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// file : libbuild2/scheduler.ixx -*- C++ -*-
// license : MIT; see accompanying LICENSE file
namespace build2
{
inline size_t scheduler::
wait (size_t start_count, const atomic_count& task_count, work_queue wq)
{
// Note that task_count is a synchronization point.
//
size_t tc;
if ((tc = task_count.load (memory_order_acquire)) <= start_count)
return tc;
if (optional<size_t> r = wait_impl (start_count, task_count, wq))
return *r;
return suspend (start_count, task_count);
}
inline size_t scheduler::
wait (const atomic_count& task_count, work_queue wq)
{
return wait (0, task_count, wq);
}
template <typename L>
inline size_t scheduler::
wait (size_t start_count,
const atomic_count& task_count,
L& lock,
work_queue wq)
{
// Note that task_count is a synchronization point.
//
size_t tc;
if ((tc = task_count.load (memory_order_acquire)) <= start_count)
return tc;
if (optional<size_t> r = wait_impl (start_count, task_count, wq))
return *r;
lock.unlock ();
return suspend (start_count, task_count);
}
inline void scheduler::
deactivate (bool external)
{
if (max_active_ != 1) // Serial execution.
deactivate_impl (external, lock (mutex_));
}
inline void scheduler::
activate (bool external)
{
if (max_active_ != 1) // Serial execution.
activate_impl (external, false /* collision */);
}
inline scheduler::queue_mark::
queue_mark (scheduler& s)
: tq_ (s.queue ())
{
if (tq_ != nullptr)
{
lock ql (tq_->mutex);
if (tq_->mark != s.task_queue_depth_)
{
om_ = tq_->mark;
tq_->mark = s.task_queue_depth_;
}
else
tq_ = nullptr;
}
}
inline scheduler::queue_mark::
~queue_mark ()
{
if (tq_ != nullptr)
{
lock ql (tq_->mutex);
tq_->mark = tq_->size == 0 ? tq_->tail : om_;
}
}
}
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