Example #1
0
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;
}
Example #2
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;
}
Example #3
0
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;
}