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This commit is contained in:
rsc 2006-06-26 05:47:59 +00:00
parent f936548b5e
commit df970459f9
6 changed files with 87 additions and 0 deletions
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52
src/libthread/thread.c
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@ -12,6 +12,7 @@ static void addproc(Proc*);
static void delproc(Proc*);
static void addthread(_Threadlist*, _Thread*);
static void delthread(_Threadlist*, _Thread*);
static int onlist(_Threadlist*, _Thread*);
static void addthreadinproc(Proc*, _Thread*);
static void delthreadinproc(Proc*, _Thread*);
static void contextswitch(Context *from, Context *to);
@ -254,6 +255,32 @@ threadexits(char *msg)
_threadswitch();
}
void
threadpin(void)
{
Proc *p;
p = proc();
if(p->pinthread){
fprint(2, "already pinning a thread - %p %p\n", p->pinthread, p->thread);
assert(0);
}
p->pinthread = p->thread;
}
void
threadunpin(void)
{
Proc *p;
p = proc();
if(p->pinthread != p->thread){
fprint(2, "wrong pinthread - %p %p\n", p->pinthread, p->thread);
assert(0);
}
p->pinthread = nil;
}
static void
contextswitch(Context *from, Context *to)
{
@ -273,6 +300,14 @@ procscheduler(Proc *p)
/* print("s %p\n", p); */
lock(&p->lock);
for(;;){
if((t = p->pinthread) != nil){
while(!onlist(&p->runqueue, t)){
p->runrend.l = &p->lock;
_threaddebug("scheduler sleep (pin)");
_procsleep(&p->runrend);
_threaddebug("scheduler wake (pin)");
}
}else
while((t = p->runqueue.head) == nil){
if(p->nthread == 0)
goto Out;
@ -291,6 +326,9 @@ procscheduler(Proc *p)
_procsleep(&p->runrend);
_threaddebug("scheduler wake");
}
if(p->pinthread && p->pinthread != t)
fprint(2, "p->pinthread %p t %p\n", p->pinthread, t);
assert(p->pinthread == nil || p->pinthread == t);
delthread(&p->runqueue, t);
unlock(&p->lock);
p->thread = t;
@ -652,6 +690,8 @@ main(int argc, char **argv)
_rsleep = threadrsleep;
_rwakeup = threadrwakeup;
_notejmpbuf = threadnotejmp;
_pin = threadpin;
_unpin = threadunpin;
_pthreadinit();
p = procalloc();
@ -697,6 +737,18 @@ delthread(_Threadlist *l, _Thread *t)
l->tail = t->prev;
}
/* inefficient but rarely used */
static int
onlist(_Threadlist *l, _Thread *t)
{
_Thread *tt;
for(tt = l->head; tt; tt=tt->next)
if(tt == t)
return 1;
return 0;
}
static void
addthreadinproc(Proc *p, _Thread *t)
{