minix/lib/sysutil/sys_hz.c

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#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include <minix/u64.h>
#include <minix/config.h>
#include <minix/const.h>
#include "sysutil.h"
static u32_t Hz;
u32_t
sys_hz(void)
{
if(Hz <= 0) {
int r;
/* Get HZ. */
if((r=sys_getinfo(GET_HZ, &Hz, sizeof(Hz), 0, 0)) != OK) {
Hz = DEFAULT_HZ;
printf("sys_hz: %d: reverting to HZ = %d\n", r, Hz);
}
}
return Hz;
}
u32_t
micros_to_ticks(u32_t micros)
{
u32_t ticks;
ticks = div64u(mul64u(micros, sys_hz()), 1000000);
if(ticks < 1) ticks = 1;
return ticks;
}