sql/ha_innodb.cc

    protect prepare-...-commit with a mutex to ensure that commits in binlog and in the innodb have the same order
    store binlog position with the commit


innobase/include/trx0trx.h:
  comment modified
sql/ha_innodb.cc:
  protect prepare-...-commit with a mutex to ensure that commits in binlog and in the innodb have the same order
  store binlog position with the commit
sql/handler.cc:
  ha_prepare cannot return -1

innobase/include/trx0trx.h

@@ -390,8 +390,9 @@ struct trx_struct{
 	dulint		table_id;	/* table id if the preceding field is
 					TRUE */
 	/*------------------------------*/
-	int		active_trans;	/* whether a transaction in MySQL
-					is active */
+	int		active_trans;	/* 1 - if a transaction in MySQL
+					is active. 2 - if prepare_commit_mutex
+                                        was taken */
 	void*           mysql_thd;      /* MySQL thread handle corresponding
 					to this trx, or NULL */
 	char**		mysql_query_str;/* pointer to the field in mysqld_thd

sql/ha_innodb.cc

@@ -45,7 +45,8 @@ have disables the InnoDB inlining in this file. */
 
 #include "ha_innodb.h"
 
-pthread_mutex_t innobase_mutex;
+pthread_mutex_t innobase_share_mutex, // to protect innobase_open_files
+                prepare_commit_mutex; // to force correct commit order in binlog
 bool innodb_inited= 0;
 
 /* Store MySQL definition of 'byte': in Linux it is char while InnoDB
@@ -1266,7 +1267,8 @@ innobase_init(void)
 
 	(void) hash_init(&innobase_open_tables,system_charset_info, 32, 0, 0,
 			 		(hash_get_key) innobase_get_key, 0, 0);
-	pthread_mutex_init(&innobase_mutex, MY_MUTEX_INIT_FAST);
+        pthread_mutex_init(&innobase_share_mutex, MY_MUTEX_INIT_FAST);
+        pthread_mutex_init(&prepare_commit_mutex, MY_MUTEX_INIT_FAST);
 	innodb_inited= 1;
 
 	/* If this is a replication slave and we needed to do a crash recovery,
@@ -1320,7 +1322,8 @@ innobase_end(void)
 	  	hash_free(&innobase_open_tables);
 	  	my_free(internal_innobase_data_file_path,
 						MYF(MY_ALLOW_ZERO_PTR));
-	  	pthread_mutex_destroy(&innobase_mutex);
+                pthread_mutex_destroy(&innobase_share_mutex);
+                pthread_mutex_destroy(&prepare_commit_mutex);
 	}
 
   	DBUG_RETURN(err);
@@ -1478,9 +1481,20 @@ innobase_commit(
  		/* We were instructed to commit the whole transaction, or
 		this is an SQL statement end and autocommit is on */
 
+                /* We need current binlog position for HotBackup to work.
+                Note, the position is current because of prepare_commit_mutex */
+                trx->mysql_log_file_name = mysql_bin_log.get_log_fname();
+                trx->mysql_log_offset =
+                        (ib_longlong)mysql_bin_log.get_log_file()->pos_in_file;
+
 		innobase_commit_low(trx);
 
+                if (trx->active_trans == 2) {
+
+                        pthread_mutex_unlock(&prepare_commit_mutex);
+                }
                 trx->active_trans = 0;
+
 	} else {
 	        /* We just mark the SQL statement ended and do not do a
 		transaction commit */
@@ -5842,7 +5856,7 @@ static mysql_byte* innobase_get_key(INNOBASE_SHARE *share,uint *length,
 static INNOBASE_SHARE *get_share(const char *table_name)
 {
   INNOBASE_SHARE *share;
-  pthread_mutex_lock(&innobase_mutex);
+  pthread_mutex_lock(&innobase_share_mutex);
   uint length=(uint) strlen(table_name);
   if (!(share=(INNOBASE_SHARE*) hash_search(&innobase_open_tables,
 					(mysql_byte*) table_name,
@@ -5856,7 +5870,7 @@ static INNOBASE_SHARE *get_share(const char *table_name)
       strmov(share->table_name,table_name);
       if (my_hash_insert(&innobase_open_tables, (mysql_byte*) share))
       {
-	pthread_mutex_unlock(&innobase_mutex);
+        pthread_mutex_unlock(&innobase_share_mutex);
 	my_free((gptr) share,0);
 	return 0;
       }
@@ -5865,13 +5879,13 @@ static INNOBASE_SHARE *get_share(const char *table_name)
     }
   }
   share->use_count++;
-  pthread_mutex_unlock(&innobase_mutex);
+  pthread_mutex_unlock(&innobase_share_mutex);
   return share;
 }
 
 static void free_share(INNOBASE_SHARE *share)
 {
-  pthread_mutex_lock(&innobase_mutex);
+  pthread_mutex_lock(&innobase_share_mutex);
   if (!--share->use_count)
   {
     hash_delete(&innobase_open_tables, (mysql_byte*) share);
@@ -5879,7 +5893,7 @@ static void free_share(INNOBASE_SHARE *share)
     pthread_mutex_destroy(&share->mutex);
     my_free((gptr) share, MYF(0));
   }
-  pthread_mutex_unlock(&innobase_mutex);
+  pthread_mutex_unlock(&innobase_share_mutex);
 }
 
 /*********************************************************************
@@ -6318,15 +6332,19 @@ innobase_xa_prepare(
 			FALSE - the current SQL statement ended */
 {
 	int error = 0;
-        trx_t* trx;
+        trx_t* trx = check_trx_exists(thd);
+
+        if (thd->lex->sql_command != SQLCOM_XA_PREPARE) {
+
+                pthread_mutex_lock(&prepare_commit_mutex);
+                trx->active_trans = 2;
+        }
 
 	if (!thd->variables.innodb_support_xa) {
 
 		return(0);
 	}
 
-        trx = check_trx_exists(thd);
-
         trx->xid=thd->transaction.xid;
 
 	/* Release a possible FIFO ticket and search latch. Since we will

sql/handler.cc

@@ -526,7 +526,6 @@ void trans_register_ha(THD *thd, bool all, handlerton *ht_arg)
 
 /*
   RETURN
-     -1  - cannot prepare
       0  - ok
       1  - error, transaction was rolled back
 */
@@ -539,8 +538,6 @@ int ha_prepare(THD *thd)
 #ifdef USING_TRANSACTIONS
   if (trans->nht)
   {
-    if (trans->no_2pc)
-      DBUG_RETURN(-1);
     for (; *ht; ht++)
     {
       int err;