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SystemTimers: export performance index from the throttler callback
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@delroth
delroth committed Oct 27, 2018
1 parent eadb4a6 commit 64e04eb
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Showing 2 changed files with 124 additions and 63 deletions.
176 changes: 114 additions & 62 deletions Source/Core/Core/HW/SystemTimers.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -45,6 +45,7 @@ IPC_HLE_PERIOD: For the Wii Remote this is the call schedule:

#include "Core/HW/SystemTimers.h"

#include <cfloat>
#include <cmath>
#include <cstdlib>

Expand All @@ -68,51 +69,58 @@ IPC_HLE_PERIOD: For the Wii Remote this is the call schedule:

namespace SystemTimers
{
static CoreTiming::EventType* et_Dec;
static CoreTiming::EventType* et_VI;
static CoreTiming::EventType* et_AudioDMA;
static CoreTiming::EventType* et_DSP;
static CoreTiming::EventType* et_IPC_HLE;
namespace
{
CoreTiming::EventType* et_Dec;
CoreTiming::EventType* et_VI;
CoreTiming::EventType* et_AudioDMA;
CoreTiming::EventType* et_DSP;
CoreTiming::EventType* et_IPC_HLE;
// PatchEngine updates every 1/60th of a second by default
static CoreTiming::EventType* et_PatchEngine;
static CoreTiming::EventType* et_Throttle;
CoreTiming::EventType* et_PatchEngine;
CoreTiming::EventType* et_Throttle;

static u32 s_cpu_core_clock = 486000000u; // 486 mhz (its not 485, stop bugging me!)
u32 s_cpu_core_clock = 486000000u; // 486 mhz (its not 485, stop bugging me!)

// These two are badly educated guesses.
// Feel free to experiment. Set them in Init below.

// This is a fixed value, don't change it
static int s_audio_dma_period;
int s_audio_dma_period;
// This is completely arbitrary. If we find that we need lower latency,
// we can just increase this number.
static int s_ipc_hle_period;
int s_ipc_hle_period;

// Custom RTC
static s64 s_localtime_rtc_offset = 0;
s64 s_localtime_rtc_offset = 0;

u32 GetTicksPerSecond()
{
return s_cpu_core_clock;
}
// For each emulated milliseconds, what was the real time timestamp (excluding sleep time). This is
// a "special" ring buffer where we only need to read the first and last value.
std::array<u64, 1000> s_emu_to_real_time_ring_buffer;
size_t s_emu_to_real_time_index;
std::mutex s_emu_to_real_time_mutex;

// How much time was spent sleeping since the emulator started. Note: this does not need to be reset
// at initialization (or ever), since only the "derivative" of that value really matters.
u64 s_time_spent_sleeping;

// DSP/CPU timeslicing.
static void DSPCallback(u64 userdata, s64 cyclesLate)
void DSPCallback(u64 userdata, s64 cyclesLate)
{
// splits up the cycle budget in case lle is used
// for hle, just gives all of the slice to hle
DSP::UpdateDSPSlice(static_cast<int>(DSP::GetDSPEmulator()->DSP_UpdateRate() - cyclesLate));
CoreTiming::ScheduleEvent(DSP::GetDSPEmulator()->DSP_UpdateRate() - cyclesLate, et_DSP);
}

static void AudioDMACallback(u64 userdata, s64 cyclesLate)
void AudioDMACallback(u64 userdata, s64 cyclesLate)
{
int period = s_cpu_core_clock / (AudioInterface::GetAIDSampleRate() * 4 / 32);
DSP::UpdateAudioDMA(); // Push audio to speakers.
CoreTiming::ScheduleEvent(period - cyclesLate, et_AudioDMA);
}

static void IPC_HLE_UpdateCallback(u64 userdata, s64 cyclesLate)
void IPC_HLE_UpdateCallback(u64 userdata, s64 cyclesLate)
{
if (SConfig::GetInstance().bWii)
{
Expand All @@ -121,56 +129,19 @@ static void IPC_HLE_UpdateCallback(u64 userdata, s64 cyclesLate)
}
}

