Apply InnoDB snapshot innodb-5.1-ss2637, part 3. Fixes

Bug #39483: InnoDB hang on adaptive hash because of out of order ::open() call by MySQL


Detailed revision comments:

r2630 | inaam | 2008-09-16 19:11:26 +0300 (Tue, 16 Sep 2008) | 11 lines
branches/5.1   bug#39483 InnoDB hang on adaptive hash because of out
of order ::open() call by MySQL

Forward port of r2629

Under some conditions MySQL calls ::open with search_latch leading
to a deadlock as we try to acquire dict_sys->mutex inside ::open
breaking the latching order. The fix is to release search_latch.

Reviewed by: Heikki

storage/innobase/handler/ha_innodb.cc

@@ -2298,6 +2298,14 @@ ha_innobase::open(
 	UT_NOT_USED(test_if_locked);
 
 	thd = ha_thd();
+
+	/* Under some cases MySQL seems to call this function while
+	holding btr_search_latch. This breaks the latching order as
+	we acquire dict_sys->mutex below and leads to a deadlock. */
+	if (thd != NULL) {
+		innobase_release_temporary_latches(ht, thd);
+	}
+
 	normalize_table_name(norm_name, name);
 
 	user_thd = NULL;