diff options
Diffstat (limited to 'src/lib9/qlock.c')
| -rw-r--r-- | src/lib9/qlock.c | 87 |
1 files changed, 49 insertions, 38 deletions
diff --git a/src/lib9/qlock.c b/src/lib9/qlock.c index d83a4b7f..798b08f3 100644 --- a/src/lib9/qlock.c +++ b/src/lib9/qlock.c @@ -16,13 +16,15 @@ enum Waking, }; -static ulong (*_rendezvousp)(ulong, ulong) = rendezvous; +static void (*procsleep)(_Procrend*) = _procsleep; +static void (*procwakeup)(_Procrend*) = _procwakeup; /* this gets called by the thread library ONLY to get us to use its rendezvous */ void -_qlockinit(ulong (*r)(ulong, ulong)) +_qlockinit(void (*sleep)(_Procrend*), void (*wakeup)(_Procrend*)) { - _rendezvousp = r; + procsleep = sleep; + procwakeup = wakeup; } /* find a free shared memory location to queue ourselves in */ @@ -39,7 +41,7 @@ getqlp(void) fprint(2, "qlock: out of qlp\n"); abort(); } - if(_tas(&(p->inuse)) == 0){ + if(canlock(&p->inuse)){ ql.p = p; p->next = nil; break; @@ -70,13 +72,11 @@ qlock(QLock *q) p->next = mp; q->tail = mp; mp->state = Queuing; + mp->rend.l = &q->lock; + _procsleep(&mp->rend); unlock(&q->lock); - - /* wait */ - while((*_rendezvousp)((ulong)mp, 1) == ~0) - ; assert(mp->state == Waking); - mp->inuse = 0; + unlock(&mp->inuse); } void @@ -91,10 +91,9 @@ qunlock(QLock *q) q->head = p->next; if(q->head == nil) q->tail = nil; - unlock(&q->lock); p->state = Waking; - while((*_rendezvousp)((ulong)p, 0x12345) == ~0) - ; + _procwakeup(&p->rend); + unlock(&q->lock); return; } q->locked = 0; @@ -137,13 +136,11 @@ rlock(RWLock *q) q->tail = mp; mp->next = nil; mp->state = QueuingR; + mp->rend.l = &q->lock; + _procsleep(&mp->rend); unlock(&q->lock); - - /* wait in kernel */ - while((*_rendezvousp)((ulong)mp, 1) == ~0) - ; assert(mp->state == Waking); - mp->inuse = 0; + unlock(&mp->inuse); } int @@ -181,12 +178,11 @@ runlock(RWLock *q) if(q->head == 0) q->tail = 0; q->writer = 1; - unlock(&q->lock); /* wakeup waiter */ p->state = Waking; - while((*_rendezvousp)((ulong)p, 0) == ~0) - ; + _procwakeup(&p->rend); + unlock(&q->lock); } void @@ -212,13 +208,13 @@ wlock(RWLock *q) q->tail = mp; mp->next = nil; mp->state = QueuingW; - unlock(&q->lock); /* wait in kernel */ - while((*_rendezvousp)((ulong)mp, 1) == ~0) - ; + mp->rend.l = &q->lock; + _procsleep(&mp->rend); + unlock(&q->lock); assert(mp->state == Waking); - mp->inuse = 0; + unlock(&mp->inuse); } int @@ -256,10 +252,9 @@ wunlock(RWLock *q) q->head = p->next; if(q->head == nil) q->tail = nil; - unlock(&q->lock); p->state = Waking; - while((*_rendezvousp)((ulong)p, 0) == ~0) - ; + _procwakeup(&p->rend); + unlock(&q->lock); return; } @@ -274,8 +269,7 @@ wunlock(RWLock *q) q->head = p->next; q->readers++; p->state = Waking; - while((*_rendezvousp)((ulong)p, 0) == ~0) - ; + _procwakeup(&p->rend); } if(q->head == nil) q->tail = nil; @@ -315,20 +309,17 @@ rsleep(Rendez *r) r->l->head = t->next; if(r->l->head == nil) r->l->tail = nil; - unlock(&r->l->lock); t->state = Waking; - while((*_rendezvousp)((ulong)t, 0x12345) == ~0) - ; - }else{ + _procwakeup(&t->rend); + }else r->l->locked = 0; - unlock(&r->l->lock); - } /* wait for a wakeup */ - while((*_rendezvousp)((ulong)me, 0x23456) == ~0) - ; + me->rend.l = &r->l->lock; + _procsleep(&me->rend); + assert(me->state == Waking); - me->inuse = 0; + unlock(&me->inuse); if(!r->l->locked){ fprint(2, "rsleep: not locked after wakeup\n"); abort(); @@ -384,3 +375,23 @@ rwakeupall(Rendez *r) ; return i; } + +void +_procsleep(_Procrend *rend) +{ +//print("sleep %p %d\n", rend, getpid()); + pthread_cond_init(&rend->cond, 0); + rend->asleep = 1; + while(rend->asleep) + pthread_cond_wait(&rend->cond, &rend->l->mutex); + pthread_cond_destroy(&rend->cond); +} + +void +_procwakeup(_Procrend *rend) +{ +//print("wakeup %p\n", rend); + rend->asleep = 0; + pthread_cond_signal(&rend->cond); +} + |