static void VICallback(u64 userdata, s64 cyclesLate)
void VICallback(u64 userdata, s64 cyclesLate)
{
VideoInterface::Update(CoreTiming::GetTicks() - cyclesLate);
CoreTiming::ScheduleEvent(VideoInterface::GetTicksPerHalfLine() - cyclesLate, et_VI);
}

static void DecrementerCallback(u64 userdata, s64 cyclesLate)
void DecrementerCallback(u64 userdata, s64 cyclesLate)
{
PowerPC::ppcState.spr[SPR_DEC] = 0xFFFFFFFF;
PowerPC::ppcState.Exceptions |= EXCEPTION_DECREMENTER;
}

void DecrementerSet()
{
u32 decValue = PowerPC::ppcState.spr[SPR_DEC];

CoreTiming::RemoveEvent(et_Dec);
if ((decValue & 0x80000000) == 0)
{
CoreTiming::SetFakeDecStartTicks(CoreTiming::GetTicks());
CoreTiming::SetFakeDecStartValue(decValue);

CoreTiming::ScheduleEvent(decValue * TIMER_RATIO, et_Dec);
}
}

u32 GetFakeDecrementer()
{
return (CoreTiming::GetFakeDecStartValue() -
(u32)((CoreTiming::GetTicks() - CoreTiming::GetFakeDecStartTicks()) / TIMER_RATIO));
}

void TimeBaseSet()
{
CoreTiming::SetFakeTBStartTicks(CoreTiming::GetTicks());
CoreTiming::SetFakeTBStartValue(PowerPC::ReadFullTimeBaseValue());
}

u64 GetFakeTimeBase()
{
return CoreTiming::GetFakeTBStartValue() +
((CoreTiming::GetTicks() - CoreTiming::GetFakeTBStartTicks()) / TIMER_RATIO);
}

s64 GetLocalTimeRTCOffset()
{
return s_localtime_rtc_offset;
}

static void PatchEngineCallback(u64 userdata, s64 cycles_late)
void PatchEngineCallback(u64 userdata, s64 cycles_late)
{
// We have 2 periods, a 1000 cycle error period and the VI period.
// We have to carefully combine these together so that we stay on the VI period without drifting.
Expand All @@ -195,7 +166,7 @@ static void PatchEngineCallback(u64 userdata, s64 cycles_late)
CoreTiming::ScheduleEvent(next_schedule, et_PatchEngine, cycles_pruned);
}

static void ThrottleCallback(u64 last_time, s64 cyclesLate)
void ThrottleCallback(u64 last_time, s64 cyclesLate)
{
// Allow the GPU thread to sleep. Setting this flag here limits the wakeups to 1 kHz.
Fifo::GpuMaySleep();
Expand All @@ -206,22 +177,101 @@ static void ThrottleCallback(u64 last_time, s64 cyclesLate)
const SConfig& config = SConfig::GetInstance();
bool frame_limiter = config.m_EmulationSpeed > 0.0f && !Core::GetIsThrottlerTempDisabled();
u32 next_event = GetTicksPerSecond() / 1000;

{
std::lock_guard<std::mutex> lk(s_emu_to_real_time_mutex);
s_emu_to_real_time_ring_buffer[s_emu_to_real_time_index] = time - s_time_spent_sleeping;
s_emu_to_real_time_index =
(s_emu_to_real_time_index + 1) % s_emu_to_real_time_ring_buffer.size();
}

if (frame_limiter)
{
if (config.m_EmulationSpeed != 1.0f)
next_event = u32(next_event * config.m_EmulationSpeed);
const s64 max_fallback = config.iTimingVariance * 1000;
if (abs(diff) > max_fallback)
{
DEBUG_LOG(COMMON, "system too %s, %d ms skipped", diff < 0 ? "slow" : "fast",
DEBUG_LOG(COMMON, "system too %s, %ld ms skipped", diff < 0 ? "slow" : "fast",
abs(diff) - max_fallback);
last_time = time - max_fallback;
}
else if ((diff / 1000) > 0)
else if (diff > 1000)
{
Common::SleepCurrentThread(diff / 1000);
s_time_spent_sleeping += Common::Timer::GetTimeUs() - time;
}
}
CoreTiming::ScheduleEvent(next_event - cyclesLate, et_Throttle, last_time + 1000);
}
} // namespace

u32 GetTicksPerSecond()
{
return s_cpu_core_clock;
}

void DecrementerSet()
{
u32 decValue = PowerPC::ppcState.spr[SPR_DEC];

