Fix #2783: detect black-hole loops properly
[ghc.git] / rts / RaiseAsync.h
1 /* ---------------------------------------------------------------------------
2 *
3 * (c) The GHC Team, 1998-2006
4 *
5 * Asynchronous exceptions
6 *
7 * --------------------------------------------------------------------------*/
8
9 #ifndef RAISEASYNC_H
10 #define RAISEASYNC_H
11
12 #define THROWTO_SUCCESS 0
13 #define THROWTO_BLOCKED 1
14
15 #ifndef CMINUSMINUS
16 void throwToSingleThreaded (Capability *cap,
17 StgTSO *tso,
18 StgClosure *exception);
19
20 void throwToSingleThreaded_ (Capability *cap,
21 StgTSO *tso,
22 StgClosure *exception,
23 rtsBool stop_at_atomically);
24
25 void suspendComputation (Capability *cap,
26 StgTSO *tso,
27 StgUpdateFrame *stop_here);
28
29 nat throwTo (Capability *cap, // the Capability we hold
30 StgTSO *source, // the TSO sending the exception
31 StgTSO *target, // the TSO receiving the exception
32 StgClosure *exception, // the exception closure
33 /*[out]*/ void **out // pass to throwToReleaseTarget()
34 );
35
36 #ifdef THREADED_RTS
37 void throwToReleaseTarget (void *tso);
38 #endif
39
40 int maybePerformBlockedException (Capability *cap, StgTSO *tso);
41 void awakenBlockedExceptionQueue (Capability *cap, StgTSO *tso);
42
43 /* Determine whether a thread is interruptible (ie. blocked
44 * indefinitely). Interruptible threads can be sent an exception with
45 * killThread# even if they have async exceptions blocked.
46 */
47 INLINE_HEADER int
48 interruptible(StgTSO *t)
49 {
50 switch (t->why_blocked) {
51 case BlockedOnMVar:
52 case BlockedOnException:
53 case BlockedOnRead:
54 case BlockedOnWrite:
55 #if defined(mingw32_HOST_OS)
56 case BlockedOnDoProc:
57 #endif
58 case BlockedOnDelay:
59 return 1;
60 // NB. Threaded blocked on foreign calls (BlockedOnCCall) are
61 // *not* interruptible. We can't send these threads an exception.
62 default:
63 return 0;
64 }
65 }
66
67 #endif /* CMINUSMINUS */
68
69 #endif /* RAISEASYNC_H */
70