifiy procedures/functions to
   be locked.

Test cases have been added to sp-lock.test and rpl_sp.test.

Work on this bug has very much been a team effort and this patch
includes and is based on contributions from Davi Arnaut, Dmitry
Lenev, Magne Mæhre and Konstantin Osipov.


mysql-test/r/ps_ddl.result:
  Update results (Bug#30977).
mysql-test/r/ps_ddl1.result:
  Update results (Bug#30977).
mysql-test/r/sp-error.result:
  Update results (Bug#30977).
mysql-test/r/sp-lock.result:
  Update results (Bug#30977).
mysql-test/suite/rpl/r/rpl_sp.result:
  Update results (Bug#30977).
mysql-test/suite/rpl/t/rpl_sp.test:
  Add a test case for Bug#30977.
mysql-test/t/ps_ddl.test:
  Update comments. We no longer re-prepare a prepared statement
  when a stored procedure used in top-level CALL is changed.
mysql-test/t/ps_ddl1.test:
  Modifying stored procedure p1 no longer invalidates prepared
  statement "call p1" -- we can re-use the prepared statement
  without invalidation.
mysql-test/t/sp-error.test:
  Use a constant for an error value.
mysql-test/t/sp-lock.test:
  Add test coverage for Bug#30977.
sql/lock.cc:
  Implement lock_routine_name() - a way to acquire an 
  exclusive metadata lock (ex- name-lock) on 
  stored procedure/function.
sql/sp.cc:
  Change semantics of sp_cache_routine() -- now it has an option
  to make sure that the routine that is cached is up to date (has
  the latest sp cache version).
  
  Add sp_cache_invalidate() to sp_drop_routine(), where it was
  missing (a bug!).
  
  Acquire metadata locks for SP DDL (ALTER/CREATE/DROP). This is
  the core of the fix for Bug#30977.
  
  Since caching and cache invalidation scheme was changed, make 
  sure we don't invalidate the SP cache in the middle of a stored
  routine execution. At the same time, make sure we don't access
  stale data due to lack of invalidation. 
  For that, change ALTER FUNCTION/PROCEDURE to not use the cache,
  and SHOW PROCEDURE CODE/SHOW CREATE PROCEDURE/FUNCTION to always
  read an up to date version of the routine from the cache.
sql/sp.h:
  Add a helper wrapper around sp_cache_routine().
sql/sp_cache.cc:
  Implement new sp_cache_version() and sp_cache_flush_obsolete().
  Now we flush stale routines individually, rather than all at once.
sql/sp_cache.h:
  Update signatures of sp_cache_version() and sp_cache_flush_obsolete().
sql/sp_head.cc:
  Add a default initialization of sp_head::m_sp_cache_version.
  Remove a redundant sp_head::create().
sql/sp_head.h:
  Add m_sp_cache_version to sp_head class - we now 
  keep track of every routine in the stored procedure cache, rather than
  of the entire cache.
sql/sql_base.cc:
  Implement prelocking for stored routines. Validate stored
  routines after they were locked.
  Flush obsolete routines upon next access, one by one, not all at once
  (Bug#41804).
  Style fixes.
sql/sql_class.h:
  Rename a Open_table_context method.
sql/sql_parse.cc:
  Make sure stored procedures DDL commits the active transaction 
  (issues an implicit commit before and after).
  Remove sp_head::create(), a pure redundancy.
  Move the semantical check during alter routine inside sp_update_routine() code in order to:
  - avoid using SP cache during update, it may be obsolete.
  - speed up and simplify the update procedure.
  
  Remove sp_cache_flush_obsolete() calls, we no longer flush the entire
  cache, ever, stale routines are flushed before next use, one at a time.
sql/sql_prepare.cc:
  Move routine metadata validation to open_and_process_routine().
  Fix Bug#49972 (don't swap flags at reprepare).
  Reset Sroutine_hash_entries in reinit_stmt_before_use().
  Remove SP cache invalidation, it's now done by open_tables().
sql/sql_show.cc:
  Fix a warning: remove an unused label.
sql/sql_table.cc:
  Reset mdl_request.ticket for tickets acquired for routines inlined
  through a view, in CHECK TABLE statement, to satisfy an MDL assert.
sql/sql_update.cc:
  Move the cleanup of "translation items" to close_tables_for_reopen(),
  since it's needed in all cases when we back off, not just
  the back-off in multi-update. This fixes a bug when the server
  would crash on attempt to back off when opening tables
  for a statement that uses information_schema tables.
 2009-12-29 15:19:05 +03:00
Konstantin Osipov
dfdbc84585 A prerequisite patch for the fix for Bug#46224 
"HANDLER statements within a transaction might lead to deadlocks".
Introduce a notion of a sentinel to MDL_context. A sentinel
is a ticket that separates all tickets in the context into two
groups: before and after it. Currently we can have (and need) only
one designated sentinel -- it separates all locks taken by LOCK
TABLE or HANDLER statement, which must survive COMMIT and ROLLBACK
and all other locks, which must be released at COMMIT or ROLLBACK.
The tricky part is maintaining the sentinel up to date when
someone release its corresponding ticket. This can happen, e.g.
if someone issues DROP TABLE under LOCK TABLES (generally,
see all calls to release_all_locks_for_name()).
MDL_context::release_ticket() is modified to take care of it.

******
A fix and a test case for Bug#46224 "HANDLER statements within a
transaction might lead to deadlocks".

An attempt to mix HANDLER SQL statements, which are transaction-
agnostic, an open multi-statement transaction,
and DDL against the involved tables (in a concurrent connection) 
could lead to a deadlock. The deadlock would occur when
HANDLER OPEN or HANDLER READ would have to wait on a conflicting
metadata lock. If the connection that issued HANDLER statement
also had other metadata locks (say, acquired in scope of a 
transaction), a classical deadlock situation of mutual wait
could occur.

Incompatible change: entering LOCK TABLES mode automatically
closes all open HANDLERs in the current connection.

Incompatible change: previously an attempt to wait on a lock
in a connection that has an open HANDLER statement could wait
indefinitely/deadlock. After this patch, an error ER_LOCK_DEADLOCK
is produced.

The idea of the fix is to merge thd->handler_mdl_context
with the main mdl_context of the connection, used for transactional
locks. This makes deadlock detection possible, since all waits
with locks are "visible" and available to analysis in a single
MDL context of the connection.

Since HANDLER locks and transactional locks have a different life
cycle -- HANDLERs are explicitly open and closed, and so
are HANDLER locks, explicitly acquired and released, whereas
transactional locks "accumulate" till the end of a transaction
and are released only with COMMIT, ROLLBACK and ROLLBACK TO SAVEPOINT,
a concept of "sentinel" was introduced to MDL_context.
All locks, HANDLER and others, reside in the same linked list.
However, a selected element of the list separates locks with
different life cycle. HANDLER locks always reside at the
end of the list, after the sentinel. Transactional locks are
prepended to the beginning of the list, before the sentinel.
Thus, ROLLBACK, COMMIT or ROLLBACK TO SAVEPOINT, only
release those locks that reside before the sentinel. HANDLER locks
must be released explicitly as part of HANDLER CLOSE statement,
or an implicit close. 
The same approach with sentinel
is also employed for LOCK TABLES locks. Since HANDLER and LOCK TABLES
statement has never worked together, the implementation is
made simple and only maintains one sentinel, which is used either
for HANDLER locks, or for LOCK TABLES locks.


