1.1 --- a/src/share/vm/runtime/thread.hpp Wed Oct 06 14:18:32 2010 -0700
1.2 +++ b/src/share/vm/runtime/thread.hpp Fri Oct 08 09:29:09 2010 -0700
1.3 @@ -1490,6 +1490,29 @@
1.4 }
1.5 #endif // !SERIALGC
1.6
1.7 + // This method initializes the SATB and dirty card queues before a
1.8 + // JavaThread is added to the Java thread list. Right now, we don't
1.9 + // have to do anything to the dirty card queue (it should have been
1.10 + // activated when the thread was created), but we have to activate
1.11 + // the SATB queue if the thread is created while a marking cycle is
1.12 + // in progress. The activation / de-activation of the SATB queues at
1.13 + // the beginning / end of a marking cycle is done during safepoints
1.14 + // so we have to make sure this method is called outside one to be
1.15 + // able to safely read the active field of the SATB queue set. Right
1.16 + // now, it is called just before the thread is added to the Java
1.17 + // thread list in the Threads::add() method. That method is holding
1.18 + // the Threads_lock which ensures we are outside a safepoint. We
1.19 + // cannot do the obvious and set the active field of the SATB queue
1.20 + // when the thread is created given that, in some cases, safepoints
1.21 + // might happen between the JavaThread constructor being called and the
1.22 + // thread being added to the Java thread list (an example of this is
1.23 + // when the structure for the DestroyJavaVM thread is created).
1.24 +#ifndef SERIALGC
1.25 + void initialize_queues();
1.26 +#else // !SERIALGC
1.27 + void initialize_queues() { }
1.28 +#endif // !SERIALGC
1.29 +
1.30 // Machine dependent stuff
1.31 #include "incls/_thread_pd.hpp.incl"
1.32
