static void
rebalance(void)
{
int pri, npri, t, x;
Schedq *rq;
Proc *p;
t = m->ticks;
if(t - balancetime < HZ)
return;
balancetime = t;
for(pri=0, rq=runq; pri<Npriq; pri++, rq++){
another:
p = rq->head;
if(p == nil)
continue;
if(p->mp != MACHP(m->machno))
continue;
if(pri == p->basepri)
continue;
updatecpu(p);
npri = reprioritize(p);
if(npri != pri){
x = splhi();
p = dequeueproc(rq, p);
if(p != nil)
queueproc(&runq[npri], p);
splx(x);
goto another;
}
}
}
/*
* recalculate priorities once a second. We need to do this
* since priorities will otherwise only be recalculated when
* the running process blocks.
*/
static void
rebalance(void)
{
Mach *m = machp();
Mpl pl;
int pri, npri, t;
Schedq *rq;
Proc *p;
t = m->ticks;
if(t - run.balancetime < HZ)
return;
run.balancetime = t;
for(pri=0, rq=run.runq; pri<Npriq; pri++, rq++){
another:
p = rq->head;
if(p == nil)
continue;
if(p->mp != sys->machptr[m->machno]) //MACHP(m->machno)
continue;
if(pri == p->basepri)
continue;
updatecpu(p);
npri = reprioritize(p);
if(npri != pri){
pl = splhi();
p = dequeueproc(&run, rq, p);
if(p)
queueproc(&run, &run.runq[npri], p, 0);
splx(pl);
goto another;
}
}
}
static void
releaseintr(Ureg*, Timer *t)
{
Proc *p;
extern int panicking;
Schedq *rq;
if(panicking || active.exiting)
return;
p = t->ta;
if((edflock(p)) == nil)
return;
DPRINT("%lud releaseintr %d[%s]\n", now, p->pid, statename[p->state]);
switch(p->state){
default:
edfunlock();
return;
case Ready:
/* remove proc from current runq */
rq = &runq[p->priority];
if(dequeueproc(rq, p) != p){
DPRINT("releaseintr: can't find proc or lock race\n");
release(p); /* It'll start best effort */
edfunlock();
return;
}
p->state = Waitrelease;
/* fall through */
case Waitrelease:
release(p);
edfunlock();
if(p->state == Wakeme){
iprint("releaseintr: wakeme\n");
}
ready(p);
if(up){
up->delaysched++;
delayedscheds++;
}
return;
case Running:
release(p);
edfrun(p, 1);
break;
case Wakeme:
release(p);
edfunlock();
if(p->trend)
wakeup(p->trend);
p->trend = nil;
if(up){
up->delaysched++;
delayedscheds++;
}
return;
}
edfunlock();
}
/*
* SMP performs better than AMP with few cores.
* So, leave this here by now. We should probably
* write a unified version of runproc good enough for
* both SMP and AMP.
*/
static Proc*
smprunproc(void)
{
Mach *m = machp();
Schedq *rq;
Proc *p;
uint32_t start, now;
int i;
start = perfticks();
run.preempts++;
loop:
/*
* find a process that last ran on this processor (affinity),
* or one that hasn't moved in a while (load balancing). Every
* time around the loop affinity goes down.
*/
spllo();
for(i = 0;; i++){
/*
* find the highest priority target process that this
* processor can run given affinity constraints.
*
*/
for(rq = &run.runq[Nrq-1]; rq >= run.runq; rq--){
for(p = rq->head; p; p = p->rnext){
if(p->mp == nil || p->mp == sys->machptr[m->machno]
|| (!p->wired && i > 0))
goto found;
}
}
/* waste time or halt the CPU */
idlehands();
/* remember how much time we're here */
now = perfticks();
m->perf.inidle += now-start;
start = now;
}
found:
splhi();
p = dequeueproc(&run, rq, p);
if(p == nil)
goto loop;
p->state = Scheding;
p->mp = sys->machptr[m->machno];
if(edflock(p)){
edfrun(p, rq == &run.runq[PriEdf]); /* start deadline timer and do admin */
edfunlock();
}
if(p->trace)
proctrace(p, SRun, 0);
return p;
}
/*
* pick a process to run
*/
Proc*
runproc(void)
{
Schedq *rq;
Proc *p;
ulong start, now;
int i;
void (*pt)(Proc*, int, vlong);
start = perfticks();
/* cooperative scheduling until the clock ticks */
if((p = m->readied) != nil && p->mach == nil && p->state == Ready
&& (p->wired == nil || p->wired == MACHP(m->machno))
&& runq[Nrq-1].head == nil && runq[Nrq-2].head == nil){
skipscheds++;
rq = &runq[p->priority];
goto found;
}
preempts++;
loop:
/*
* find a process that last ran on this processor (affinity),
* or one that hasn't moved in a while (load balancing). Every
* time around the loop affinity goes down.
*/
spllo();
for(i = 0;; i++){
/*
* find the highest priority target process that this
* processor can run given affinity constraints.