mysql-test/include/handler.inc:
  Add test coverage for Bug#46224 "HANDLER statements within a
  transaction might lead to deadlocks".
  Extended HANDLER coverage to cover a mix of HANDLER, transactions
  and DDL statements.
mysql-test/r/handler_innodb.result:
  Update results (Bug#46224).
mysql-test/r/handler_myisam.result:
  Update results (Bug#46224).
sql/lock.cc:
  Remove thd->some_tables_deleted, it's never used.
sql/log_event.cc:
  No need to check for thd->locked_tables_mode, 
  it's done inside release_transactional_locks().
sql/mdl.cc:
  Implement the concept of HANDLER and LOCK TABLES "sentinel".
  Implement a method to clone an acquired ticket.
  Do not return tickets beyond the sentinel when acquiring
  locks, create a copy.
  Remove methods to merge and backup MDL_context, they are now
  not used (Hurra!). This opens a path to a proper constructor
  and destructor of class MDL_context (to be done in a separate
  patch).
  Modify find_ticket() to provide information about where
  the ticket position is with regard to the sentinel.
sql/mdl.h:
  Add declarations necessary for the implementation of the concept
  of "sentinel", a dedicated ticket separating transactional and
  non-transactional locks.
sql/mysql_priv.h:
  Add mark_tmp_table_for_reuse() declaration, 
  a function to "close" a single session (temporary) table.
sql/sql_base.cc:
  Remove thd->some_tables_deleted.
  Modify deadlock-prevention asserts and deadlock detection
  heuristics to take into account that from now on HANDLER locks
  reside in the same locking context.
  Add broadcast_refresh() to mysql_notify_thread_having_shared_lock():
  this is necessary for the case when a thread having a shared lock
  is asleep in tdc_wait_for_old_versions(). This situation is only
  possible with HANDLER t1 OPEN; FLUSH TABLE (since all over code paths
  that lead to tdc_wait_for_old_versions() always have an
  empty MDL_context). Previously the server would simply deadlock
  in this situation.
sql/sql_class.cc:
  Remove now unused member "THD::some_tables_deleted". 
  Move mysql_ha_cleanup() a few lines above in THD::cleanup() 
  to make sure that all handlers are closed when it's time to 
  destroy the MDL_context of this connection.
  Remove handler_mdl_context and handler_tables.
sql/sql_class.h:
  Remove THD::handler_tables, THD::handler_mdl_context,
  THD::some_tables_deleted.
sql/sql_handler.cc:
  Remove thd->handler_tables.
  Remove thd->handler_mdl_context.
  Rewrite mysql_ha_open() to have no special provision for MERGE
  tables, now that we don't have to manipulate with thd->handler_tables
  it's easy to do.
  Remove dead code.
  Fix a bug in mysql_ha_flush() when we would always flush
  a temporary HANDLER when mysql_ha_flush() is called (actually
  mysql_ha_flush() never needs to flush temporary tables).
sql/sql_insert.cc:
  Update a comment, no more thd->some_tables_deleted.
sql/sql_parse.cc:
  Implement an incompatible change: entering LOCK TABLES closes
  active HANDLERs, if any.
  Now that we have a sentinel, we don't need to check
  for thd->locked_tables_mode when releasing metadata locks in
  COMMIT/ROLLBACK.
sql/sql_plist.h:
  Add new (now necessary) methods to the list class.
sql/sql_prepare.cc:
  Make sure we don't release HANDLER locks when rollback to a
  savepoint, set to not keep locks taken at PREPARE.
sql/sql_servers.cc:
  Update to a new signature of MDL_context::release_all_locks().
sql/sql_table.cc:
  Remove thd->some_tables_deleted.
sql/transaction.cc:
  Add comments. 
  Make sure rollback to (MDL) savepoint works under LOCK TABLES and
  with HANDLER tables.
 2009-12-22 19:09:15 +03:00
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
Marc Alff
0d99234dba Merge mysql-next-mr (revno 2942) --> mysql-next-mr-marc 2009-12-16 15:48:55 -07:00
Konstantin Osipov
391b5246fe Merge next-mr -> next-4284. 2009-12-15 22:59:07 +03:00
Alexander Nozdrin
aceea2342f Manual merge from mysql-trunk-merge. 
Conflicts:
  - extra/comp_err.c
  - mysql-test/collections/default.experimental
  - mysql-test/r/archive.result
  - mysql-test/r/select.result
  - mysql-test/suite/binlog/r/binlog_unsafe.result
  - mysql-test/suite/binlog/t/binlog_unsafe.test
  - mysql-test/suite/rpl/t/disabled.def
  - mysql-test/t/archive.test
  - mysql-test/t/select.test
  - sql/item.cc
  - sql/item.h
  - sql/item_timefunc.cc
  - sql/sql_base.cc
  - sql/sql_delete.cc
  - sql/sql_load.cc
  - sql/sql_partition.cc
  - sql/sql_table.cc
  - storage/innobase/handler/ha_innodb.cc
  - vio/vio.c
 2009-12-12 23:38:59 +03:00
Marc Alff
0531f85e16 Merge cleanup 2009-12-11 12:45:44 -07:00
Konstantin Osipov
42ed774073 Partial backport of: 
-----------------------------------------------------------
2497.392.1 Michael Widenius	2008-08-19
Fixes for Bug #38016 Maria: trying to access freed memory when
committing a transaction.
Don't write out states if they haven't changed.


sql/sql_table.cc:
  Call extra(HA_EXTRA_PREPARE_FOR_RENAME) before renaming a table.
 2009-12-11 14:12:47 +03:00
Alexander Nozdrin
5676713687 Manual merge from mysql-trunk. 
Conflicts:
  - client/mysqltest.cc
  - mysql-test/collections/default.experimental
  - mysql-test/suite/rpl/t/disabled.def
  - sql/mysqld.cc
  - sql/opt_range.cc
  - sql/sp.cc
  - sql/sql_acl.cc
  - sql/sql_partition.cc
  - sql/sql_table.cc
 2009-12-11 12:39:38 +03:00
Marc Alff
bea4ab9bb6 Merge mysql-next-mr (revno 2936) --> mysql-next-mr-marc 2009-12-11 01:58:13 -07:00
Alexander Nozdrin
97928f59b8 Auto-merge from mysql-next-mr. 2009-12-10 17:44:36 +03:00
Jon Olav Hauglid
fb6b5ee462 Backport of revno: 2617.68.37 
Bug #46654 False deadlock on concurrent DML/DDL with partitions, 
           inconsistent behavior

The problem was that if one connection is running a multi-statement 
transaction which involves a single partitioned table, and another 
connection attempts to alter the table, the first connection gets 
ER_LOCK_DEADLOCK and cannot proceed anymore, even when the ALTER TABLE 
statement in another connection has timed out or failed.

The reason for this was that the prepare phase for ALTER TABLE for 
partitioned tables removed all instances of the table from the table 
definition cache before it started waiting on the lock. The transaction 
running in the first connection would notice this and report ER_LOCK_DEADLOCK. 

This patch changes the prep_alter_part_table() ALTER TABLE code so that 
tdc_remove_table() is no longer called. Instead, only the TABLE instance
changed by prep_alter_part_table() is marked as needing reopen.

The patch also removes an unnecessary call to tdc_remove_table() from 
mysql_unpack_partition() as the changed TABLE object is destroyed by the 
caller at a later point.

Test case added in partition_sync.test.
 2009-12-10 14:26:00 +01:00
Jon Olav Hauglid
5e1dfa4c06 Backport of revno: 2617.71.1 
Bug#42546 Backup: RESTORE fails, thinking it finds an existing table

The problem occured when a MDL locking conflict happened for a non-existent 
table between a CREATE and a INSERT statement. The code for CREATE 
interpreted this lock conflict to mean that the table existed, 
which meant that the statement failed when it should not have.
The problem could occur for CREATE TABLE, CREATE TABLE LIKE and
ALTER TABLE RENAME.

This patch fixes the problem for CREATE TABLE and CREATE TABLE LIKE.
It is based on code backported from the mysql-6.1-fk tree written
by Dmitry Lenev. CREATE now uses normal open_and_lock_tables() code 
to acquire exclusive locks. This means that for the test case in the bug 
description, CREATE will wait until INSERT completes so that it can 
get the exclusive lock. This resolves the reported bug.

The patch also prohibits CREATE TABLE and CREATE TABLE LIKE under 
LOCK TABLES. Note that this is an incompatible change and must 
be reflected in the documentation. Affected test cases have been
updated.

mdl_sync.test contains tests for CREATE TABLE and CREATE TABLE LIKE.

Fixing the issue for ALTER TABLE RENAME is beyond the scope of this
patch. ALTER TABLE cannot be prohibited from working under LOCK TABLES
as this could seriously impact customers and a proper fix would require
a significant rewrite.
 2009-12-10 11:53:20 +01:00
Konstantin Osipov
f129367288 Merge with next-4284. 2009-12-10 11:41:03 +03:00
Konstantin Osipov
f26f632b44 Backport of: 
------------------------------------------------------------
revno: 2617.68.25
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-next-bg-pre2-2
timestamp: Wed 2009-09-16 18:26:50 +0400
message:
  Follow-up for one of pre-requisite patches for fixing bug #30977
  "Concurrent statement using stored function and DROP FUNCTION
  breaks SBR".

  Made enum_mdl_namespace enum part of MDL_key class and removed MDL_
  prefix from the names of enum members. In order to do the latter
  changed name of PROCEDURE symbol to PROCEDURE_SYM (otherwise macro
  which was automatically generated for this symbol conflicted with
  MDL_key::PROCEDURE enum member).
 2009-12-10 11:21:38 +03:00
Marc Alff
c082955f06 WL#2360 Performance schema 
Part III: mysys instrumentation
 2009-12-09 20:19:51 -07:00
Jon Olav Hauglid
f3e9b392ac Backport of revno: 2617.68.13 
Introduce a counter for protection against global read lock on thread level.

The functions for protection against global read lock sometimes need a local
variable to signal when the protection is set, and hence need to be released.
It would be better to control this behaviour via a counter on the THD struct,
telling how many times the protection has been claimed by the current thread.
A side-effect of the fix is that if protection is claimed twice for a thread,
only a simple increment is required for the second claim, instead of a
mutex-protected increment of the global variable protect_against_global_read_lock.


sql/lock.cc:
  Count how many times that we have claimed protection against global read lock.
  Assert that we really have the protection when releasing it.
  Added comments to all functions operating on global_read_lock.
sql/sql_class.cc:
  Added the counter variable global_read_lock_protection.
sql/sql_class.h:
  Added the counter variable global_read_lock_protection.
sql/sql_parse.cc:
  Replaced test on local variable need_start_waiting with test on
  thd->global_read_lock_protection.
sql/sql_table.cc:
  Replaced test on local variable need_start_waiting with test on
  thd->global_read_lock_protection.
sql/sql_trigger.cc:
  Inserted test on thd->global_read_lock_protection.
 2009-12-09 15:25:48 +01:00
Jon Olav Hauglid
334eb7e0af Backport of revno: 3702 
Bug #48248 assert in MDL_ticket::upgrade_shared_lock_to_exclusive

The assert would happen if REPAIR TABLE was used on a table already
locked by LOCK TABLES READ. REPAIR mistakenly tried to upgrade the
read-lock to exclusive, thereby triggering the assert.

The cause of the problem was that REPAIR TABLE ignored errors 
from opening and locking tables. This is by design, as REPAIR
can be used to broken tables that cannot be opened. However,
repair also ignored logical errors such as the inability to
exclusivly lock a table due to conflicting LOCK TABLES.

This patch fixes the problem by not ignoring errors from
opening and locking tables if inside LOCK TABLES mode.
In LOCK TABLES we already know that the table can be opened,
so that the failure to open must be a logical error.

