bzr commit into mysql-5.1-bugteam branch (kostja:2912) Bug#43685

[Konstantin Osipov]

#At file:///opt/local/work/mysql-5.1-bugteam/ based on revid:bjorn.munch@stripped

 2912 Konstantin Osipov	2009-05-27
      A tentative fix for Bug#43685 "Lock table affects other non-related
      tables"
      
      FLUSH TABLE <table_list> in 5.1 would wait for all tables with 
      old versions to go away from the table definition cache, 
      rather than only waiting for tables in the <table_list>.
      
      The fix is to back-port a more elaborate FLUSH TABLES
      implementation from 6.0.
      modified:
        sql/sql_base.cc

=== modified file 'sql/sql_base.cc'
--- a/sql/sql_base.cc	2009-05-15 13:03:22 +0000
+++ b/sql/sql_base.cc	2009-05-27 11:43:52 +0000
@@ -957,34 +957,51 @@ bool close_cached_tables(THD *thd, TABLE
     while (found && ! thd->killed)
     {
       found=0;
-      for (uint idx=0 ; idx < open_cache.records ; idx++)
+      if (! tables)
       {
-	TABLE *table=(TABLE*) hash_element(&open_cache,idx);
-        /* Avoid a self-deadlock. */
-        if (table->in_use == thd)
-          continue;
-        /*
-          Note that we wait here only for tables which are actually open, and
-          not for placeholders with TABLE::open_placeholder set. Waiting for
-          latter will cause deadlock in the following scenario, for example:
-
-          conn1: lock table t1 write;
-          conn2: lock table t2 write;
-          conn1: flush tables;
-          conn2: flush tables;
-
-          It also does not make sense to wait for those of placeholders that
-          are employed by CREATE TABLE as in this case table simply does not
-          exist yet.
-        */
-	if (table->needs_reopen_or_name_lock() && (table->db_stat ||
-            (table->open_placeholder && wait_for_placeholders)))
-	{
-	  found=1;
-          DBUG_PRINT("signal", ("Waiting for COND_refresh"));
-	  pthread_cond_wait(&COND_refresh,&LOCK_open);
-	  break;
-	}
+        for (uint idx=0 ; idx < open_cache.records ; idx++)
+        {
+          TABLE *table=(TABLE*) hash_element(&open_cache,idx);
+          /* Avoid a self-deadlock. */
+          if (table->in_use == thd)
+            continue;
+          /*
+            Note that we wait here only for tables which are actually open, and
+            not for placeholders with TABLE::open_placeholder set. Waiting for
+            latter will cause deadlock in the following scenario, for example:
+
+            conn1: lock table t1 write;
+            conn2: lock table t2 write;
+            conn1: flush tables;
+            conn2: flush tables;
+
+            It also does not make sense to wait for those of placeholders that
+            are employed by CREATE TABLE as in this case table simply does not
+            exist yet.
+          */
+          if (table->needs_reopen_or_name_lock() && (table->db_stat ||
+              (table->open_placeholder && wait_for_placeholders)))
+          {
+            found=1;
+            DBUG_PRINT("signal", ("Waiting for COND_refresh"));
+            pthread_cond_wait(&COND_refresh,&LOCK_open);
+            break;
+          }
+        }
+      }
+      else
+      {
+        for (TABLE_LIST *table= tables; table; table= table->next_local)
+        {
+          TABLE_SHARE *share= get_cached_table_share(table->db,
+                                                     table->table_name);
+          if (share && share->version != refresh_version)
+          {
+            found= 1;
+            pthread_cond_wait(&COND_refresh,&LOCK_open);
+            break;
+          }
+        }
       }
     }
     /*