diff options
author | Morph <39850852+Morph1984@users.noreply.github.com> | 2023-03-02 01:27:10 +0100 |
---|---|---|
committer | Morph <39850852+Morph1984@users.noreply.github.com> | 2023-03-05 07:41:28 +0100 |
commit | 1ed49f92dd56289e6e31a967e602c65ccedd4ff1 (patch) | |
tree | a151df116022445b7606614e31e9b3a3b8225152 /src/common/windows | |
parent | common: Implement a high resolution steady clock (diff) | |
download | yuzu-1ed49f92dd56289e6e31a967e602c65ccedd4ff1.tar yuzu-1ed49f92dd56289e6e31a967e602c65ccedd4ff1.tar.gz yuzu-1ed49f92dd56289e6e31a967e602c65ccedd4ff1.tar.bz2 yuzu-1ed49f92dd56289e6e31a967e602c65ccedd4ff1.tar.lz yuzu-1ed49f92dd56289e6e31a967e602c65ccedd4ff1.tar.xz yuzu-1ed49f92dd56289e6e31a967e602c65ccedd4ff1.tar.zst yuzu-1ed49f92dd56289e6e31a967e602c65ccedd4ff1.zip |
Diffstat (limited to 'src/common/windows')
-rw-r--r-- | src/common/windows/timer_resolution.cpp | 87 | ||||
-rw-r--r-- | src/common/windows/timer_resolution.h | 38 |
2 files changed, 125 insertions, 0 deletions
diff --git a/src/common/windows/timer_resolution.cpp b/src/common/windows/timer_resolution.cpp new file mode 100644 index 000000000..6c2063a4c --- /dev/null +++ b/src/common/windows/timer_resolution.cpp @@ -0,0 +1,87 @@ +// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <windows.h> + +#include "common/windows/timer_resolution.h" + +extern "C" { +// http://undocumented.ntinternals.net/index.html?page=UserMode%2FUndocumented%20Functions%2FTime%2FNtQueryTimerResolution.html +NTSYSAPI LONG NTAPI NtQueryTimerResolution(PULONG MinimumResolution, PULONG MaximumResolution, + PULONG CurrentResolution); + +// http://undocumented.ntinternals.net/index.html?page=UserMode%2FUndocumented%20Functions%2FTime%2FNtSetTimerResolution.html +NTSYSAPI LONG NTAPI NtSetTimerResolution(ULONG DesiredResolution, BOOLEAN SetResolution, + PULONG CurrentResolution); + +// http://undocumented.ntinternals.net/index.html?page=UserMode%2FUndocumented%20Functions%2FNT%20Objects%2FThread%2FNtDelayExecution.html +NTSYSAPI LONG NTAPI NtDelayExecution(BOOLEAN Alertable, PLARGE_INTEGER DelayInterval); +} + +namespace Common::Windows { + +namespace { + +using namespace std::chrono; + +constexpr nanoseconds ToNS(ULONG hundred_ns) { + return nanoseconds{hundred_ns * 100}; +} + +constexpr ULONG ToHundredNS(nanoseconds ns) { + return static_cast<ULONG>(ns.count()) / 100; +} + +struct TimerResolution { + std::chrono::nanoseconds minimum; + std::chrono::nanoseconds maximum; + std::chrono::nanoseconds current; +}; + +TimerResolution GetTimerResolution() { + ULONG MinimumTimerResolution; + ULONG MaximumTimerResolution; + ULONG CurrentTimerResolution; + NtQueryTimerResolution(&MinimumTimerResolution, &MaximumTimerResolution, + &CurrentTimerResolution); + return { + .minimum{ToNS(MinimumTimerResolution)}, + .maximum{ToNS(MaximumTimerResolution)}, + .current{ToNS(CurrentTimerResolution)}, + }; +} + +} // Anonymous namespace + +nanoseconds GetMinimumTimerResolution() { + return GetTimerResolution().minimum; +} + +nanoseconds GetMaximumTimerResolution() { + return GetTimerResolution().maximum; +} + +nanoseconds GetCurrentTimerResolution() { + return GetTimerResolution().current; +} + +nanoseconds SetCurrentTimerResolution(nanoseconds timer_resolution) { + // Set the timer resolution, and return the current timer resolution. + const auto DesiredTimerResolution = ToHundredNS(timer_resolution); + ULONG CurrentTimerResolution; + NtSetTimerResolution(DesiredTimerResolution, TRUE, &CurrentTimerResolution); + return ToNS(CurrentTimerResolution); +} + +nanoseconds SetCurrentTimerResolutionToMaximum() { + return SetCurrentTimerResolution(GetMaximumTimerResolution()); +} + +void SleepForOneTick() { + LARGE_INTEGER DelayInterval{ + .QuadPart{-1}, + }; + NtDelayExecution(FALSE, &DelayInterval); +} + +} // namespace Common::Windows diff --git a/src/common/windows/timer_resolution.h b/src/common/windows/timer_resolution.h new file mode 100644 index 000000000..e1e50a62d --- /dev/null +++ b/src/common/windows/timer_resolution.h @@ -0,0 +1,38 @@ +// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project +// SPDX-License-Identifier: GPL-2.0-or-later + +#pragma once + +#include <chrono> + +namespace Common::Windows { + +/// Returns the minimum (least precise) supported timer resolution in nanoseconds. +std::chrono::nanoseconds GetMinimumTimerResolution(); + +/// Returns the maximum (most precise) supported timer resolution in nanoseconds. +std::chrono::nanoseconds GetMaximumTimerResolution(); + +/// Returns the current timer resolution in nanoseconds. +std::chrono::nanoseconds GetCurrentTimerResolution(); + +/** + * Sets the current timer resolution. + * + * @param timer_resolution Timer resolution in nanoseconds. + * + * @returns The current timer resolution. + */ +std::chrono::nanoseconds SetCurrentTimerResolution(std::chrono::nanoseconds timer_resolution); + +/** + * Sets the current timer resolution to the maximum supported timer resolution. + * + * @returns The current timer resolution. + */ +std::chrono::nanoseconds SetCurrentTimerResolutionToMaximum(); + +/// Sleep for one tick of the current timer resolution. +void SleepForOneTick(); + +} // namespace Common::Windows |