starpu-max/src/core/workers.c

/* StarPU --- Runtime system for heterogeneous multicore architectures.
 *
 * Copyright (C) 2009-2015  Université de Bordeaux
 * Copyright (C) 2010, 2011, 2012, 2013, 2014, 2015  CNRS
 * Copyright (C) 2010, 2011  INRIA
 * Copyright (C) 2011  Télécom-SudParis
 * Copyright (C) 2011-2012  INRIA
 *
 * StarPU is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or (at
 * your option) any later version.
 *
 * StarPU is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU Lesser General Public License in COPYING.LGPL for more details.
 */

#include <stdlib.h>
#include <stdio.h>
#include <common/config.h>
#include <common/utils.h>
#include <core/progress_hook.h>
#include <core/workers.h>
#include <core/debug.h>
#include <core/disk.h>
#include <core/task.h>
#include <datawizard/malloc.h>
#include <profiling/profiling.h>
#include <starpu_task_list.h>
#include <sched_policies/sched_component.h>
#include <datawizard/memory_nodes.h>
#include <drivers/mp_common/sink_common.h>
#include <drivers/scc/driver_scc_common.h>

#include <drivers/cpu/driver_cpu.h>
#include <drivers/cuda/driver_cuda.h>
#include <drivers/opencl/driver_opencl.h>

#ifdef STARPU_SIMGRID
#include <core/simgrid.h>
#endif

#if defined(_WIN32) && !defined(__CYGWIN__)
#include <windows.h>
#endif

/* acquire/release semantic for concurrent initialization/de-initialization */
static starpu_pthread_mutex_t init_mutex = STARPU_PTHREAD_MUTEX_INITIALIZER;
static starpu_pthread_cond_t init_cond = STARPU_PTHREAD_COND_INITIALIZER;
static int init_count = 0;
static enum { UNINITIALIZED, CHANGING, INITIALIZED } initialized = UNINITIALIZED;

static starpu_pthread_key_t worker_key;
static starpu_pthread_key_t worker_set_key;

static struct _starpu_machine_config config;

/* Pointers to argc and argv
 */
static int *my_argc = 0;
static char ***my_argv = NULL;

/* Initialize value of static argc and argv, called when the process begins
 */
void _starpu_set_argc_argv(int *argc_param, char ***argv_param)
{
	my_argc = argc_param;
	my_argv = argv_param;
}

int *_starpu_get_argc()
{
	return my_argc;
}

char ***_starpu_get_argv()
{
	return my_argv;
}

int _starpu_is_initialized(void)
{
	return initialized == INITIALIZED;
}

struct _starpu_machine_config *_starpu_get_machine_config(void)
{
	return &config;
}

/* Makes sure that at least one of the workers of type <arch> can execute
 * <task>, for at least one of its implementations. */
static uint32_t _starpu_worker_exists_and_can_execute(struct starpu_task *task,
						      enum starpu_worker_archtype arch)
{
	int i;
	_starpu_codelet_check_deprecated_fields(task->cl);

        /* make sure there is a worker on the machine able to execute the
	   task, independent of the sched_ctx, this latter may receive latter on
	   the necessary worker - the user or the hypervisor should take care this happens */

	int check_entire_platform = starpu_get_env_number("STARPU_CHECK_ENTIRE_PLATFORM");
	struct _starpu_sched_ctx *sched_ctx = check_entire_platform == 1 ? _starpu_get_initial_sched_ctx() : _starpu_get_sched_ctx_struct(task->sched_ctx);
	struct starpu_worker_collection *workers = sched_ctx->workers;
	struct starpu_sched_ctx_iterator it;
	workers->init_iterator(workers, &it);
	while(workers->has_next(workers, &it))
	{
		i = workers->get_next(workers, &it);
		if (starpu_worker_get_type(i) != arch)
			continue;

		unsigned impl;
		for (impl = 0; impl < STARPU_MAXIMPLEMENTATIONS; impl++)
		{
			/* We could call task->cl->can_execute(i, task, impl)
			   here, it would definitely work. It is probably
			   cheaper to check whether it is necessary in order to
			   avoid a useless function call, though. */
			unsigned test_implementation = 0;
			switch (arch)
			{
			case STARPU_CPU_WORKER:
				if (task->cl->cpu_funcs[impl] != NULL)
					test_implementation = 1;
				break;
			case STARPU_CUDA_WORKER:
				if (task->cl->cuda_funcs[impl] != NULL)
					test_implementation = 1;
				break;
			case STARPU_OPENCL_WORKER:
				if (task->cl->opencl_funcs[impl] != NULL)
					test_implementation = 1;
				break;
			case STARPU_MIC_WORKER:
				if (task->cl->cpu_funcs_name[impl] != NULL || task->cl->mic_funcs[impl] != NULL)
					test_implementation = 1;
				break;
			case STARPU_SCC_WORKER:
				if (task->cl->cpu_funcs_name[impl] != NULL || task->cl->scc_funcs[impl] != NULL)
					test_implementation = 1;
				break;
			default:
				STARPU_ABORT();
			}

			if (!test_implementation)
				continue;

			if (task->cl->can_execute)
				return task->cl->can_execute(i, task, impl);

			if(test_implementation)
				return 1;
		}
	}

	return 0;
}

/* in case a task is submitted, we may check whether there exists a worker
   that may execute the task or not */
uint32_t _starpu_worker_exists(struct starpu_task *task)
{
	_starpu_codelet_check_deprecated_fields(task->cl);

	/* if the task belongs to the init context we can
	   check out all the worker mask of the machine
	   if not we should iterate on the workers of the ctx
	   and verify if it exists a worker able to exec the task */
	if(task->sched_ctx == 0)
	{
		if (!(task->cl->where & config.worker_mask))
			return 0;

		if (!task->cl->can_execute)
			return 1;
	}

#if defined(STARPU_USE_CPU) || defined(STARPU_SIMGRID)
	if ((task->cl->where & STARPU_CPU) &&
	    _starpu_worker_exists_and_can_execute(task, STARPU_CPU_WORKER))
		return 1;
#endif
#if defined(STARPU_USE_CUDA) || defined(STARPU_SIMGRID)
	if ((task->cl->where & STARPU_CUDA) &&
	    _starpu_worker_exists_and_can_execute(task, STARPU_CUDA_WORKER))
		return 1;
#endif
#if defined(STARPU_USE_OPENCL) || defined(STARPU_SIMGRID)
	if ((task->cl->where & STARPU_OPENCL) &&
	    _starpu_worker_exists_and_can_execute(task, STARPU_OPENCL_WORKER))
		return 1;
#endif
#ifdef STARPU_USE_MIC
	if ((task->cl->where & STARPU_MIC) &&
	    _starpu_worker_exists_and_can_execute(task, STARPU_MIC_WORKER))
		return 1;
#endif
#ifdef STARPU_USE_SCC
	if ((task->cl->where & STARPU_SCC) &&
	    _starpu_worker_exists_and_can_execute(task, STARPU_SCC_WORKER))
		return 1;
#endif

	return 0;
}

uint32_t _starpu_can_submit_cuda_task(void)
{
	return (STARPU_CUDA & config.worker_mask);
}

uint32_t _starpu_can_submit_cpu_task(void)
{
	return (STARPU_CPU & config.worker_mask);
}

uint32_t _starpu_can_submit_opencl_task(void)
{
	return (STARPU_OPENCL & config.worker_mask);
}

uint32_t _starpu_can_submit_scc_task(void)
{
	return (STARPU_SCC & config.worker_mask);
}

static inline int _starpu_can_use_nth_implementation(enum starpu_worker_archtype arch, struct starpu_codelet *cl, unsigned nimpl)
{
	switch(arch)
	{
	case STARPU_ANY_WORKER:
	{
		int cpu_func_enabled=1, cuda_func_enabled=1, opencl_func_enabled=1;
		/* TODO: MIC/SCC */

#if defined(STARPU_USE_CPU) || defined(STARPU_SIMGRID)
		starpu_cpu_func_t cpu_func = _starpu_task_get_cpu_nth_implementation(cl, nimpl);
		cpu_func_enabled = cpu_func != NULL && starpu_cpu_worker_get_count();
#endif
#if defined(STARPU_USE_CUDA) || defined(STARPU_SIMGRID)
		starpu_cuda_func_t cuda_func = _starpu_task_get_cuda_nth_implementation(cl, nimpl);
		cuda_func_enabled = cuda_func != NULL && starpu_cuda_worker_get_count();
#endif
#if defined(STARPU_USE_OPENCL) || defined(STARPU_SIMGRID)
		starpu_opencl_func_t opencl_func = _starpu_task_get_opencl_nth_implementation(cl, nimpl);
		opencl_func_enabled = opencl_func != NULL && starpu_opencl_worker_get_count();
#endif

		return (cpu_func_enabled && cuda_func_enabled && opencl_func_enabled);
	}
	case STARPU_CPU_WORKER:
	{
		starpu_cpu_func_t func = _starpu_task_get_cpu_nth_implementation(cl, nimpl);
		return func != NULL;
	}
	case STARPU_CUDA_WORKER:
	{
		starpu_cuda_func_t func = _starpu_task_get_cuda_nth_implementation(cl, nimpl);
		return func != NULL;
	}
	case STARPU_OPENCL_WORKER:
	{
		starpu_opencl_func_t func = _starpu_task_get_opencl_nth_implementation(cl, nimpl);
		return func != NULL;
	}
	case STARPU_MIC_WORKER:
	{
		starpu_mic_func_t func = _starpu_task_get_mic_nth_implementation(cl, nimpl);
		char *func_name = _starpu_task_get_cpu_name_nth_implementation(cl, nimpl);

		return func != NULL || func_name != NULL;
	}
	case STARPU_SCC_WORKER:
	{
		starpu_scc_func_t func = _starpu_task_get_scc_nth_implementation(cl, nimpl);
		char *func_name = _starpu_task_get_cpu_name_nth_implementation(cl, nimpl);

		return func != NULL || func_name != NULL;
	}
	default:
		STARPU_ASSERT_MSG(0, "Unknown arch type %d", arch);
	}
	return 0;
}

int starpu_worker_can_execute_task(unsigned workerid, struct starpu_task *task, unsigned nimpl)
{
	struct _starpu_sched_ctx *sched_ctx = _starpu_get_sched_ctx_struct(task->sched_ctx);

