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/*
* Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <stddef.h>
#include <errno.h>
#include <signal.h>
#include <time.h>
#include <sys/time.h>
#include "kern_constants.h"
#include "os.h"
#include "user.h"
static int is_real_timer = 0;
int set_interval(void)
{
int usec = 1000000/UM_HZ;
struct itimerval interval = ((struct itimerval) { { 0, usec },
{ 0, usec } });
if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1)
return -errno;
return 0;
}
void disable_timer(void)
{
struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }});
if ((setitimer(ITIMER_VIRTUAL, &disable, NULL) < 0) ||
(setitimer(ITIMER_REAL, &disable, NULL) < 0))
printk(UM_KERN_ERR "disable_timer - setitimer failed, "
"errno = %d\n", errno);
/* If there are signals already queued, after unblocking ignore them */
signal(SIGALRM, SIG_IGN);
signal(SIGVTALRM, SIG_IGN);
}
int switch_timers(int to_real)
{
struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }});
struct itimerval enable;
int old, new, old_type = is_real_timer;
if(to_real == old_type)
return to_real;
if (to_real) {
old = ITIMER_VIRTUAL;
new = ITIMER_REAL;
}
else {
old = ITIMER_REAL;
new = ITIMER_VIRTUAL;
}
if (setitimer(old, &disable, &enable) < 0)
printk(UM_KERN_ERR "switch_timers - setitimer disable failed, "
"errno = %d\n", errno);
if((enable.it_value.tv_sec == 0) && (enable.it_value.tv_usec == 0))
enable.it_value = enable.it_interval;
if (setitimer(new, &enable, NULL))
printk(UM_KERN_ERR "switch_timers - setitimer enable failed, "
"errno = %d\n", errno);
is_real_timer = to_real;
return old_type;
}
unsigned long long os_nsecs(void)
{
struct timeval tv;
gettimeofday(&tv, NULL);
return (unsigned long long) tv.tv_sec * BILLION + tv.tv_usec * 1000;
}
void idle_sleep(int secs)
{
struct timespec ts;
ts.tv_sec = secs;
ts.tv_nsec = 0;
nanosleep(&ts, NULL);
}
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