/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
-#include <atomic>
-
-#include "src/internal_config.h"
-#if HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-
-#ifndef _WIN32
-#include <sys/syscall.h>
-#endif
-
-#if HAVE_FUTEX_H
-#include <linux/futex.h>
-#include <limits.h>
-#endif
-
-#include "xbt/parmap.h"
#include "xbt/log.h"
-#include "xbt/function_types.h"
-#include "xbt/dynar.h"
-#include "xbt/xbt_os_thread.h"
-#include "xbt/sysdep.h"
-#include "src/simix/smx_private.h"
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_parmap, xbt, "parmap: parallel map");
-
-typedef enum {
- XBT_PARMAP_WORK,
- XBT_PARMAP_DESTROY
-} e_xbt_parmap_flag_t;
-
-static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode);
-static void *xbt_parmap_worker_main(void *parmap);
-static void xbt_parmap_work(xbt_parmap_t parmap);
-
-static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap);
-static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap);
-static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap);
-static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round);
-
-#if HAVE_FUTEX_H
-static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap);
-static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap);
-static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap);
-static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round);
-static void futex_wait(unsigned *uaddr, unsigned val);
-static void futex_wake(unsigned *uaddr, unsigned val);
-#endif
-
-static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap);
-static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap);
-static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap);
-static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round);
-
-/**
- * \brief Parallel map structure
- */
-typedef struct s_xbt_parmap {
- e_xbt_parmap_flag_t status; /**< is the parmap active or being destroyed? */
- unsigned work; /**< index of the current round */
- unsigned thread_counter; /**< number of workers that have done the work */
-
- unsigned int num_workers; /**< total number of worker threads including the controller */
- xbt_os_thread_t *workers; /**< worker thread handlers */
- void_f_pvoid_t fun; /**< function to run in parallel on each element of data */
- xbt_dynar_t data; /**< parameters to pass to fun in parallel */
- std::atomic<unsigned int> index; /**< index of the next element of data to pick */
-
- /* posix only */
- xbt_os_cond_t ready_cond;
- xbt_os_mutex_t ready_mutex;
- xbt_os_cond_t done_cond;
- xbt_os_mutex_t done_mutex;
-
- /* fields that depend on the synchronization mode */
- e_xbt_parmap_mode_t mode; /**< synchronization mode */
- void (*master_wait_f)(xbt_parmap_t); /**< wait for the workers to have done the work */
- void (*worker_signal_f)(xbt_parmap_t); /**< signal the master that a worker has done the work */
- void (*master_signal_f)(xbt_parmap_t); /**< wakes the workers threads to process tasks */
- void (*worker_wait_f)(xbt_parmap_t, unsigned); /**< waits for more work */
-} s_xbt_parmap_t;
-
-/**
- * \brief Thread data transmission structure
- */
-typedef struct s_xbt_parmap_thread_data{
- xbt_parmap_t parmap;
- int worker_id;
-} s_xbt_parmap_thread_data_t;
-
-typedef s_xbt_parmap_thread_data_t *xbt_parmap_thread_data_t;
-
-/**
- * \brief Creates a parallel map object
- * \param num_workers number of worker threads to create
- * \param mode how to synchronize the worker threads
- * \return the parmap created
- */
