diff options
Diffstat (limited to 'sql/handler.cc')
| -rw-r--r-- | sql/handler.cc | 40 |
1 files changed, 32 insertions, 8 deletions
diff --git a/sql/handler.cc b/sql/handler.cc index eb060002f48..22bb3069a9f 100644 --- a/sql/handler.cc +++ b/sql/handler.cc @@ -29,8 +29,6 @@ #include "sql_cache.h" // query_cache, query_cache_* #include "key.h" // key_copy, key_unpack, key_cmp_if_same, key_cmp #include "sql_table.h" // build_table_filename -#include "lock.h" // wait_if_global_read_lock, - // start_waiting_global_read_lock #include "sql_parse.h" // check_stack_overrun #include "sql_acl.h" // SUPER_ACL #include "sql_base.h" // free_io_cache @@ -41,6 +39,7 @@ #include "transaction.h" #include <errno.h> #include "probes_mysql.h" +#include "debug_sync.h" // DEBUG_SYNC #ifdef WITH_PARTITION_STORAGE_ENGINE #include "ha_partition.h" @@ -1155,6 +1154,7 @@ int ha_commit_trans(THD *thd, bool all) { uint rw_ha_count; bool rw_trans; + MDL_request mdl_request; DBUG_EXECUTE_IF("crash_commit_before", DBUG_SUICIDE();); @@ -1166,11 +1166,27 @@ int ha_commit_trans(THD *thd, bool all) /* rw_trans is TRUE when we in a transaction changing data */ rw_trans= is_real_trans && (rw_ha_count > 0); - if (rw_trans && - thd->global_read_lock.wait_if_global_read_lock(thd, FALSE, FALSE)) + if (rw_trans) { - ha_rollback_trans(thd, all); - DBUG_RETURN(1); + /* + Acquire a metadata lock which will ensure that COMMIT is blocked + by an active FLUSH TABLES WITH READ LOCK (and vice versa: + COMMIT in progress blocks FTWRL). + + We allow the owner of FTWRL to COMMIT; we assume that it knows + what it does. + */ + mdl_request.init(MDL_key::COMMIT, "", "", MDL_INTENTION_EXCLUSIVE, + MDL_EXPLICIT); + + if (thd->mdl_context.acquire_lock(&mdl_request, + thd->variables.lock_wait_timeout)) + { + ha_rollback_trans(thd, all); + DBUG_RETURN(1); + } + + DEBUG_SYNC(thd, "ha_commit_trans_after_acquire_commit_lock"); } if (rw_trans && @@ -1225,8 +1241,16 @@ int ha_commit_trans(THD *thd, bool all) DBUG_EXECUTE_IF("crash_commit_after", DBUG_SUICIDE();); RUN_HOOK(transaction, after_commit, (thd, FALSE)); end: - if (rw_trans) - thd->global_read_lock.start_waiting_global_read_lock(thd); + if (rw_trans && mdl_request.ticket) + { + /* + We do not always immediately release transactional locks + after ha_commit_trans() (see uses of ha_enable_transaction()), + thus we release the commit blocker lock as soon as it's + not needed. + */ + thd->mdl_context.release_lock(mdl_request.ticket); + } } /* Free resources and perform other cleanup even for 'empty' transactions. */ else if (is_real_trans) |