int
erts_port_task_schedule(Eterm id,
ErtsPortTaskHandle *pthp,
ErtsPortTaskType type,
ErlDrvEvent event,
ErlDrvEventData event_data)
{
ErtsRunQueue *runq;
Port *pp;
ErtsPortTask *ptp;
int enq_port = 0;
/*
* NOTE: We might not have the port lock here. We are only
* allowed to access the 'sched', 'tab_status',
* and 'id' fields of the port struct while
* tasks_lock is held.
*/
if (pthp && erts_port_task_is_scheduled(pthp)) {
ASSERT(0);
erts_port_task_abort(id, pthp);
}
ptp = port_task_alloc();
ASSERT(is_internal_port(id));
pp = &erts_port[internal_port_index(id)];
runq = erts_port_runq(pp);
if (!runq || ERTS_PORT_TASK_INVALID_PORT(pp, id)) {
if (runq)
erts_smp_runq_unlock(runq);
return -1;
}
ASSERT(!erts_port_task_is_scheduled(pthp));
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
if (!pp->sched.taskq) {
pp->sched.taskq = port_taskq_init(port_taskq_alloc(), pp);
enq_port = !pp->sched.exe_taskq;
}
#ifdef ERTS_SMP
if (enq_port) {
ErtsRunQueue *xrunq = erts_check_emigration_need(runq, ERTS_PORT_PRIO_LEVEL);
if (xrunq) {
/* Port emigrated ... */
erts_smp_atomic_set_nob(&pp->run_queue, (erts_aint_t) xrunq);
erts_smp_runq_unlock(runq);
runq = xrunq;
}
}
#endif
ASSERT(!enq_port || !(runq->flags & ERTS_RUNQ_FLG_SUSPENDED));
ASSERT(pp->sched.taskq);
ASSERT(ptp);
ptp->type = type;
ptp->event = event;
ptp->event_data = event_data;
set_handle(ptp, pthp);
switch (type) {
case ERTS_PORT_TASK_FREE:
erl_exit(ERTS_ABORT_EXIT,
"erts_port_task_schedule(): Cannot schedule free task\n");
break;
case ERTS_PORT_TASK_INPUT:
case ERTS_PORT_TASK_OUTPUT:
case ERTS_PORT_TASK_EVENT:
erts_smp_atomic_inc_relb(&erts_port_task_outstanding_io_tasks);
/* Fall through... */
default:
enqueue_task(pp->sched.taskq, ptp);
break;
}
#ifndef ERTS_SMP
/*
* When (!enq_port && !pp->sched.exe_taskq) is true in the smp case,
* the port might not be in the run queue. If this is the case, another
* thread is in the process of enqueueing the port. This very seldom
* occur, but do occur and is a valid scenario. Debug info showing this
* enqueue in progress must be introduced before we can enable (modified
* versions of these) assertions in the smp case again.
*/
#if defined(HARD_DEBUG)
if (pp->sched.exe_taskq || enq_port)
ERTS_PT_CHK_NOT_IN_PORTQ(runq, pp);
else
ERTS_PT_CHK_IN_PORTQ(runq, pp);
#elif defined(DEBUG)
if (!enq_port && !pp->sched.exe_taskq) {
/* We should be in port run q */
ASSERT(pp->sched.prev || runq->ports.start == pp);
}
#endif
#endif
if (!enq_port) {
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
erts_smp_runq_unlock(runq);
}
else {
enqueue_port(runq, pp);
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
if (erts_system_profile_flags.runnable_ports) {
profile_runnable_port(pp, am_active);
}
erts_smp_runq_unlock(runq);
erts_smp_notify_inc_runq(runq);
}
return 0;
}
void
erts_port_task_free_port(Port *pp)
{
ErtsRunQueue *runq;
int port_is_dequeued = 0;
ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
ASSERT(!(pp->status & ERTS_PORT_SFLGS_DEAD));
runq = erts_port_runq(pp);
ASSERT(runq);
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
if (pp->sched.exe_taskq) {
/* I (this thread) am currently executing this port, free it
when scheduled out... */
ErtsPortTask *ptp = port_task_alloc();
erts_smp_port_state_lock(pp);
pp->status &= ~ERTS_PORT_SFLG_CLOSING;
pp->status |= ERTS_PORT_SFLG_FREE_SCHEDULED;
erts_may_save_closed_port(pp);
erts_smp_port_state_unlock(pp);
ERTS_SMP_LC_ASSERT(erts_smp_atomic_read_nob(&pp->refc) > 1);
ptp->type = ERTS_PORT_TASK_FREE;
ptp->event = (ErlDrvEvent) -1;
ptp->event_data = NULL;
set_handle(ptp, NULL);