-xbt_parmap_t xbt_parmap_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
-{
- XBT_DEBUG("Create new parmap (%u workers)", num_workers);
-
- /* Initialize the thread pool data structure */
- xbt_parmap_t parmap = new s_xbt_parmap_t();
- parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
-
- parmap->num_workers = num_workers;
- parmap->status = XBT_PARMAP_WORK;
- xbt_parmap_set_mode(parmap, mode);
-
- /* Create the pool of worker threads */
- xbt_parmap_thread_data_t data;
- parmap->workers[0] = nullptr;
-#if HAVE_PTHREAD_SETAFFINITY
- int core_bind = 0;
-#endif
- for (unsigned int i = 1; i < num_workers; i++) {
- data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
- data->parmap = parmap;
- data->worker_id = i;
- parmap->workers[i] = xbt_os_thread_create(nullptr, xbt_parmap_worker_main, data, nullptr);
-#if HAVE_PTHREAD_SETAFFINITY
- xbt_os_thread_bind(parmap->workers[i], core_bind);
- if (core_bind != xbt_os_get_numcores() - 1)
- core_bind++;
- else
- core_bind = 0;
-#endif
- }
- return parmap;
-}
-
-/**
- * \brief Destroys a parmap
- * \param parmap the parmap to destroy
- */
-void xbt_parmap_destroy(xbt_parmap_t parmap)
-{
- if (!parmap) {
- return;
- }
-
- parmap->status = XBT_PARMAP_DESTROY;
- parmap->master_signal_f(parmap);
-
- unsigned int i;
- for (i = 1; i < parmap->num_workers; i++)
- xbt_os_thread_join(parmap->workers[i], nullptr);
-
- xbt_os_cond_destroy(parmap->ready_cond);
- xbt_os_mutex_destroy(parmap->ready_mutex);
- xbt_os_cond_destroy(parmap->done_cond);
- xbt_os_mutex_destroy(parmap->done_mutex);
-
- xbt_free(parmap->workers);
- delete parmap;
-}
-
-/**
- * \brief Sets the synchronization mode of a parmap.
- * \param parmap a parallel map object
- * \param mode the synchronization mode
- */
-static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode)
-{
- if (mode == XBT_PARMAP_DEFAULT) {
-#if HAVE_FUTEX_H
- mode = XBT_PARMAP_FUTEX;
-#else
- mode = XBT_PARMAP_POSIX;
-#endif
- }
- parmap->mode = mode;
-
- switch (mode) {
- case XBT_PARMAP_POSIX:
- parmap->master_wait_f = &xbt_parmap_posix_master_wait;
- parmap->worker_signal_f = &xbt_parmap_posix_worker_signal;
- parmap->master_signal_f = &xbt_parmap_posix_master_signal;
- parmap->worker_wait_f = &xbt_parmap_posix_worker_wait;
-
- parmap->ready_cond = xbt_os_cond_init();
- parmap->ready_mutex = xbt_os_mutex_init();
- parmap->done_cond = xbt_os_cond_init();
- parmap->done_mutex = xbt_os_mutex_init();
- break;
- case XBT_PARMAP_FUTEX:
-#if HAVE_FUTEX_H
- parmap->master_wait_f = &xbt_parmap_futex_master_wait;
- parmap->worker_signal_f = &xbt_parmap_futex_worker_signal;
- parmap->master_signal_f = &xbt_parmap_futex_master_signal;
- parmap->worker_wait_f = &xbt_parmap_futex_worker_wait;
-
- xbt_os_cond_destroy(parmap->ready_cond);
- xbt_os_mutex_destroy(parmap->ready_mutex);
- xbt_os_cond_destroy(parmap->done_cond);
- xbt_os_mutex_destroy(parmap->done_mutex);
- break;
-#else
- xbt_die("Futex is not available on this OS.");
-#endif
- case XBT_PARMAP_BUSY_WAIT:
- parmap->master_wait_f = &xbt_parmap_busy_master_wait;
- parmap->worker_signal_f = &xbt_parmap_busy_worker_signal;
- parmap->master_signal_f = &xbt_parmap_busy_master_signal;
- parmap->worker_wait_f = &xbt_parmap_busy_worker_wait;
-
- xbt_os_cond_destroy(parmap->ready_cond);
- xbt_os_mutex_destroy(parmap->ready_mutex);
- xbt_os_cond_destroy(parmap->done_cond);
- xbt_os_mutex_destroy(parmap->done_mutex);
- break;
- case XBT_PARMAP_DEFAULT:
- THROW_IMPOSSIBLE;
- break;
- default:
- THROW_IMPOSSIBLE;
- }
-}
-
-/**
- * \brief Applies a list of tasks in parallel.
