/* A thread pool (C++ version). */
-/* Copyright (c) 2004-2018 The SimGrid Team. All rights reserved. */
+/* Copyright (c) 2004-2019 The SimGrid Team. All rights reserved. */
/* 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 "src/internal_config.h" // HAVE_FUTEX_H
#include "src/kernel/context/Context.hpp"
-#include "xbt/xbt_os_thread.h"
#include <boost/optional.hpp>
#include <condition_variable>
#include <sys/syscall.h>
#endif
+#if HAVE_PTHREAD_NP_H
+#include <pthread_np.h>
+#endif
+
XBT_LOG_EXTERNAL_CATEGORY(xbt_parmap);
namespace simgrid {
void worker_wait(unsigned);
private:
- static void futex_wait(unsigned* uaddr, unsigned val);
- static void futex_wake(unsigned* uaddr, unsigned val);
+ static void futex_wait(std::atomic_uint* uaddr, unsigned val);
+ static void futex_wake(std::atomic_uint* uaddr, unsigned val);
};
#endif
void work();
Flag status; /**< is the parmap active or being destroyed? */
- unsigned work_round; /**< index of the current round */
- xbt_os_thread_t* workers; /**< worker thread handlers */
+ std::atomic_uint work_round; /**< index of the current round */
+ std::vector<std::thread*> workers; /**< worker thread handlers */
unsigned num_workers; /**< total number of worker threads including the controller */
Synchro* synchro; /**< synchronization object */
- unsigned thread_counter = 0; /**< number of workers that have done the work */
+ std::atomic_uint thread_counter{0}; /**< number of workers that have done the work */
void (*fun)(const T) = nullptr; /**< function to run in parallel on each element of data */
const std::vector<T>* data = nullptr; /**< parameters to pass to fun in parallel */
- std::atomic<unsigned> index; /**< index of the next element of data to pick */
+ std::atomic_uint index; /**< index of the next element of data to pick */
};
/**
/* Initialize the thread pool data structure */
this->status = PARMAP_WORK;
this->work_round = 0;
- this->workers = new xbt_os_thread_t[num_workers];
+ this->workers.resize(num_workers);
this->num_workers = num_workers;
this->synchro = new_synchro(mode);
- /* Create the pool of worker threads */
+ /* Create the pool of worker threads (the caller of apply() will be worker[0]) */
this->workers[0] = nullptr;
- unsigned int core_bind = 0;
+ XBT_ATTRIB_UNUSED unsigned int core_bind = 0;
+
for (unsigned i = 1; i < num_workers; i++) {
- ThreadData* data = new ThreadData(*this, i);
- this->workers[i] = xbt_os_thread_create(worker_main, data);
- xbt_os_thread_bind(this->workers[i], core_bind);
+ this->workers[i] = new std::thread(worker_main, new ThreadData(*this, i));
+
+ /* Bind the worker to a core if possible */
+#if HAVE_PTHREAD_SETAFFINITY
+#if HAVE_PTHREAD_NP_H /* FreeBSD ? */
+ cpuset_t cpuset;
+ size_t size = sizeof(cpuset_t);
+#else /* Linux ? */
+ cpu_set_t cpuset;
+ size_t size = sizeof(cpu_set_t);
+#endif
+ pthread_t pthread = this->workers[i]->native_handle();
+ CPU_ZERO(&cpuset);
+ CPU_SET(core_bind, &cpuset);
+ pthread_setaffinity_np(pthread, size, &cpuset);
if (core_bind != std::thread::hardware_concurrency() - 1)
core_bind++;
else
core_bind = 0;
+#endif
}
}
status = PARMAP_DESTROY;
synchro->master_signal();
- for (unsigned i = 1; i < num_workers; i++)
- xbt_os_thread_join(workers[i], nullptr);
-
- delete[] workers;
+ for (unsigned i = 1; i < num_workers; i++) {
+ workers[i]->join();
+ delete workers[i];
+ }
delete synchro;
}
return res;
}
-/**
- * @brief Main function of a worker thread.
