Files
rippled/include/xrpl/core/Coro.ipp
2026-03-27 18:52:18 +00:00

133 lines
3.3 KiB
C++

#pragma once
namespace xrpl {
template <class F>
JobQueue::Coro::Coro(Coro_create_t, JobQueue& jq, JobType type, std::string const& name, F&& f)
: jq_(jq)
, type_(type)
, name_(name)
, running_(false)
, coro_(
// Stack size of 1MB wasn't sufficient for deep calls. ASAN tests flagged the issue. Hence
// increasing the size to 1.5MB.
boost::context::protected_fixedsize_stack(1536 * 1024),
[this, fn = std::forward<F>(f)](
boost::coroutines2::asymmetric_coroutine<void>::push_type& do_yield) {
yield_ = &do_yield;
yield();
fn(shared_from_this());
#ifndef NDEBUG
finished_ = true;
#endif
})
{
}
inline JobQueue::Coro::~Coro()
{
#ifndef NDEBUG
XRPL_ASSERT(finished_, "xrpl::JobQueue::Coro::~Coro : is finished");
#endif
}
inline void
JobQueue::Coro::yield() const
{
{
std::lock_guard lock(jq_.m_mutex);
++jq_.nSuspend_;
}
(*yield_)();
}
inline bool
JobQueue::Coro::post()
{
{
std::lock_guard lk(mutex_run_);
running_ = true;
}
// sp keeps 'this' alive
if (jq_.addJob(type_, name_, [this, sp = shared_from_this()]() { resume(); }))
{
return true;
}
// The coroutine will not run. Clean up running_.
std::lock_guard lk(mutex_run_);
running_ = false;
cv_.notify_all();
return false;
}
inline void
JobQueue::Coro::resume()
{
{
std::lock_guard lk(mutex_run_);
running_ = true;
}
{
std::lock_guard lk(jq_.m_mutex);
--jq_.nSuspend_;
}
auto saved = detail::getLocalValues().release();
detail::getLocalValues().reset(&lvs_);
std::lock_guard lock(mutex_);
// A late resume() can arrive after the coroutine has already completed.
// This is an expected (if rare) outcome of the race condition documented
// in JobQueue.h:354-377 where post() schedules a resume job before the
// coroutine yields — the mutex serializes access, but by the time this
// resume() acquires the lock the coroutine may have already run to
// completion. Calling operator() on a completed boost::coroutine2 is
// undefined behavior, so we must check and skip invoking the coroutine
// body if it has already completed.
if (coro_)
{
coro_();
}
detail::getLocalValues().release();
detail::getLocalValues().reset(saved);
std::lock_guard lk(mutex_run_);
running_ = false;
cv_.notify_all();
}
inline bool
JobQueue::Coro::runnable() const
{
return static_cast<bool>(coro_);
}
inline void
JobQueue::Coro::expectEarlyExit()
{
#ifndef NDEBUG
if (!finished_)
#endif
{
// expectEarlyExit() must only ever be called from outside the
// Coro's stack. It you're inside the stack you can simply return
// and be done.
//
// That said, since we're outside the Coro's stack, we need to
// decrement the nSuspend that the Coro's call to yield caused.
std::lock_guard lock(jq_.m_mutex);
--jq_.nSuspend_;
#ifndef NDEBUG
finished_ = true;
#endif
}
}
inline void
JobQueue::Coro::join()
{
std::unique_lock<std::mutex> lk(mutex_run_);
cv_.wait(lk, [this]() { return running_ == false; });
}
} // namespace xrpl