Remove MCP_GLOBAL_SCHEMA_LOCK patch

 - prepare for upmerge
 - this functionality is still only supported by Cluster
   and will not be merged up.

Author: blaudden

sql/handler.cc

@@ -5480,91 +5480,6 @@ int ha_binlog_end(THD* thd)
   return 0;
 }
 
-
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-/**
-  Fill list of htons which are initialized and have the global_schema_func set
-*/
-static my_bool global_schema_func_list(THD *thd, plugin_ref plugin, void *arg)
-{
-  hton_list_st *hton_list= (hton_list_st *)arg;
-  handlerton *hton= plugin_data<handlerton*>(plugin);
-  if (hton->state == SHOW_OPTION_YES && hton->global_schema_func)
-  {
-    uint sz= hton_list->sz;
-    if (sz == MAX_HTON_LIST_ST-1)
-    {
-      /* list full */
-      return FALSE;
-    }
-    hton_list->hton[sz]= hton;
-    hton_list->sz= sz+1;
-  }
-  return FALSE;
-}
-
-
-/**
-  Lock the global(distributed) schema lock
-*/
-static int ha_global_schema_lock(THD *thd, bool no_lock_queue)
-{
-  hton_list_st hton_list;
-  uint i, sz, res= 0;
-
-  hton_list.sz= 0;
-  plugin_foreach(thd, global_schema_func_list,
-                 MYSQL_STORAGE_ENGINE_PLUGIN, &hton_list);
-
-  for (i= 0, sz= hton_list.sz; i < sz ; i++)
-    res|= hton_list.hton[i]->global_schema_func(thd, true, (void*)no_lock_queue);
-  return res;
-}
-
-/**
-  Unlock the global(distributed) schema lock
-*/
-static int ha_global_schema_unlock(THD *thd)
-{
-  hton_list_st hton_list;
-  uint i, sz, res= 0;
-
-  hton_list.sz= 0;
-  plugin_foreach(thd, global_schema_func_list,
-                 MYSQL_STORAGE_ENGINE_PLUGIN, &hton_list);
-
-  for (i= 0, sz= hton_list.sz; i < sz ; i++)
-    res|= hton_list.hton[i]->global_schema_func(thd, false, NULL);
-  return res;
-}
-
-Ha_global_schema_lock_guard::Ha_global_schema_lock_guard(THD *thd)
-  : m_thd(thd), m_locked(false)
-{
-}
-
-Ha_global_schema_lock_guard::~Ha_global_schema_lock_guard()
-{
-  if (m_locked)
-    ha_global_schema_unlock(m_thd);
-}
-
-int Ha_global_schema_lock_guard::lock(bool no_lock_queue)
-{
-  /* only one lock call allowed */
-  DBUG_ASSERT(!m_locked);
-
-  /*
-    Always set m_locked, even if lock fails. Since the
-    lock/unlock calls are reference counted, the number
-    of calls to lock and unlock need to match up.
-  */
-  m_locked= true;
-
-  return ha_global_schema_lock(m_thd, no_lock_queue);
-}
-#endif
-
 /**
   Calculate cost of 'index only' scan for given index and number of records
 

sql/handler.h

@@ -816,9 +816,6 @@ struct handlerton
                                  const char *name);
    int (*make_pushed_join)(handlerton *hton, THD* thd, 
                            const AQP::Join_plan* plan);
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-   int (*global_schema_func)(THD* thd, bool lock, void* args);
-#endif
 
   /**
     List of all system tables specific to the SE.
@@ -3905,19 +3902,6 @@ void ha_binlog_wait(THD *thd);
 /* It is required by basic binlog features on both MySQL server and libmysqld */
 int ha_binlog_end(THD *thd);
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-class Ha_global_schema_lock_guard
-{
-public:
-  Ha_global_schema_lock_guard(THD *thd);
-  ~Ha_global_schema_lock_guard();
-  int lock(bool no_lock_queue= false);
-private:
-  THD* m_thd;
-  bool m_locked;
-};
-#endif
-
 const char *ha_legacy_type_name(legacy_db_type legacy_type);
 const char *get_canonical_filename(handler *file, const char *path,
                                    char *tmp_path);

sql/sql_db.cc

@@ -569,11 +569,6 @@ int mysql_create_db(THD *thd, const char *db, HA_CREATE_INFO *create_info,
     my_error(ER_DB_CREATE_EXISTS, MYF(0), db);
     DBUG_RETURN(-1);
   }
-  
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  Ha_global_schema_lock_guard global_schema_lock(thd);
-  (void)global_schema_lock.lock();
- #endif
 
   if (lock_schema_name(thd, db))
     DBUG_RETURN(-1);
@@ -721,11 +716,6 @@ bool mysql_alter_db(THD *thd, const char *db, HA_CREATE_INFO *create_info)
   int error= 0;
   DBUG_ENTER("mysql_alter_db");
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  Ha_global_schema_lock_guard global_schema_lock(thd);
-  (void)global_schema_lock.lock();
-#endif
-
   if (lock_schema_name(thd, db))
     DBUG_RETURN(TRUE);
 