- */
+/** @brief Main function of a worker thread */
template <typename T> void* Parmap<T>::worker_main(void* arg)
{
ThreadData* data = static_cast<ThreadData*>(arg);
/* Worker's main loop */
while (1) {
- round++;
+ round++; // New scheduling round
parmap.synchro->worker_wait(round);
if (parmap.status == PARMAP_DESTROY)
break;
}
#if HAVE_FUTEX_H
-template <typename T> inline void Parmap<T>::FutexSynchro::futex_wait(unsigned* uaddr, unsigned val)
+template <typename T> inline void Parmap<T>::FutexSynchro::futex_wait(std::atomic_uint* uaddr, unsigned val)
{
XBT_CVERB(xbt_parmap, "Waiting on futex %p", uaddr);
syscall(SYS_futex, uaddr, FUTEX_WAIT_PRIVATE, val, nullptr, nullptr, 0);
}
-template <typename T> inline void Parmap<T>::FutexSynchro::futex_wake(unsigned* uaddr, unsigned val)
+template <typename T> inline void Parmap<T>::FutexSynchro::futex_wake(std::atomic_uint* uaddr, unsigned val)
{
XBT_CVERB(xbt_parmap, "Waking futex %p", uaddr);
syscall(SYS_futex, uaddr, FUTEX_WAKE_PRIVATE, val, nullptr, nullptr, 0);
template <typename T> void Parmap<T>::FutexSynchro::master_signal()
{
- __atomic_store_n(&this->parmap.thread_counter, 1, __ATOMIC_SEQ_CST);
- __atomic_add_fetch(&this->parmap.work_round, 1, __ATOMIC_SEQ_CST);
+ this->parmap.thread_counter.store(1);
+ this->parmap.work_round.fetch_add(1);
/* wake all workers */
futex_wake(&this->parmap.work_round, std::numeric_limits<int>::max());
}
template <typename T> void Parmap<T>::FutexSynchro::master_wait()
{
- unsigned count = __atomic_load_n(&this->parmap.thread_counter, __ATOMIC_SEQ_CST);
+ unsigned count = this->parmap.thread_counter.load();
while (count < this->parmap.num_workers) {
/* wait for all workers to be ready */
futex_wait(&this->parmap.thread_counter, count);
- count = __atomic_load_n(&this->parmap.thread_counter, __ATOMIC_SEQ_CST);
+ count = this->parmap.thread_counter.load();
}
}
template <typename T> void Parmap<T>::FutexSynchro::worker_signal()
{
- unsigned count = __atomic_add_fetch(&this->parmap.thread_counter, 1, __ATOMIC_SEQ_CST);
+ unsigned count = this->parmap.thread_counter.fetch_add(1) + 1;
if (count == this->parmap.num_workers) {
/* all workers have finished, wake the controller */
futex_wake(&this->parmap.thread_counter, std::numeric_limits<int>::max());
template <typename T> void Parmap<T>::FutexSynchro::worker_wait(unsigned round)
{
- unsigned work_round = __atomic_load_n(&this->parmap.work_round, __ATOMIC_SEQ_CST);
+ unsigned work_round = this->parmap.work_round.load();
/* wait for more work */
while (work_round != round) {
futex_wait(&this->parmap.work_round, work_round);
- work_round = __atomic_load_n(&this->parmap.work_round, __ATOMIC_SEQ_CST);
+ work_round = this->parmap.work_round.load();
}
}
#endif
template <typename T> void Parmap<T>::BusyWaitSynchro::master_signal()
{
- __atomic_store_n(&this->parmap.thread_counter, 1, __ATOMIC_SEQ_CST);
- __atomic_add_fetch(&this->parmap.work_round, 1, __ATOMIC_SEQ_CST);
+ this->parmap.thread_counter.store(1);
+ this->parmap.work_round.fetch_add(1);
}
template <typename T> void Parmap<T>::BusyWaitSynchro::master_wait()
{
- while (__atomic_load_n(&this->parmap.thread_counter, __ATOMIC_SEQ_CST) < this->parmap.num_workers) {
+ while (this->parmap.thread_counter.load() < this->parmap.num_workers) {
std::this_thread::yield();
}
}
template <typename T> void Parmap<T>::BusyWaitSynchro::worker_signal()
{
- __atomic_add_fetch(&this->parmap.thread_counter, 1, __ATOMIC_SEQ_CST);
+ this->parmap.thread_counter.fetch_add(1);
}
template <typename T> void Parmap<T>::BusyWaitSynchro::worker_wait(unsigned round)
{
/* wait for more work */
- while (__atomic_load_n(&this->parmap.work_round, __ATOMIC_SEQ_CST) != round) {
+ while (this->parmap.work_round.load() != round) {
std::this_thread::yield();
}
}