CoreTiming::RemoveEvent(et_Dec);
if ((decValue & 0x80000000) == 0)
{
CoreTiming::SetFakeDecStartTicks(CoreTiming::GetTicks());
CoreTiming::SetFakeDecStartValue(decValue);

CoreTiming::ScheduleEvent(decValue * TIMER_RATIO, et_Dec);
}
}

u32 GetFakeDecrementer()
{
return (CoreTiming::GetFakeDecStartValue() -
(u32)((CoreTiming::GetTicks() - CoreTiming::GetFakeDecStartTicks()) / TIMER_RATIO));
}

void TimeBaseSet()
{
CoreTiming::SetFakeTBStartTicks(CoreTiming::GetTicks());
CoreTiming::SetFakeTBStartValue(PowerPC::ReadFullTimeBaseValue());
}

u64 GetFakeTimeBase()
{
return CoreTiming::GetFakeTBStartValue() +
((CoreTiming::GetTicks() - CoreTiming::GetFakeTBStartTicks()) / TIMER_RATIO);
}

s64 GetLocalTimeRTCOffset()
{
return s_localtime_rtc_offset;
}

double GetEstimatedEmulationPerformance()
{
u64 ts_now, ts_before; // In microseconds
{
std::lock_guard<std::mutex> lk(s_emu_to_real_time_mutex);
size_t index_now = s_emu_to_real_time_index == 0 ? s_emu_to_real_time_ring_buffer.size() :
s_emu_to_real_time_index - 1;
size_t index_before = s_emu_to_real_time_index;

ts_now = s_emu_to_real_time_ring_buffer[index_now];
ts_before = s_emu_to_real_time_ring_buffer[index_before];
}

if (ts_before == 0)
{
// Not enough data yet to estimate. We could technically provide an estimate based on a shorter
// time horizon, but it's not really worth it.
return 1.0;
}

u64 delta_us = ts_now - ts_before;
double emulated_us = s_emu_to_real_time_ring_buffer.size() * 1000.0; // For each emulated ms.
return delta_us == 0 ? DBL_MAX : emulated_us / delta_us;
}

// split from Init to break a circular dependency between VideoInterface::Init and
// SystemTimers::Init
Expand Down Expand Up @@ -288,6 +338,8 @@ void Init()

if (SConfig::GetInstance().bWii)
CoreTiming::ScheduleEvent(s_ipc_hle_period, et_IPC_HLE);

s_emu_to_real_time_ring_buffer.fill(0);
}

void Shutdown()
Expand All @@ -296,4 +348,4 @@ void Shutdown()
s_localtime_rtc_offset = 0;
}

} // namespace
} // namespace SystemTimers
11 changes: 10 additions & 1 deletion Source/Core/Core/HW/SystemTimers.h
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Original file line number Diff line number Diff line change
Expand Up @@ -53,4 +53,13 @@ void TimeBaseSet();
u64 GetFakeTimeBase();
// Custom RTC
s64 GetLocalTimeRTCOffset();
}

// Returns an estimate of how fast/slow the emulation is running (excluding throttling induced sleep
// time). The estimate is computed over the last 1s of emulated time. Example values:
//
// - 0.5: the emulator is running at 50% speed (falling behind).
// - 1.0: the emulator is running at 100% speed.
// - 2.0: the emulator is running at 200% speed (or 100% speed but sleeping half of the time).
double GetEstimatedEmulationPerformance();

} // namespace SystemTimers

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