From 555866f8dcb98897688d5d7b0e6c6cca55ac069f Mon Sep 17 00:00:00 2001 From: Fernando Sahmkow Date: Mon, 9 Sep 2019 21:37:29 -0400 Subject: Core Timing: Rework Core Timing to run all cores evenly. --- src/core/arm/dynarmic/arm_dynarmic.cpp | 2 +- src/core/arm/unicorn/arm_unicorn.cpp | 2 +- src/core/core_cpu.cpp | 14 ++------ src/core/core_timing.cpp | 66 +++++++++++++++++++++++++--------- src/core/core_timing.h | 24 +++++++++++-- src/core/cpu_core_manager.cpp | 19 ++++++---- 6 files changed, 89 insertions(+), 38 deletions(-) diff --git a/src/core/arm/dynarmic/arm_dynarmic.cpp b/src/core/arm/dynarmic/arm_dynarmic.cpp index f1506b372..4d2e99ed0 100644 --- a/src/core/arm/dynarmic/arm_dynarmic.cpp +++ b/src/core/arm/dynarmic/arm_dynarmic.cpp @@ -116,7 +116,7 @@ public: num_interpreted_instructions = 0; } u64 GetTicksRemaining() override { - return std::max(parent.system.CoreTiming().GetDowncount(), 0); + return std::max(parent.system.CoreTiming().GetDowncount(), 0LL); } u64 GetCNTPCT() override { return Timing::CpuCyclesToClockCycles(parent.system.CoreTiming().GetTicks()); diff --git a/src/core/arm/unicorn/arm_unicorn.cpp b/src/core/arm/unicorn/arm_unicorn.cpp index 97d5c2a8a..3f91b06d4 100644 --- a/src/core/arm/unicorn/arm_unicorn.cpp +++ b/src/core/arm/unicorn/arm_unicorn.cpp @@ -156,7 +156,7 @@ void ARM_Unicorn::Run() { if (GDBStub::IsServerEnabled()) { ExecuteInstructions(std::max(4000000, 0)); } else { - ExecuteInstructions(std::max(system.CoreTiming().GetDowncount(), 0)); + ExecuteInstructions(std::max(system.CoreTiming().GetDowncount(), 0LL)); } } diff --git a/src/core/core_cpu.cpp b/src/core/core_cpu.cpp index 21c410e34..6bd9639c6 100644 --- a/src/core/core_cpu.cpp +++ b/src/core/core_cpu.cpp @@ -85,24 +85,16 @@ void Cpu::RunLoop(bool tight_loop) { // instead advance to the next event and try to yield to the next thread if (Kernel::GetCurrentThread() == nullptr) { LOG_TRACE(Core, "Core-{} idling", core_index); - - if (IsMainCore()) { - // TODO(Subv): Only let CoreTiming idle if all 4 cores are idling. - core_timing.Idle(); - core_timing.Advance(); - } - + core_timing.Idle(); + core_timing.Advance(); PrepareReschedule(); } else { - if (IsMainCore()) { - core_timing.Advance(); - } - if (tight_loop) { arm_interface->Run(); } else { arm_interface->Step(); } + core_timing.Advance(); } Reschedule(); diff --git a/src/core/core_timing.cpp b/src/core/core_timing.cpp index a58f7b131..6da2dcfb4 100644 --- a/src/core/core_timing.cpp +++ b/src/core/core_timing.cpp @@ -15,7 +15,7 @@ namespace Core::Timing { -constexpr int MAX_SLICE_LENGTH = 20000; +constexpr int MAX_SLICE_LENGTH = 10000; struct CoreTiming::Event { s64 time; @@ -38,10 +38,14 @@ CoreTiming::CoreTiming() = default; CoreTiming::~CoreTiming() = default; void CoreTiming::Initialize() { - downcount = MAX_SLICE_LENGTH; + for (std::size_t core = 0; core < num_cpu_cores; core++) { + downcounts[core] = MAX_SLICE_LENGTH; + time_slice[core] = MAX_SLICE_LENGTH; + } slice_length = MAX_SLICE_LENGTH; global_timer = 0; idled_cycles = 0; + current_context = 0; // The time between CoreTiming being initialized and the first call to Advance() is considered // the slice boundary between slice -1 and slice 0. Dispatcher loops must call Advance() before @@ -110,7 +114,7 @@ void CoreTiming::UnscheduleEvent(const EventType* event_type, u64 userdata) { u64 CoreTiming::GetTicks() const { u64 ticks = static_cast(global_timer); if (!is_global_timer_sane) { - ticks += slice_length - downcount; + ticks += time_slice[current_context] - downcounts[current_context]; } return ticks; } @@ -120,7 +124,7 @@ u64 CoreTiming::GetIdleTicks() const { } void CoreTiming::AddTicks(u64 ticks) { - downcount -= static_cast(ticks); + downcounts[current_context] -= static_cast(ticks); } void CoreTiming::ClearPendingEvents() { @@ -141,22 +145,36 @@ void CoreTiming::RemoveEvent(const EventType* event_type) { void CoreTiming::ForceExceptionCheck(s64 cycles) { cycles = std::max(0, cycles); - if (downcount <= cycles) { + if (downcounts[current_context] <= cycles) { return; } // downcount is always (much) smaller than MAX_INT so we can safely cast cycles to an int // here. Account for cycles already executed by adjusting the g.slice_length - slice_length -= downcount - static_cast(cycles); - downcount = static_cast(cycles); + slice_length -= downcounts[current_context] - static_cast(cycles); + downcounts[current_context] = static_cast(cycles); +} + +std::optional CoreTiming::NextAvailableCore(const s64 needed_ticks) const { + const u64 original_context = current_context; + u64 next_context = (original_context + 1) % num_cpu_cores; + while (next_context != original_context) { + if (time_slice[next_context] >= needed_ticks) { + return {next_context}; + } else if (time_slice[next_context] >= 0) { + return {}; + } + next_context = (next_context + 1) % num_cpu_cores; + } + return {}; } void CoreTiming::Advance() { std::unique_lock guard(inner_mutex); - const int cycles_executed = slice_length - downcount; + const int cycles_executed = time_slice[current_context] - downcounts[current_context]; + time_slice[current_context] = std::max(0, downcounts[current_context]); global_timer += cycles_executed; - slice_length = MAX_SLICE_LENGTH; is_global_timer_sane = true; @@ -173,24 +191,40 @@ void CoreTiming::Advance() { // Still events left (scheduled in the future) if (!event_queue.empty()) { - slice_length = static_cast( - std::min(event_queue.front().time - global_timer, MAX_SLICE_LENGTH)); + s64 needed_ticks = std::min(event_queue.front().time - global_timer, MAX_SLICE_LENGTH); + const auto next_core = NextAvailableCore(needed_ticks); + if (next_core) { + downcounts[*next_core] = needed_ticks; + } } - downcount = slice_length; + downcounts[current_context] = time_slice[current_context]; +} + +void CoreTiming::ResetRun() { + for (std::size_t core = 0; core < num_cpu_cores; core++) { + downcounts[core] = MAX_SLICE_LENGTH; + time_slice[core] = MAX_SLICE_LENGTH; + } + current_context = 0; + // Still events left (scheduled in the future) + if (!event_queue.empty()) { + s64 needed_ticks = std::min(event_queue.front().time - global_timer, MAX_SLICE_LENGTH); + downcounts[current_context] = needed_ticks; + } } void CoreTiming::Idle() { - idled_cycles += downcount; - downcount = 0; + idled_cycles += downcounts[current_context]; + downcounts[current_context] = 0; } std::chrono::microseconds CoreTiming::GetGlobalTimeUs() const { return std::chrono::microseconds{GetTicks() * 1000000 / BASE_CLOCK_RATE}; } -int CoreTiming::GetDowncount() const { - return downcount; +s64 CoreTiming::GetDowncount() const { + return downcounts[current_context]; } } // namespace Core::Timing diff --git a/src/core/core_timing.h b/src/core/core_timing.h index 161c7007d..ec0a6d2c0 100644 --- a/src/core/core_timing.h +++ b/src/core/core_timing.h @@ -7,6 +7,7 @@ #include #include #include +#include #include #include #include @@ -104,7 +105,19 @@ public: std::chrono::microseconds GetGlobalTimeUs() const; - int GetDowncount() const; + void ResetRun(); + + s64 GetDowncount() const; + + void SwitchContext(u64 new_context) { + current_context = new_context; + } + + bool CurrentContextCanRun() const { + return time_slice[current_context] > 0; + } + + std::optional NextAvailableCore(const s64 needed_ticks) const; private: struct Event; @@ -112,10 +125,15 @@ private: /// Clear all pending events. This should ONLY be done on exit. void ClearPendingEvents(); + static constexpr u64 num_cpu_cores = 4; + s64 global_timer = 0; s64 idled_cycles = 0; - int slice_length = 0; - int downcount = 0; + s64 slice_length = 0; + std::array downcounts{}; + // Slice of time assigned to each core per run. + std::array time_slice{}; + u64 current_context = 0; // Are we in a function that has been called from Advance() // If events are scheduled from a function that gets called from Advance(), diff --git a/src/core/cpu_core_manager.cpp b/src/core/cpu_core_manager.cpp index 8fcb4eeb1..e022e6a60 100644 --- a/src/core/cpu_core_manager.cpp +++ b/src/core/cpu_core_manager.cpp @@ -6,6 +6,7 @@ #include "core/arm/exclusive_monitor.h" #include "core/core.h" #include "core/core_cpu.h" +#include "core/core_timing.h" #include "core/cpu_core_manager.h" #include "core/gdbstub/gdbstub.h" #include "core/settings.h" @@ -122,13 +123,19 @@ void CpuCoreManager::RunLoop(bool tight_loop) { } } - for (active_core = 0; active_core < NUM_CPU_CORES; ++active_core) { - cores[active_core]->RunLoop(tight_loop); - if (Settings::values.use_multi_core) { - // Cores 1-3 are run on other threads in this mode - break; + auto& core_timing = system.CoreTiming(); + core_timing.ResetRun(); + bool keep_running{}; + do { + keep_running = false; + for (active_core = 0; active_core < NUM_CPU_CORES; ++active_core) { + core_timing.SwitchContext(active_core); + if (core_timing.CurrentContextCanRun()) { + cores[active_core]->RunLoop(tight_loop); + } + keep_running |= core_timing.CurrentContextCanRun(); } - } + } while (keep_running); if (GDBStub::IsServerEnabled()) { GDBStub::SetCpuStepFlag(false); -- cgit v1.2.3