diff options
Diffstat (limited to 'src/common/x64')
-rw-r--r-- | src/common/x64/cpu_detect.cpp | 12 | ||||
-rw-r--r-- | src/common/x64/native_clock.cpp | 36 |
2 files changed, 18 insertions, 30 deletions
diff --git a/src/common/x64/cpu_detect.cpp b/src/common/x64/cpu_detect.cpp index fccd2eee5..fbeacc7e2 100644 --- a/src/common/x64/cpu_detect.cpp +++ b/src/common/x64/cpu_detect.cpp @@ -71,9 +71,6 @@ static CPUCaps Detect() { else caps.manufacturer = Manufacturer::Unknown; - u32 family = {}; - u32 model = {}; - __cpuid(cpu_id, 0x80000000); u32 max_ex_fn = cpu_id[0]; @@ -84,15 +81,6 @@ static CPUCaps Detect() { // Detect family and other miscellaneous features if (max_std_fn >= 1) { __cpuid(cpu_id, 0x00000001); - family = (cpu_id[0] >> 8) & 0xf; - model = (cpu_id[0] >> 4) & 0xf; - if (family == 0xf) { - family += (cpu_id[0] >> 20) & 0xff; - } - if (family >= 6) { - model += ((cpu_id[0] >> 16) & 0xf) << 4; - } - if ((cpu_id[3] >> 25) & 1) caps.sse = true; if ((cpu_id[3] >> 26) & 1) diff --git a/src/common/x64/native_clock.cpp b/src/common/x64/native_clock.cpp index 87de40624..82ee2c8a1 100644 --- a/src/common/x64/native_clock.cpp +++ b/src/common/x64/native_clock.cpp @@ -15,26 +15,26 @@ namespace Common { u64 EstimateRDTSCFrequency() { - const auto milli_10 = std::chrono::milliseconds{10}; - // get current time + // Discard the first result measuring the rdtsc. _mm_mfence(); - const u64 tscStart = __rdtsc(); - const auto startTime = std::chrono::high_resolution_clock::now(); - // wait roughly 3 seconds - while (true) { - auto milli = std::chrono::duration_cast<std::chrono::milliseconds>( - std::chrono::high_resolution_clock::now() - startTime); - if (milli.count() >= 3000) - break; - std::this_thread::sleep_for(milli_10); - } - const auto endTime = std::chrono::high_resolution_clock::now(); + __rdtsc(); + std::this_thread::sleep_for(std::chrono::milliseconds{1}); + _mm_mfence(); + __rdtsc(); + + // Get the current time. + const auto start_time = std::chrono::steady_clock::now(); + _mm_mfence(); + const u64 tsc_start = __rdtsc(); + // Wait for 200 milliseconds. + std::this_thread::sleep_for(std::chrono::milliseconds{200}); + const auto end_time = std::chrono::steady_clock::now(); _mm_mfence(); - const u64 tscEnd = __rdtsc(); - // calculate difference - const u64 timer_diff = - std::chrono::duration_cast<std::chrono::nanoseconds>(endTime - startTime).count(); - const u64 tsc_diff = tscEnd - tscStart; + const u64 tsc_end = __rdtsc(); + // Calculate differences. + const u64 timer_diff = static_cast<u64>( + std::chrono::duration_cast<std::chrono::nanoseconds>(end_time - start_time).count()); + const u64 tsc_diff = tsc_end - tsc_start; const u64 tsc_freq = MultiplyAndDivide64(tsc_diff, 1000000000ULL, timer_diff); return tsc_freq; } |