	/* if the task can't be parallel don't submit it to a ctx */
	unsigned child_sched_ctx = starpu_sched_ctx_worker_is_master_for_child_ctx(workerid, sched_ctx->id);
        if(child_sched_ctx != STARPU_NMAX_SCHED_CTXS)
		if(!task->possibly_parallel) return 0;

	/* if the worker is blocked in a parallel ctx don't submit tasks on it */
	if(sched_ctx->parallel_sect[workerid] ) return 0;

	/* TODO: check that the task operand sizes will fit on that device */
	return (task->cl->where & config.workers[workerid].worker_mask) &&
		_starpu_can_use_nth_implementation(config.workers[workerid].arch, task->cl, nimpl) &&
		(!task->cl->can_execute || task->cl->can_execute(workerid, task, nimpl));
}

int starpu_worker_can_execute_task_impl(unsigned workerid, struct starpu_task *task, unsigned *impl_mask)
{
	struct _starpu_sched_ctx *sched_ctx = _starpu_get_sched_ctx_struct(task->sched_ctx);

	/* if the worker is blocked in a parallel ctx don't submit tasks on it */
	if(sched_ctx->parallel_sect[workerid]) return 0;

	unsigned mask;
	int i;
	enum starpu_worker_archtype arch;
	struct starpu_codelet *cl;
	/* TODO: check that the task operand sizes will fit on that device */
	cl = task->cl;
	if (!(cl->where & config.workers[workerid].worker_mask)) return 0;

	mask = 0;
	arch = config.workers[workerid].arch;
	if (!task->cl->can_execute)
	{
		for (i = 0; i < STARPU_MAXIMPLEMENTATIONS; i++)
			if (_starpu_can_use_nth_implementation(arch, cl, i))
			{
				mask |= 1U << i;
				if (!impl_mask)
					break;
			}
	}
	else
	{
		for (i = 0; i < STARPU_MAXIMPLEMENTATIONS; i++)
			if (_starpu_can_use_nth_implementation(arch, cl, i)
			 && (!task->cl->can_execute || task->cl->can_execute(workerid, task, i)))
			{
				mask |= 1U << i;
				if (!impl_mask)
					break;
			}
	}
	if (impl_mask)
		*impl_mask = mask;
	return mask != 0;
}

int starpu_worker_can_execute_task_first_impl(unsigned workerid, struct starpu_task *task, unsigned *nimpl)
{
	struct _starpu_sched_ctx *sched_ctx = _starpu_get_sched_ctx_struct(task->sched_ctx);
	int i;
	enum starpu_worker_archtype arch;
	struct starpu_codelet *cl;
	if(sched_ctx->parallel_sect[workerid]) return 0;
	/* TODO: check that the task operand sizes will fit on that device */
	cl = task->cl;
	if (!(cl->where & config.workers[workerid].worker_mask)) return 0;

	arch = config.workers[workerid].arch;
	if (!task->cl->can_execute)
	{
		for (i = 0; i < STARPU_MAXIMPLEMENTATIONS; i++)
			if (_starpu_can_use_nth_implementation(arch, cl, i))
			{
				if (nimpl)
					*nimpl = i;
				return 1;
			}
	}
	else
	{
		for (i = 0; i < STARPU_MAXIMPLEMENTATIONS; i++)
			if (_starpu_can_use_nth_implementation(arch, cl, i)
			 && (!task->cl->can_execute || task->cl->can_execute(workerid, task, i)))
			{
				if (nimpl)
					*nimpl = i;
				return 1;
			}
	}
	return 0;
}



int starpu_combined_worker_can_execute_task(unsigned workerid, struct starpu_task *task, unsigned nimpl)
{
	/* TODO: check that the task operand sizes will fit on that device */

	struct starpu_codelet *cl = task->cl;
	unsigned nworkers = config.topology.nworkers;

	/* Is this a parallel worker ? */
	if (workerid < nworkers)
	{
		return !!((task->cl->where & config.workers[workerid].worker_mask) &&
				_starpu_can_use_nth_implementation(config.workers[workerid].arch, task->cl, nimpl) &&
				(!task->cl->can_execute || task->cl->can_execute(workerid, task, nimpl)));
	}
	else
	{
		if ((cl->type == STARPU_SPMD)
#ifdef STARPU_HAVE_HWLOC
				|| (cl->type == STARPU_FORKJOIN)
#else
#ifdef __GLIBC__
				|| (cl->type == STARPU_FORKJOIN)
#endif
#endif

				)
		{
			/* TODO we should add other types of constraints */

			/* Is the worker larger than requested ? */
			int worker_size = (int)config.combined_workers[workerid - nworkers].worker_size;
			int worker0 = config.combined_workers[workerid - nworkers].combined_workerid[0];
			return !!((worker_size <= task->cl->max_parallelism) &&
				_starpu_can_use_nth_implementation(config.workers[worker0].arch, task->cl, nimpl) &&
				(!task->cl->can_execute || task->cl->can_execute(workerid, task, nimpl)));
		}
		else
		{
			/* We have a sequential task but a parallel worker */
			return 0;
		}
	}
}

/*
 * Runtime initialization methods
 */

#if defined(STARPU_USE_CUDA) || defined(STARPU_SIMGRID)
static struct _starpu_worker_set cuda_worker_set[STARPU_MAXCUDADEVS];
#endif
#ifdef STARPU_USE_MIC
static struct _starpu_worker_set mic_worker_set[STARPU_MAXMICDEVS];
#endif

static void _starpu_init_worker_queue(struct _starpu_worker *workerarg)
{
	starpu_pthread_cond_t *cond = &workerarg->sched_cond;
	starpu_pthread_mutex_t *mutex = &workerarg->sched_mutex;

	unsigned memory_node = workerarg->memory_node;

	_starpu_memory_node_register_condition(cond, mutex, memory_node);
}

/*
 * Returns 0 if the given driver is one of the drivers that must be launched by
 * the application itself, and not by StarPU, 1 otherwise.
 */
static unsigned _starpu_may_launch_driver(struct starpu_conf *conf,
					  struct starpu_driver *d)
{
	if (conf->n_not_launched_drivers == 0 ||
	    conf->not_launched_drivers == NULL)
		return 1;

	/* Is <d> in conf->not_launched_drivers ? */
	unsigned i;
	for (i = 0; i < conf->n_not_launched_drivers; i++)
	{
		if (d->type != conf->not_launched_drivers[i].type)
			continue;

		switch (d->type)
		{
		case STARPU_CPU_WORKER:
			if (d->id.cpu_id == conf->not_launched_drivers[i].id.cpu_id)
				return 0;
		case STARPU_CUDA_WORKER:
			if (d->id.cuda_id == conf->not_launched_drivers[i].id.cuda_id)
				return 0;
			break;
#ifdef STARPU_USE_OPENCL
		case STARPU_OPENCL_WORKER:
			if (d->id.opencl_id == conf->not_launched_drivers[i].id.opencl_id)
				return 0;
			break;
#endif
		default:
			STARPU_ABORT();
		}
	}

	return 1;
}

#ifdef STARPU_PERF_DEBUG
struct itimerval prof_itimer;
#endif

static void _starpu_worker_init(struct _starpu_worker *workerarg, struct _starpu_machine_config *pconfig)
{
	workerarg->config = pconfig;
	STARPU_PTHREAD_MUTEX_INIT(&workerarg->mutex, NULL);
	/* arch initialized by topology.c */
	/* worker_mask initialized by topology.c */
	/* perf_arch initialized by topology.c */
	/* worker_thread initialized by _starpu_launch_drivers */
	/* devid initialized by topology.c */
	/* subworkerid initialized by topology.c */
	/* bindid initialized by topology.c */
	/* workerid initialized by topology.c */
	workerarg->combined_workerid = workerarg->workerid;
	workerarg->current_rank = 0;
	workerarg->worker_size = 1;
	STARPU_PTHREAD_COND_INIT(&workerarg->started_cond, NULL);
	STARPU_PTHREAD_COND_INIT(&workerarg->ready_cond, NULL);
	/* memory_node initialized by topology.c */
	STARPU_PTHREAD_COND_INIT(&workerarg->sched_cond, NULL);
	STARPU_PTHREAD_MUTEX_INIT(&workerarg->sched_mutex, NULL);
	starpu_task_list_init(&workerarg->local_tasks);
	workerarg->local_ordered_tasks = NULL;
	workerarg->local_ordered_tasks_size = 0;
	workerarg->current_ordered_task = 0;
	workerarg->current_ordered_task_order = 1;
	workerarg->current_task = NULL;
	workerarg->first_task = 0;
	workerarg->ntasks = 0;
	workerarg->pipeline_length = 0;
	workerarg->pipeline_stuck = 0;
	workerarg->set = NULL;
	workerarg->worker_is_running = 0;
	workerarg->worker_is_initialized = 0;
	workerarg->status = STATUS_INITIALIZING;
	/* name initialized by driver */
	/* short_name initialized by driver */
	workerarg->run_by_starpu = 1;

	workerarg->sched_ctx_list = NULL;
	workerarg->tmp_sched_ctx = -1;
	workerarg->nsched_ctxs = 0;
	_starpu_barrier_counter_init(&workerarg->tasks_barrier, 0);

	workerarg->has_prev_init = 0;

	int ctx;
	for(ctx = 0; ctx < STARPU_NMAX_SCHED_CTXS; ctx++)
		workerarg->removed_from_ctx[ctx] = 0;

	workerarg->spinning_backoff = 1;


	for(ctx = 0; ctx < STARPU_NMAX_SCHED_CTXS; ctx++)
	{
		workerarg->shares_tasks_lists[ctx] = 0;
		workerarg->poped_in_ctx[ctx] = 0;
	}
	workerarg->reverse_phase[0] = 0;
	workerarg->reverse_phase[1] = 0;
	workerarg->pop_ctx_priority = 1;
	workerarg->sched_mutex_locked = 0;
	workerarg->blocked = 0;
	workerarg->is_slave_somewhere = 0;

