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;
}
Proc*
runproc(void)
{
Mach *m = machp();
Schedq *rq;
Proc *p;
uint32_t start, now;
if(nosmp)
return singlerunproc();
//NIX modeset cannot work without halt every cpu at boot
//if(sys->nmach <= AMPmincores)
else
return smprunproc();
start = perfticks();
run.preempts++;
rq = nil;
if(m->machno != 0){
do{
spllo();
while(m->proc == nil)
idlehands();
now = perfticks();
m->perf.inidle += now-start;
start = now;
splhi();
p = m->proc;
}while(p == nil);
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;
}
mach0sched();
return nil; /* not reached */
}
/*
* 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;
}
char *
edfadmit(Proc *p)
{
Proc *up = externup();
char *err;
Edf *e;
int i;
Proc *r;
int32_t tns;
e = p->edf;
if (e->flags & Admitted)
return "task state"; /* should never happen */
/* simple sanity checks */
if (e->T == 0)
return "T not set";
if (e->C == 0)
return "C not set";
if (e->D > e->T)
return "D > T";
if (e->D == 0) /* if D is not set, set it to T */
e->D = e->T;
if (e->C > e->D)
return "C > D";
qlock(&edfschedlock);
if (err = testschedulability(p)){
qunlock(&edfschedlock);
return err;
}
e->flags |= Admitted;
edflock(p);
if(p->trace)
proctrace(p, SAdmit, 0);
/* Look for another proc with the same period to synchronize to */
for(i=0; (r = psincref(i)) != nil; i++) {
if(r->state == Dead || r == p){
psdecref(r);
continue;
}
if (r->edf == nil || (r->edf->flags & Admitted) == 0){
psdecref(r);
continue;
}
if (r->edf->T == e->T)
break;
}
if (r == nil){
/* Can't synchronize to another proc, release now */
e->t = now;
e->d = 0;
release(p);
if (p == up){
DPRINT("%lu edfadmit self %d[%s], release now: r=%lu d=%lu t=%lu\n",
now, p->pid, statename[p->state], e->r, e->d, e->t);
/* We're already running */
edfrun(p, 1);
}else{
/* We're releasing another proc */
DPRINT("%lu edfadmit other %d[%s], release now: r=%lu d=%lu t=%lu\n",
now, p->pid, statename[p->state], e->r, e->d, e->t);
p->Timer.ta = p;
edfunlock();
qunlock(&edfschedlock);
releaseintr(nil, &p->Timer);
return nil;
}
}else{
/* Release in synch to something else */
e->t = r->edf->t;
psdecref(r);
if (p == up){
DPRINT("%lu edfadmit self %d[%s], release at %lu\n",
now, p->pid, statename[p->state], e->t);
}else{
DPRINT("%lu edfadmit other %d[%s], release at %lu\n",
now, p->pid, statename[p->state], e->t);
if(e->Timer.tt == nil){
e->Timer.tf = releaseintr;
e->Timer.ta = p;
tns = e->t - now;
if(tns < 20)
tns = 20;
e->Timer.tns = 1000LL * tns;
e->Timer.tmode = Trelative;
timeradd(&e->Timer);
}
}
}
edfunlock();
qunlock(&edfschedlock);
return nil;
}
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;
}
char *
edfadmit(Proc *p)
{
char *err;
Edf *e;
int i;
Proc *r;
void (*pt)(Proc*, int, vlong);
e = p->edf;
if (e->flags & Admitted)
return "task state"; /* should never happen */
/* simple sanity checks */
if (e->T == 0)
return "T not set";
if (e->C == 0)
return "C not set";
if (e->D > e->T)
return "D > T";
if (e->D == 0) /* if D is not set, set it to T */
e->D = e->T;
if (e->C > e->D)
return "C > D";
qlock(&edfschedlock);
if (err = testschedulability(p)){
qunlock(&edfschedlock);
return err;
}
e->flags |= Admitted;
edflock(p);
if(pt = proctrace)
pt(p, SAdmit, now);
/* Look for another proc with the same period to synchronize to */
SET(r);
for(i=0; i<conf.nproc; i++) {
r = proctab(i);
if(r->state == Dead || r == p)
continue;
if (r->edf == nil || (r->edf->flags & Admitted) == 0)
continue;
if (r->edf->T == e->T)
break;
}
if (i == conf.nproc){
/* Can't synchronize to another proc, release now */
e->t = now;
e->d = 0;
release(p);
if (p == up){
DPRINT("%t edfadmit self %lud[%s], release now: r=%t d=%t t=%t\n",
now, p->pid, statename[p->state], e->r, e->d, e->t);
/* We're already running */
edfrun(p, 1);
}else{
/* We're releasing another proc */
DPRINT("%t edfadmit other %lud[%s], release now: r=%t d=%t t=%t\n",
now, p->pid, statename[p->state], e->r, e->d, e->t);
p->ta = p;
edfunlock();
qunlock(&edfschedlock);
releaseintr(nil, p);
return nil;
}
}else{
/* Release in synch to something else */
e->t = r->edf->t;
if (p == up){
DPRINT("%t edfadmit self %lud[%s], release at %t\n",
now, p->pid, statename[p->state], e->t);
edfunlock();
qunlock(&edfschedlock);
return nil;
}else{
DPRINT("%t edfadmit other %lud[%s], release at %t\n",
now, p->pid, statename[p->state], e->t);
if(e->tt == nil){
e->tf = releaseintr;
e->ta = p;
e->tns = e->t;
e->tmode = Tabsolute;
timeradd(e);
}
}
}
edfunlock();
qunlock(&edfschedlock);
return nil;
}