RTS tidyup sweep, first phase

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

diff --git a/rts/posix/Itimer.c b/rts/posix/Itimer.c
index df95f21..3a09e80 100644 (file)
--- a/rts/posix/Itimer.c
+++ b/rts/posix/Itimer.c
@@ -1,6 +1,6 @@
 /* -----------------------------------------------------------------------------
  *
- * (c) The GHC Team, 1995-1999
+ * (c) The GHC Team, 1995-2007
  *
  * Interval timer for profiling and pre-emptive scheduling.
  *
@@ -16,15 +16,15 @@
  * Hence, we use the old-fashioned @setitimer@ that just about everyone seems
  * to support.  So much for standards.
  */
+
+#include "PosixSource.h"
 #include "Rts.h"
-#include "RtsFlags.h"
-#include "Timer.h"
+
 #include "Ticker.h"
-#include "posix/Itimer.h"
+#include "Itimer.h"
 #include "Proftimer.h"
-#include "Storage.h"
 #include "Schedule.h"
-#include "posix/Select.h"
+#include "Select.h"
 
 /* As recommended in the autoconf manual */
 # ifdef TIME_WITH_SYS_TIME
@@ -42,6 +42,8 @@
 # include <signal.h>
 #endif
 
+#include <string.h>
+
 /* Major bogosity:
  * 
  * In the threaded RTS, we can't set the virtual timer because the
@@ -78,9 +80,10 @@
 
 #elif defined(HAVE_SETITIMER)
 
-#  ifdef THREADED_RTS
+#  if defined(THREADED_RTS) || !defined(HAVE_SETITIMER_VIRTUAL)
 //   Oh dear, we have to use SIGALRM if there's no timer_create and
 //   we're using the THREADED_RTS.  This leads to problems, see bug #850.
+//   We also use it if we don't have a virtual timer (trac #2883).
 #    define ITIMER_SIGNAL  SIGALRM
 #    define ITIMER_FLAVOUR ITIMER_REAL
 #  else
@@ -95,9 +98,11 @@
 #endif
 
 #if defined(USE_TIMER_CREATE)
-timer_t timer;
+static timer_t timer;
 #endif
 
+static nat itimer_interval = 50;
+
 static
 void
 install_vtalrm_handler(TickProc handle_tick)
@@ -127,7 +132,7 @@ install_vtalrm_handler(TickProc handle_tick)
 }
 
 void
-startTicker(nat ms, TickProc handle_tick)
+initTicker (nat ms, TickProc handle_tick)
 {
     install_vtalrm_handler(handle_tick);
 
@@ -135,23 +140,37 @@ startTicker(nat ms, TickProc handle_tick)
     timestamp = getourtimeofday();
 #endif
 
+    itimer_interval = ms;
+
 #if defined(USE_TIMER_CREATE)
     {
-        struct itimerspec it;
         struct sigevent ev;
 
+       // Keep programs like valgrind happy
+       memset(&ev, 0, sizeof(ev));
+
         ev.sigev_notify = SIGEV_SIGNAL;
         ev.sigev_signo  = ITIMER_SIGNAL;
-        
-        it.it_value.tv_sec = ms / 1000;
-        it.it_value.tv_nsec = (ms % 1000) * 1000000;
-        it.it_interval = it.it_value;
-        
+
         if (timer_create(TIMER_FLAVOUR, &ev, &timer) != 0) {
             sysErrorBelch("timer_create");
             stg_exit(EXIT_FAILURE);
         }
+    }
+#endif
+}
 
+void
+startTicker(void)
+{
+#if defined(USE_TIMER_CREATE)
+    {
+        struct itimerspec it;
+        
+        it.it_value.tv_sec = itimer_interval / 1000;
+        it.it_value.tv_nsec = (itimer_interval % 1000) * 1000000;
+        it.it_interval = it.it_value;
+        
         if (timer_settime(timer, 0, &it, NULL) != 0) {
             sysErrorBelch("timer_settime");
             stg_exit(EXIT_FAILURE);
@@ -161,8 +180,8 @@ startTicker(nat ms, TickProc handle_tick)
     {
         struct itimerval it;
 
-        it.it_value.tv_sec = ms / 1000;
-        it.it_value.tv_usec = (ms % 1000) * 1000;
+        it.it_value.tv_sec = itimer_interval / 1000;
+        it.it_value.tv_usec = (itimer_interval % 1000) * 1000;
         it.it_interval = it.it_value;
         
         if (setitimer(ITIMER_FLAVOUR, &it, NULL) != 0) {
@@ -201,30 +220,14 @@ stopTicker(void)
 #endif
 }
 
-#if 0
-/* Currently unused */
-void
-block_vtalrm_signal(void)
-{
-    sigset_t signals;
-    
-    sigemptyset(&signals);
-    sigaddset(&signals, ITIMER_SIGNAL);
-
-    (void) sigprocmask(SIG_BLOCK, &signals, NULL);
-}
-
 void
-unblock_vtalrm_signal(void)
+exitTicker(void)
 {
-    sigset_t signals;
-    
-    sigemptyset(&signals);
-    sigaddset(&signals, ITIMER_SIGNAL);
-
-    (void) sigprocmask(SIG_UNBLOCK, &signals, NULL);
-}
+#if defined(USE_TIMER_CREATE)
+    timer_delete(timer);
+    // ignore errors - we don't really care if it fails.
 #endif
+}
 
 /* gettimeofday() takes around 1us on our 500MHz PIII.  Since we're
  * only calling it 50 times/s, it shouldn't have any great impact.
@@ -237,7 +240,8 @@ getourtimeofday(void)
   interval = RtsFlags.MiscFlags.tickInterval;
   if (interval == 0) { interval = 50; }
   gettimeofday(&tv, (struct timezone *) NULL);
-       // cast to lnat because nat may be 64 bit when int is only 32 bit
-  return ((lnat)tv.tv_sec * 1000 / interval +
-         (lnat)tv.tv_usec / (interval * 1000));
+
+  // Avoid overflow when we multiply seconds by 1000.  See #2848
+  return (lnat)((StgWord64)tv.tv_sec * 1000 / interval +
+                (StgWord64)tv.tv_usec / (interval * 1000));
 }