	/* cpu_set/hwloc_cpu_set initialized in topology.c */
}

#ifdef STARPU_USE_FXT
void _starpu_worker_start(struct _starpu_worker *worker, unsigned fut_key, unsigned sync)
{
	unsigned devid = worker->devid;
	unsigned memnode = worker->memory_node;
	_STARPU_TRACE_WORKER_INIT_START(fut_key, worker->workerid, devid, memnode, worker->bindid, sync);
}
#endif

void _starpu_driver_start(struct _starpu_worker *worker, unsigned fut_key, unsigned sync STARPU_ATTRIBUTE_UNUSED)
{
	(void) fut_key;
	int devid = worker->devid;
	(void) devid;

#if defined(STARPU_PERF_DEBUG) && !defined(STARPU_SIMGRID)
	setitimer(ITIMER_PROF, &prof_itimer, NULL);
#endif

#ifdef STARPU_USE_FXT
	_starpu_fxt_register_thread(worker->bindid);
	_starpu_worker_start(worker, fut_key, sync);
#endif

	_starpu_bind_thread_on_cpu(worker->config, worker->bindid);

        _STARPU_DEBUG("worker %p %d for dev %d is ready on logical cpu %d\n", worker, worker->workerid, devid, worker->bindid);
#ifdef STARPU_HAVE_HWLOC
	_STARPU_DEBUG("worker %p %d cpuset start at %d\n", worker, worker->workerid, hwloc_bitmap_first(worker->hwloc_cpu_set));
#endif

	_starpu_memory_node_set_local_key(&worker->memory_node);

	_starpu_set_local_worker_key(worker);

	STARPU_PTHREAD_MUTEX_LOCK(&worker->mutex);
	worker->worker_is_running = 1;
	STARPU_PTHREAD_COND_SIGNAL(&worker->started_cond);
	STARPU_PTHREAD_MUTEX_UNLOCK(&worker->mutex);
}

static void _starpu_launch_drivers(struct _starpu_machine_config *pconfig)
{
	pconfig->running = 1;
	pconfig->pause_depth = 0;
	pconfig->submitting = 1;
	STARPU_HG_DISABLE_CHECKING(pconfig->watchdog_ok);

	unsigned nworkers = pconfig->topology.nworkers;

	/* Launch workers asynchronously */
	unsigned worker;
#if defined(STARPU_USE_CUDA) || defined(STARPU_SIMGRID) || defined(STARPU_USE_MIC)
	unsigned i;
#endif

#if defined(STARPU_PERF_DEBUG) && !defined(STARPU_SIMGRID)
	/* Get itimer of the main thread, to set it for the worker threads */
	getitimer(ITIMER_PROF, &prof_itimer);
#endif

#ifdef HAVE_AYUDAME_H
	if (AYU_event) AYU_event(AYU_INIT, 0, NULL);
#endif

#if defined(STARPU_USE_CUDA) || defined(STARPU_SIMGRID)
	for (i = 0; i < sizeof(cuda_worker_set)/sizeof(cuda_worker_set[0]); i++)
		cuda_worker_set[i].workers = NULL;
#endif
#ifdef STARPU_USE_MIC
	for (i = 0; i < sizeof(mic_worker_set)/sizeof(mic_worker_set[0]); i++)
		mic_worker_set[i].workers = NULL;
#endif

	for (worker = 0; worker < nworkers; worker++)
	{
		struct _starpu_worker *workerarg = &pconfig->workers[worker];
#if defined(STARPU_USE_MIC) || defined(STARPU_USE_CUDA) || defined(STARPU_SIMGRID)
		unsigned devid = workerarg->devid;
#endif
#if defined(STARPU_USE_CUDA) || defined(STARPU_SIMGRID)
		struct _starpu_worker_set *worker_set;
#endif

		_STARPU_DEBUG("initialising worker %u/%u\n", worker, nworkers);

		_starpu_init_worker_queue(workerarg);

		struct starpu_driver driver;
		driver.type = workerarg->arch;
		switch (workerarg->arch)
		{
#if defined(STARPU_USE_CPU) || defined(STARPU_SIMGRID)
			case STARPU_CPU_WORKER:
				driver.id.cpu_id = workerarg->devid;
				if (_starpu_may_launch_driver(pconfig->conf, &driver))
				{
					STARPU_PTHREAD_CREATE_ON(
						workerarg->name,
						&workerarg->worker_thread,
						NULL,
						_starpu_cpu_worker,
						workerarg,
						_starpu_simgrid_get_host_by_worker(workerarg));
#ifdef STARPU_USE_FXT
					/* In tracing mode, make sure the
					 * thread is really started before
					 * starting another one, to make sure
					 * they appear in order in the trace.
					 */
					STARPU_PTHREAD_MUTEX_LOCK(&workerarg->mutex);
					while (!workerarg->worker_is_running)
						STARPU_PTHREAD_COND_WAIT(&workerarg->started_cond, &workerarg->mutex);
					STARPU_PTHREAD_MUTEX_UNLOCK(&workerarg->mutex);
#endif
				}
				else
				{
					workerarg->run_by_starpu = 0;
				}
				break;
#endif
#if defined(STARPU_USE_CUDA) || defined(STARPU_SIMGRID)
			case STARPU_CUDA_WORKER:
				driver.id.cuda_id = workerarg->devid;
				worker_set = &cuda_worker_set[devid];
				workerarg->set = worker_set;

				/* We spawn only one thread per CUDA driver,
				 * which will control all CUDA workers of this
				 * driver. (by using a worker set). */
				if (worker_set->workers)
					break;

				worker_set->nworkers = starpu_get_env_number_default("STARPU_NWORKER_PER_CUDA", 1);

#ifndef STARPU_NON_BLOCKING_DRIVERS
				if (worker_set->nworkers > 1)
				{
					_STARPU_DISP("Warning: reducing STARPU_NWORKER_PER_CUDA to 1 because blocking drivers are enabled\n");
					worker_set->nworkers = 1;
				}
#endif

				worker_set->workers = workerarg;
				worker_set->set_is_initialized = 0;

				if (!_starpu_may_launch_driver(pconfig->conf, &driver))
				{
					workerarg->run_by_starpu = 0;
					break;
				}

				STARPU_PTHREAD_CREATE_ON(
					workerarg->name,
					&worker_set->worker_thread,
					NULL,
					_starpu_cuda_worker,
					worker_set,
					_starpu_simgrid_get_host_by_worker(workerarg));
#ifdef STARPU_USE_FXT
				STARPU_PTHREAD_MUTEX_LOCK(&workerarg->mutex);
				while (!workerarg->worker_is_running)
					STARPU_PTHREAD_COND_WAIT(&workerarg->started_cond, &workerarg->mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&workerarg->mutex);
#endif
				STARPU_PTHREAD_MUTEX_LOCK(&worker_set->mutex);
				while (!worker_set->set_is_initialized)
					STARPU_PTHREAD_COND_WAIT(&worker_set->ready_cond,
								 &worker_set->mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&worker_set->mutex);
				worker_set->started = 1;

				break;
#endif
#if defined(STARPU_USE_OPENCL) || defined(STARPU_SIMGRID)
			case STARPU_OPENCL_WORKER:
#ifndef STARPU_SIMGRID
				starpu_opencl_get_device(workerarg->devid, &driver.id.opencl_id);
				if (!_starpu_may_launch_driver(pconfig->conf, &driver))
				{
					workerarg->run_by_starpu = 0;
					break;
				}
#endif
				STARPU_PTHREAD_CREATE_ON(
					workerarg->name,
					&workerarg->worker_thread,
					NULL,
					_starpu_opencl_worker,
					workerarg,
					_starpu_simgrid_get_host_by_worker(workerarg));
#ifdef STARPU_USE_FXT
				STARPU_PTHREAD_MUTEX_LOCK(&workerarg->mutex);
				while (!workerarg->worker_is_running)
					STARPU_PTHREAD_COND_WAIT(&workerarg->started_cond, &workerarg->mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&workerarg->mutex);
#endif
				break;
#endif
#ifdef STARPU_USE_MIC
			case STARPU_MIC_WORKER:
				workerarg->set = &mic_worker_set[devid];