- * \param parmap a parallel map object
- * \param fun the function to call in parallel
- * \param data each element of this dynar will be passed as an argument to fun
- */
-void xbt_parmap_apply(xbt_parmap_t parmap, void_f_pvoid_t fun, xbt_dynar_t data)
-{
- /* Assign resources to worker threads (we are maestro here)*/
- parmap->fun = fun;
- parmap->data = data;
- parmap->index = 0;
- parmap->master_signal_f(parmap); // maestro runs futex_wait to wake all the minions (the working threads)
- xbt_parmap_work(parmap); // maestro works with its minions
- parmap->master_wait_f(parmap); // When there is no more work to do, then maestro waits for the last minion to stop
- XBT_DEBUG("Job done"); // ... and proceeds
-}
-
-/**
- * \brief Returns a next task to process.
- *
- * Worker threads call this function to get more work.
- *
- * \return the next task to process, or nullptr if there is no more work
- */
-void* xbt_parmap_next(xbt_parmap_t parmap)
-{
- unsigned int index = parmap->index++;
- if (index < xbt_dynar_length(parmap->data)) {
- return xbt_dynar_get_as(parmap->data, index, void*);
- }
- return nullptr;
-}
-
-static void xbt_parmap_work(xbt_parmap_t parmap)
-{
- unsigned int index = parmap->index++;
- while (index < xbt_dynar_length(parmap->data)){
- parmap->fun(xbt_dynar_get_as(parmap->data, index, void*));
- index = parmap->index++;
- }
-}
-
-/**
- * \brief Main function of a worker thread.
- * \param arg the parmap
- */
-static void *xbt_parmap_worker_main(void *arg)
-{
- xbt_parmap_thread_data_t data = static_cast<xbt_parmap_thread_data_t>(arg);
- xbt_parmap_t parmap = data->parmap;
- unsigned round = 0;
- smx_context_t context = SIMIX_context_new(std::function<void()>(), nullptr, nullptr);
- SIMIX_context_set_current(context);
-
- XBT_DEBUG("New worker thread created");
-
- /* Worker's main loop */
- while (1) {
- round++;
- parmap->worker_wait_f(parmap, round);
- if (parmap->status == XBT_PARMAP_WORK) {
- XBT_DEBUG("Worker %d got a job", data->worker_id);
-
- xbt_parmap_work(parmap);
- parmap->worker_signal_f(parmap);
-
- XBT_DEBUG("Worker %d has finished", data->worker_id);
- /* We are destroying the parmap */
- } else {
- delete context;
- xbt_free(data);
- return nullptr;
- }
- }
-}
-
-#if HAVE_FUTEX_H
-static void futex_wait(unsigned *uaddr, unsigned val)
-{
- XBT_VERB("Waiting on futex %p", uaddr);
- syscall(SYS_futex, uaddr, FUTEX_WAIT_PRIVATE, val, nullptr, nullptr, 0);
-}
-
-static void futex_wake(unsigned *uaddr, unsigned val)
-{
- XBT_VERB("Waking futex %p", uaddr);
- syscall(SYS_futex, uaddr, FUTEX_WAKE_PRIVATE, val, nullptr, nullptr, 0);
-}
-#endif
-
-/**
- * \brief Starts the parmap: waits for all workers to be ready and returns.
- *
- * This function is called by the controller thread.
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap)
-{
- xbt_os_mutex_acquire(parmap->done_mutex);
- if (parmap->thread_counter < parmap->num_workers) {
- /* wait for all workers to be ready */
- xbt_os_cond_wait(parmap->done_cond, parmap->done_mutex);
- }
- xbt_os_mutex_release(parmap->done_mutex);
-}
-
-/**
- * \brief Ends the parmap: wakes the controller thread when all workers terminate.
- *
- * This function is called by all worker threads when they end (not including the controller).