Test added to repair.test.
 2009-12-09 14:03:37 +01:00
Jon Olav Hauglid
546e16ebd8 Backport of revno: 2617.69.40 
A pre-requisite patch for Bug#30977 "Concurrent statement using 
stored function and DROP FUNCTION breaks SBR".

This patch changes the MDL API by introducing a namespace for
lock keys: MDL_TABLE for tables and views and MDL_PROCEDURE
for stored procedures and functions. The latter is needed for
the fix for Bug#30977.
 2009-12-09 09:51:20 +01:00
Jon Olav Hauglid
4235167fcf Backport of revno: 2599.169.2 
Bug #42074 concurrent optimize table and 
           alter table = Assertion failed: thd->is_error()

This assertion could occur if OPTIMIZE TABLE was started on a InnoDB table
and the table was altered to different storage engine after OPTIMIZE
had started. This allowed OPTIMIZE to pass the initial checks for 
storage engine support, but fail once it reached "recreate+analyze"
if this operation was not supported by the new storage engine.
The bug had no consequences for non-debug builds of the server.

In detail, the assertion was triggered when ha_analyze() returned 
HA_ADMIN_NOT_IMPLEMENTED. This led to a code path which included an 
assert checking for diagnostics area contents. Since this area had 
not been filled, the assertion was triggered. The diagnostics area 
is in this case only used to provide more detailed information about 
why optimize failed. The triggered code path sends this information 
to the client and clears the diagnostic area.

This patch fixed the problem by adding an error message to the diagnostic 
area if ha_analyze() fails. This error message contains the error code
returned by ha_analyze().

Test case added to innodb_mysql_sync.test.
 2009-12-09 09:32:29 +01:00
Konstantin Osipov
302352723e Backport of: 
----------------------------------------------------------
revno: 2617.69.24
committer: Konstantin Osipov <kostja@sun.com>
branch nick: 5.4-42546
timestamp: Fri 2009-08-14 19:22:05 +0400
message:
  A pre-requisite for a fix for Bug#42546 "Backup: RESTORE fails, thinking it
  finds an existing table"
  Back-port from WL 148 "Foreign keys" feature tree a patch
  that introduced Prelocking_strategy class -- a way to parameterize
  open_tables() behaviour, implemented by Dmitry Lenev.

(Part of WL#4284).

sql/sql_base.cc:
  Implement different prelocking strategies. Use an instance of
  prelocking_strategy in open_tables().
sql/sql_class.h:
  Add declarations for class Prelocking_strategy.
sql/sql_lex.h:
  Add a helper method to access last table of the global table list
  (lex->query_tables).
sql/sql_parse.cc:
  Use a special prelocking strategy when locking tables for LOCK TABLES.
sql/sql_table.cc:
  Use normal open_and_lock_tables_derived() in ALTER TABLE.
sql/sql_yacc.yy:
  Modify the grammar to not pollute the global table list with tables
  that should not be opened.
 2009-12-08 17:13:12 +03:00
Konstantin Osipov
ce5c87a3d3 Backport of: 
----------------------------------------------------------
revno: 2617.69.20
committer: Konstantin Osipov <kostja@sun.com>
branch nick: 5.4-4284-1-assert
timestamp: Thu 2009-08-13 18:29:55 +0400
message:
  WL#4284 "Transactional DDL locking"
  A review fix.
  Since WL#4284 implementation separated MDL_request and MDL_ticket,
  MDL_request becamse a utility object necessary only to get a ticket.
  Store it by-value in TABLE_LIST with the intent to merge
  MDL_request::key with table_list->table_name and table_list->db
  in future.
  Change the MDL subsystem to not require MDL_requests to
  stay around till close_thread_tables().
  Remove the list of requests from the MDL context.
  Requests for shared metadata locks acquired in open_tables()
  are only used as a list in recover_from_failed_open_table_attempt(),
  which calls mdl_context.wait_for_locks() for this list.
  To keep such list for recover_from_failed_open_table_attempt(),
  introduce a context class (Open_table_context), that collects
  all requests.
  A lot of minor cleanups and simplications that became possible
  with this change.


sql/event_db_repository.cc:
  Remove alloc_mdl_requests(). Now MDL_request instance is a member
  of TABLE_LIST, and init_one_table() initializes it.
sql/ha_ndbcluster_binlog.cc:
  Remove now unnecessary declaration and initialization
  of binlog_mdl_request.
sql/lock.cc:
  No need to allocate MDL requests in lock_table_names() now.
sql/log.cc:
  Use init_one_table() method, remove alloc_mdl_requests(),
  which is now unnecessary.
sql/log_event.cc:
  No need to allocate mdl_request separately now.
  Use init_one_table() method.
sql/log_event_old.cc:
  Update to the new signature of close_tables_for_reopen().
sql/mdl.cc:
  Update try_acquire_exclusive_lock() to be more easy to use.
  Function lock_table_name_if_not_cached() has been removed.
  Make acquire_shared_lock() signature consistent with
  try_acquire_exclusive_lock() signature.
  Remove methods that are no longer used.
  Update comments.
sql/mdl.h:
  Implement an assignment operator that doesn't
  copy MDL_key (MDL_key::operator= is private and
  should remain private).
  This is a hack to work-around assignment of TABLE_LIST
  by value in several places. Such assignments violate
  encapsulation, since only perform a shallow copy.
  In most cases these assignments are a hack on their own.
sql/mysql_priv.h:
  Update signatures of close_thread_tables() and close_tables_for_reopen().
sql/sp.cc:
  Allocate TABLE_LIST in thd->mem_root.
  Use init_one_table().
sql/sp_head.cc:
  Use init_one_table().
  Remove thd->locked_tables_root, it's no longer needed.
sql/sql_acl.cc:
  Use init_mdl_requests() and init_one_table().
sql/sql_base.cc:
  Update to new signatures of try_acquire_shared_lock() and
  try_acquire_exclusive_lock().
  Remove lock_table_name_if_not_cached().
  Fix a bug in open_ltable() that would not return ER_LOCK_DEADLOCK
  in case of a failed lock_tables() and a multi-statement
  transaction.
  Fix a bug in open_and_lock_tables_derived() that would
  not return ER_LOCK_DEADLOCK in case of a multi-statement
  transaction and a failure of lock_tables().
  Move assignment of enum_open_table_action to a method of Open_table_context, a new class that maintains information
  for backoff actions.
  Minor rearrangements of the code.
  Remove alloc_mdl_requests() in functions that work with system
  tables: instead the patch ensures that callers always initialize
  TABLE_LIST argument.
sql/sql_class.cc:
  THD::locked_tables_root is no more.
sql/sql_class.h:
  THD::locked_tables_root is no more.
  Add a declaration for Open_table_context class.
sql/sql_delete.cc:
  Update to use the simplified MDL API.
sql/sql_handler.cc:
  TABLE_LIST::mdl_request is stored by-value now.
  Ensure that mdl_request.ticket is NULL for every request
  that is passed into MDL, to satisfy MDL asserts.
  @ sql/sql_help.cc
  Function open_system_tables_for_read() no longer initializes
  mdl_requests.
  Move TABLE_LIST::mdl_request initialization closer to
  TABLE_LIST initialization.
sql/sql_help.cc:
  Function open_system_tables_for_read() no longer initializes
  mdl_requests.
  Move TABLE_LIST::mdl_request initialization closer to
  TABLE_LIST initialization.
sql/sql_insert.cc:
  Remove assignment by-value of TABLE_LIST in
  TABLEOP_HOOKS. We can't carry over a granted
  MDL ticket from one table list to another.
sql/sql_parse.cc:
  Change alloc_mdl_requests() -> init_mdl_requests().
  @todo We can remove init_mdl_requests() altogether
  in some places: all places that call add_table_to_list()
  already have mdl requests initialized.
sql/sql_plugin.cc:
  Use init_one_table().
  THD::locked_tables_root is no more.
sql/sql_servers.cc:
  Use init_one_table().
sql/sql_show.cc:
  Update acquire_high_priority_shared_lock() to use
  TABLE_LIST::mdl_request rather than allocate an own.
  Fix get_trigger_table_impl() to use init_one_table(),
  check for out of memory, follow the coding style.
sql/sql_table.cc:
  Update to work with TABLE_LIST::mdl_request by-value.
  Remove lock_table_name_if_not_cached().
  The code that used to delegate to it is quite simple and
  concise without it now.
sql/sql_udf.cc:
  Use init_one_table().
sql/sql_update.cc:
  Update to use the new signature of close_tables_for_reopen().
sql/table.cc:
  Move re-setting of mdl_requests for prepared statements
  and stored procedures from close_thread_tables() to
  reinit_stmt_before_use().
  Change alloc_mdl_requests() to init_mdl_requests().
  init_mdl_requests() is a hack that can't be deleted
  until we don't have a list-aware TABLE_LIST constructor.
  Hopefully its use will be minimal
sql/table.h:
  Change alloc_mdl_requests() to init_mdl_requests()
  TABLE_LIST::mdl_request is stored by value.
sql/tztime.cc:
  We no longer initialize mdl requests in open_system_tables_for*()
  functions. Move this initialization closer to initialization
  of the rest of TABLE_LIST members.
storage/myisammrg/ha_myisammrg.cc:
  Simplify mdl_request initialization.
 2009-12-08 12:57:07 +03:00
Konstantin Osipov
478e09609c Backport of: 
----------------------------------------------------------
revno: 2617.69.2
committer: Konstantin Osipov <kostja@sun.com>
branch nick: 5.4-azalea-bugfixing
timestamp: Mon 2009-08-03 19:26:04 +0400
message:
  A fix and a test case for Bug#45035 "Altering table under LOCK TABLES
  results in "Error 1213 Deadlock found...".

