bzr commit into mysql-6.0-falcon branch (klewis:2733) Bug#37587

[Kevin Lewis]

#At file:///C:/Work/bzr/Merge/mysql-6.0-falcon/

 2733 Kevin Lewis	2008-07-07
      Bug#37587 - Fix this 3 way deadlock a different way.
      Allow the gopher to hold SerialLog::pending.syncObject while
      it locks serializeGophers, but release serializeGophers before 
      getting SerialLog::pending.syncObject back.
      Then fix TableSpaceManager::dropTableSpace so that it releases
      its syncObject before calling  dropTableSpace.append().
modified:
  storage/falcon/Gopher.cpp
  storage/falcon/TableSpaceManager.cpp

per-file messages:
  storage/falcon/Gopher.cpp
    Bug#37587 - Fix this 3 way deadlock a different way.
    Allow the gopher to hold SerialLog::pending.syncObject while
    it locks serializeGophers, but release serializeGophers before 
    getting SerialLog::pending.syncObject back.
    Then fix TableSpaceManager::dropTableSpace so that it releases
    its syncObject before calling  dropTableSpace.append().
  storage/falcon/TableSpaceManager.cpp
    Bug#37587 - Fix this 3 way deadlock a different way.
    Fix TableSpaceManager::dropTableSpace so that it releases
    its syncObject before calling  dropTableSpace.append().
=== modified file 'storage/falcon/Gopher.cpp'
--- a/storage/falcon/Gopher.cpp	2008-06-30 16:51:55 +0000
+++ b/storage/falcon/Gopher.cpp	2008-07-07 06:26:23 +0000
@@ -43,8 +43,8 @@ void Gopher::gopherThread(void)
 	deadMan.lock(Shared);
 	workerThread = Thread::getThread("Gopher::gopherThread");
 	active = true;
-	Sync sync (&log->pending.syncObject, "Gopher::gopherThread pending");
-	sync.lock(Exclusive);
+	Sync syncPending (&log->pending.syncObject, "Gopher::gopherThread pending");
+	syncPending.lock(Exclusive);
 	
 	while (!workerThread->shutdownInProgress && !log->finishing)
 		{
@@ -53,18 +53,17 @@ void Gopher::gopherThread(void)
 			if (log->blocking)
 				log->unblockUpdates();
 
-			sync.unlock();
+			syncPending.unlock();
 			active = false;
 			workerThread->sleep();
 			active = true;
-			sync.lock(Exclusive);
+			syncPending.lock(Exclusive);
 
 			continue;
 			}
 		
 		SerialLogTransaction *transaction = log->pending.first;
 		log->pending.remove(transaction);
-		sync.unlock();
 
 		Sync serializeGophers(&log->syncSerializeGophers, "Gopher::gopherThread(4)");
 		if (transaction->allowConcurrentGophers)
@@ -72,10 +71,12 @@ void Gopher::gopherThread(void)
 		else
 			serializeGophers.lock(Exclusive);
 
+		syncPending.unlock();
+
 		transaction->doAction();
 
-		sync.lock(Exclusive);
 		serializeGophers.unlock();
+		syncPending.lock(Exclusive);
 
 		log->inactions.append(transaction);
 		

=== modified file 'storage/falcon/TableSpaceManager.cpp'
--- a/storage/falcon/TableSpaceManager.cpp	2008-06-17 17:41:54 +0000
+++ b/storage/falcon/TableSpaceManager.cpp	2008-07-07 06:26:23 +0000
@@ -326,8 +326,6 @@ void TableSpaceManager::dropTableSpace(T
 	statement->executeUpdate();
 	Transaction *transaction = database->getSystemTransaction();
 	transaction->hasUpdates = true;
-	pendingDrops++;
-	database->serialLog->logControl->dropTableSpace.append(tableSpace, transaction);
 
 	syncDDL.unlock();
 	database->commitSystemTransaction();
@@ -342,7 +340,11 @@ void TableSpaceManager::dropTableSpace(T
 			break;
 			}
 			
+	pendingDrops++;
 	syncObj.unlock();
+
+	database->serialLog->logControl->dropTableSpace.append(tableSpace, transaction);
+
 	tableSpace->active = false;
 }