				/* We spawn only one thread
				 * per MIC device, which will control all MIC
				 * workers of this device. (by using a worker set). */
				if (mic_worker_set[devid].workers)
					break;

				mic_worker_set[devid].nworkers = pconfig->topology.nmiccores[devid];

				/* We assume all MIC workers of a given MIC
				 * device are contiguous so that we can
				 * address them with the first one only. */
				mic_worker_set[devid].workers = workerarg;
				mic_worker_set[devid].set_is_initialized = 0;

				STARPU_PTHREAD_CREATE_ON(
						workerarg->name,
						&mic_worker_set[devid].worker_thread,
						NULL,
						_starpu_mic_src_worker,
						&mic_worker_set[devid],
						_starpu_simgrid_get_host_by_worker(workerarg));

#ifdef STARPU_USE_FXT
				STARPU_PTHREAD_MUTEX_LOCK(&workerarg->mutex);
				while (!workerarg->worker_is_running)
					STARPU_PTHREAD_COND_WAIT(&workerarg->started_cond, &workerarg->mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&workerarg->mutex);
#endif

				STARPU_PTHREAD_MUTEX_LOCK(&mic_worker_set[devid].mutex);
				while (!mic_worker_set[devid].set_is_initialized)
					STARPU_PTHREAD_COND_WAIT(&mic_worker_set[devid].ready_cond,
								  &mic_worker_set[devid].mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&mic_worker_set[devid].mutex);

				mic_worker_set[devid].started = 1;

				break;
#endif /* STARPU_USE_MIC */
#ifdef STARPU_USE_SCC
			case STARPU_SCC_WORKER:
				workerarg->worker_is_initialized = 0;
				STARPU_PTHREAD_CREATE_ON(
						workerarg->name,
						&workerarg->worker_thread,
						NULL,
						_starpu_scc_src_worker,
						workerarg,
						_starpu_simgrid_get_host_by_worker(workerarg));

#ifdef STARPU_USE_FXT
				STARPU_PTHREAD_MUTEX_LOCK(&workerarg->mutex);
				while (!workerarg->worker_is_running)
					STARPU_PTHREAD_COND_WAIT(&workerarg->started_cond, &workerarg->mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&workerarg->mutex);
#endif
				break;
#endif

			default:
				STARPU_ABORT();
		}
	}

	for (worker = 0; worker < nworkers; worker++)
	{
		struct _starpu_worker *workerarg = &pconfig->workers[worker];
		struct starpu_driver driver;
		driver.type = workerarg->arch;

		switch (workerarg->arch)
		{
			case STARPU_CPU_WORKER:
				driver.id.cpu_id = workerarg->devid;
				if (!_starpu_may_launch_driver(pconfig->conf, &driver))
					break;
				_STARPU_DEBUG("waiting for worker %u initialization\n", worker);
				STARPU_PTHREAD_MUTEX_LOCK(&workerarg->mutex);
				while (!workerarg->worker_is_initialized)
					STARPU_PTHREAD_COND_WAIT(&workerarg->ready_cond, &workerarg->mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&workerarg->mutex);
				break;
			case STARPU_CUDA_WORKER:
				/* Already waited above */
				break;
#if defined(STARPU_USE_OPENCL) || defined(STARPU_SIMGRID)
			case STARPU_OPENCL_WORKER:
#ifndef STARPU_SIMGRID
				starpu_opencl_get_device(workerarg->devid, &driver.id.opencl_id);
				if (!_starpu_may_launch_driver(pconfig->conf, &driver))
					break;
#endif
				_STARPU_DEBUG("waiting for worker %u initialization\n", worker);
				STARPU_PTHREAD_MUTEX_LOCK(&workerarg->mutex);
				while (!workerarg->worker_is_initialized)
					STARPU_PTHREAD_COND_WAIT(&workerarg->ready_cond, &workerarg->mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&workerarg->mutex);
				break;
#endif
			case STARPU_MIC_WORKER:
				/* Already waited above */
				break;
			case STARPU_SCC_WORKER:
				/* TODO: implement may_launch? */
				_STARPU_DEBUG("waiting for worker %u initialization\n", worker);
				STARPU_PTHREAD_MUTEX_LOCK(&workerarg->mutex);
				while (!workerarg->worker_is_initialized)
					STARPU_PTHREAD_COND_WAIT(&workerarg->ready_cond, &workerarg->mutex);
				STARPU_PTHREAD_MUTEX_UNLOCK(&workerarg->mutex);
				break;
			default:
				STARPU_ABORT();
		}
	}

	_STARPU_DEBUG("finished launching drivers\n");
}

void _starpu_set_local_worker_key(struct _starpu_worker *worker)
{
	STARPU_PTHREAD_SETSPECIFIC(worker_key, worker);
}

struct _starpu_worker *_starpu_get_local_worker_key(void)
{
	return (struct _starpu_worker *) STARPU_PTHREAD_GETSPECIFIC(worker_key);
}

void _starpu_set_local_worker_set_key(struct _starpu_worker_set *worker)
{
	STARPU_PTHREAD_SETSPECIFIC(worker_set_key, worker);
}

struct _starpu_worker_set *_starpu_get_local_worker_set_key(void)
{
	return (struct _starpu_worker_set *) STARPU_PTHREAD_GETSPECIFIC(worker_set_key);
}

/* Initialize the starpu_conf with default values */
int starpu_conf_init(struct starpu_conf *conf)
{
	if (!conf)
		return -EINVAL;

	memset(conf, 0, sizeof(*conf));
	conf->magic = 42;
	conf->sched_policy_name = getenv("STARPU_SCHED");
	conf->sched_policy = NULL;
	conf->global_sched_ctx_min_priority = starpu_get_env_number("STARPU_MIN_PRIO");
	conf->global_sched_ctx_max_priority = starpu_get_env_number("STARPU_MAX_PRIO");

	/* Note that starpu_get_env_number returns -1 in case the variable is
	 * not defined */
	/* Backward compatibility: check the value of STARPU_NCPUS if
	 * STARPU_NCPU is not set. */
	conf->ncpus = starpu_get_env_number("STARPU_NCPU");
	if (conf->ncpus == -1)
		conf->ncpus = starpu_get_env_number("STARPU_NCPUS");
	conf->ncuda = starpu_get_env_number("STARPU_NCUDA");
	conf->nopencl = starpu_get_env_number("STARPU_NOPENCL");
	conf->nmic = starpu_get_env_number("STARPU_NMIC");
	conf->nscc = starpu_get_env_number("STARPU_NSCC");
	conf->calibrate = starpu_get_env_number("STARPU_CALIBRATE");
	conf->bus_calibrate = starpu_get_env_number("STARPU_BUS_CALIBRATE");
	conf->mic_sink_program_path = getenv("STARPU_MIC_PROGRAM_PATH");

	if (conf->calibrate == -1)
	     conf->calibrate = 0;

	if (conf->bus_calibrate == -1)
	     conf->bus_calibrate = 0;

	conf->use_explicit_workers_bindid = 0; /* TODO */
	conf->use_explicit_workers_cuda_gpuid = 0; /* TODO */
	conf->use_explicit_workers_opencl_gpuid = 0; /* TODO */
	conf->use_explicit_workers_mic_deviceid = 0; /* TODO */
	conf->use_explicit_workers_scc_deviceid = 0; /* TODO */

	conf->single_combined_worker = starpu_get_env_number("STARPU_SINGLE_COMBINED_WORKER");
	if (conf->single_combined_worker == -1)
	     conf->single_combined_worker = 0;

#if defined(STARPU_DISABLE_ASYNCHRONOUS_COPY)
	conf->disable_asynchronous_copy = 1;
#else
	conf->disable_asynchronous_copy = starpu_get_env_number("STARPU_DISABLE_ASYNCHRONOUS_COPY");
	if (conf->disable_asynchronous_copy == -1)
		conf->disable_asynchronous_copy = 0;
#endif

#if defined(STARPU_DISABLE_ASYNCHRONOUS_CUDA_COPY)
	conf->disable_asynchronous_cuda_copy = 1;
#else
	conf->disable_asynchronous_cuda_copy = starpu_get_env_number("STARPU_DISABLE_ASYNCHRONOUS_CUDA_COPY");
	if (conf->disable_asynchronous_cuda_copy == -1)
		conf->disable_asynchronous_cuda_copy = 0;
#endif

#if defined(STARPU_DISABLE_ASYNCHRONOUS_OPENCL_COPY)
	conf->disable_asynchronous_opencl_copy = 1;
#else
	conf->disable_asynchronous_opencl_copy = starpu_get_env_number("STARPU_DISABLE_ASYNCHRONOUS_OPENCL_COPY");
	if (conf->disable_asynchronous_opencl_copy == -1)
		conf->disable_asynchronous_opencl_copy = 0;
#endif

#if defined(STARPU_DISABLE_ASYNCHRONOUS_MIC_COPY)
	conf->disable_asynchronous_mic_copy = 1;
#else
	conf->disable_asynchronous_mic_copy = starpu_get_env_number("STARPU_DISABLE_ASYNCHRONOUS_MIC_COPY");
	if (conf->disable_asynchronous_mic_copy == -1)
		conf->disable_asynchronous_mic_copy = 0;
#endif