  If a user had a table locked with LOCK TABLES
  for READ and for WRITE in the same connection, ALTER TABLE
  could fail.

  Root cause analysis:

  If a connection issues

  LOCK TABLE t1 write, t1 a read, t1 b read;

  the new LOCK TABLES code in 6.0 (part of WL 3726) will create
  the following list of TABLE_LIST objects
  (thd->locked_tables_list->m_locked_tables):

  {"t1" "b" tl_read_no_insert}, {"t1" "a" tl_read_no_insert},
  {"t1" "t1" tl_write }

  Later on, when we try to ALTER table t1, mysql_alter_table()
  closes all TABLE instances and releases its thr_lock locks,
  keeping only an exclusive metadata lock on t1.

  But when ALTER is finished, Locked_table_list::reopen_tables()
  tries to restore the original list of open and locked tables.

  Before this patch, it used to do so one by one:
  Open t1 b, get TL_READ_NO_INSERT lock,
  Open t1 a, get TL_READ_NO_INSERT lock
  Open t1, try to get TL_WRITE lock, deadlock.

  The cause of the deadlock is that thr_lock.c doesn't
  resolve the situation when the read list only consists
  of locks taken by the same thread, followed by this very
  thread trying to take a WRITE lock. Indeed, since
  thr_lock_multi always gets a sorted list of locks,
  WRITE locks always precede READ locks in the list
  to lock.

  Don't try to fix thr_lock.c deficiency, keep this
  code simple.
  Instead, try to take all thr_lock locks at once
  in ::reopen_tables().


mysql-test/r/lock.result:
  Update results: test case for Bug#45035.
mysql-test/t/lock.test:
  Add a test case for Bug#45035.
sql/sql_base.cc:
  Take all thr_lock locks at once in Locked_tables_list::reopen_tables().
sql/sql_class.h:
  Add a helper array to store tables for mysql_lock_tables()
  in reopen_tables().
sql/sql_table.cc:
  Update unlink_all_closed_tables() to the new signature.
 2009-12-08 11:38:45 +03:00
Konstantin Osipov
a14bbee5ab Backport of revno ## 2617.31.1, 2617.31.3, 2617.31.4, 2617.31.5, 
2617.31.12, 2617.31.15, 2617.31.15, 2617.31.16, 2617.43.1
- initial changeset that introduced the fix for 
Bug#989 and follow up fixes for all test suite failures
introduced in the initial changeset. 
------------------------------------------------------------
revno: 2617.31.1
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Fri 2009-03-06 19:17:00 -0300
message:
Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order
WL#4284: Transactional DDL locking

Currently the MySQL server does not keep metadata locks on
schema objects for the duration of a transaction, thus failing
to guarantee the integrity of the schema objects being used
during the transaction and to protect then from concurrent
DDL operations. This also poses a problem for replication as
a DDL operation might be replicated even thought there are
active transactions using the object being modified.

The solution is to defer the release of metadata locks until
a active transaction is either committed or rolled back. This
prevents other statements from modifying the table for the
entire duration of the transaction. This provides commitment
ordering for guaranteeing serializability across multiple
transactions.

- Incompatible change:

If MySQL's metadata locking system encounters a lock conflict,
the usual schema is to use the try and back-off technique to
avoid deadlocks -- this schema consists in releasing all locks
and trying to acquire them all in one go.

But in a transactional context this algorithm can't be utilized
as its not possible to release locks acquired during the course
of the transaction without breaking the transaction commitments.
To avoid deadlocks in this case, the ER_LOCK_DEADLOCK will be
returned if a lock conflict is encountered during a transaction.

Let's consider an example:

A transaction has two statements that modify table t1, then table
t2, and then commits. The first statement of the transaction will
acquire a shared metadata lock on table t1, and it will be kept
utill COMMIT to ensure serializability.

At the moment when the second statement attempts to acquire a
shared metadata lock on t2, a concurrent ALTER or DROP statement
might have locked t2 exclusively. The prescription of the current
locking protocol is that the acquirer of the shared lock backs off
-- gives up all his current locks and retries. This implies that
the entire multi-statement transaction has to be rolled back.

- Incompatible change:

FLUSH commands such as FLUSH PRIVILEGES and FLUSH TABLES WITH READ
LOCK won't cause locked tables to be implicitly unlocked anymore.


mysql-test/extra/binlog_tests/drop_table.test:
  Add test case for Bug#989.
mysql-test/extra/binlog_tests/mix_innodb_myisam_binlog.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/include/mix1.inc:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/include/mix2.inc:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/r/flush_block_commit.result:
  Update test case result (WL#4284).
mysql-test/r/flush_block_commit_notembedded.result:
  Update test case result (WL#4284).
mysql-test/r/innodb.result:
  Update test case result (WL#4284).
mysql-test/r/innodb_mysql.result:
  Update test case result (WL#4284).
mysql-test/r/lock.result:
  Add test case result for an effect of WL#4284/Bug#989
  (all locks should be released when a connection terminates).
mysql-test/r/mix2_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/r/not_embedded_server.result:
  Update test case result (effects of WL#4284/Bug#989).
  Add a test case for interaction of WL#4284 and FLUSH PRIVILEGES.
mysql-test/r/partition_innodb_semi_consistent.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/r/partition_sync.result:
  Temporarily disable the test case for Bug#43867,
  which will be fixed by a subsequent backport.
mysql-test/r/ps.result:
  Add a test case for effect of PREPARE on transactional
  locks: we take a savepoint at beginning of PREAPRE
  and release it at the end. Thus PREPARE does not 
  accumulate metadata locks (Bug#989/WL#4284).
mysql-test/r/read_only_innodb.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_row_drop_tbl.result:
  Add a test case result (WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_row_mix_innodb_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_stm_drop_tbl.result:
  Add a test case result (WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_unsafe.result:
  A side effect of Bug#989 -- slightly different table map ids.
mysql-test/suite/binlog/t/binlog_row_drop_tbl.test:
  Add a test case for WL#4284/Bug#989.
mysql-test/suite/binlog/t/binlog_stm_drop_tbl.test:
  Add a test case for WL#4284/Bug#989.
mysql-test/suite/binlog/t/binlog_stm_row.test:
  Update to the new state name. This
  is actually a follow up to another patch for WL#4284, 
  that changes Locked thread state to Table lock.
mysql-test/suite/ndb/r/ndb_index_ordered.result:
  Remove result for disabled part of the test case.
mysql-test/suite/ndb/t/disabled.def:
  Temporarily disable a test case (Bug#45621).
mysql-test/suite/ndb/t/ndb_index_ordered.test:
  Disable a part of a test case (needs update to
  reflect semantics of Bug#989).
mysql-test/suite/rpl/t/disabled.def:
  Disable tests made meaningless by transactional metadata
  locking.
mysql-test/suite/sys_vars/r/autocommit_func.result:
  Add a commit (Bug#989).
mysql-test/suite/sys_vars/t/autocommit_func.test:
  Add a commit (Bug#989).
mysql-test/t/flush_block_commit.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/t/flush_block_commit_notembedded.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
  Add a test case for transaction-scope locks and the global
  read lock (Bug#989/WL#4284).
mysql-test/t/innodb.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction
  (effects of Bug#989/WL#4284).
mysql-test/t/lock.test:
  Add a test case for Bug#989/WL#4284.
mysql-test/t/not_embedded_server.test:
  Add a test case for Bug#989/WL#4284.
mysql-test/t/partition_innodb_semi_consistent.test:
  Replace TRUNCATE with DELETE, to not issue
  an implicit commit of a transaction, and not depend
  on metadata locks.
mysql-test/t/partition_sync.test:
  Temporarily disable the test case for Bug#43867,
  which needs a fix to be backported from 6.0.
mysql-test/t/ps.test:
  Add a test case for semantics of PREPARE and transaction-scope
  locks: metadata locks on tables used in PREPARE are enclosed into a
  temporary savepoint, taken at the beginning of PREPARE,
  and released at the end. Thus PREPARE does not effect
  what locks a transaction owns.
mysql-test/t/read_only_innodb.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction 
  (Bug#989/WL#4284).
  
  Wait for the read_only statement to actually flush tables before
  sending other concurrent statements that depend on its state.
mysql-test/t/xa.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction 
  (Bug#989/WL#4284).
sql/ha_ndbcluster_binlog.cc:
  Backport bits of changes of ha_ndbcluster_binlog.cc
  from 6.0, to fix the failing binlog test suite with
  WL#4284. WL#4284 implementation does not work
  with 5.1 implementation of ndbcluster binlog index.
sql/log_event.cc:
  Release metadata locks after issuing a commit.
sql/mdl.cc:
  Style changes (WL#4284).
sql/mysql_priv.h:
  Rename parameter to match the name used in the definition (WL#4284).
sql/rpl_injector.cc:
  Release metadata locks on commit (WL#4284).
sql/rpl_rli.cc:
  Remove assert made meaningless, metadata locks are released
  at the end of the transaction.
sql/set_var.cc:
  Close tables and release locks if autocommit mode is set.
sql/slave.cc:
  Release metadata locks after a rollback.
sql/sql_acl.cc:
  Don't implicitly unlock locked tables. Issue a implicit commit
  at the end and unlock tables.
sql/sql_base.cc:
  Defer the release of metadata locks when closing tables
  if not required to.
  Issue a deadlock error if the locking protocol requires
  that a transaction re-acquire its locks.
  
