Merge bodhi.(none):/opt/local/work/mysql-5.0-runtime

into  bodhi.(none):/opt/local/work/mysql-5.1-runtime

sql/sql_insert.cc

@@ -1761,18 +1761,18 @@ Delayed_insert *find_handler(THD *thd, TABLE_LIST *table_list)
   thd->proc_info="waiting for delay_list";
   pthread_mutex_lock(&LOCK_delayed_insert);	// Protect master list
   I_List_iterator<Delayed_insert> it(delayed_threads);
-  Delayed_insert *tmp;
-  while ((tmp=it++))
+  Delayed_insert *di;
+  while ((di= it++))
   {
-    if (!strcmp(tmp->thd.db, table_list->db) &&
-	!strcmp(table_list->table_name, tmp->table->s->table_name.str))
+    if (!strcmp(table_list->db, di->table_list.db) &&
+	!strcmp(table_list->table_name, di->table_list.table_name))
     {
-      tmp->lock();
+      di->lock();
       break;
     }
   }
   pthread_mutex_unlock(&LOCK_delayed_insert); // For unlink from list
-  return tmp;
+  return di;
 }
 
 
@@ -1798,21 +1798,41 @@ Delayed_insert *find_handler(THD *thd, TABLE_LIST *table_list)
                 Two latter cases indicate a request for lock upgrade.
 
   XXX: why do we regard INSERT DELAYED into a view as an error and
-  do not simply a lock upgrade?
+  do not simply perform a lock upgrade?
+
+  TODO: The approach with using two mutexes to work with the
+  delayed thread list -- LOCK_delayed_insert and
+  LOCK_delayed_create -- is redundant, and we only need one of
+  them to protect the list.  The reason we have two locks is that
+  we do not want to block look-ups in the list while we're waiting
+  for the newly created thread to open the delayed table. However,
+  this wait itself is redundant -- we always call get_local_table
+  later on, and there wait again until the created thread acquires
+  a table lock.
+
+  As is redundant the concept of locks_in_memory, since we already
+  have another counter with similar semantics - tables_in_use,
+  both of them are devoted to counting the number of producers for
+  a given consumer (delayed insert thread), only at different
+  stages of producer-consumer relationship.
+
+  'dead' and 'status' variables in Delayed_insert are redundant
+  too, since there is already 'di->thd.killed' and
+  di->stacked_inserts.
 */
 
 static
 bool delayed_get_table(THD *thd, TABLE_LIST *table_list)
 {
   int error;
-  Delayed_insert *tmp;
+  Delayed_insert *di;
   DBUG_ENTER("delayed_get_table");
 
   /* Must be set in the parser */
   DBUG_ASSERT(table_list->db);
 
   /* Find the thread which handles this table. */
-  if (!(tmp=find_handler(thd,table_list)))
+  if (!(di= find_handler(thd, table_list)))
   {
     /*
       No match. Create a new thread to handle the table, but
@@ -1826,9 +1846,9 @@ bool delayed_get_table(THD *thd, TABLE_LIST *table_list)
       The first search above was done without LOCK_delayed_create.
       Another thread might have created the handler in between. Search again.
     */
-    if (! (tmp= find_handler(thd, table_list)))
+    if (! (di= find_handler(thd, table_list)))
     {
-      if (!(tmp=new Delayed_insert()))
+      if (!(di= new Delayed_insert()))
       {
 	my_error(ER_OUTOFMEMORY,MYF(0),sizeof(Delayed_insert));
         thd->fatal_error();
@@ -1837,28 +1857,30 @@ bool delayed_get_table(THD *thd, TABLE_LIST *table_list)
       pthread_mutex_lock(&LOCK_thread_count);
       thread_count++;
       pthread_mutex_unlock(&LOCK_thread_count);
-      tmp->thd.set_db(table_list->db, strlen(table_list->db));
-      tmp->thd.query= my_strdup(table_list->table_name,MYF(MY_WME));
-      if (tmp->thd.db == NULL || tmp->thd.query == NULL)
+      di->thd.set_db(table_list->db, strlen(table_list->db));
+      di->thd.query= my_strdup(table_list->table_name, MYF(MY_WME));
+      if (di->thd.db == NULL || di->thd.query == NULL)
       {
         /* The error is reported */
-	delete tmp;
+	delete di;
         thd->fatal_error();
         goto end_create;
       }
-      tmp->table_list= *table_list;			// Needed to open table
-      tmp->table_list.alias= tmp->table_list.table_name= tmp->thd.query;
-      tmp->lock();
-      pthread_mutex_lock(&tmp->mutex);
-      if ((error=pthread_create(&tmp->thd.real_id,&connection_attrib,
-				handle_delayed_insert,(void*) tmp)))
+      di->table_list= *table_list;			// Needed to open table
+      /* Replace volatile strings with local copies */
+      di->table_list.alias= di->table_list.table_name= di->thd.query;
+      di->table_list.db= di->thd.db;
+      di->lock();
+      pthread_mutex_lock(&di->mutex);
+      if ((error= pthread_create(&di->thd.real_id, &connection_attrib,
+                                 handle_delayed_insert, (void*) di)))
       {
 	DBUG_PRINT("error",
 		   ("Can't create thread to handle delayed insert (error %d)",
 		    error));
-	pthread_mutex_unlock(&tmp->mutex);
-	tmp->unlock();
-	delete tmp;
+	pthread_mutex_unlock(&di->mutex);
+	di->unlock();
+	delete di;
 	my_error(ER_CANT_CREATE_THREAD, MYF(0), error);
         thd->fatal_error();
         goto end_create;
@@ -1866,15 +1888,15 @@ bool delayed_get_table(THD *thd, TABLE_LIST *table_list)
 