	/* 64MiB by default */
	conf->trace_buffer_size = starpu_get_env_number_default("STARPU_TRACE_BUFFER_SIZE", 64) << 20;
	return 0;
}

static void _starpu_conf_set_value_against_environment(char *name, int *value)
{
	int number;
	number = starpu_get_env_number(name);
	if (number != -1)
	{
		*value = number;
	}
}

void _starpu_conf_check_environment(struct starpu_conf *conf)
{
	char *sched = getenv("STARPU_SCHED");
	if (sched)
	{
		conf->sched_policy_name = sched;
	}

	_starpu_conf_set_value_against_environment("STARPU_NCPUS", &conf->ncpus);
	_starpu_conf_set_value_against_environment("STARPU_NCPU", &conf->ncpus);
	_starpu_conf_set_value_against_environment("STARPU_NCUDA", &conf->ncuda);
	_starpu_conf_set_value_against_environment("STARPU_NOPENCL", &conf->nopencl);
	_starpu_conf_set_value_against_environment("STARPU_CALIBRATE", &conf->calibrate);
	_starpu_conf_set_value_against_environment("STARPU_BUS_CALIBRATE", &conf->bus_calibrate);
#ifdef STARPU_SIMGRID
	if (conf->calibrate == 2)
	{
		_STARPU_DISP("Warning: History will be cleared due to calibrate or STARPU_CALIBRATE being set to 2. This will prevent simgrid from having task simulation times!");
	}
	if (conf->bus_calibrate)
	{
		_STARPU_DISP("Warning: Bus calibration will be cleared due to bus_calibrate or STARPU_BUS_CALIBRATE being set. This will prevent simgrid from having data transfer simulation times!");
	}
#endif
	_starpu_conf_set_value_against_environment("STARPU_SINGLE_COMBINED_WORKER", &conf->single_combined_worker);
	_starpu_conf_set_value_against_environment("STARPU_DISABLE_ASYNCHRONOUS_COPY", &conf->disable_asynchronous_copy);
	_starpu_conf_set_value_against_environment("STARPU_DISABLE_ASYNCHRONOUS_CUDA_COPY", &conf->disable_asynchronous_cuda_copy);
	_starpu_conf_set_value_against_environment("STARPU_DISABLE_ASYNCHRONOUS_OPENCL_COPY", &conf->disable_asynchronous_opencl_copy);
	_starpu_conf_set_value_against_environment("STARPU_DISABLE_ASYNCHRONOUS_MIC_COPY", &conf->disable_asynchronous_mic_copy);
}

struct starpu_tree* starpu_workers_get_tree(void)
{
	return config.topology.tree;
}

#ifdef STARPU_HAVE_HWLOC
static void _fill_tree(struct starpu_tree *tree, hwloc_obj_t curr_obj, unsigned depth, hwloc_topology_t topology)
{
	unsigned i;
	for(i = 0; i < curr_obj->arity; i++)
	{
		starpu_tree_insert(tree->nodes[i], curr_obj->children[i]->logical_index, depth, curr_obj->children[i]->type == HWLOC_OBJ_PU, curr_obj->children[i]->arity, tree);
/* 		char string[128]; */
/* 		hwloc_obj_snprintf(string, sizeof(string), topology, curr_obj->children[i], "#", 0); */
/* 		printf("%*s%s %d is_pu %d \n", 0, "", string, curr_obj->children[i]->logical_index, curr_obj->children[i]->type == HWLOC_OBJ_PU); */
		_fill_tree(tree->nodes[i], curr_obj->children[i], depth+1, topology);
	}
}
#endif

static void _starpu_build_tree(void)
{
#ifdef STARPU_HAVE_HWLOC
	struct starpu_tree* tree = (struct starpu_tree*)malloc(sizeof(struct starpu_tree));
	config.topology.tree = tree;

	hwloc_obj_t root = hwloc_get_root_obj(config.topology.hwtopology);

/* 	char string[128]; */
/* 	hwloc_obj_snprintf(string, sizeof(string), topology, root, "#", 0); */
/* 	printf("%*s%s %d is_pu = %d \n", 0, "", string, root->logical_index, root->type == HWLOC_OBJ_PU); */

	/* level, is_pu, is in the tree (it will be true only after add*/
	starpu_tree_insert(tree, root->logical_index, 0,root->type == HWLOC_OBJ_PU, root->arity, NULL);
	_fill_tree(tree, root, 1, config.topology.hwtopology);
#endif
}

int starpu_init(struct starpu_conf *user_conf)
{
	return starpu_initialize(user_conf, NULL, NULL);
}

int starpu_initialize(struct starpu_conf *user_conf, int *argc, char ***argv)
{
	int is_a_sink = 0; /* Always defined. If the MP infrastructure is not
			    * used, we cannot be a sink. */
	unsigned worker;
#ifdef STARPU_USE_MP
	_starpu_set_argc_argv(argc, argv);

#	ifdef STARPU_USE_SCC
	/* In SCC case we look at the rank to know if we are a sink */
	if (_starpu_scc_common_mp_init() && !_starpu_scc_common_is_src_node())
		setenv("STARPU_SINK", "STARPU_SCC", 1);
#	endif

	/* If StarPU was configured to use MP sinks, we have to control the
	 * kind on node we are running on : host or sink ? */
	if (getenv("STARPU_SINK"))
		is_a_sink = 1;
#else
	(void)argc;
	(void)argv;

#endif /* STARPU_USE_MP */

	int ret;

#ifdef STARPU_OPENMP
	_starpu_omp_dummy_init();
#endif
#ifdef STARPU_SIMGRID
	_starpu_simgrid_init();
	/* Warn when the lots of stacks malloc()-ated by simgrid for transfer
	 * processes will take a long time to get initialized */
	if (getenv("MALLOC_PERTURB_"))
		_STARPU_DISP("Warning: MALLOC_PERTURB_ is set, this makes simgrid runs very slow\n");
#else
#ifdef __GNUC__
#ifndef __OPTIMIZE__
	_STARPU_DISP("Warning: StarPU was configured with --enable-debug (-O0), and is thus not optimized\n");
#endif
#endif
#ifdef STARPU_SPINLOCK_CHECK
	_STARPU_DISP("Warning: StarPU was configured with --enable-spinlock-check, which slows down a bit\n");
#endif
#if 0
#ifndef STARPU_NO_ASSERT
	_STARPU_DISP("Warning: StarPU was configured without --enable-fast\n");
#endif
#endif
#ifdef STARPU_MEMORY_STATS
	_STARPU_DISP("Warning: StarPU was configured with --enable-memory-stats, which slows down a bit\n");
#endif
#ifdef STARPU_VERBOSE
	_STARPU_DISP("Warning: StarPU was configured with --enable-verbose, which slows down a bit\n");
#endif
#ifdef STARPU_USE_FXT
	_STARPU_DISP("Warning: StarPU was configured with --with-fxt, which slows down a bit\n");
#endif
#ifdef STARPU_PERF_DEBUG
	_STARPU_DISP("Warning: StarPU was configured with --enable-perf-debug, which slows down a bit\n");
#endif
#ifdef STARPU_MODEL_DEBUG
	_STARPU_DISP("Warning: StarPU was configured with --enable-model-debug, which slows down a bit\n");
#endif
#ifdef STARPU_ENABLE_STATS
	_STARPU_DISP("Warning: StarPU was configured with --enable-stats, which slows down a bit\n");
#endif
#endif

	STARPU_PTHREAD_MUTEX_LOCK(&init_mutex);
	while (initialized == CHANGING)
		/* Wait for the other one changing it */
		STARPU_PTHREAD_COND_WAIT(&init_cond, &init_mutex);
	init_count++;
	if (initialized == INITIALIZED)
	{
		/* He initialized it, don't do it again, and let the others get the mutex */
		STARPU_PTHREAD_MUTEX_UNLOCK(&init_mutex);
		return 0;
	}
	/* initialized == UNINITIALIZED */
	initialized = CHANGING;
	STARPU_PTHREAD_MUTEX_UNLOCK(&init_mutex);

#if defined(_WIN32) && !defined(__CYGWIN__)
	WSADATA wsadata;
	WSAStartup(MAKEWORD(1,0), &wsadata);
#endif

	srand(2008);

#ifdef HAVE_AYUDAME_H
#ifndef AYU_RT_STARPU
#define AYU_RT_STARPU 4
#endif
	if (AYU_event)
	{
		enum ayu_runtime_t ayu_rt = AYU_RT_STARPU;
		AYU_event(AYU_PREINIT, 0, (void*) &ayu_rt);
	}
#endif
	/* store the pointer to the user explicit configuration during the
	 * initialization */
	if (user_conf == NULL)
	{
	     struct starpu_conf *conf = malloc(sizeof(struct starpu_conf));
	     starpu_conf_init(conf);
	     config.conf = conf;
	     config.default_conf = 1;
	}
	else
	{
	     if (user_conf->magic != 42)
	     {
		  _STARPU_DISP("starpu_conf structure needs to be initialized with starpu_conf_init\n");
		  return -EINVAL;
	     }
	     config.conf = user_conf;
	     config.default_conf = 0;
	}

	_starpu_conf_check_environment(config.conf);

	_starpu_init_all_sched_ctxs(&config);
	_starpu_init_progression_hooks();

	_starpu_init_tags();

#ifdef STARPU_USE_FXT
	_starpu_init_fxt_profiling(config.conf->trace_buffer_size);
#endif

	_starpu_open_debug_logfile();

	_starpu_data_interface_init();

	_starpu_timing_init();

	_starpu_profiling_init();

	_starpu_load_bus_performance_files();

