diff options
| author | merry <git@mary.rs> | 2022-04-02 21:05:49 +0100 |
|---|---|---|
| committer | merry <git@mary.rs> | 2022-04-02 22:22:48 +0100 |
| commit | 7470fdd77c362958d3faa752ca381e38c2d08788 (patch) | |
| tree | 791c5fdcc52e9650ebafce30ca4c51b317aa133f /src/common/x64/native_clock.cpp | |
| parent | eeca2f2df9ac0e396f55ab479b26703a9a9a7395 (diff) | |
native_clock: Use writeback from CAS to avoid double-loading
Diffstat (limited to 'src/common/x64/native_clock.cpp')
| -rw-r--r-- | src/common/x64/native_clock.cpp | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/src/common/x64/native_clock.cpp b/src/common/x64/native_clock.cpp index 2a2664e5d5..7a3f21dcf1 100644 --- a/src/common/x64/native_clock.cpp +++ b/src/common/x64/native_clock.cpp @@ -55,8 +55,9 @@ NativeClock::NativeClock(u64 emulated_cpu_frequency_, u64 emulated_clock_frequen u64 NativeClock::GetRTSC() { TimePoint new_time_point{}; TimePoint current_time_point{}; + + current_time_point.pack = Common::AtomicLoad128(time_point.pack.data()); do { - current_time_point.pack = Common::AtomicLoad128(time_point.pack.data()); _mm_mfence(); const u64 current_measure = __rdtsc(); u64 diff = current_measure - current_time_point.inner.last_measure; @@ -66,7 +67,7 @@ u64 NativeClock::GetRTSC() { : current_time_point.inner.last_measure; new_time_point.inner.accumulated_ticks = current_time_point.inner.accumulated_ticks + diff; } while (!Common::AtomicCompareAndSwap(time_point.pack.data(), new_time_point.pack, - current_time_point.pack)); + current_time_point.pack, current_time_point.pack)); /// The clock cannot be more precise than the guest timer, remove the lower bits return new_time_point.inner.accumulated_ticks & inaccuracy_mask; } @@ -75,13 +76,14 @@ void NativeClock::Pause(bool is_paused) { if (!is_paused) { TimePoint current_time_point{}; TimePoint new_time_point{}; + + current_time_point.pack = Common::AtomicLoad128(time_point.pack.data()); do { - current_time_point.pack = Common::AtomicLoad128(time_point.pack.data()); new_time_point.pack = current_time_point.pack; _mm_mfence(); new_time_point.inner.last_measure = __rdtsc(); } while (!Common::AtomicCompareAndSwap(time_point.pack.data(), new_time_point.pack, - current_time_point.pack)); + current_time_point.pack, current_time_point.pack)); } } |