/* -----------------------------------------------------------------------------
- * $Id: Itimer.c,v 1.4 1999/03/03 19:00:07 sof Exp $
+ * $Id: Itimer.c,v 1.23 2001/08/14 13:40:09 sewardj Exp $
*
* (c) The GHC Team, 1995-1999
*
* to support. So much for standards.
*/
-#if !defined(_AIX)
-# define NON_POSIX_SOURCE
-#endif
+/* This is not posix compliant. */
+/* #include "PosixSource.h" */
#include "Rts.h"
+#include "RtsFlags.h"
#include "Itimer.h"
+#include "Proftimer.h"
+#include "Schedule.h"
/* As recommended in the autoconf manual */
# ifdef TIME_WITH_SYS_TIME
# include <windows.h>
#endif
+lnat total_ticks = 0;
+
+/* ticks left before next pre-emptive context switch */
+int ticks_to_ctxt_switch = 0;
+
+/* -----------------------------------------------------------------------------
+ Tick handler
+
+ We use the ticker for time profiling.
+
+ SMP note: this signal could be delivered to *any* thread. We have
+ to ensure that it doesn't matter which thread actually runs the
+ signal handler.
+ -------------------------------------------------------------------------- */
+
+static
+void
+#if defined(mingw32_TARGET_OS) || (defined(cygwin32_TARGET_OS) && !defined(HAVE_SETITIMER))
+CALLBACK
+handle_tick(UINT uID STG_UNUSED, UINT uMsg STG_UNUSED, DWORD dwUser STG_UNUSED,
+ DWORD dw1 STG_UNUSED, DWORD d STG_UNUSED)
+#else
+handle_tick(int unused STG_UNUSED)
+#endif
+{
+ total_ticks++;
+
+#ifdef PROFILING
+ handleProfTick();
+#endif
+
+ /* 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++;
+
+ if (RtsFlags.ConcFlags.ctxtSwitchTicks > 0) {
+ ticks_to_ctxt_switch--;
+ if (ticks_to_ctxt_switch <= 0) {
+ ticks_to_ctxt_switch = RtsFlags.ConcFlags.ctxtSwitchTicks;
+ context_switch = 1; /* schedule a context switch */
+ }
+ }
+}
+
+
/*
* Handling timer events under cygwin32 is not done with signal/setitimer.
* Instead of the two steps of first registering a signal handler to handle
#if defined(mingw32_TARGET_OS) || (defined(cygwin32_TARGET_OS) && !defined(HAVE_SETITIMER))
-/*
- vtalrm_handler is assigned and set up in Signals.c
-
- vtalrm_id (defined in Signals.c) holds
- the system id for the current timer (used to
- later block/kill it.)
-*/
-extern nat vtalrm_id;
-TIMECALLBACK *vtalrm_cback;
-
+LPTIMECALLBACK vtalrm_cback;
+
nat
initialize_virtual_timer(nat ms)
{
- /* VTALRM is currently not supported by cygwin32,
- so we use the Timer support provided by the
- MultiMedia API that is part of Win32. The
- parameters to timeSetEvent may require some tweaking.
+ /* On Win32 setups that don't have support for
+ setitimer(), we use the MultiMedia API's timer
+ support.
+
+ The delivery of ticks isn't free; the performance hit should be checked.
*/
- unsigned int delay,vtalrm_id;
+ unsigned int delay;
+ static unsigned int vtalrm_id;
- delay = timeBeginPeriod(1);
- if (delay == TIMERR_NOCANDO) { /* error of some sort. */
- return delay;
+ if (ms) {
+ delay = timeBeginPeriod(1);
+ if (delay == TIMERR_NOCANDO) { /* error of some sort. */
+ return delay;
+ }
+ vtalrm_id =
+ timeSetEvent(ms, /* event every `delay' milliseconds. */
+ 1, /* precision is within 1 ms */
+ vtalrm_cback,
+ TIME_CALLBACK_FUNCTION, /* ordinary callback */
+ TIME_PERIODIC);
+ } else {
+ timeKillEvent(vtalrm_id);
+ timeEndPeriod(1);
}
- vtalrm_id =
- timeSetEvent(ms, /* event every `delay' milliseconds. */
- 1, /* precision is within 5 millisecs. */
- (LPTIMECALLBACK)vtalrm_cback,
- 0,
- TIME_PERIODIC);
+
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);
#if defined(mingw32_TARGET_OS) || (defined(cygwin32_TARGET_OS) && !defined(HAVE_SETITIMER))
int
-install_vtalrm_handler(void (*handler)(int))
+install_vtalrm_handler(void)
{
- vtalrm_cback = handler;
+ vtalrm_cback = handle_tick;
return 0;
}
#else
int
-install_vtalrm_handler(void (*handler)(int))
+install_vtalrm_handler(void)
{
struct sigaction action;
- action.sa_handler = handler;
+ action.sa_handler = handle_tick;
sigemptyset(&action.sa_mask);
action.sa_flags = 0;
(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.
+ */
+#if !defined(mingw32_TARGET_OS)
+unsigned int
+getourtimeofday(void)
+{
+ struct timeval tv;
+ gettimeofday(&tv, (struct timezone *) NULL);
+ return (tv.tv_sec * TICK_FREQUENCY +
+ tv.tv_usec * TICK_FREQUENCY / 1000000);
+}
+#else
+unsigned int
+getourtimeofday(void)
+{
+ return ((unsigned int)GetTickCount() * TICK_FREQUENCY) / 1000;
+}
+#endif