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;
}
int
erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
{
int port_was_enqueued = 0;
Port *pp;
ErtsPortTaskQueue *ptqp;
ErtsPortTask *ptp;
int res = 0;
int reds = ERTS_PORT_REDS_EXECUTE;
erts_aint_t io_tasks_executed = 0;
int fpe_was_unmasked;
ErtsPortTaskExeBlockData blk_data = {runq, NULL};
ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
ERTS_PT_CHK_PORTQ(runq);
pp = pop_port(runq);
if (!pp) {
res = 0;
goto done;
}
ERTS_PORT_NOT_IN_RUNQ(pp);
*curr_port_pp = pp;
ASSERT(pp->sched.taskq);
ASSERT(pp->sched.taskq->first);
ptqp = pp->sched.taskq;
pp->sched.taskq = NULL;
ASSERT(!pp->sched.exe_taskq);
pp->sched.exe_taskq = ptqp;
if (erts_smp_port_trylock(pp) == EBUSY) {
erts_smp_runq_unlock(runq);
erts_smp_port_lock(pp);
erts_smp_runq_lock(runq);
}
if (erts_sched_stat.enabled) {
ErtsSchedulerData *esdp = erts_get_scheduler_data();
Uint old = ERTS_PORT_SCHED_ID(pp, esdp->no);
int migrated = old && old != esdp->no;
erts_smp_spin_lock(&erts_sched_stat.lock);
erts_sched_stat.prio[ERTS_PORT_PRIO_LEVEL].total_executed++;
erts_sched_stat.prio[ERTS_PORT_PRIO_LEVEL].executed++;
if (migrated) {
erts_sched_stat.prio[ERTS_PORT_PRIO_LEVEL].total_migrated++;
erts_sched_stat.prio[ERTS_PORT_PRIO_LEVEL].migrated++;
}
erts_smp_spin_unlock(&erts_sched_stat.lock);
}
/* trace port scheduling, in */
if (IS_TRACED_FL(pp, F_TRACE_SCHED_PORTS)) {
trace_sched_ports(pp, am_in);
}
ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
ptp = pop_task(ptqp);
fpe_was_unmasked = erts_block_fpe();
while (ptp) {
ASSERT(pp->sched.taskq != pp->sched.exe_taskq);
reset_handle(ptp);
erts_smp_runq_unlock(runq);
ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
ERTS_SMP_CHK_NO_PROC_LOCKS;
ASSERT(pp->drv_ptr);
switch (ptp->type) {
case ERTS_PORT_TASK_FREE: /* May be pushed in q at any time */
reds += ERTS_PORT_REDS_FREE;
erts_smp_runq_lock(runq);
erts_unblock_fpe(fpe_was_unmasked);
ASSERT(pp->status & ERTS_PORT_SFLG_FREE_SCHEDULED);
if (ptqp->first || (pp->sched.taskq && pp->sched.taskq->first))
handle_remaining_tasks(runq, pp);
ASSERT(!ptqp->first
&& (!pp->sched.taskq || !pp->sched.taskq->first));
#ifdef ERTS_SMP
erts_smp_atomic_dec_nob(&pp->refc); /* Not alive */
ERTS_SMP_LC_ASSERT(erts_smp_atomic_read_nob(&pp->refc) > 0); /* Lock */
#else
erts_port_status_bor_set(pp, ERTS_PORT_SFLG_FREE);
#endif
port_task_free(ptp);
if (pp->sched.taskq)
port_taskq_free(pp->sched.taskq);
pp->sched.taskq = NULL;
goto tasks_done;
case ERTS_PORT_TASK_TIMEOUT:
reds += ERTS_PORT_REDS_TIMEOUT;
if (!(pp->status & ERTS_PORT_SFLGS_DEAD))
(*pp->drv_ptr->timeout)((ErlDrvData) pp->drv_data);
break;
case ERTS_PORT_TASK_INPUT:
reds += ERTS_PORT_REDS_INPUT;
ASSERT((pp->status & ERTS_PORT_SFLGS_DEAD) == 0);
/* NOTE some windows drivers use ->ready_input for input and output */
(*pp->drv_ptr->ready_input)((ErlDrvData) pp->drv_data, ptp->event);
io_tasks_executed++;
break;
case ERTS_PORT_TASK_OUTPUT:
reds += ERTS_PORT_REDS_OUTPUT;
