INFO_TABLE_RET( stg_unblockAsyncExceptionszh_ret,
0/*framesize*/, 0/*bitmap*/, RET_SMALL )
{
+ CInt r;
+
// Not true: see comments above
// ASSERT(StgTSO_blocked_exceptions(CurrentTSO) != NULL);
- foreign "C" awakenBlockedExceptionQueue(MyCapability() "ptr",
- CurrentTSO "ptr") [R1];
-
StgTSO_flags(CurrentTSO) = StgTSO_flags(CurrentTSO) &
~(TSO_BLOCKEX::I32|TSO_INTERRUPTIBLE::I32);
+ /* Eagerly raise a blocked exception, if there is one */
+ if (StgTSO_blocked_exceptions(CurrentTSO) != END_TSO_QUEUE) {
+ /*
+ * We have to be very careful here, as in killThread#, since
+ * we are about to raise an async exception in the current
+ * thread, which might result in the thread being killed.
+ */
+ SAVE_THREAD_STATE();
+ r = foreign "C" maybePerformBlockedException (MyCapability() "ptr",
+ CurrentTSO "ptr") [R1];
+
+ if (r != 0::CInt) {
+ if (StgTSO_what_next(CurrentTSO) == ThreadKilled::I16) {
+ R1 = ThreadFinished;
+ jump StgReturn;
+ } else {
+ LOAD_THREAD_STATE();
+ ASSERT(StgTSO_what_next(CurrentTSO) == ThreadRunGHC::I16);
+ jump %ENTRY_CODE(Sp(0));
+ }
+ }
+ }
+
#ifdef REG_R1
Sp_adj(1);
jump %ENTRY_CODE(Sp(0));
unblockAsyncExceptionszh_fast
{
+ CInt r;
+
/* Args: R1 :: IO a */
STK_CHK_GEN( WDS(2), R1_PTR, unblockAsyncExceptionszh_fast);
if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX) != 0) {
- foreign "C" awakenBlockedExceptionQueue(MyCapability() "ptr",
- CurrentTSO "ptr") [R1];
StgTSO_flags(CurrentTSO) = StgTSO_flags(CurrentTSO) &
~(TSO_BLOCKEX::I32|TSO_INTERRUPTIBLE::I32);
+ /* Eagerly raise a blocked exception, if there is one */
+ if (StgTSO_blocked_exceptions(CurrentTSO) != END_TSO_QUEUE) {
+ /*
+ * We have to be very careful here, as in killThread#, since
+ * we are about to raise an async exception in the current
+ * thread, which might result in the thread being killed.
+ */
+ SAVE_THREAD_STATE();
+ r = foreign "C" maybePerformBlockedException (MyCapability() "ptr",
+ CurrentTSO "ptr") [R1];
+
+ if (r != 0::CInt) {
+ if (StgTSO_what_next(CurrentTSO) == ThreadKilled::I16) {
+ R1 = ThreadFinished;
+ jump StgReturn;
+ } else {
+ LOAD_THREAD_STATE();
+ ASSERT(StgTSO_what_next(CurrentTSO) == ThreadRunGHC::I16);
+ jump %ENTRY_CODE(Sp(0));
+ }
+ }
+ }
+
/* avoid growing the stack unnecessarily */
if (Sp(0) == stg_unblockAsyncExceptionszh_ret_info) {
Sp_adj(1);
queue, but not perform any throwTo() immediately. This might be
more appropriate when the target thread is the one actually running
(see Exception.cmm).
+
+ Returns: non-zero if an exception was raised, zero otherwise.
-------------------------------------------------------------------------- */
-void
+int
maybePerformBlockedException (Capability *cap, StgTSO *tso)
{
StgTSO *source;
// locked it.
if (tso->blocked_exceptions == END_TSO_QUEUE) {
unlockTSO(tso);
- return;
+ return 0;
}
// We unblock just the first thread on the queue, and perform
tso->blocked_exceptions = unblockOne_(cap, source,
rtsFalse/*no migrate*/);
unlockTSO(tso);
+ return 1;
}
+ return 0;
}
void