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Merged
merged 10 commits into from
Jan 28, 2023
Merged

SuspendingClock on Windows does not suspend #63225

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27c684f
SuspendingClock on Windows does not suspend #63224
grynspan Jan 25, 2023
aaace52
Fix inaccurate values for swift_get_clock_res() on Windows
grynspan Jan 25, 2023
95c0926
QueryUnbiasedInterruptTimePrecise() isn't always available so it must…
grynspan Jan 26, 2023
07f8b2d
- Add more comments explaining why we use GetProcAddress().
grynspan Jan 26, 2023
9d0cec5
Do 128-bit math with clang extensions instead of MSVC++ extensions/in…
grynspan Jan 26, 2023
48a5fb3
Use swift_Concurrency_fatalError() instead of swift::fatalError() (oops)
grynspan Jan 26, 2023
9af8d99
Remove commented-out MSVC++ 128-bit math
grynspan Jan 26, 2023
5444f22
Don't need immintrin.h
grynspan Jan 27, 2023
5191939
Get rid of redundant timespecs
grynspan Jan 27, 2023
4757e68
Every platform has time.h, so remove the HAS_TIME check
grynspan Jan 27, 2023
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147 changes: 71 additions & 76 deletions stdlib/public/Concurrency/Clock.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -11,17 +11,18 @@
//===----------------------------------------------------------------------===//

#include "swift/Runtime/Concurrency.h"
#include "swift/Runtime/Once.h"

#if __has_include(<time.h>)
#define HAS_TIME 1
#include <time.h>
#endif
#if defined(_WIN32)
#define WIN32_LEAN_AND_MEAN
#define NOMINMAX
#include <Windows.h>
#include <realtimeapiset.h>
#endif

#include "Error.h"

using namespace swift;

SWIFT_EXPORT_FROM(swift_Concurrency)
Expand All @@ -32,80 +33,83 @@ void swift_get_time(
swift_clock_id clock_id) {
switch (clock_id) {
case swift_clock_id_continuous: {
#if defined(__linux__) && HAS_TIME
struct timespec continuous;
#if defined(__linux__)
clock_gettime(CLOCK_BOOTTIME, &continuous);
*seconds = continuous.tv_sec;
*nanoseconds = continuous.tv_nsec;
#elif defined(__APPLE__) && HAS_TIME
struct timespec continuous;
#elif defined(__APPLE__)
clock_gettime(CLOCK_MONOTONIC_RAW, &continuous);
*seconds = continuous.tv_sec;
*nanoseconds = continuous.tv_nsec;
#elif (defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__wasi__)) && HAS_TIME
struct timespec continuous;
#elif (defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__wasi__))
clock_gettime(CLOCK_MONOTONIC, &continuous);
*seconds = continuous.tv_sec;
*nanoseconds = continuous.tv_nsec;
#elif defined(_WIN32)
LARGE_INTEGER freq;
QueryPerformanceFrequency(&freq);
LARGE_INTEGER count;
QueryPerformanceCounter(&count);
*seconds = count.QuadPart / freq.QuadPart;
if (freq.QuadPart < 1000000000) {
*nanoseconds =
((count.QuadPart % freq.QuadPart) * 1000000000) / freq.QuadPart;
} else {
*nanoseconds =
(count.QuadPart % freq.QuadPart) * (1000000000.0 / freq.QuadPart);
}
// Divide count (number of ticks) by frequency (number of ticks per
// second) to get the counter in seconds. We also need to multiply the
// count by 1,000,000,000 to get nanosecond resolution. By multiplying
// first, we maintain high precision. The resulting value is the tick
// count in nanoseconds. Use 128-bit math to avoid overflowing.
auto quadPart = static_cast<unsigned __int128>(count.QuadPart);
auto ns = (quadPart * 1'000'000'000) / freq.QuadPart;
continuous.tv_sec = ns / 1'000'000'000;
continuous.tv_nsec = ns % 1'000'000'000;
#else
#error Missing platform continuous time definition
#endif
*seconds = continuous.tv_sec;
*nanoseconds = continuous.tv_nsec;
return;
}
case swift_clock_id_suspending: {
#if defined(__linux__) && HAS_TIME
struct timespec suspending;
#if defined(__linux__)
clock_gettime(CLOCK_MONOTONIC, &suspending);
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
#elif defined(__APPLE__) && HAS_TIME
struct timespec suspending;
#elif defined(__APPLE__)
clock_gettime(CLOCK_UPTIME_RAW, &suspending);
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
#elif defined(__wasi__) && HAS_TIME
struct timespec suspending;
#elif defined(__wasi__)
clock_gettime(CLOCK_MONOTONIC, &suspending);
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
#elif (defined(__OpenBSD__) || defined(__FreeBSD__)) && HAS_TIME
struct timespec suspending;
#elif (defined(__OpenBSD__) || defined(__FreeBSD__))
clock_gettime(CLOCK_UPTIME, &suspending);
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
#elif defined(_WIN32)
LARGE_INTEGER freq;
QueryPerformanceFrequency(&freq);
LARGE_INTEGER count;
QueryPerformanceCounter(&count);
*seconds = count.QuadPart / freq.QuadPart;
if (freq.QuadPart < 1000000000) {
*nanoseconds =
((count.QuadPart % freq.QuadPart) * 1000000000) / freq.QuadPart;
// QueryUnbiasedInterruptTimePrecise() was added in Windows 10 and is, as
// the name suggests, more precise than QueryUnbiasedInterruptTime().
// Unfortunately, the symbol is not listed in any .lib file in the SDK and
// must be looked up dynamically at runtime even if our minimum deployment
// target is Windows 10.
typedef decltype(QueryUnbiasedInterruptTimePrecise) *QueryUITP_FP;
static QueryUITP_FP queryUITP = nullptr;
static swift::once_t onceToken;
swift::once(onceToken, [] {
if (HMODULE hKernelBase = GetModuleHandleW(L"KernelBase.dll")) {
queryUITP = reinterpret_cast<QueryUITP_FP>(
GetProcAddress(hKernelBase, "QueryUnbiasedInterruptTimePrecise")
);
}
});