  Release metadata locks when closing tables for reopen.
sql/sql_class.cc:
  Release metadata locks if the thread is killed.
sql/sql_parse.cc:
  Release metadata locks after implicitly committing a active
  transaction, or after explicit commits or rollbacks.
sql/sql_plugin.cc:
  
  Allocate MDL request on the stack as the use of the table
  is contained within the function. It will be removed from
  the context once close_thread_tables is called at the end
  of the function.
sql/sql_prepare.cc:
  The problem is that the prepare phase of the CREATE TABLE
  statement takes a exclusive metadata lock lock and this can
  cause a self-deadlock the thread already holds a shared lock
  on the table being that should be created.
  
  The solution is to make the prepare phase take a shared
  metadata lock when preparing a CREATE TABLE statement. The
  execution of the statement will still acquire a exclusive
  lock, but won't cause any problem as it issues a implicit
  commit.
  
  After some discussions with stakeholders it has been decided that
  metadata locks acquired during a PREPARE statement must be released
  once the statement is prepared even if it is prepared within a multi
  statement transaction.
sql/sql_servers.cc:
  Don't implicitly unlock locked tables. Issue a implicit commit
  at the end and unlock tables.
sql/sql_table.cc:
  Close table and release metadata locks after a admin operation.
sql/table.h:
  The problem is that the prepare phase of the CREATE TABLE
  statement takes a exclusive metadata lock lock and this can
  cause a self-deadlock the thread already holds a shared lock
  on the table being that should be created.
  
  The solution is to make the prepare phase take a shared
  metadata lock when preparing a CREATE TABLE statement. The
  execution of the statement will still acquire a exclusive
  lock, but won't cause any problem as it issues a implicit
  commit.
sql/transaction.cc:
  Release metadata locks after the implicitly committed due
  to a new transaction being started. Also, release metadata
  locks acquired after a savepoint if the transaction is rolled
  back to the save point.
  
  The problem is that in some cases transaction-long metadata locks
  could be released before the transaction was committed. This could
  happen when a active transaction was ended by a "START TRANSACTION"
  or "BEGIN" statement, in which case the metadata locks would be
  released before the actual commit of the active transaction.
  
  The solution is to defer the release of metadata locks to after the
  transaction has been implicitly committed. No test case is provided
  as the effort to provide one is too disproportional to the size of
  the fix.
 2009-12-05 02:02:48 +03:00
Konstantin Osipov
a9013f8fba Backport of: 
----------------------------------------------------------
revno: 2617.23.20
committer: Konstantin Osipov <kostja@sun.com>
branch nick: mysql-6.0-runtime
timestamp: Wed 2009-03-04 16:31:31 +0300
message:
  WL#4284 "Transactional DDL locking"
  Review comments: "Objectify" the MDL API.
  MDL_request and MDL_context still need manual construction and
  destruction, since they are used in environment that is averse
  to constructors/destructors.


sql/mdl.cc:
  Improve comments.
  Add asserts to backup()/restore_from_backup()/merge() methods.
  Fix an order bug in the error path of mdl_acquire_exclusive_locks():
  we used to first free a ticket object, and only then exclude
  it from the list of tickets.
 2009-12-04 02:52:05 +03:00
Konstantin Osipov
f477e66ec5 Backport of: 
------------------------------------------------------------
revno: 2617.23.18
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Mon 2009-03-02 18:18:26 -0300
message:
Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order
WL#4284: Transactional DDL locking

This is a prerequisite patch:

These changes are intended to split lock requests from granted
locks and to allow the memory and lifetime of granted locks to
be managed within the MDL subsystem. Furthermore, tickets can
now be shared and therefore are used to satisfy multiple lock
requests, but only shared locks can be recursive.

The problem is that the MDL subsystem morphs lock requests into
granted locks locks but does not manage the memory and lifetime
of lock requests, and hence, does not manage the memory of
granted locks either. This can be problematic because it puts the
burden of tracking references on the users of the subsystem and
it can't be easily done in transactional contexts where the locks
have to be kept around for the duration of a transaction.

Another issue is that recursive locks (when the context trying to
acquire a lock already holds a lock on the same object) requires
that each time the lock is granted, a unique lock request/granted
lock structure structure must be kept around until the lock is
released. This can lead to memory leaks in transactional contexts
as locks taken during the transaction should only be released at
the end of the transaction. This also leads to unnecessary wake
ups (broadcasts) in the MDL subsystem if the context still holds
a equivalent of the lock being released.

These issues are exacerbated due to the fact that WL#4284 low-level
design says that the implementation should "2) Store metadata locks
in transaction memory root, rather than statement memory root" but
this is not possible because a memory root, as implemented in mysys,
requires all objects allocated from it to be freed all at once.

This patch combines review input and significant code contributions
from Konstantin Osipov (kostja) and Dmitri Lenev (dlenev).


mysql-test/r/mdl_sync.result:
  Add test case result.
mysql-test/t/mdl_sync.test:
  Add test case for shared lock upgrade case.
sql/event_db_repository.cc:
  Rename mdl_alloc_lock to mdl_request_alloc.
sql/ha_ndbcluster_binlog.cc:
  Use new function names to initialize MDL lock requests.
sql/lock.cc:
  Rename MDL functions.
sql/log_event.cc:
  The MDL request now holds the table and database name data (MDL_KEY).
sql/mdl.cc:
  Move the MDL key to the MDL_LOCK structure in order to make the
  object suitable for allocation from a fixed-size allocator. This
  allows the simplification of the lists in the MDL_LOCK object,
  which now are just two, one for granted tickets and other for
  waiting (upgraders) tickets.
  
  Recursive requests for a shared lock on the same object can now
  be granted using the same lock ticket. This schema is only used
  for shared locks because that the only case that matters. This
  is used to avoid waste of resources in case a context (connection)
  already holds a shared lock on a object.
sql/mdl.h:
  Introduce a metadata lock object key which is used  to uniquely
  identify lock objects.
  
  Separate the structure used to represent pending lock requests
  from the structure used to represent granted metadata locks.
  
  Rename functions used to manipulate locks requests in order to
  have a more consistent function naming schema.
sql/sp_head.cc:
  Rename mdl_alloc_lock to mdl_request_alloc.
sql/sql_acl.cc:
  Rename alloc_mdl_locks to alloc_mdl_requests.
sql/sql_base.cc:
  Various changes to accommodate that lock requests are separated
  from lock tickets (granted locks).
sql/sql_class.h:
  Last acquired lock before the savepoint was set.
sql/sql_delete.cc:
  Various changes to accommodate that lock requests are separated
  from lock tickets (granted locks).
sql/sql_handler.cc:
  Various changes to accommodate that lock requests are separated
  from lock tickets (granted locks).
sql/sql_insert.cc:
  Rename alloc_mdl_locks to alloc_mdl_requests.
sql/sql_parse.cc:
  Rename alloc_mdl_locks to alloc_mdl_requests.
sql/sql_plist.h:
  Typedef for iterator type.
sql/sql_plugin.cc:
  Rename alloc_mdl_locks to alloc_mdl_requests.
sql/sql_servers.cc:
  Rename alloc_mdl_locks to alloc_mdl_requests.
sql/sql_show.cc:
  Various changes to accommodate that lock requests are separated
  from lock tickets (granted locks).
sql/sql_table.cc:
  Various changes to accommodate that lock requests are separated
  from lock tickets (granted locks).
sql/sql_trigger.cc:
  Save reference to the lock ticket so it can be downgraded later.
sql/sql_udf.cc:
  Rename alloc_mdl_locks to alloc_mdl_requests.
sql/table.cc:
  Rename mdl_alloc_lock to mdl_request_alloc.
sql/table.h:
  Separate MDL lock requests from lock tickets (granted locks).
storage/myisammrg/ha_myisammrg.cc:
  Rename alloc_mdl_locks to alloc_mdl_requests.
 2009-12-04 02:29:40 +03:00
Konstantin Osipov
c52d4830bf Backport of: 
------------------------------------------------------------
revno: 2630.22.3
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Thu 2008-08-07 22:33:43 -0300
message:
WL#4284: Transactional DDL locking

Make transaction management more modular through a new interface.

The overall objective of this change is to provide groundwork
for the design of transactional DDL locking by cleaning up the
transaction high level API to better distinguish operations implicit
and explicit, and single statement transaction from operations on
the normal transaction.

Having a a high-level interface for transaction management provides
a better base for implementing transactional concepts that are not
always tied to storage engines and also makes it easier to interect
with other higher level modules of the server.

client/Makefile.am:
  Add new file to the build.
libmysqld/CMakeLists.txt:
  Add new file to the build.
libmysqld/Makefile.am:
  Add new file to the build.
sql/CMakeLists.txt:
  Add new file to the build.
sql/Makefile.am:
  Add new file to the build.
sql/handler.cc:
  Remove multiplexer commit or rollback function. Most callers already
  have enough information to decided whether to rollback or commit.
  Having plain and well named functions makes it easier to read
  and understand code.
sql/handler.h:
  Remove wrapper function as the low level transaction functions
  shouldn't be called directly anymore.
sql/log_event.cc:
  Rename transaction management functions to the new names.
sql/log_event_old.cc:
  Rename transaction management functions to the new names.
sql/mysql_priv.h:
  Remove obsolete functions for implicit and explicit commit.
sql/rpl_injector.cc:
  Rename transaction management functions to the new names.
sql/rpl_rli.cc:
  Rename transaction management functions to the new names.
sql/set_var.cc:
  Rename transaction management functions to the new names.
sql/slave.cc:
  Rename transaction management functions to the new names.
sql/sql_base.cc:
  Rename transaction management functions to the new names.
sql/sql_class.cc:
  Rename transaction management functions to the new names.
sql/sql_delete.cc:
  Rename transaction management functions to the new names.
sql/sql_do.cc:
  Rename transaction management functions to the new names.
sql/sql_insert.cc:
  Rename transaction management functions to the new names.
sql/sql_parse.cc:
  Rename transaction management functions to the new names.
sql/sql_partition.cc:
  Rename transaction management functions to the new names.
sql/sql_table.cc:
  Rename transaction management functions to the new names.
sql/transaction.cc:
  Implement wrapper functions to differentiate operations on
  the single statement transaction from the ones operating
  on the normal transaction.
sql/transaction.h:
  Export new functions for dealing with transaction commands.
 2009-12-03 21:37:38 +03:00
Konstantin Osipov
3543d2556d Backport of: 
------------------------------------------------------------
revno: 2630.13.16
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: WL#4284
timestamp: Sat 2008-07-26 13:38:20 -0300
message:
WL#4284: Transactional DDL locking

SQL statements' effect on transactions.