	/* Depending on whether we are a MP sink or not, we must build the
	 * topology with MP nodes or not. */
	ret = _starpu_build_topology(&config, is_a_sink);
	if (ret)
	{
		starpu_perfmodel_free_sampling_directories();
		STARPU_PTHREAD_MUTEX_LOCK(&init_mutex);
		init_count--;

		_starpu_destroy_machine_config(&config);

#ifdef STARPU_USE_SCC
		if (_starpu_scc_common_is_mp_initialized())
			_starpu_scc_src_mp_deinit();
#endif
		initialized = UNINITIALIZED;
		/* Let somebody else try to do it */
		STARPU_PTHREAD_COND_SIGNAL(&init_cond);
		STARPU_PTHREAD_MUTEX_UNLOCK(&init_mutex);
		return ret;
	}

	/* Allocate swap, if any */
	_starpu_swap_init();

	/* We need to store the current task handled by the different
	 * threads */
	_starpu_initialize_current_task_key();

	for (worker = 0; worker < config.topology.nworkers; worker++)
		_starpu_worker_init(&config.workers[worker], &config);

	STARPU_PTHREAD_KEY_CREATE(&worker_key, NULL);
	STARPU_PTHREAD_KEY_CREATE(&worker_set_key, NULL);

	_starpu_build_tree();

	if (!is_a_sink)
	{
		struct starpu_sched_policy *selected_policy = _starpu_select_sched_policy(&config, config.conf->sched_policy_name);
		_starpu_create_sched_ctx(selected_policy, NULL, -1, 1, "init", (config.conf->global_sched_ctx_min_priority != -1), config.conf->global_sched_ctx_min_priority, (config.conf->global_sched_ctx_min_priority != -1), config.conf->global_sched_ctx_max_priority, 1, config.conf->sched_policy_init);
	}

	_starpu_initialize_registered_performance_models();

	/* Launch "basic" workers (ie. non-combined workers) */
	if (!is_a_sink)
		_starpu_launch_drivers(&config);

	_starpu_watchdog_init();

	STARPU_PTHREAD_MUTEX_LOCK(&init_mutex);
	initialized = INITIALIZED;
	/* Tell everybody that we initialized */
	STARPU_PTHREAD_COND_BROADCAST(&init_cond);
	STARPU_PTHREAD_MUTEX_UNLOCK(&init_mutex);

	_STARPU_DEBUG("Initialisation finished\n");

#ifdef STARPU_USE_MP
	/* Finally, if we are a MP sink, we never leave this function. Else,
	 * we enter an infinite event loop which listen for MP commands from
	 * the source. */
	if (is_a_sink)
	{
		_starpu_sink_common_worker();

		/* We should normally never leave the loop as we don't want to
		 * really initialize STARPU */
		STARPU_ASSERT(0);
	}
#endif

	return 0;
}

/*
 * Handle runtime termination
 */

static void _starpu_terminate_workers(struct _starpu_machine_config *pconfig)
{
	int status = 0;
	unsigned workerid;
	unsigned n;

	for (workerid = 0; workerid < pconfig->topology.nworkers; workerid++)
	{
		starpu_wake_all_blocked_workers();

		_STARPU_DEBUG("wait for worker %u\n", workerid);

		struct _starpu_worker_set *set = pconfig->workers[workerid].set;
		struct _starpu_worker *worker = &pconfig->workers[workerid];

		/* in case StarPU termination code is called from a callback,
 		 * we have to check if pthread_self() is the worker itself */
		if (set)
		{
			if (set->started)
			{
#ifdef STARPU_SIMGRID
				status = starpu_pthread_join(set->worker_thread, NULL);
#else
				if (!pthread_equal(pthread_self(), set->worker_thread))
					status = starpu_pthread_join(set->worker_thread, NULL);
#endif
				if (status)
				{
#ifdef STARPU_VERBOSE
					_STARPU_DEBUG("starpu_pthread_join -> %d\n", status);
#endif
				}
				set->started = 0;
			}
		}
		else
		{
			if (!worker->run_by_starpu)
				goto out;

#ifdef STARPU_SIMGRID
			status = starpu_pthread_join(worker->worker_thread, NULL);
#else
			if (!pthread_equal(pthread_self(), worker->worker_thread))
				status = starpu_pthread_join(worker->worker_thread, NULL);
#endif
			if (status)
			{
#ifdef STARPU_VERBOSE
				_STARPU_DEBUG("starpu_pthread_join -> %d\n", status);
#endif
			}
		}

out:
		STARPU_ASSERT(starpu_task_list_empty(&worker->local_tasks));
		for (n = 0; n < worker->local_ordered_tasks_size; n++)
			STARPU_ASSERT(worker->local_ordered_tasks[n] == NULL);
		_starpu_sched_ctx_list_delete(&worker->sched_ctx_list);
		free(worker->local_ordered_tasks);
	}
}

/* Condition variable and mutex used to pause/resume. */
static starpu_pthread_cond_t pause_cond = STARPU_PTHREAD_COND_INITIALIZER;
static starpu_pthread_mutex_t pause_mutex = STARPU_PTHREAD_MUTEX_INITIALIZER;

void _starpu_may_pause(void)
{
	/* pause_depth is just protected by a memory barrier */
	STARPU_RMB();

	if (STARPU_UNLIKELY(config.pause_depth > 0))
	{
		STARPU_PTHREAD_MUTEX_LOCK(&pause_mutex);
		if (config.pause_depth > 0)
		{
			STARPU_PTHREAD_COND_WAIT(&pause_cond, &pause_mutex);
		}
		STARPU_PTHREAD_MUTEX_UNLOCK(&pause_mutex);
	}
}

unsigned _starpu_machine_is_running(void)
{
	unsigned ret;
	/* running is just protected by a memory barrier */
	STARPU_RMB();

	ANNOTATE_HAPPENS_AFTER(&config.running);
	ret = config.running;
	ANNOTATE_HAPPENS_BEFORE(&config.running);
	return ret;
}

void starpu_pause()
{
	STARPU_HG_DISABLE_CHECKING(config.pause_depth);
	config.pause_depth += 1;
}

void starpu_resume()
{
	STARPU_PTHREAD_MUTEX_LOCK(&pause_mutex);
	config.pause_depth -= 1;
	if (!config.pause_depth)
	{
		STARPU_PTHREAD_COND_BROADCAST(&pause_cond);
	}
	STARPU_PTHREAD_MUTEX_UNLOCK(&pause_mutex);
}

unsigned _starpu_worker_can_block(unsigned memnode STARPU_ATTRIBUTE_UNUSED, struct _starpu_worker *worker STARPU_ATTRIBUTE_UNUSED)
{
#ifdef STARPU_NON_BLOCKING_DRIVERS
	return 0;
#else
	unsigned can_block = 1;

	struct starpu_driver driver;
	driver.type = worker->arch;
	switch (driver.type)
	{
	case STARPU_CPU_WORKER:
		driver.id.cpu_id = worker->devid;
		break;
	case STARPU_CUDA_WORKER:
		driver.id.cuda_id = worker->devid;
		break;
#ifdef STARPU_USE_OPENCL
	case STARPU_OPENCL_WORKER:
		starpu_opencl_get_device(worker->devid, &driver.id.opencl_id);
		break;
#endif
	default:
		goto always_launch;
	}
	if (!_starpu_may_launch_driver(config.conf, &driver))
		return 0;

always_launch:

#ifndef STARPU_SIMGRID
	if (!_starpu_check_that_no_data_request_exists(memnode))
		can_block = 0;
#endif

	if (!_starpu_machine_is_running())
		can_block = 0;

	if (!_starpu_execute_registered_progression_hooks())
		can_block = 0;

	return can_block;
#endif
}

static void _starpu_kill_all_workers(struct _starpu_machine_config *pconfig)
{
	/* set the flag which will tell workers to stop */
	ANNOTATE_HAPPENS_AFTER(&config.running);
	pconfig->running = 0;
	/* running is just protected by a memory barrier */
	ANNOTATE_HAPPENS_BEFORE(&config.running);
	STARPU_WMB();
	starpu_wake_all_blocked_workers();
}

void starpu_display_stats()
{
	starpu_profiling_bus_helper_display_summary();
	starpu_profiling_worker_helper_display_summary();
}

void starpu_shutdown(void)
{
	STARPU_PTHREAD_MUTEX_LOCK(&init_mutex);
	init_count--;
	STARPU_ASSERT_MSG(init_count >= 0, "Number of calls to starpu_shutdown() can not be higher than the number of calls to starpu_init()\n");
	if (init_count)
	{
		_STARPU_DEBUG("Still somebody needing StarPU, don't deinitialize\n");
		STARPU_PTHREAD_MUTEX_UNLOCK(&init_mutex);
		return;
	}

	/* We're last */
	initialized = CHANGING;
	STARPU_PTHREAD_MUTEX_UNLOCK(&init_mutex);

	/* If the workers are frozen, no progress can be made. */
	STARPU_ASSERT(config.pause_depth <= 0);

	starpu_task_wait_for_no_ready();

	/* tell all workers to shutdown */
	_starpu_kill_all_workers(&config);

	{
	     int stats = starpu_get_env_number("STARPU_STATS");
	     if (stats != 0)
	     {
		  _starpu_display_msi_stats();
		  _starpu_display_alloc_cache_stats();
		  _starpu_display_comm_amounts();
	     }
	}

	starpu_profiling_bus_helper_display_summary();
	starpu_profiling_worker_helper_display_summary();

	_starpu_deinitialize_current_task_key();
	_starpu_deinitialize_registered_performance_models();

	_starpu_watchdog_shutdown();