push_task(pp->sched.exe_taskq, ptp);
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
erts_smp_runq_unlock(runq);
}
else {
ErtsPortTaskQueue *ptqp = pp->sched.taskq;
if (ptqp) {
dequeue_port(runq, pp);
ERTS_PORT_NOT_IN_RUNQ(pp);
port_is_dequeued = 1;
}
erts_smp_port_state_lock(pp);
pp->status &= ~ERTS_PORT_SFLG_CLOSING;
pp->status |= ERTS_PORT_SFLG_FREE_SCHEDULED;
erts_may_save_closed_port(pp);
erts_smp_port_state_unlock(pp);
#ifdef ERTS_SMP
erts_smp_atomic_dec_nob(&pp->refc); /* Not alive */
#endif
ERTS_SMP_LC_ASSERT(erts_smp_atomic_read_nob(&pp->refc) > 0); /* Lock */
handle_remaining_tasks(runq, pp); /* May release runq lock */
ASSERT(!pp->sched.exe_taskq && (!ptqp || !ptqp->first));
pp->sched.taskq = NULL;
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
#ifndef ERTS_SMP
ASSERT(pp->status & ERTS_PORT_SFLG_PORT_DEBUG);
erts_port_status_set(pp, ERTS_PORT_SFLG_FREE);
#endif
erts_smp_runq_unlock(runq);
if (erts_system_profile_flags.runnable_ports && port_is_dequeued) {
profile_runnable_port(pp, am_inactive);
}
if (ptqp)
port_taskq_free(ptqp);
}
}
int
erts_port_task_schedule(Eterm id,
ErtsPortTaskHandle *pthp,
ErtsPortTaskType type,
ErlDrvEvent event,
ErlDrvEventData event_data)
{
ErtsRunQueue *runq;
Port *pp;
ErtsPortTask *ptp;
int enq_port = 0;
/*
* NOTE: We might not have the port lock here. We are only
* allowed to access the 'sched', 'tab_status',
* and 'id' fields of the port struct while
* tasks_lock is held.
*/
if (pthp && erts_port_task_is_scheduled(pthp)) {
ASSERT(0);
erts_port_task_abort(id, pthp);
}
ptp = port_task_alloc();
ASSERT(is_internal_port(id));
pp = &erts_port[internal_port_index(id)];
runq = erts_port_runq(pp);
if (!runq || ERTS_PORT_TASK_INVALID_PORT(pp, id)) {
if (runq)
erts_smp_runq_unlock(runq);
return -1;
}
ASSERT(!erts_port_task_is_scheduled(pthp));
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
#ifdef DEBUG
/* If we have a taskq and not executing, we should be in port run q */
if (pp->sched.taskq && !pp->sched.exe_taskq) {
ASSERT(pp->sched.prev || runq->ports.start == pp);
}
#endif
if (!pp->sched.taskq) {
pp->sched.taskq = port_taskq_init(port_taskq_alloc(), pp);
enq_port = !pp->sched.exe_taskq;
}
#ifdef ERTS_SMP
if (enq_port) {
ErtsRunQueue *xrunq = erts_check_emigration_need(runq, ERTS_PORT_PRIO_LEVEL);
if (xrunq) {
/* Port emigrated ... */
erts_smp_atomic_set(&pp->run_queue, (long) xrunq);
erts_smp_runq_unlock(runq);
runq = xrunq;
}
}
#endif
ASSERT(!(runq->flags & ERTS_RUNQ_FLG_SUSPENDED));
ASSERT(pp->sched.taskq);
ASSERT(ptp);
ptp->type = type;
ptp->event = event;
ptp->event_data = event_data;
set_handle(ptp, pthp);
switch (type) {
case ERTS_PORT_TASK_FREE:
erl_exit(ERTS_ABORT_EXIT,
"erts_port_task_schedule(): Cannot schedule free task\n");
break;
case ERTS_PORT_TASK_INPUT:
case ERTS_PORT_TASK_OUTPUT:
case ERTS_PORT_TASK_EVENT:
erts_smp_atomic_inc(&erts_port_task_outstanding_io_tasks);
/* Fall through... */
default:
enqueue_task(pp->sched.taskq, ptp);
break;
}
#if defined(HARD_DEBUG)
if (pp->sched.exe_taskq || enq_port)
ERTS_PT_CHK_NOT_IN_PORTQ(runq, pp);
else
ERTS_PT_CHK_IN_PORTQ(runq, pp);
#elif defined(DEBUG)
if (!enq_port && !pp->sched.exe_taskq) {
/* We should be in port run q */
ASSERT(pp->sched.prev || runq->ports.start == pp);
}
#endif
if (!enq_port) {
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
}
else {
enqueue_port(runq, pp);
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
if (erts_system_profile_flags.runnable_ports) {
profile_runnable_port(pp, am_active);
}
erts_smp_notify_inc_runq(runq);
}
erts_smp_runq_unlock(runq);
return 0;
}
