-inline void UContext::swap(UContext* from, UContext* to)
-{
- ASAN_ONLY(void* fake_stack = nullptr);
- ASAN_ONLY(to->asan_ctx_ = from);
- ASAN_START_SWITCH(from->asan_stop_ ? nullptr : &fake_stack, to->asan_stack_, to->asan_stack_size_);
- swapcontext(&from->uc_, &to->uc_);
- ASAN_FINISH_SWITCH(fake_stack, &from->asan_ctx_->asan_stack_, &from->asan_ctx_->asan_stack_size_);
-}
-
-void UContext::stop()
-{
- Context::stop();
- throw StopRequest();
-}
-
-// SerialUContext
-
-unsigned long SerialUContext::process_index_; /* index of the next process to run in the list of runnable processes */
-
-void SerialUContext::suspend()
-{
- /* determine the next context */
- SerialUContext* next_context;
- unsigned long int i = process_index_;
- process_index_++;
-
- if (i < simix_global->process_to_run.size()) {
- /* execute the next process */
- XBT_DEBUG("Run next process");
- next_context = static_cast<SerialUContext*>(simix_global->process_to_run[i]->context_);
- } else {
- /* all processes were run, return to maestro */
- XBT_DEBUG("No more process to run");
- next_context = static_cast<SerialUContext*>(UContext::get_maestro());
- }
- SIMIX_context_set_current(next_context);
- UContext::swap(this, next_context);
-}
-
-void SerialUContext::resume()
-{
- SIMIX_context_set_current(this);
- UContext::swap(UContext::get_maestro(), this);
-}
-
-void SerialUContext::run_all()
-{
- if (simix_global->process_to_run.empty())
- return;
- smx_actor_t first_process = simix_global->process_to_run.front();
- process_index_ = 1;
- static_cast<SerialUContext*>(first_process->context_)->resume();
-}
-
-// ParallelUContext
-
-#if HAVE_THREAD_CONTEXTS
-
-simgrid::xbt::Parmap<smx_actor_t>* ParallelUContext::parmap_;
-std::atomic<uintptr_t> ParallelUContext::threads_working_; /* number of threads that have started their work */
-thread_local uintptr_t ParallelUContext::worker_id_; /* thread-specific storage for the thread id */
-std::vector<ParallelUContext*> ParallelUContext::workers_context_; /* space to save the worker's context
- * in each thread */
-
-void ParallelUContext::initialize()
-{
- parmap_ = nullptr;
- workers_context_.clear();
- workers_context_.resize(SIMIX_context_get_nthreads(), nullptr);
-}
-
-void ParallelUContext::finalize()
-{
- delete parmap_;
- parmap_ = nullptr;
- workers_context_.clear();
-}
-
-void ParallelUContext::run_all()
-{
- threads_working_ = 0;
- // Parmap_apply ensures that every working thread get an index in the process_to_run array (through an atomic
- // fetch_and_add), and runs the ParallelUContext::resume function on that index
-
- // We lazily create the parmap because the parmap creates context with simix_global->context_factory (which might not
- // be initialized when bootstrapping):
- if (parmap_ == nullptr)
- parmap_ = new simgrid::xbt::Parmap<smx_actor_t>(SIMIX_context_get_nthreads(), SIMIX_context_get_parallel_mode());
- parmap_->apply(
- [](smx_actor_t process) {
- ParallelUContext* context = static_cast<ParallelUContext*>(process->context_);
- context->resume();
- },
- simix_global->process_to_run);
-}
-
-/** Yield
- *
- * This function is called when a simulated process wants to yield back to the maestro in a blocking simcall. This
- * naturally occurs within SIMIX_context_suspend(self->context), called from SIMIX_process_yield() Actually, it does not
- * really yield back to maestro, but into the next process that must be executed. If no one is to be executed, then it
- * yields to the initial soul that was in this working thread (that was saved in resume_parallel).
- */
-void ParallelUContext::suspend()
-{
- /* determine the next context */
- // Get the next soul to embody now:
- boost::optional<smx_actor_t> next_work = parmap_->next();
- ParallelUContext* next_context;
- if (next_work) {
- // There is a next soul to embody (ie, a next process to resume)
- XBT_DEBUG("Run next process");
- next_context = static_cast<ParallelUContext*>(next_work.get()->context_);
- } else {
- // All processes were run, go to the barrier
- XBT_DEBUG("No more processes to run");
- // worker_id_ is the identity of my body, stored in thread_local when starting the scheduling round
- // Deduce the initial soul of that body
- next_context = workers_context_[worker_id_];
- // When given that soul, the body will wait for the next scheduling round
- }
-
- SIMIX_context_set_current(next_context);
- // Get the next soul to run, either simulated or initial minion's one:
- UContext::swap(this, next_context);
-}
-
-/** Run one particular simulated process on the current thread. */
-void ParallelUContext::resume()
-{
- // What is my containing body? Store its number in os-thread-specific area :
- worker_id_ = threads_working_.fetch_add(1, std::memory_order_relaxed);
- // Get my current soul:
- ParallelUContext* worker_context = static_cast<ParallelUContext*>(SIMIX_context_self());
- // Write down that this soul is hosted in that body (for now)
- workers_context_[worker_id_] = worker_context;
- // Write in simix that I switched my soul
- SIMIX_context_set_current(this);
- // Actually do that using the relevant library call:
- UContext::swap(worker_context, this);
- // No body runs that soul anymore at this point. Instead the current body took the soul of simulated process The
- // simulated process wakes back after the call to "SIMIX_context_suspend(self->context);" within
- // smx_process.c::SIMIX_process_yield()
-
- // From now on, the simulated processes will change their soul with the next soul to execute (in suspend_parallel,
- // below). When nobody is to be executed in this scheduling round, the last simulated process will take back the
- // initial soul of the current working thread
-}
-
-#endif