Better control of the IO manager thread; improvements to deadlock checking

[ghc-hetmet.git] / rts / posix / Signals.c

diff --git a/rts/posix/Signals.c b/rts/posix/Signals.c
index 5f5f77f..2303d9f 100644 (file)
--- a/rts/posix/Signals.c
+++ b/rts/posix/Signals.c
@@ -16,6 +16,7 @@
 #include "posix/Signals.h"
 #include "RtsUtils.h"
 #include "RtsFlags.h"
+#include "Prelude.h"
 
 #ifdef alpha_HOST_ARCH
 # if defined(linux_HOST_OS)
@@ -107,6 +108,9 @@ more_handlers(I_ sig)
 // Here's the pipe into which we will send our signals
 static int io_manager_pipe = -1;
 
+#define IO_MANAGER_WAKEUP 0xff
+#define IO_MANAGER_DIE    0xfe
+
 void
 setIOManagerPipe (int fd)
 {
@@ -115,6 +119,40 @@ setIOManagerPipe (int fd)
     io_manager_pipe = fd;
 }
 
+#if defined(THREADED_RTS)
+void
+ioManagerWakeup (void)
+{
+    // Wake up the IO Manager thread by sending a byte down its pipe
+    if (io_manager_pipe >= 0) {
+       StgWord8 byte = (StgWord8)IO_MANAGER_WAKEUP;
+       write(io_manager_pipe, &byte, 1);
+    }
+}
+
+void
+ioManagerDie (void)
+{
+    // Ask the IO Manager thread to exit
+    if (io_manager_pipe >= 0) {
+       StgWord8 byte = (StgWord8)IO_MANAGER_DIE;
+       write(io_manager_pipe, &byte, 1);
+    }
+}
+
+void
+ioManagerStart (void)
+{
+    // Make sure the IO manager thread is running
+    Capability *cap;
+    if (io_manager_pipe < 0) {
+       cap = rts_lock();
+       rts_evalIO(cap,&GHCziConc_ensureIOManagerIsRunning_closure,NULL);
+       rts_unlock(cap);
+    }
+}
+#endif
+
 #if !defined(THREADED_RTS)
 
 #define N_PENDING_HANDLERS 16