Method schedule

3rdparty/asyncplusplus/src/threadpool_scheduler.cpp:402–440

Schedule a task on the thread pool

// Schedule a task on the thread pool
void threadpool_scheduler::schedule(task_run_handle t)
{
	detail::threadpool_data_wrapper wrapper = detail::get_threadpool_data_wrapper();
	
	// Check if we are in the thread pool
	if (wrapper.owning_threadpool == impl.get()) {
		// Push the task onto our task queue
		impl->thread_data[wrapper.thread_id].queue.push(std::move(t));

		// If there are no sleeping threads, just return. We check outside the
		// lock to avoid locking overhead in the fast path.
		if (impl->num_waiters.load(std::memory_order_relaxed) == 0)
			return;

		// Get a thread to wake up from the list
		std::lock_guard<std::mutex> locked(impl->lock);

		// Check again if there are waiters
		size_t num_waiters_val = impl->num_waiters.load(std::memory_order_relaxed);
		if (num_waiters_val == 0)
			return;

		// Pop a thread from the list and wake it up
		impl->waiters[num_waiters_val - 1]->signal(detail::wait_type::task_available);
		impl->num_waiters.store(num_waiters_val - 1, std::memory_order_relaxed);
	} else {
		std::lock_guard<std::mutex> locked(impl->lock);

		// Push task onto the public queue
		impl->public_queue.push(std::move(t));

		// Wake up a sleeping thread
		size_t num_waiters_val = impl->num_waiters.load(std::memory_order_relaxed);
		if (num_waiters_val == 0)
			return;
		impl->waiters[num_waiters_val - 1]->signal(detail::wait_type::task_available);
		impl->num_waiters.store(num_waiters_val - 1, std::memory_order_relaxed);
	}
}

} // namespace async