*
*/
for(rq = &runq[Nrq-1]; rq >= runq; rq--){
for(p = rq->head; p != nil; p = p->rnext){
if(p->mp == nil || p->mp == MACHP(m->machno)
|| (p->wired == nil && i > 0))
goto found;
}
}
/* waste time or halt the CPU */
idlehands();
/* remember how much time we're here */
now = perfticks();
m->perf.inidle += now-start;
start = now;
}
found:
splhi();
p = dequeueproc(rq, p);
if(p == nil)
goto loop;
p->state = Scheding;
p->mp = MACHP(m->machno);
if(edflock(p)){
edfrun(p, rq == &runq[PriEdf]); /* start deadline timer and do admin */
edfunlock();
}
pt = proctrace;
if(pt != nil)
pt(p, SRun, 0);
return p;
}
static Proc*
singlerunproc(void)
{
Mach *m = machp();
Schedq *rq;
Proc *p;
uint32_t start, now, skipscheds;
int i;
start = perfticks();
/* cooperative scheduling until the clock ticks */
if((p=m->readied) && p->mach==0 && p->state==Ready
&& &run.runq[Nrq-1].head == nil && &run.runq[Nrq-2].head == nil){
skipscheds++;
rq = &run.runq[p->priority];
if(0)hi("runproc going to found before loop...\n");
goto found;
}
run.preempts++;
loop:
/*
* find a process that last ran on this processor (affinity),
* or one that hasn't moved in a while (load balancing). Every
* time around the loop affinity goes down.
*/
spllo();
for(i = 0;; i++){
/*
* find the highest priority target process that this
* processor can run given affinity constraints.
*
*/
for(rq = &run.runq[Nrq-1]; rq >= run.runq; rq--){
for(p = rq->head; p; p = p->rnext){
if(p->mp == nil || p->mp == sys->machptr[m->machno]
|| (!p->wired && i > 0))
{
if(0)hi("runproc going to found inside loop...\n");
goto found;
}
}
}
/* waste time or halt the CPU */
idlehands();
/* remember how much time we're here */
now = perfticks();
m->perf.inidle += now-start;
start = now;
}
found:
splhi();
if(0)hi("runproc into found...\n");
p = dequeueproc(&run, rq, p);
if(p == nil)
{
if(0)hi("runproc p=nil :(\n");
goto loop;
}
p->state = Scheding;
if(0)hi("runproc, pm->mp = sys->machptr[m->machno]\n");
p->mp = sys->machptr[m->machno];
if(0){hi("runproc, sys->machptr[m->machno] = "); put64((uint64_t)p->mp); hi("\n");}
if(edflock(p)){
edfrun(p, rq == &run.runq[PriEdf]); /* start deadline timer and do admin */
edfunlock();
}
if(p->trace)
proctrace(p, SRun, 0);
/* avoiding warnings, this will be removed */
USED(mach0sched); USED(smprunproc);
if(0){hi("runproc, returning p ");
put64((uint64_t)p);
hi("\n");}
return p;
}
/*
* Scheduling thread run as the main loop of cpu 0
* Used in AMP sched.
*/
static void
mach0sched(void)
{
Mach *m = machp();
Schedq *rq;
Proc *p;
Mach *mp;
uint32_t start, now;
int n, i; //, j;
assert(m->machno == 0);
acmodeset(NIXKC); /* we don't time share any more */
n = 0;
start = perfticks();
loop:
/*
* find a ready process that we might run.
*/
spllo();
for(rq = &run.runq[Nrq-1]; rq >= run.runq; rq--)
for(p = rq->head; p; p = p->rnext){
/*
* wired processes may only run when their core is available.
*/
if(p->wired != nil){
if(p->wired->proc == nil)
goto found;
continue;
}
/*
* find a ready process that did run at an available core
* or one that has not moved for some time.
*/
if(p->mp == nil || p->mp->proc == nil || n>0){
goto found;
}
}
/* waste time or halt the CPU */
idlehands();
/* remember how much time we're here */
now = perfticks();
m->perf.inidle += now-start;
start = now;
n++;
goto loop;
found:
assert(m->machno == 0);
splhi();
/*
* find a core for this process, but honor wiring.
*/
mp = p->wired;
if(mp != nil){
if(mp->proc != nil)
goto loop;
}else{
for(i = 0; i < MACHMAX; i++){
/*j = pickcore(p->color, i);
if((mp = sys->machptr[j]) != nil && mp->online && mp->nixtype == NIXTC){*/
if((mp = sys->machptr[i]) != nil){ // && mp->online && mp->nixtype == NIXTC){
if(mp != m && mp->proc == nil)
break;
}
}
if(i == MACHMAX){
preemptfor(p);
goto loop;
}
}
p = dequeueproc(&run, rq, p);
mp->proc = p;
if(p != nil){
p->state = Scheding;
p->mp = mp;
}
n = 0;
goto loop;
}
