/* -----------------------------------------------------------------------------
- * $Id: Itimer.c,v 1.7 1999/12/01 14:19:36 simonmar Exp $
+ * $Id: Itimer.c,v 1.17 2000/08/25 13:12:07 simonmar Exp $
*
* (c) The GHC Team, 1995-1999
*
#endif
#include "Rts.h"
+#include "RtsFlags.h"
#include "Itimer.h"
+#include "Proftimer.h"
#include "Schedule.h"
/* As recommended in the autoconf manual */
#endif
lnat total_ticks = 0;
-rtsBool do_prof_ticks = rtsFalse;
-static void handle_tick(int unused STG_UNUSED);
+/* ticks left before next pre-emptive context switch */
+int ticks_to_ctxt_switch = 0;
+
+static
+void
+#if defined(mingw32_TARGET_OS) || (defined(cygwin32_TARGET_OS) && !defined(HAVE_SETITIMER))
+CALLBACK
+#endif
+handle_tick(int unused STG_UNUSED);
/* -----------------------------------------------------------------------------
Tick handler
signal handler.
-------------------------------------------------------------------------- */
-static void
+static
+void
+#if defined(mingw32_TARGET_OS) || (defined(cygwin32_TARGET_OS) && !defined(HAVE_SETITIMER))
+CALLBACK
+#endif
handle_tick(int unused STG_UNUSED)
{
total_ticks++;
#ifdef PROFILING
- if (do_prof_ticks = rtsTrue) {
- CCS_TICK(CCCS);
- }
+ handleProfTick();
#endif
- /* For threadDelay etc., see Select.c */
- ticks_since_select++;
+ /* so we can get a rough indication of the current time at any point
+ * without having to call gettimeofday() (see Select.c):
+ */
+ ticks_since_timestamp++;
+
+ ticks_to_ctxt_switch--;
+ if (ticks_to_ctxt_switch <= 0) {
+ ticks_to_ctxt_switch = RtsFlags.ConcFlags.ctxtSwitchTicks;
+ context_switch = 1; /* schedule a context switch */
+ }
}
0,
TIME_PERIODIC);
# endif
+
return 0;
}
initialize_virtual_timer(nat ms)
{
# ifndef HAVE_SETITIMER
- fprintf(stderr, "No virtual timer on this system\n");
+ /* fprintf(stderr, "No virtual timer on this system\n"); */
return -1;
# else
struct itimerval it;
+ timestamp = getourtimeofday();
+ ticks_since_timestamp = 0;
+
it.it_value.tv_sec = ms / 1000;
it.it_value.tv_usec = 1000 * (ms - (1000 * it.it_value.tv_sec));
it.it_interval = it.it_value;
struct itimerspec it;
timer_t tid;
+ timestamp = getourtimeofday();
+ ticks_since_timestamp = 0;
+
se.sigev_notify = SIGEV_SIGNAL;
se.sigev_signo = SIGVTALRM;
se.sigev_value.sival_int = SIGVTALRM;
if (timer_create(CLOCK_VIRTUAL, &se, &tid)) {
- fprintf(stderr, "Can't create virtual timer.\n");
- EXIT(EXIT_FAILURE);
+ barf("can't create virtual timer");
}
it.it_value.tv_sec = ms / 1000;
it.it_value.tv_nsec = 1000000 * (ms - 1000 * it.it_value.tv_sec);
(void) sigprocmask(SIG_UNBLOCK, &signals, NULL);
}
#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.
+ */
+unsigned int
+getourtimeofday(void)
+{
+ struct timeval tv;
+ gettimeofday(&tv, (struct timezone *) NULL);
+ return (tv.tv_sec * TICK_FREQUENCY +
+ tv.tv_usec * TICK_FREQUENCY / 1000000);
+}