ASSERT((pp->status & ERTS_PORT_SFLGS_DEAD) == 0);
(*pp->drv_ptr->ready_output)((ErlDrvData) pp->drv_data, ptp->event);
io_tasks_executed++;
break;
case ERTS_PORT_TASK_EVENT:
reds += ERTS_PORT_REDS_EVENT;
ASSERT((pp->status & ERTS_PORT_SFLGS_DEAD) == 0);
(*pp->drv_ptr->event)((ErlDrvData) pp->drv_data, ptp->event, ptp->event_data);
io_tasks_executed++;
break;
case ERTS_PORT_TASK_DIST_CMD:
reds += erts_dist_command(pp, CONTEXT_REDS-reds);
break;
default:
erl_exit(ERTS_ABORT_EXIT,
"Invalid port task type: %d\n",
(int) ptp->type);
break;
}
if ((pp->status & ERTS_PORT_SFLG_CLOSING)
&& erts_is_port_ioq_empty(pp)) {
reds += ERTS_PORT_REDS_TERMINATE;
erts_terminate_port(pp);
}
ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
#ifdef ERTS_SMP
if (pp->xports)
erts_smp_xports_unlock(pp);
ASSERT(!pp->xports);
#endif
ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(pp));
port_task_free(ptp);
erts_smp_runq_lock(runq);
ptp = pop_task(ptqp);
}
tasks_done:
erts_unblock_fpe(fpe_was_unmasked);
if (io_tasks_executed) {
ASSERT(erts_smp_atomic_read_nob(&erts_port_task_outstanding_io_tasks)
>= io_tasks_executed);
erts_smp_atomic_add_relb(&erts_port_task_outstanding_io_tasks,
-1*io_tasks_executed);
}
*curr_port_pp = NULL;
#ifdef ERTS_SMP
ASSERT(runq == (ErtsRunQueue *) erts_smp_atomic_read_nob(&pp->run_queue));
#endif
if (!pp->sched.taskq) {
ASSERT(pp->sched.exe_taskq);
pp->sched.exe_taskq = NULL;
}
else {
#ifdef ERTS_SMP
ErtsRunQueue *xrunq;
#endif
ASSERT(!(pp->status & ERTS_PORT_SFLGS_DEAD));
ASSERT(pp->sched.taskq->first);
#ifdef ERTS_SMP
xrunq = erts_check_emigration_need(runq, ERTS_PORT_PRIO_LEVEL);
if (!xrunq) {
#endif
enqueue_port(runq, pp);
ASSERT(pp->sched.exe_taskq);
pp->sched.exe_taskq = NULL;
/* No need to notify ourselves about inc in runq. */
#ifdef ERTS_SMP
}
else {
/* Port emigrated ... */
erts_smp_atomic_set_nob(&pp->run_queue, (erts_aint_t) xrunq);
enqueue_port(xrunq, pp);
ASSERT(pp->sched.exe_taskq);
pp->sched.exe_taskq = NULL;
erts_smp_runq_unlock(xrunq);
erts_smp_notify_inc_runq(xrunq);
}
#endif
port_was_enqueued = 1;
}
res = (erts_smp_atomic_read_nob(&erts_port_task_outstanding_io_tasks)
!= (erts_aint_t) 0);
ERTS_PT_CHK_PRES_PORTQ(runq, pp);
port_taskq_free(ptqp);
if (erts_system_profile_flags.runnable_ports && (port_was_enqueued != 1)) {
profile_runnable_port(pp, am_inactive);
}
/* trace port scheduling, out */
if (IS_TRACED_FL(pp, F_TRACE_SCHED_PORTS)) {
trace_sched_ports(pp, am_out);
}
#ifndef ERTS_SMP
erts_port_release(pp);
#else
{
erts_aint_t refc;
erts_smp_mtx_unlock(pp->lock);
refc = erts_smp_atomic_dec_read_nob(&pp->refc);
ASSERT(refc >= 0);
if (refc == 0) {
erts_smp_runq_unlock(runq);
erts_port_cleanup(pp); /* Might aquire runq lock */
erts_smp_runq_lock(runq);
res = (erts_smp_atomic_read_nob(&erts_port_task_outstanding_io_tasks)
!= (erts_aint_t) 0);
}
}
#endif
done:
blk_data.resp = &res;
ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
ERTS_PORT_REDUCTIONS_EXECUTED(runq, reds);
return res;
}
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;
}