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#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "ureg.h"
void (*kproftimer)(ulong);
typedef struct Clock0link Clock0link;
typedef struct Clock0link {
void (*clock)(void);
Clock0link* link;
} Clock0link;
static Clock0link *clock0link;
static Lock clock0lock;
void
addclock0link(void (*clock)(void))
{
Clock0link *lp;
if((lp = malloc(sizeof(Clock0link))) == 0){
print("addclock0link: too many links\n");
return;
}
ilock(&clock0lock);
lp->clock = clock;
lp->link = clock0link;
clock0link = lp;
iunlock(&clock0lock);
}
/*
* delay for l milliseconds more or less. delayloop is set by
* clockinit() to match the actual CPU speed.
*/
void
delay(int l)
{
ulong i, j;
j = m->delayloop;
while(l-- > 0)
for(i=0; i < j; i++)
;
}
void
clockinit(void)
{
long x;
m->delayloop = m->speed*100;
do {
x = rdcount();
delay(10);
x = rdcount() - x;
} while(x < 0);
/*
* fix count
*/
m->delayloop = (m->delayloop*m->speed*1000*10)/x;
if(m->delayloop == 0)
m->delayloop = 1;
wrcompare(rdcount()+(m->speed*1000000)/HZ);
}
void
clock(Ureg *ur)
{
Clock0link *lp;
wrcompare(rdcount()+(m->speed*1000000)/HZ);
m->ticks++;
if(m->proc)
m->proc->pc = ur->pc;
accounttime();
if(kproftimer != nil)
kproftimer(ur->pc);
kmapinval();
if((active.machs&(1<<m->machno)) == 0)
return;
if(active.exiting && (active.machs & (1<<m->machno))) {
print("someone's exiting\n");
exit(0);
}
checkalarms();
if(m->machno == 0){
lock(&clock0lock);
for(lp = clock0link; lp; lp = lp->link)
lp->clock();
unlock(&clock0lock);
}
if(up == 0 || up->state != Running)
return;
if(anyready())
sched();
/* user profiling clock */
if(ur->status & KUSER) {
(*(ulong*)(USTKTOP-BY2WD)) += TK2MS(1);
segclock(ur->pc);
}
}