static void DVDThread()
{
Common::SetCurrentThreadName("DVD thread");
while (true)
{
s_request_queue_expanded.Wait();
if (s_dvd_thread_exiting.IsSet())
return;
ReadRequest request;
while (s_request_queue.Pop(request))
{
FileMonitor::Log(*s_disc, request.partition, request.dvd_offset);
std::vector<u8> buffer(request.length);
if (!s_disc->Read(request.dvd_offset, request.length, buffer.data(), request.partition))
buffer.resize(0);
request.realtime_done_us = Common::Timer::GetTimeUs();
s_result_queue.Push(ReadResult(std::move(request), std::move(buffer)));
s_result_queue_expanded.Set();
if (s_dvd_thread_exiting.IsSet())
return;
}
}
}
static void FinishRead(u64 id, s64 cycles_late)
{
// We can't simply pop s_result_queue and always get the ReadResult
// we want, because the DVD thread may add ReadResults to the queue
// in a different order than we want to get them. What we do instead
// is to pop the queue until we find the ReadResult we want (the one
// whose ID matches userdata), which means we may end up popping
// ReadResults that we don't want. We can't add those unwanted results
// back to the queue, because the queue can only have one writer.
// Instead, we add them to a map that only is used by the CPU thread.
// When this function is called again later, it will check the map for
// the wanted ReadResult before it starts searching through the queue.
ReadResult result;
auto it = s_result_map.find(id);
if (it != s_result_map.end())
{
result = std::move(it->second);
s_result_map.erase(it);
}
else
{
while (true)
{
while (!s_result_queue.Pop(result))
s_result_queue_expanded.Wait();
if (result.first.id == id)
break;
else
s_result_map.emplace(result.first.id, std::move(result));
}
}
// We have now obtained the right ReadResult.
const ReadRequest& request = result.first;
const std::vector<u8>& buffer = result.second;
DEBUG_LOG(DVDINTERFACE, "Disc has been read. Real time: %" PRIu64 " us. "
"Real time including delay: %" PRIu64 " us. "
"Emulated time including delay: %" PRIu64 " us.",
request.realtime_done_us - request.realtime_started_us,
Common::Timer::GetTimeUs() - request.realtime_started_us,
(CoreTiming::GetTicks() - request.time_started_ticks) /
(SystemTimers::GetTicksPerSecond() / 1000000));
if (buffer.size() != request.length)
{
PanicAlertT("The disc could not be read (at 0x%" PRIx64 " - 0x%" PRIx64 ").",
request.dvd_offset, request.dvd_offset + request.length);
}
else
{
if (request.copy_to_ram)
Memory::CopyToEmu(request.output_address, buffer.data(), request.length);
}
// Notify the emulated software that the command has been executed
DVDInterface::FinishExecutingCommand(request.reply_type, DVDInterface::INT_TCINT, cycles_late,
buffer);
}
void MoveEvents()
{
for (Event ev; s_ts_queue.Pop(ev);)
{
ev.fifo_order = s_event_fifo_id++;
s_event_queue.emplace_back(std::move(ev));
std::push_heap(s_event_queue.begin(), s_event_queue.end(), std::greater<Event>());
}
}
void DoState(PointerWrap& p)
{
// By waiting for the DVD thread to be done working, we ensure
// that s_request_queue will be empty and that the DVD thread
// won't be touching anything while this function runs.
WaitUntilIdle();
// Move all results from s_result_queue to s_result_map because
// PointerWrap::Do supports std::map but not Common::SPSCQueue.
// This won't affect the behavior of FinishRead.
ReadResult result;
while (s_result_queue.Pop(result))
s_result_map.emplace(result.first.id, std::move(result));
// Both queues are now empty, so we don't need to savestate them.
p.Do(s_result_map);
p.Do(s_next_id);
// s_disc isn't savestated (because it points to files on the
// local system). Instead, we check that the status of the disc
// is the same as when the savestate was made. This won't catch
// cases of having the wrong disc inserted, though.
// TODO: Check the game ID, disc number, revision?
bool had_disc = HasDisc();
p.Do(had_disc);
if (had_disc != HasDisc())
{
if (had_disc)
PanicAlertT("An inserted disc was expected but not found.");
else
s_disc.reset();
}
// TODO: Savestates can be smaller if the buffers of results aren't saved,
// but instead get re-read from the disc when loading the savestate.
// TODO: It would be possible to create a savestate faster by stopping
// the DVD thread regardless of whether there are pending requests.
// After loading a savestate, the debug log in FinishRead will report
// screwed up times for requests that were submitted before the savestate
// was made. Handling that properly may be more effort than it's worth.
}