Currently the MySQL server and its storage engines are not
capable of rolling back operations that define or modify data
structures (also known as DDL statements) or operations that
alter any of the system tables (the mysql database). Allowing
these group of statements to participate in transactions
is unfeasible at this time (since rollback has no effect
whatsoever on them) and goes against the design of our metadata
locking subsystem.

The solution is to issue implicit commits before and after
those statements execution. This effectively confines each of
those statements to its own special transaction and ensures
that metadata locks taken during this special transaction
are not leaked into posterior statements/transactions.


mysql-test/include/commit.inc:
  Alter table rename was not committing the normal transaction at the
  end of its execution, and as a consequence, the commit was being
  issued in the next DDL command (rename table) that happened to end
  the active transaction. Other changes are to take into account the
  implicit commits issued before and after the DDL command execution.
mysql-test/include/implicit_commit_helper.inc:
  Add auxiliary test that shows if a statement issued a 
  implicit commit.
mysql-test/r/commit_1innodb.result:
  
  Update test case result.
mysql-test/r/implicit_commit.result:
  Test implicit commit behavior of some SQL commands.
mysql-test/t/implicit_commit.test:
  Test implicit commit behavior of some SQL commands.
sql/events.cc:
  Transaction is now ended before the command execution.
sql/mysql_priv.h:
  Add flags array for server commands and remove historical 
  left over.
sql/sql_class.h:
  Add flags to control when to issue implicit commits before and
  after a command execution.
sql/sql_delete.cc:
  A implicit commit is issued at the end of truncate
  statements.
sql/sql_parse.cc:
  Mark commands that need implicit commits before and
  after their executions. The implicit commits of the
  statement and the normal transaction are now issued
  regardless of the user access privileges.
sql/sql_table.cc:
  A implicit commit is now issued before admin commands.
tests/mysql_client_test.c:
  Test that COM_REFRESH issues a implicit commit.
 2009-12-03 18:47:20 +03:00
Konstantin Osipov
c659143c1e Merge next-mr -> next-4284 2009-12-03 14:37:42 +03:00
Konstantin Osipov
94f25504a3 Merge next-mr -> next-mr-runtime 2009-12-03 14:01:04 +03:00
Konstantin Osipov
7f628ac2dd Backport of: 
----------------------------------------------------------
revno: 2630.4.38
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-4144
timestamp: Wed 2008-06-25 22:07:06 +0400
message:
  WL#4144 - Lock MERGE engine children.
  Committing a version of the patch merged with WL#3726
  on behalf of Ingo.

  Step #1: Move locking from parent to children.

  MERGE children are now left in the query list of tables
  after inserted there in open_tables(). So they are locked
  by lock_tables() as all other tables are.

  The MERGE parent does not store locks any more. It appears
  in a MYSQL_LOCK with zero lock data. This is kind of a "dummy"
  lock.

  All other lock handling is also done directly on the children.
  To protect against parent or child modifications during LOCK
  TABLES, the children are detached after every statement and
  attached before every statement, even under LOCK TABLES.

  The children table list is removed from the query list of tables
  on every detach and on close of the parent.

  Step #2: Move MERGE specific functionality from SQL layer
  into table handler.

  Functionality moved from SQL layer (mainly sql_base.cc)
  to the table handler (ha_myisammrg.cc).

  Unnecessary code is removed from the SQL layer.

  Step #3: Moved all MERGE specific members from TABLE
  to ha_myisammrg.

  Moved members from TABLE to ha_myisammrg.
  Renamed some mebers.
  Fixed comments.

  Step #4: Valgrind and coverage testing

  Valgrind did not uncover new problems.
  Added purecov comments.

  Added a new test for DATA/INDEX DIRECTORY options.
  Changed handling of ::reset() for non-attached children.
  Fixed the merge-big test.

  Step #5: Fixed crashes detected during review
  Changed detection when to attach/detach.
  Added new tests.

Backport also the fix for Bug#44040 "MySQL allows creating a 
MERGE table upon VIEWs but crashes when using it"


include/my_base.h:
  WL#4144 - Lock MERGE engine children
  Added HA_EXTRA_ADD_CHILDREN_LIST and HA_EXTRA_IS_ATTACHED_CHILDREN
  for MERGE table support
mysql-test/r/merge.result:
  WL#4144 - Lock MERGE engine children
  Fixed test result.
mysql-test/t/disabled.def:
  Enable merge.test, which now is working again (WL#4144).
mysql-test/t/merge-big.test:
  Fix the messages for wait_condition (merge with WL#3726).
mysql-test/t/merge.test:
  WL#4144 - Lock MERGE engine children
  Fixed one test to meet coding standards for tests
  (upper case keywords, engine names as in SHOW ENGINES).
  Fixed error codes.
  Added a test for DATA/INDEX DIRECTORY.
mysys/thr_lock.c:
  WL#4144 - Lock MERGE engine children
  Added purecov comments.
sql/ha_partition.cc:
  WL#4144 - Lock MERGE engine children
  Added MERGE specific extra operations to ha_partition::extra().
  Extended comments.
  Changed function comment to doxygen style.
  Fixed nomenclature: 'parameter' -> 'operation'.
sql/mysql_priv.h:
  WL#4144 - Lock MERGE engine children
  Removed declarations for removed functions.
sql/sql_base.cc:
  WL#4144 - Lock MERGE engine children
  Leave the children in the query list of tables after open_tables().
  Set proper back links (prev_global).
  Attach MERGE children before and detach them after every
  statement. Even under LOCK TABLES.
  Remove children from the query list when they are detached.
  Remove lock forwarding from children to parent.
  Moved MERGE specific functions to ha_myisammrg.cc.
  Added purecov comments.
  Backport the fix for Bug#44040 "MySQL allows creating a MERGE table upon VIEWs but crashes when using it"
sql/sql_table.cc:
  WL#4144 - Lock MERGE engine children
  Changed detection of MERGE tables.
sql/table.cc:
  WL#4144 - Lock MERGE engine children
  Moved is_children_attached() method from TABLE to ha_myisammrg.
sql/table.h:
  WL#4144 - Lock MERGE engine children
  Moved all MERGE specific members from TABLE to ha_myisammrg.
storage/myisammrg/ha_myisammrg.cc:
  WL#4144 - Lock MERGE engine children
  Set proper back links in the child list (prev_global).
  Added a function for removal of the child list from the query list.
  Remove children from the query list when the parent is closed.
  Make parent lock handling a dummy (zero locks).
  Moved MERGE specific functionality from SQL layer to here.
  Moved all MERGE specific members from TABLE to ha_myisammrg.
  Renamed children list pointers.
  Added initialization and free for the children list mem_root.
  Fixed comments.
  Added purecov comments.
storage/myisammrg/ha_myisammrg.h:
  WL#4144 - Lock MERGE engine children
  Added method add_children_list().
  Moved all MERGE specific members from TABLE to ha_myisammrg.
  Renamed children list pointers.
  Added a mem_root for the children list.
storage/myisammrg/myrg_extra.c:
  WL#4144 - Lock MERGE engine children
  Changed handling of ::reset() for non-attached children.
 2009-12-03 02:09:22 +03:00
Konstantin Osipov
e3b3907c4f Backport of: 
------------------------------------------------------------
revno: 2630.4.32
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-06-19 16:39:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Ensure that metadata locking subsystem properly handles
  out-of-memory conditions. Clarified MDL interface by
  separating release of locks and removal of lock requests
  from the context.

sql/lock.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and 
  mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
sql/mdl.cc:
  Ensured that metadata locking subsystem properly handles
  out-of-memory conditions.
  Introduced new MDL_INITIALIZED state for metadata lock
  request which is used in all cases when lock is not acquired 
  and we have not associated request with object respesenting 
  lock.
  
  MDL_PENDING is now only used for requests for exclusive locks
  which are added to the MDL_LOCK::waiting_exclusive queue.
  mdl_release_lock(), mdl_acquire_exclusive_locks() and 
  mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  newly introduced mdl_remove_lock() to do this.
  Also renamed mdl_release_all_locks_for_name() to 
  emphasize that it also actually removes lock requests
  from the context.
  
  Finally mdl_try_acquire_exclusive_lock() is now returs
  information about encountered lock conflict in separate
  out parameter since its return value is used for distinguishing
  between error (e.g. due to OOM) and success.
sql/mdl.h:
  Introduced new MDL_INITIALIZED state for metadata lock
  request which is used in all cases when lock is not acquired 
  and we have not associated request with object respesenting 
  lock.
  