	/* wait for their termination */
	_starpu_terminate_workers(&config);

	{
	     int stats = starpu_get_env_number("STARPU_MEMORY_STATS");
	     if (stats != 0)
	     {
		  // Display statistics on data which have not been unregistered
		  starpu_data_display_memory_stats();
	     }
	}

	_starpu_delete_all_sched_ctxs();
	_starpu_sched_component_workers_destroy();

	_starpu_disk_unregister();
#ifdef STARPU_HAVE_HWLOC
	starpu_tree_free(config.topology.tree);
	free(config.topology.tree);
#endif
	_starpu_destroy_topology(&config);
#ifdef STARPU_USE_FXT
	_starpu_stop_fxt_profiling();
#endif

	_starpu_data_interface_shutdown();

	/* Drop all remaining tags */
	_starpu_tag_clear();

#ifdef STARPU_OPENMP
	_starpu_omp_dummy_shutdown();
#endif
	_starpu_close_debug_logfile();

	STARPU_PTHREAD_KEY_DELETE(worker_key);
	STARPU_PTHREAD_KEY_DELETE(worker_set_key);

	STARPU_PTHREAD_MUTEX_LOCK(&init_mutex);
	initialized = UNINITIALIZED;
	/* Let someone else that wants to initialize it again do it */
	STARPU_PTHREAD_COND_SIGNAL(&init_cond);
	STARPU_PTHREAD_MUTEX_UNLOCK(&init_mutex);

	/* Clear memory if it was allocated by StarPU */
	if (config.default_conf)
	     free(config.conf);

#ifdef HAVE_AYUDAME_H
	if (AYU_event) AYU_event(AYU_FINISH, 0, NULL);
#endif

#ifdef STARPU_USE_SCC
	if (_starpu_scc_common_is_mp_initialized())
		_starpu_scc_src_mp_deinit();
#endif
	_starpu_print_idle_time();
	_STARPU_DEBUG("Shutdown finished\n");
}


unsigned starpu_worker_get_count(void)
{
	return config.topology.nworkers;
}

unsigned starpu_worker_is_blocked(int workerid)
{
	return config.workers[workerid].blocked;
}

unsigned starpu_worker_is_slave_somewhere(int workerid)
{
	return config.workers[workerid].is_slave_somewhere;
}

int starpu_worker_get_count_by_type(enum starpu_worker_archtype type)
{
	switch (type)
	{
		case STARPU_CPU_WORKER:
			return config.topology.ncpus;

		case STARPU_CUDA_WORKER:
			return config.topology.ncudagpus;

		case STARPU_OPENCL_WORKER:
			return config.topology.nopenclgpus;

		case STARPU_MIC_WORKER:
			return config.topology.nmicdevices;

		case STARPU_SCC_WORKER:
			return config.topology.nsccdevices;

		default:
			return -EINVAL;
	}
}

unsigned starpu_combined_worker_get_count(void)
{
	return config.topology.ncombinedworkers;
}

unsigned starpu_cpu_worker_get_count(void)
{
	return config.topology.ncpus;
}

unsigned starpu_cuda_worker_get_count(void)
{
	return config.topology.ncudagpus;
}

unsigned starpu_opencl_worker_get_count(void)
{
	return config.topology.nopenclgpus;
}

int starpu_asynchronous_copy_disabled(void)
{
	return config.conf->disable_asynchronous_copy;
}

int starpu_asynchronous_cuda_copy_disabled(void)
{
	return config.conf->disable_asynchronous_cuda_copy;
}

int starpu_asynchronous_opencl_copy_disabled(void)
{
	return config.conf->disable_asynchronous_opencl_copy;
}

int starpu_asynchronous_mic_copy_disabled(void)
{
	return config.conf->disable_asynchronous_mic_copy;
}

unsigned starpu_mic_worker_get_count(void)
{
	int i = 0, count = 0;

	for (i = 0; i < STARPU_MAXMICDEVS; i++)
		count += config.topology.nmiccores[i];

	return count;
}

unsigned starpu_scc_worker_get_count(void)
{
	return config.topology.nsccdevices;
}

/* When analyzing performance, it is useful to see what is the processing unit
 * that actually performed the task. This function returns the id of the
 * processing unit actually executing it, therefore it makes no sense to use it
 * within the callbacks of SPU functions for instance. If called by some thread
 * that is not controlled by StarPU, starpu_worker_get_id returns -1. */
int starpu_worker_get_id(void)
{
	struct _starpu_worker * worker;

	worker = _starpu_get_local_worker_key();
	if (worker)
	{
		return worker->workerid;
	}
	else
	{
		/* there is no worker associated to that thread, perhaps it is
		 * a thread from the application or this is some SPU worker */
		return -1;
	}
}

int starpu_combined_worker_get_id(void)
{
	struct _starpu_worker *worker;

	worker = _starpu_get_local_worker_key();
	if (worker)
	{
		return worker->combined_workerid;
	}
	else
	{
		/* there is no worker associated to that thread, perhaps it is
		 * a thread from the application or this is some SPU worker */
		return -1;
	}
}

int starpu_combined_worker_get_size(void)
{
	struct _starpu_worker *worker;

	worker = _starpu_get_local_worker_key();
	if (worker)
	{
		return worker->worker_size;
	}
	else
	{
		/* there is no worker associated to that thread, perhaps it is
		 * a thread from the application or this is some SPU worker */
		return -1;
	}
}

int starpu_combined_worker_get_rank(void)
{
	struct _starpu_worker *worker;

	worker = _starpu_get_local_worker_key();
	if (worker)
	{
		return worker->current_rank;
	}
	else
	{
		/* there is no worker associated to that thread, perhaps it is
		 * a thread from the application or this is some SPU worker */
		return -1;
	}
}

int starpu_worker_get_subworkerid(int id)
{
	return config.workers[id].subworkerid;
}

int starpu_worker_get_devid(int id)
{
	return config.workers[id].devid;
}

struct _starpu_worker *_starpu_get_worker_struct(unsigned id)
{
	return &config.workers[id];
}

unsigned starpu_worker_is_combined_worker(int id)
{
	return id >= (int)config.topology.nworkers;
}

struct _starpu_sched_ctx *_starpu_get_sched_ctx_struct(unsigned id)
{
	if(id == STARPU_NMAX_SCHED_CTXS) return NULL;
	return &config.sched_ctxs[id];
}

struct _starpu_combined_worker *_starpu_get_combined_worker_struct(unsigned id)
{
	unsigned basic_worker_count = starpu_worker_get_count();

	//_STARPU_DEBUG("basic_worker_count:%d\n",basic_worker_count);

	STARPU_ASSERT(id >= basic_worker_count);
	return &config.combined_workers[id - basic_worker_count];
}

enum starpu_worker_archtype starpu_worker_get_type(int id)
{
	return config.workers[id].arch;
}

int starpu_worker_get_ids_by_type(enum starpu_worker_archtype type, int *workerids, int maxsize)
{
	unsigned nworkers = starpu_worker_get_count();

	int cnt = 0;

	unsigned id;
	for (id = 0; id < nworkers; id++)
	{
		if (starpu_worker_get_type(id) == type)
		{
			/* Perhaps the array is too small ? */
			if (cnt >= maxsize)
				return -ERANGE;

			workerids[cnt++] = id;
		}
	}

	return cnt;
}

int starpu_worker_get_by_type(enum starpu_worker_archtype type, int num)
{
	unsigned nworkers = starpu_worker_get_count();

	int cnt = 0;

	unsigned id;
	for (id = 0; id < nworkers; id++)
	{
		if (starpu_worker_get_type(id) == type)
		{
			if (num == cnt)
				return id;
			cnt++;
		}
	}

	/* Not found */
	return -1;
}

int starpu_worker_get_by_devid(enum starpu_worker_archtype type, int devid)
{
	unsigned nworkers = starpu_worker_get_count();

	unsigned id;
	for (id = 0; id < nworkers; id++)
		if (starpu_worker_get_type(id) == type && starpu_worker_get_devid(id) == devid)
			return id;

	/* Not found */
	return -1;
}

void starpu_worker_get_name(int id, char *dst, size_t maxlen)
{
	char *name = config.workers[id].name;

	snprintf(dst, maxlen, "%s", name);
}

int starpu_worker_get_bindid(int workerid)
{
	return config.workers[workerid].bindid;
}

int _starpu_worker_get_workerids(int bindid, int *workerids)
{
	unsigned nworkers = starpu_worker_get_count();
	int nw = 0;
	unsigned id;
	for (id = 0; id < nworkers; id++)
		if (config.workers[id].bindid == bindid)
			workerids[nw++] = id;
	return nw;
}

/* Retrieve the status which indicates what the worker is currently doing. */
enum _starpu_worker_status _starpu_worker_get_status(int workerid)
{
	return config.workers[workerid].status;
}