@@ -807,10 +797,6 @@ bool mysql_rm_db(THD *thd,const LEX_CSTRING &db,bool if_exists, bool silent)
   Drop_table_error_handler err_handler;
   DBUG_ENTER("mysql_rm_db");
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  Ha_global_schema_lock_guard global_schema_lock(thd);
-  (void)global_schema_lock.lock();
- #endif
 
   if (lock_schema_name(thd, db.str))
     DBUG_RETURN(true);

sql/sql_parse.cc

@@ -2800,12 +2800,6 @@ case SQLCOM_PREPARE:
         goto end_with_restore_list;
       }
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-      Ha_global_schema_lock_guard global_schema_lock(thd);
-
-      if (!(create_info.options & HA_LEX_CREATE_TMP_TABLE))
-        (void)global_schema_lock.lock();
-#endif
       if (!(res= open_tables_for_query(thd, all_tables, 0)))
       {
         /* The table already exists */

sql/sql_rename.cc

@@ -47,9 +47,6 @@ bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent)
   char *rename_log_table[2]= {NULL, NULL};
   DBUG_ENTER("mysql_rename_tables");
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  Ha_global_schema_lock_guard global_schema_lock(thd);
-#endif
   /*
     Avoid problems with a rename on a table that we have locked or
     if the user is trying to to do this in a transcation context
@@ -138,10 +135,6 @@ bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent)
       goto err;
     }
   }
-  
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  (void)global_schema_lock.lock();
-#endif
 
   if (lock_table_names(thd, table_list, 0, thd->variables.lock_wait_timeout, 0))
     goto err;

sql/sql_table.cc

@@ -2091,10 +2091,6 @@ bool mysql_rm_table(THD *thd,TABLE_LIST *tables, my_bool if_exists,
 
   DBUG_ENTER("mysql_rm_table");
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  Ha_global_schema_lock_guard global_schema_lock(thd);
-#endif
-
   /* Disable drop of enabled log tables, must be done before name locking */
   for (table= tables; table; table= table->next_local)
   {
@@ -2118,10 +2114,6 @@ bool mysql_rm_table(THD *thd,TABLE_LIST *tables, my_bool if_exists,
 
   if (!drop_temporary)
   {
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-    (void)global_schema_lock.lock();
-#endif
-
     if (!thd->locked_tables_mode)
     {
       if (lock_table_names(thd, tables, NULL,
@@ -5247,14 +5239,6 @@ bool mysql_create_table(THD *thd, TABLE_LIST *create_table,
   uint not_used;
   DBUG_ENTER("mysql_create_table");
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  Ha_global_schema_lock_guard global_schema_lock(thd);
-  if (!(create_info->options & HA_LEX_CREATE_TMP_TABLE))
-  {
-    (void)global_schema_lock.lock();
-  }
-#endif
-
   /*
     Open or obtain "X" MDL lock on the table being created.
     To check the existence of table, lock of type "S" is obtained on the table
@@ -5505,13 +5489,6 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table, TABLE_LIST* src_table,
   uint not_used;
   DBUG_ENTER("mysql_create_like_table");
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK 
-  Ha_global_schema_lock_guard global_schema_lock(thd);
- 
-  if (!(create_info->options & HA_LEX_CREATE_TMP_TABLE))
-    (void)global_schema_lock.lock();
-#endif
-
   /*
     We the open source table to get its description in HA_CREATE_INFO
     and Alter_info objects. This also acquires a shared metadata lock
@@ -8458,32 +8435,6 @@ bool mysql_alter_table(THD *thd, const char *new_db, const char *new_name,
     DBUG_RETURN(true);
   }
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  Ha_global_schema_lock_guard global_schema_lock_guard(thd);
-  if (ha_legacy_type(table->s->db_type()) == DB_TYPE_NDBCLUSTER ||
-      ha_legacy_type(create_info->db_type) == DB_TYPE_NDBCLUSTER)
-  {
-    // From or to engine is NDB 
-    if (thd->locked_tables_mode)
-    {
-      /*
-        To avoid deadlock in this situation:
-        - if other thread has lock do not enter lock queue
-        and report an error instead
-      */
-      if (global_schema_lock_guard.lock(true))
-      {
-        my_error(ER_LOCK_OR_ACTIVE_TRANSACTION, MYF(0));
-        DBUG_RETURN(TRUE);
-      }
-    }
-    else
-    {
-      global_schema_lock_guard.lock();
-    }
-  }
-#endif
-
   Alter_table_ctx alter_ctx(thd, table_list, tables_opened, new_db, new_name);
 
   /*

sql/sql_truncate.cc

@@ -424,9 +424,6 @@ bool Sql_cmd_truncate_table::truncate_table(THD *thd, TABLE_LIST *table_ref)
   bool binlog_stmt;
   DBUG_ENTER("Sql_cmd_truncate_table::truncate_table");
 
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-  Ha_global_schema_lock_guard global_schema_lock_guard(thd);
-#endif
   DBUG_ASSERT((!table_ref->table) ||
               (table_ref->table && table_ref->table->s));
 
@@ -470,10 +467,6 @@ bool Sql_cmd_truncate_table::truncate_table(THD *thd, TABLE_LIST *table_ref)
   }
   else /* It's not a temporary table. */
   {
-#ifndef MCP_GLOBAL_SCHEMA_LOCK
-    global_schema_lock_guard.lock();
-#endif
-
     bool hton_can_recreate;
 
     if (lock_table(thd, table_ref, &hton_can_recreate))