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Print Linux Kernel Frequency
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#define USECREQ 250
#define LOOPS 1000
void event_handler (int signum)
{
static unsigned long cnt = 0;
static struct timeval tsFirst;
if (cnt == 0) {
gettimeofday (&tsFirst, 0);
}
cnt ++;
if (cnt >= LOOPS) {
struct timeval tsNow;
struct timeval diff;
setitimer (ITIMER_REAL, NULL, NULL);
gettimeofday (&tsNow, 0);
timersub(&tsNow, &tsFirst, &diff);
unsigned long long udiff = (diff.tv_sec * 1000000) + diff.tv_usec;
double delta = (double)(udiff/cnt)/1000000;
int hz = (unsigned)(1.0/delta);
printf ("kernel timer interrupt frequency is approx. %d Hz", hz);
if (hz >= (int) (1.0/((double)(USECREQ)/1000000))) {
printf (" or higher");
}
printf ("\n");
exit (0);
}
}
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