/* Change the status of the worker which indicates what the worker is currently
 * doing (eg. executing a callback). */
void _starpu_worker_set_status(int workerid, enum _starpu_worker_status status)
{
	config.workers[workerid].status = status;
}

void starpu_worker_get_sched_condition(int workerid, starpu_pthread_mutex_t **sched_mutex, starpu_pthread_cond_t **sched_cond)
{
	*sched_cond = &config.workers[workerid].sched_cond;
	*sched_mutex = &config.workers[workerid].sched_mutex;
}

int starpu_wakeup_worker(int workerid, starpu_pthread_cond_t *cond, starpu_pthread_mutex_t *mutex)
{
	int success = 0;
	STARPU_PTHREAD_MUTEX_LOCK(mutex);
	if (config.workers[workerid].status == STATUS_SLEEPING)
	{
		config.workers[workerid].status = STATUS_WAKING_UP;
		STARPU_PTHREAD_COND_SIGNAL(cond);
		success = 1;
	}
	STARPU_PTHREAD_MUTEX_UNLOCK(mutex);
	return success;
}

int starpu_wake_worker(int workerid)
{
	starpu_pthread_mutex_t *sched_mutex;
	starpu_pthread_cond_t *sched_cond;
	starpu_worker_get_sched_condition(workerid, &sched_mutex, &sched_cond);
	return starpu_wakeup_worker(workerid, sched_cond, sched_mutex);
}


int starpu_worker_get_nids_by_type(enum starpu_worker_archtype type, int *workerids, int maxsize)
{
	unsigned nworkers = starpu_worker_get_count();

	int cnt = 0;

	unsigned id;
	for (id = 0; id < nworkers; id++)
	{
		if (starpu_worker_get_type(id) == type)
		{
			/* Perhaps the array is too small ? */
			if (cnt >= maxsize)
				return cnt;

			workerids[cnt++] = id;
		}
	}

	return cnt;
}

int starpu_worker_get_nids_ctx_free_by_type(enum starpu_worker_archtype type, int *workerids, int maxsize)
{
	unsigned nworkers = starpu_worker_get_count();

	int cnt = 0;

	unsigned id, worker;
	unsigned found = 0;
	for (id = 0; id < nworkers; id++)
	{
		found = 0;
		if (starpu_worker_get_type(id) == type)
		{
			/* Perhaps the array is too small ? */
			if (cnt >= maxsize)
				return cnt;
			int s;
			for(s = 1; s < STARPU_NMAX_SCHED_CTXS; s++)
			{
				if(config.sched_ctxs[s].id != STARPU_NMAX_SCHED_CTXS)
				{
					struct starpu_worker_collection *workers = config.sched_ctxs[s].workers;
					struct starpu_sched_ctx_iterator it;

					workers->init_iterator(workers, &it);
					while(workers->has_next(workers, &it))
					{
						worker = workers->get_next(workers, &it);
						if(worker == id)
						{
							found = 1;
							break;
						}
					}

					if(found) break;
				}
			}
			if(!found)
				workerids[cnt++] = id;
		}
	}

	return cnt;
}


struct _starpu_sched_ctx* _starpu_get_initial_sched_ctx(void)
{
	return &config.sched_ctxs[STARPU_GLOBAL_SCHED_CTX];
}

int _starpu_worker_get_nsched_ctxs(int workerid)
{
	return config.workers[workerid].nsched_ctxs;
}

static void *
_starpu_get_worker_from_driver(struct starpu_driver *d)
{
	unsigned nworkers = starpu_worker_get_count();
	unsigned workerid;

#ifdef STARPU_USE_CUDA
	if (d->type == STARPU_CUDA_WORKER)
		return &cuda_worker_set[d->id.cuda_id];
#endif

	for (workerid = 0; workerid < nworkers; workerid++)
	{
		if (starpu_worker_get_type(workerid) == d->type)
		{
			struct _starpu_worker *worker;
			worker = _starpu_get_worker_struct(workerid);
			switch (d->type)
			{
#ifdef STARPU_USE_CPU
			case STARPU_CPU_WORKER:
				if (worker->devid == d->id.cpu_id)
					return worker;
				break;
#endif
#ifdef STARPU_USE_OPENCL
			case STARPU_OPENCL_WORKER:
			{
				cl_device_id device;
				starpu_opencl_get_device(worker->devid, &device);
				if (device == d->id.opencl_id)
					return worker;
				break;
			}
#endif
			default:
				_STARPU_DEBUG("Invalid device type\n");
				return NULL;
			}
		}
	}

	return NULL;
}

int
starpu_driver_run(struct starpu_driver *d)
{
	if (!d)
	{
		_STARPU_DEBUG("Invalid argument\n");
		return -EINVAL;
	}

	void *worker = _starpu_get_worker_from_driver(d);

	switch (d->type)
	{
#ifdef STARPU_USE_CPU
	case STARPU_CPU_WORKER:
		return _starpu_run_cpu(worker);
#endif
#ifdef STARPU_USE_CUDA
	case STARPU_CUDA_WORKER:
		return _starpu_run_cuda(worker);
#endif
#ifdef STARPU_USE_OPENCL
	case STARPU_OPENCL_WORKER:
		return _starpu_run_opencl(worker);
#endif
	default:
		_STARPU_DEBUG("Invalid device type\n");
		return -EINVAL;
	}
}

int
starpu_driver_init(struct starpu_driver *d)
{
	STARPU_ASSERT(d);
	void *worker = _starpu_get_worker_from_driver(d);

	switch (d->type)
	{
#ifdef STARPU_USE_CPU
	case STARPU_CPU_WORKER:
		return _starpu_cpu_driver_init(worker);
#endif
#ifdef STARPU_USE_CUDA
	case STARPU_CUDA_WORKER:
		return _starpu_cuda_driver_init(worker);
#endif
#ifdef STARPU_USE_OPENCL
	case STARPU_OPENCL_WORKER:
		return _starpu_opencl_driver_init(worker);
#endif
	default:
		return -EINVAL;
	}
}

int
starpu_driver_run_once(struct starpu_driver *d)
{
	STARPU_ASSERT(d);
	void *worker = _starpu_get_worker_from_driver(d);

	switch (d->type)
	{
#ifdef STARPU_USE_CPU
	case STARPU_CPU_WORKER:
		return _starpu_cpu_driver_run_once(worker);
#endif
#ifdef STARPU_USE_CUDA
	case STARPU_CUDA_WORKER:
		return _starpu_cuda_driver_run_once(worker);
#endif
#ifdef STARPU_USE_OPENCL
	case STARPU_OPENCL_WORKER:
		return _starpu_opencl_driver_run_once(worker);
#endif
	default:
		return -EINVAL;
	}
}

int
starpu_driver_deinit(struct starpu_driver *d)
{
	STARPU_ASSERT(d);
	void *worker = _starpu_get_worker_from_driver(d);

	switch (d->type)
	{
#ifdef STARPU_USE_CPU
	case STARPU_CPU_WORKER:
		return _starpu_cpu_driver_deinit(worker);
#endif
#ifdef STARPU_USE_CUDA
	case STARPU_CUDA_WORKER:
		return _starpu_cuda_driver_deinit(worker);
#endif
#ifdef STARPU_USE_OPENCL
	case STARPU_OPENCL_WORKER:
		return _starpu_opencl_driver_deinit(worker);
#endif
	default:
		return -EINVAL;
	}
}

void starpu_get_version(int *major, int *minor, int *release)
{
	*major = STARPU_MAJOR_VERSION;
	*minor = STARPU_MINOR_VERSION;
	*release = STARPU_RELEASE_VERSION;
}

void _starpu_unlock_mutex_if_prev_locked()
{
	int workerid = starpu_worker_get_id();
	if(workerid != -1)
	{
		struct _starpu_worker *w = _starpu_get_worker_struct(workerid);
		if(w->sched_mutex_locked)
		{
			STARPU_PTHREAD_MUTEX_UNLOCK(&w->sched_mutex);
			_starpu_worker_set_flag_sched_mutex_locked(workerid, 1);
		}
	}
	return;
}

void _starpu_relock_mutex_if_prev_locked()
{
	int workerid = starpu_worker_get_id();
	if(workerid != -1)
	{
		struct _starpu_worker *w = _starpu_get_worker_struct(workerid);
		if(w->sched_mutex_locked)
			STARPU_PTHREAD_MUTEX_LOCK(&w->sched_mutex);
	}
	return;
}

void _starpu_worker_set_flag_sched_mutex_locked(int workerid, unsigned flag)
{
	struct _starpu_worker *w = _starpu_get_worker_struct(workerid);
	w->sched_mutex_locked = flag;
}

unsigned _starpu_worker_mutex_is_sched_mutex(int workerid, starpu_pthread_mutex_t *mutex)
{
	struct _starpu_worker *w = _starpu_get_worker_struct(workerid);
	return &w->sched_mutex == mutex;
}

unsigned starpu_worker_get_sched_ctx_list(int workerid, unsigned **sched_ctxs)
{
	unsigned s = 0;
	unsigned nsched_ctxs = _starpu_worker_get_nsched_ctxs(workerid);
	*sched_ctxs = (unsigned*)malloc(nsched_ctxs*sizeof(unsigned));
	struct _starpu_worker *worker = _starpu_get_worker_struct(workerid);
	struct _starpu_sched_ctx_list *l = NULL;
	for (l = worker->sched_ctx_list; l; l = l->next)
	{
		(*sched_ctxs)[s++] = l->sched_ctx;
	}
	return nsched_ctxs;
}

char *starpu_worker_get_type_as_string(enum starpu_worker_archtype type)
{
	if (type == STARPU_CPU_WORKER) return "STARPU_CPU_WORKER";
	if (type == STARPU_CUDA_WORKER) return "STARPU_CUDA_WORKER";
	if (type == STARPU_OPENCL_WORKER) return "STARPU_OPENCL_WORKER";
	if (type == STARPU_MIC_WORKER) return "STARPU_MIC_WORKER";
	if (type == STARPU_SCC_WORKER) return "STARPU_SCC_WORKER";
	if (type == STARPU_ANY_WORKER) return "STARPU_ANY_WORKER";
	return "STARPU_unknown_WORKER";
}