  MDL_PENDING is now only used for requests for exclusive locks
  which are added to the MDL_LOCK::waiting_exclusive queue.
  mdl_release_lock(), mdl_acquire_exclusive_locks() and 
  mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  newly introduced mdl_remove_lock() to do this.
  Also renamed mdl_release_all_locks_for_name() to 
  emphasize that it also actually removes lock requests
  from the context.
  
  Finally mdl_try_acquire_exclusive_lock() is now returs
  information about encountered lock conflict in separate
  out parameter since its return value is used for distinguishing
  between error (e.g. due to OOM) and success.
sql/sql_base.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
  Also adjusted open_table() to ensure that it 
  releases/removes metadata locks in case of error 
  after adding/acquiring them (unless keeping these
  lock requests is required for recovering action).
sql/sql_delete.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
sql/sql_handler.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
sql/sql_show.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
sql/sql_table.cc:
  Renamed mdl_release_all_locks_for_name() to emphasize
  that it also actually removes lock requests from the context.
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
  Finally mdl_try_acquire_exclusive_lock() is now returs
  information about encountered lock conflict in separate
  out parameter since its return value is used for distinguishing
  between error (e.g. due to OOM) and success.
 2009-12-02 19:15:40 +03:00
Alexander Nozdrin
988b25cee1 Manual merge from mysql-next-mr. 
Conflicts:
  - sql/sql_yacc.yy
 2009-12-02 18:50:14 +03:00
Konstantin Osipov
3104af49cd Backport of: 
----------------------------------------------------------
revno: 2630.10.1
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-lock-tables-tidyup
timestamp: Wed 2008-06-11 15:49:58 +0400
message:
  WL#3726, review fixes.
  Now that we have metadata locks, we don't need to keep a crippled
  TABLE instance in the table cache to indicate that a table is locked.
  Remove all code that used this technique. Instead, rely on metadata
  locks and use the standard open_table() and close_thread_table()
  to manipulate with the table cache tables.
  Removes a list of functions that have become unused (see the comment
  for sql_base.cc for details).
  Under LOCK TABLES, keep a TABLE_LIST instance for each table
  that may be temporarily closed. For that, implement an own class for
  LOCK TABLES mode, Locked_tables_list.

This is a pre-requisite patch for WL#4144.
This is not exactly a backport: there is no new 
online ALTER table in Celosia, so the old alter table
code was changed to work with the new table cache API.


mysql-test/r/lock.result:
  Update results (WL#3726 post-review patch).
mysql-test/r/trigger-compat.result:
  We take the table from the table cache now, thus no warning.
mysql-test/suite/rpl/r/rpl_trigger.result:
  We take the table from the table cache now, thus no warning.
mysql-test/t/lock.test:
  Additional tests for LOCK TABLES mode (previously not covered by
  the test suite (WL#3726).
sql/field.h:
  Remove reopen_table().
sql/lock.cc:
  Remove an obsolete parameter of mysql_lock_remove().
  It's not used anywhere now either.
sql/mysql_priv.h:
  Add 4 new open_table() flags.
  Remove declarations of removed functions.
sql/sp_head.cc:
  Rename thd->mdl_el_root to thd->locked_tables_root.
sql/sql_acl.cc:
  Use the new implementation of unlock_locked_tables().
sql/sql_base.cc:
  Implement class Locked_tables_list.
  Implement close_all_tables_for_name().
  Rewrite close_cached_tables() to use the new reopen_tables().
  Remove reopen_table(), reopen_tables(), reopen_table_entry() 
  (ex. open_unireg_entry()), close_data_files_and_leave_as_placeholders(),
  close_handle_and_leave_table_as_placeholder(), close_cached_table(),
  table_def_change_share(), reattach_merge(), reopen_name_locked_table(),
  unlink_open_table().
  
  Move acquisition of a metadata lock into an own function
  - open_table_get_mdl_lock().
sql/sql_class.cc:
  Deploy class Locked_tables_list.
sql/sql_class.h:
  Declare class Locked_tables_list.
  Keep one instance of this class in class THD.
  Rename mdl_el_root to locked_tables_root.
sql/sql_db.cc:
  Update a comment.
sql/sql_insert.cc:
  Use the plain open_table() to open a just created table in
  CREATE TABLE .. SELECT.
sql/sql_parse.cc:
  Use thd->locked_tables_list to enter and leave LTM_LOCK_TABLES mode.
sql/sql_partition.cc:
  Deploy the new method of working with partitioned table locks.
sql/sql_servers.cc:
  Update to the new signature of unlock_locked_tables().
sql/sql_table.cc:
  In mysql_rm_table_part2(), the branch that removes a table under
  LOCK TABLES, make sure that the table being dropped
  is also removed from THD::locked_tables_list.
  Update ALTER TABLE and CREATE TABLE LIKE implementation to use
  open_table() and close_all_tables_for_name() instead of 
  reopen_tables().
sql/sql_trigger.cc:
  Use the new locking way.
sql/table.h:
  Add TABLE::pos_in_locked_tables, which is used only under
  LOCK TABLES.
 2009-12-02 18:22:15 +03:00
Konstantin Osipov
e8a9191e64 Backport of: 
------------------------------------------------------------
revno: 2630.9.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Wed 2008-06-11 08:33:36 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Changed close_cached_tables() not to flush all unused TABLE
  instances when flushing individual table.
  Renamed expel_table_from_cache() to tdc_remove_table() and
  added enum parameter to be able more explicitly specify type
  of removal, rewrote its code to be more efficient.

******
Backport of:
------------------------------------------------------------
revno: 2630.9.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Wed 2008-06-11 15:53:53 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Minor changes in order to improve code readability
  and simplify debugging.


mysql-test/r/ps_ddl.result:
  Restore the original (correct) behaviour,
  now that the patch that fixes the regression
  introduced by the original patch for WL#3726 is fixed.
mysql-test/t/ps_ddl.test:
  Restore the original (correct) behaviour,
  now that the patch that fixes the regression
  introduced by the original patch for WL#3726 is fixed
sql/mysql_priv.h:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly specify 
  type of removal.
sql/sql_base.cc:
  Changed close_cached_tables() not to flush all unused TABLE
  instances when flushing individual table.
  Renamed expel_table_from_cache() to tdc_remove_table() and added
  enum parameter to be able more explicitly specify type of
  removal, rewrote its code to be more efficient. As result removed
  relink_unused() function which is no longer used.
  ******
  Improved code in close_cached_tables() according to reviewer's
  comments.
sql/sql_delete.cc:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly 
  specify type of removal.
sql/sql_rename.cc:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly 
  specify type of removal.
sql/sql_show.cc:
  Moved acquisition of high-prio shared metadata lock in which
  happens in fill_schema_table_from_frm() to separate function.
sql/sql_table.cc:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly 
  specify type of removal.
sql/sql_trigger.cc:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly 
  specify type of removal.
 2009-12-01 22:13:01 +03:00
Andrei Elkin
0eda48463c Manual resolving for the following files 
Text conflict in mysql-test/collections/default.experimental
Text conflict in mysql-test/r/show_check.result
Text conflict in mysql-test/r/sp-code.result
Text conflict in mysql-test/suite/binlog/r/binlog_tmp_table.result
Text conflict in mysql-test/suite/rpl/t/disabled.def
Text conflict in mysql-test/t/show_check.test
Text conflict in mysys/my_delete.c
Text conflict in sql/item.h
Text conflict in sql/item_cmpfunc.h
Text conflict in sql/log.cc
Text conflict in sql/mysqld.cc
Text conflict in sql/repl_failsafe.cc
Text conflict in sql/slave.cc
Text conflict in sql/sql_parse.cc
Text conflict in sql/sql_table.cc
Text conflict in sql/sql_yacc.yy
Text conflict in storage/myisam/ha_myisam.cc

Corrected results for
 stm_auto_increment_bug33029.reject      2009-12-01
		20:01:49.000000000 +0300
       <andrei> @@ -42,9 +42,6 @@
       <andrei>  RETURN i;
       <andrei>  END//
       <andrei>  CALL p1();
       <andrei> -Warnings:
       <andrei> -Note   1592    Statement may not be safe to log in statement
		format.
       <andrei> -Note   1592    Statement may not be safe to log in statement
		format.

There should be indeed no Note present because there is in fact autoincrement 
top-level query in sp() that triggers inserting in yet another auto-inc table.
(todo: alert DaoGang to improve the test).
 2009-12-01 21:07:18 +02:00
Konstantin Osipov
466ee7e540 Backport of: 
------------------------------------------------------------
revno: 2630.4.27
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Mon 2008-06-09 14:01:19 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Changed open_table() to return bool. This allows more easily to
  distinguish cases when this function succeeds but returns no TABLE
  instance (in case of view or in case of special kind of open) from
  cases when we have an error. Pointer to TABLE instance is now
  always returned in TABLE_LIST::table member.