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap)
-{
- xbt_os_mutex_acquire(parmap->done_mutex);
- parmap->thread_counter++;
- if (parmap->thread_counter == parmap->num_workers) {
- /* all workers have finished, wake the controller */
- xbt_os_cond_signal(parmap->done_cond);
- }
- xbt_os_mutex_release(parmap->done_mutex);
-}
-
-/**
- * \brief Wakes all workers and waits for them to finish the tasks.
- *
- * This function is called by the controller thread.
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap)
-{
- xbt_os_mutex_acquire(parmap->ready_mutex);
- parmap->thread_counter = 1;
- parmap->work++;
- /* wake all workers */
- xbt_os_cond_broadcast(parmap->ready_cond);
- xbt_os_mutex_release(parmap->ready_mutex);
-}
-
-/**
- * \brief Waits for some work to process.
- *
- * This function is called by each worker thread (not including the controller) when it has no more work to do.
- *
- * \param parmap a parmap
- * \param round the expected round number
- */
-static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round)
-{
- xbt_os_mutex_acquire(parmap->ready_mutex);
- /* wait for more work */
- if (parmap->work != round) {
- xbt_os_cond_wait(parmap->ready_cond, parmap->ready_mutex);
- }
- xbt_os_mutex_release(parmap->ready_mutex);
-}
-
-#if HAVE_FUTEX_H
-/**
- * \brief Starts the parmap: waits for all workers to be ready and returns.
- *
- * This function is called by the controller thread.
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap)
-{
- unsigned count = parmap->thread_counter;
- while (count < parmap->num_workers) {
- /* wait for all workers to be ready */
- futex_wait(&parmap->thread_counter, count);
- count = parmap->thread_counter;
- }
-}
-
-/**
- * \brief Ends the parmap: wakes the controller thread when all workers terminate.
- *
- * This function is called by all worker threads when they end (not including the controller).
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap)
-{
- unsigned count = __sync_add_and_fetch(&parmap->thread_counter, 1);
- if (count == parmap->num_workers) {
- /* all workers have finished, wake the controller */
- futex_wake(&parmap->thread_counter, INT_MAX);
- }
-}
-
-/**
- * \brief Wakes all workers and waits for them to finish the tasks.
- *
- * This function is called by the controller thread.
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap)
-{
- parmap->thread_counter = 1;
- __sync_add_and_fetch(&parmap->work, 1);
- /* wake all workers */
- futex_wake(&parmap->work, INT_MAX);
-}
-
-/**
- * \brief Waits for some work to process.
- *
- * This function is called by each worker thread (not including the controller) when it has no more work to do.
- *
- * \param parmap a parmap
- * \param round the expected round number
- */
-static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round)
-{
- unsigned work = parmap->work;
- /* wait for more work */
- while (work != round) {
- futex_wait(&parmap->work, work);
- work = parmap->work;
- }
-}
-#endif
-
-/**
- * \brief Starts the parmap: waits for all workers to be ready and returns.
- *
- * This function is called by the controller thread.
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap)
-{
- while (parmap->thread_counter < parmap->num_workers) {
- xbt_os_thread_yield();
- }
-}
-
-/**
- * \brief Ends the parmap: wakes the controller thread when all workers terminate.
- *
- * This function is called by all worker threads when they end.
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap)
-{
- __sync_add_and_fetch(&parmap->thread_counter, 1);
-}
-
-/**
- * \brief Wakes all workers and waits for them to finish the tasks.
- *
- * This function is called by the controller thread.
- *
- * \param parmap a parmap
- */
-static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap)
-{
- parmap->thread_counter = 1;
- __sync_add_and_fetch(&parmap->work, 1);
-}
-
-/**
- * \brief Waits for some work to process.
- *
- * This function is called by each worker thread (not including the controller) when it has no more work to do.
- *
- * \param parmap a parmap
- * \param round the expected round number
- */
-static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round)
-{
- /* wait for more work */
- while (parmap->work != round) {
- xbt_os_thread_yield();
- }
-}