       /* Wait until table is open */
       thd->proc_info="waiting for handler open";
-      while (!tmp->thd.killed && !tmp->table && !thd->killed)
+      while (!di->thd.killed && !di->table && !thd->killed)
       {
-	pthread_cond_wait(&tmp->cond_client,&tmp->mutex);
+	pthread_cond_wait(&di->cond_client, &di->mutex);
       }
-      pthread_mutex_unlock(&tmp->mutex);
+      pthread_mutex_unlock(&di->mutex);
       thd->proc_info="got old table";
-      if (tmp->thd.killed)
+      if (di->thd.killed)
       {
-        if (tmp->thd.net.report_error)
+        if (di->thd.net.report_error)
         {
           /*
             Copy the error message. Note that we don't treat fatal
@@ -1882,31 +1904,34 @@ bool delayed_get_table(THD *thd, TABLE_LIST *table_list)
             main thread. Use of my_message will enable stored
             procedures continue handlers.
           */
-          my_message(tmp->thd.net.last_errno, tmp->thd.net.last_error,
+          my_message(di->thd.net.last_errno, di->thd.net.last_error,
                      MYF(0));
 	}
-	tmp->unlock();
+	di->unlock();
         goto end_create;
       }
       if (thd->killed)
       {
-	tmp->unlock();
+	di->unlock();
 	goto end_create;
       }
+      pthread_mutex_lock(&LOCK_delayed_insert);
+      delayed_threads.append(di);
+      pthread_mutex_unlock(&LOCK_delayed_insert);
     }
     pthread_mutex_unlock(&LOCK_delayed_create);
   }
 
-  pthread_mutex_lock(&tmp->mutex);
-  table_list->table= tmp->get_local_table(thd);
-  pthread_mutex_unlock(&tmp->mutex);
+  pthread_mutex_lock(&di->mutex);
+  table_list->table= di->get_local_table(thd);
+  pthread_mutex_unlock(&di->mutex);
   if (table_list->table)
   {
     DBUG_ASSERT(thd->net.report_error == 0);
-    thd->di=tmp;
+    thd->di= di;
   }
   /* Unlock the delayed insert object after its last access. */
-  tmp->unlock();
+  di->unlock();
   DBUG_RETURN((table_list->table == NULL));
 
 end_create:
@@ -2155,26 +2180,26 @@ void kill_delayed_threads(void)
   VOID(pthread_mutex_lock(&LOCK_delayed_insert)); // For unlink from list
 
   I_List_iterator<Delayed_insert> it(delayed_threads);
-  Delayed_insert *tmp;
-  while ((tmp=it++))
+  Delayed_insert *di;
+  while ((di= it++))
   {
-    tmp->thd.killed= THD::KILL_CONNECTION;
-    if (tmp->thd.mysys_var)
+    di->thd.killed= THD::KILL_CONNECTION;
+    if (di->thd.mysys_var)
     {
-      pthread_mutex_lock(&tmp->thd.mysys_var->mutex);
-      if (tmp->thd.mysys_var->current_cond)
+      pthread_mutex_lock(&di->thd.mysys_var->mutex);
+      if (di->thd.mysys_var->current_cond)
       {
 	/*
 	  We need the following test because the main mutex may be locked
 	  in handle_delayed_insert()
 	*/
-	if (&tmp->mutex != tmp->thd.mysys_var->current_mutex)
-	  pthread_mutex_lock(tmp->thd.mysys_var->current_mutex);
-	pthread_cond_broadcast(tmp->thd.mysys_var->current_cond);
-	if (&tmp->mutex != tmp->thd.mysys_var->current_mutex)
-	  pthread_mutex_unlock(tmp->thd.mysys_var->current_mutex);
+	if (&di->mutex != di->thd.mysys_var->current_mutex)
+	  pthread_mutex_lock(di->thd.mysys_var->current_mutex);
+	pthread_cond_broadcast(di->thd.mysys_var->current_cond);
+	if (&di->mutex != di->thd.mysys_var->current_mutex)
+	  pthread_mutex_unlock(di->thd.mysys_var->current_mutex);
       }
-      pthread_mutex_unlock(&tmp->thd.mysys_var->mutex);
+      pthread_mutex_unlock(&di->thd.mysys_var->mutex);
     }
   }
   VOID(pthread_mutex_unlock(&LOCK_delayed_insert)); // For unlink from list
@@ -2248,11 +2273,6 @@ pthread_handler_t handle_delayed_insert(void *arg)
   }
   di->table->copy_blobs=1;
 
-  /* One can now use this */
-  pthread_mutex_lock(&LOCK_delayed_insert);
-  delayed_threads.append(di);
-  pthread_mutex_unlock(&LOCK_delayed_insert);
-
   /* Tell client that the thread is initialized */
   pthread_cond_signal(&di->cond_client);