  This change allows to get rid of false assumption in open_tables()
  implementation and makes it more clear.
 2009-12-01 17:58:31 +03:00
Konstantin Osipov
5969dcda21 Backport of: 
----------------------------------------------------------
revno: 2630.4.26
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-prelocked_mode-to-push
timestamp: Fri 2008-06-06 23:19:04 +0400
message:
  WL#3726: work on review comments.
  Remove thd->locked_tables. Always store MYSQL_LOCK instances in
  thd->lock.
  Rename thd->prelocked_mode to thd->locked_tables_mode.
  Use thd->locked_tables_mode to determine if we
  are under LOCK TABLES. Update the code to not assume that
  if thd->lock is set, LOCK TABLES mode is off.
  Review comments.


sql/ha_ndbcluster_binlog.cc:
  Don't unlock the lock under LOCK TABLES (safety).
sql/handler.cc:
  There is no thd->locked_tables any more.
  Update comments.
sql/lock.cc:
  There is no thd->locked_tables any more.
sql/log.cc:
  Rename thd->prelocked_mode to thd->locked_tables_mode.
sql/set_var.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sp_head.cc:
  Rename thd->prelocked_mode to thd->locked_tables_mode.
sql/sql_base.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
  Remove thd->locked_tables.
sql/sql_cache.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_class.cc:
  Avoid code duplication.
  Do not release the table locks prematurely if we're under LOCK TABLES.
  Use thd->locked_tables_mode instead of thd->locked_tables.
sql/sql_class.h:
  Remove thd->locked_tables.
  Make prelocked mode a kind of LOCK TABLES mode.
  Update comments.
sql/sql_cursor.cc:
  Update comments.
sql/sql_insert.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
  Rename thd->prelocked_mode to thd->locked_tables_mode.
sql/sql_load.cc:
  Rename thd->prelocked_mode to thd->locked_tables_mode.
sql/sql_parse.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
  Remove thd->locked_tables.
sql/sql_partition.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_rename.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_select.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_table.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_trigger.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_update.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_view.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
storage/myisam/ha_myisam.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
 2009-12-01 17:39:03 +03:00
Konstantin Osipov
1b078b3f2d Backport of: 
------------------------------------------------------------
revno: 2630.4.25
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Fri 2008-06-06 15:32:48 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Clarified some comments explaining control flow in
  prepare_for_repair().
 2009-12-01 17:02:32 +03:00
Konstantin Osipov
1480dafe2f Backport of: 
------------------------------------------------------------
revno: 2630.8.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w4
timestamp: Thu 2008-06-05 10:48:36 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Adjust some comments that were using old terminology
  (name locks instead of exclusive metadata locks), brought
  some of them up-to-date with current situation in code.


sql/sql_base.cc:
  Adjusted comments to use proper terminology.
sql/sql_delete.cc:
  Adjusted comments to use proper terminology.
sql/sql_handler.cc:
  Adjusted comments to use proper terminology.
sql/sql_partition.cc:
  Adjusted comments to use proper terminology also fixed
  one comment to correspond to what really happens in code.
sql/sql_show.cc:
  Adjusted comments to use proper terminology.
sql/sql_table.cc:
  Adjusted comments to use proper terminology, brought
   one of them up-to-date with current situation.
sql/sql_trigger.cc:
  Adjusted comments to use proper terminology.
sql/table.h:
  Removed two unused members of TABLE_SHARE struct.
 2009-12-01 16:51:50 +03:00
Konstantin Osipov
93b55a006d Backport of: 
------------------------------------------------------------
revno: 2630.4.20
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Wed 2008-06-04 16:27:06 +0400
message:
  WL#3726 "DDL locking for all metadata objects"

  After review fixes in progress.

  Got rid of TABLE_LIST::mdl_upgradable member and related functions
  by using special flag which to be passed to open_table() which
  asks it to take upgradable metadata lock on table being opened.


sql/mysql_priv.h:
  Added one more argument to open_n_lock_single_table() call to be
  able to pass flags to open_table() and mysql_lock_tables() called
  by it.
  Added new flag for controlling open_table() behavior asks it to
  take upgradable metadata locks on tables open for write.
sql/sql_base.cc:
  Added new flag for controlling open_table() behavior asks it to
  take upgradable metadata locks on tables open for write.
  This allowed us to get rid of TABLE_LIST::mdl_upgradable member.
  Added one more argument to open_n_lock_single_table() call to be
  able to pass flags to open_table() and mysql_lock_tables() called
  by it.
sql/sql_insert.cc:
  Added one more argument to open_n_lock_single_table() call to be
  able to pass flags to open_table() and mysql_lock_tables() called
  by it.
sql/sql_parse.cc:
  Got rid of TABLE_LIST::mdl_upgradable member by using special flag
  which to be passed to open_table() which asks it to take
  upgradable metadata lock on table being opened.  As result also
  got rid of adjust_mdl_locks_upgradability() function.
sql/sql_table.cc:
  Got rid of TABLE_LIST::mdl_upgradable member and related functions
  by using special flag which to be passed to open_table() which
  asks it to take upgradable metadata lock on table being opened.
sql/sql_view.cc:
  Got rid of TABLE_LIST::mdl_upgradable member and related functions
  by using special flag which to be passed to open_table() which
  asks it to take upgradable metadata lock on table being opened.
sql/table.h:
  Got rid of TABLE_LIST::mdl_upgradable member and related functions
  by using special flag which to be passed to open_table() which
  asks it to take upgradable metadata lock on table being opened.
 2009-12-01 16:38:00 +03:00
Konstantin Osipov
1ed585adff Backport of: 
---------------------------------------------
2630.7.3 Konstantin Osipov       2008-06-02
        Various style changes preceding the removal of reopen_table().
(Post-review fixes for WL#3726).


sql/event_db_repository.cc:
  Update to use the new signature of TABLE_LIST::init_one_table().
sql/mysql_priv.h:
  Move close_cached_table() and wait_while_table_is_used()
  to sql_base.cc.
sql/sql_base.cc:
  Move close_cached_table() and wait_while_table_is_used()
  from sql_table.cc.
sql/sql_table.cc:
  Move close_cached_table() and wait_while_table_is_used()
  to sql_base.cc.
sql/table.h:
  Update the signature of TABLE_LIST::init_one_table().
 2009-12-01 16:27:03 +03:00
Konstantin Osipov
379a441d9c Backport of: 
---------------------------------------------------------
2630.7.2 Konstantin Osipov       2008-06-02
         Fix alignment in sql_table.cc (no other changes).


sql/sql_table.cc:
  Fix alignment (no other changes).
 2009-12-01 16:14:06 +03:00
Konstantin Osipov
b05303c132 Backport of: 
------------------------------------------------------------
revno: 2630.4.18
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Tue 2008-06-03 21:07:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all requests
  for this object in the context. This makes API a bit more clear
  and makes adjust_mdl_locks_upgradability() much nicer.


sql/lock.cc:
  lock_table_names():
    Set TABLE_LIST::mdl_lock_data when allocating new metadata
    lock request object for table list element.
sql/mdl.cc:
  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context. Adjusted upgrade/
  downgrade functions accordingly.
  We also got rid of mdl_release_exclusive_locks() and
  now release locks individually. To simplify this process
  mdl_release_all_locks_for_name() was introduced.
sql/mdl.h:
  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context. Adjusted upgrade/
  downgrade functions accordingly.
  We also got rid of mdl_release_exclusive_locks() and
  now release locks individually. To simplify this process
  mdl_release_all_locks_for_name() was introduced.
sql/sql_base.cc:
  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context.
  We also got rid of mdl_release_exclusive_locks() and
  now release locks individually.
sql/sql_parse.cc:
  adjust_mdl_locks_upgradability() is much simplier now due to the
  fact that now during upgrading/downgrading metadata locks we
  deal with individual metadata lock requests rather than with
  all requests for this object in the context.
sql/sql_table.cc:
  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context. Adjusted upgrade/
  downgrade functions accordingly.
  We also got rid of mdl_release_exclusive_locks() and
  now release locks individually. To simplify this process
  mdl_release_all_locks_for_name() was introduced.
sql/sql_trigger.cc:
  ow during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context.
 2009-12-01 01:39:13 +03:00
Konstantin Osipov
e23046d1bc Backport of: 
------------------------------------------------------------
revno: 2630.4.17
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-05-29 16:52:56 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  "The great correction of names".

  Renamed MDL_LOCK and MDL_LOCK_DATA classes to make usage of
  these names in metadata locking subsystem consistent with
  other parts of server (i.e. thr_lock.cc). Now we MDL_LOCK_DATA
  corresponds to request for a lock and MDL_LOCK to the lock
  itself. Adjusted code in MDL subsystem and other places
  using these classes accordingly.
  Did similar thing for GLOBAL_MDL_LOCK_DATA class and also
  changed name of its members to correspond to names of
  MDL_LOCK_DATA members.
  Finally got rid of usage of one letter variables in MDL
  code since it makes code harder to search in (according
  to reviewer).
 2009-12-01 01:33:22 +03:00
Konstantin Osipov
cf45b61a6a Backport of: 
------------------------------------------------------------
revno: 2630.4.16
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Thu 2008-05-29 09:45:02 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review changes in progress.

  Tweaked some comments and did some renames to
  avoid ambiguites.


sql/mysql_priv.h:
  Removed name_lock_locked_table() function.
sql/sql_base.cc:
  Got rid of name_lock_locked_table() function after replacing
  the only call to it with its body.
  Simplified open_table() code by making "action" argument
  mandatory (i.e. one now should always pass non-0 pointer
  in this argument).
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
  Adjusted comments according to review.
sql/sql_handler.cc:
  Added comment clarifying in which cases we can have TABLE::mdl_lock
  set to 0.
sql/sql_insert.cc:
  Now the 4th argument of open_table() is mandatory (it makes
  no sense to complicate open_table() code when we can simply
  pass dummy variable).
sql/sql_parse.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/sql_prepare.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/sql_table.cc:
  Now the 4th argument of open_table() is mandatory (it makes
  no sense to complicate open_table() code when we can simply
  pass dummy variable).
sql/sql_trigger.cc:
  Replaced the only call to name_lock_locked_table() function
  with its body.
sql/sql_view.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/table.h:
  Renamed TABLE_LIST::open_table_type to open_type (to
  avoid confusing it with type of table) and improved
  comments describing this member.
 2009-12-01 01:13:06 +03:00