diff options
Diffstat (limited to 'sys/kern/kern_synch.c')
| -rw-r--r-- | sys/kern/kern_synch.c | 182 |
1 files changed, 1 insertions, 181 deletions
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c index 9c52802..ad86cdb 100644 --- a/sys/kern/kern_synch.c +++ b/sys/kern/kern_synch.c @@ -403,12 +403,6 @@ msleep(ident, mtx, priority, wmesg, timo) KASSERT(p != NULL, ("msleep1")); KASSERT(ident != NULL && p->p_stat == SRUN, ("msleep")); - /* - * Process may be sitting on a slpque if asleep() was called, remove - * it before re-adding. - */ - if (p->p_wchan != NULL) - unsleep(p); p->p_wchan = ident; p->p_wmesg = wmesg; @@ -487,181 +481,7 @@ msleep(ident, mtx, priority, wmesg, timo) } /* - * asleep() - async sleep call. Place process on wait queue and return - * immediately without blocking. The process stays runnable until await() - * is called. If ident is NULL, remove process from wait queue if it is still - * on one. - * - * Only the most recent sleep condition is effective when making successive - * calls to asleep() or when calling msleep(). - * - * The timeout, if any, is not initiated until await() is called. The sleep - * priority, signal, and timeout is specified in the asleep() call but may be - * overriden in the await() call. - * - * <<<<<<<< EXPERIMENTAL, UNTESTED >>>>>>>>>> - */ - -int -asleep(void *ident, int priority, const char *wmesg, int timo) -{ - struct proc *p = curproc; - - /* - * Remove preexisting wait condition (if any) and place process - * on appropriate slpque, but do not put process to sleep. - */ - - mtx_lock_spin(&sched_lock); - - if (p->p_wchan != NULL) - unsleep(p); - - if (ident) { - p->p_wchan = ident; - p->p_wmesg = wmesg; - p->p_slptime = 0; - p->p_asleep.as_priority = priority; - p->p_asleep.as_timo = timo; - TAILQ_INSERT_TAIL(&slpque[LOOKUP(ident)], p, p_slpq); - } - - mtx_unlock_spin(&sched_lock); - - return(0); -} - -/* - * await() - wait for async condition to occur. The process blocks until - * wakeup() is called on the most recent asleep() address. If wakeup is called - * prior to await(), await() winds up being a NOP. - * - * If await() is called more then once (without an intervening asleep() call), - * await() is still effectively a NOP but it calls mi_switch() to give other - * processes some cpu before returning. The process is left runnable. - * - * <<<<<<<< EXPERIMENTAL, UNTESTED >>>>>>>>>> - */ - -int -await(int priority, int timo) -{ - struct proc *p = curproc; - int rval = 0; - - WITNESS_SLEEP(0, NULL); - mtx_lock_spin(&sched_lock); - if (cold || panicstr) { - /* - * After a panic, or during autoconfiguration, - * just give interrupts a chance, then just return; - * don't run any other procs or panic below, - * in case this is the idle process and already asleep. - */ - mtx_unlock_spin(&sched_lock); - return (0); - } - DROP_GIANT_NOSWITCH(); - - if (p->p_wchan != NULL) { - int sig; - int catch; - -#ifdef KTRACE - if (p && KTRPOINT(p, KTR_CSW)) - ktrcsw(p->p_tracep, 1, 0); -#endif - /* - * The call to await() can override defaults specified in - * the original asleep(). - */ - if (priority < 0) - priority = p->p_asleep.as_priority; - if (timo < 0) - timo = p->p_asleep.as_timo; - - /* - * Install timeout - */ - - if (timo) - callout_reset(&p->p_slpcallout, timo, endtsleep, p); - - sig = 0; - catch = priority & PCATCH; - - if (catch) { - p->p_sflag |= PS_SINTR; - mtx_unlock_spin(&sched_lock); - PROC_LOCK(p); - sig = CURSIG(p); - mtx_lock_spin(&sched_lock); - PROC_UNLOCK_NOSWITCH(p); - if (sig != 0) { - if (p->p_wchan) - unsleep(p); - } else if (p->p_wchan == NULL) - catch = 0; - } - if (p->p_wchan != NULL) { - p->p_stat = SSLEEP; - p->p_stats->p_ru.ru_nvcsw++; - mi_switch(); - } - KASSERT(p->p_stat == SRUN, ("running but not SRUN")); - p->p_sflag &= ~PS_SINTR; - if (p->p_sflag & PS_TIMEOUT) { - p->p_sflag &= ~PS_TIMEOUT; - if (sig == 0) - rval = EWOULDBLOCK; - } else if (timo) - callout_stop(&p->p_slpcallout); - mtx_unlock_spin(&sched_lock); - if (rval == 0 && catch) { - PROC_LOCK(p); - if (sig != 0 || (sig = CURSIG(p))) { - if (SIGISMEMBER(p->p_sigacts->ps_sigintr, sig)) - rval = EINTR; - else - rval = ERESTART; - } - PROC_UNLOCK(p); - } -#ifdef KTRACE - mtx_lock(&Giant); - if (KTRPOINT(p, KTR_CSW)) - ktrcsw(p->p_tracep, 0, 0); - mtx_unlock(&Giant); -#endif - } else { - /* - * If as_priority is 0, await() has been called without an - * intervening asleep(). We are still effectively a NOP, - * but we call mi_switch() for safety. - */ - - if (p->p_asleep.as_priority == 0) { - p->p_stats->p_ru.ru_nvcsw++; - mi_switch(); - } - mtx_unlock_spin(&sched_lock); - } - - /* - * clear p_asleep.as_priority as an indication that await() has been - * called. If await() is called again without an intervening asleep(), - * await() is still effectively a NOP but the above mi_switch() code - * is triggered as a safety. - */ - if (rval == 0) - p->p_asleep.as_priority = 0; - - PICKUP_GIANT(); - return (rval); -} - -/* - * Implement timeout for msleep or asleep()/await() + * Implement timeout for msleep() * * If process hasn't been awakened (wchan non-zero), * set timeout flag and undo the sleep. If proc |