// Call whichever API is available. Both output a value measured in 100ns
// units. We must divide the output by 10,000,000 to get a value in
// seconds and multiply the remainder by 100 to get nanoseconds.
ULONGLONG unbiasedTime;
if (queryUITP) {
(* queryUITP)(&unbiasedTime);
} else {
*nanoseconds =
(count.QuadPart % freq.QuadPart) * (1000000000.0 / freq.QuadPart);
// Fall back to the older, less precise API.
(void)QueryUnbiasedInterruptTime(&unbiasedTime);
}
suspending.tv_sec = unbiasedTime / 10'000'000;
suspending.tv_nsec = (unbiasedTime % 10'000'000) * 100;
#else
#error Missing platform suspending time definition
#endif
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
return;
}
}
abort(); // Invalid clock_id
swift_Concurrency_fatalError(0, "Fatal error: invalid clock ID %d\n",
clock_id);
}

SWIFT_EXPORT_FROM(swift_Concurrency)
Expand All @@ -116,55 +120,46 @@ void swift_get_clock_res(
swift_clock_id clock_id) {
switch (clock_id) {
case swift_clock_id_continuous: {
#if defined(__linux__) && HAS_TIME
struct timespec continuous;
#if defined(__linux__)
clock_getres(CLOCK_BOOTTIME, &continuous);
*seconds = continuous.tv_sec;
*nanoseconds = continuous.tv_nsec;
#elif defined(__APPLE__) && HAS_TIME
struct timespec continuous;
#elif defined(__APPLE__)
clock_getres(CLOCK_MONOTONIC_RAW, &continuous);
*seconds = continuous.tv_sec;
*nanoseconds = continuous.tv_nsec;
#elif (defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__wasi__)) && HAS_TIME
struct timespec continuous;
#elif (defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__wasi__))
clock_getres(CLOCK_MONOTONIC, &continuous);
*seconds = continuous.tv_sec;
*nanoseconds = continuous.tv_nsec;
#elif defined(_WIN32)
*seconds = 0;
*nanoseconds = 1000;
LARGE_INTEGER freq;
QueryPerformanceFrequency(&freq);
continuous.tv_sec = 0;
continuous.tv_nsec = 1'000'000'000 / freq.QuadPart;
#else
#error Missing platform continuous time definition
#endif
*seconds = continuous.tv_sec;
*nanoseconds = continuous.tv_nsec;
return;
}
case swift_clock_id_suspending: {
struct timespec suspending;
#if defined(__linux__) && HAS_TIME
#if defined(__linux__)
clock_getres(CLOCK_MONOTONIC_RAW, &suspending);
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
#elif defined(__APPLE__) && HAS_TIME
#elif defined(__APPLE__)
clock_getres(CLOCK_UPTIME_RAW, &suspending);
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
#elif defined(__wasi__) && HAS_TIME
#elif defined(__wasi__)
clock_getres(CLOCK_MONOTONIC, &suspending);
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
#elif (defined(__OpenBSD__) || defined(__FreeBSD__)) && HAS_TIME
#elif (defined(__OpenBSD__) || defined(__FreeBSD__))
clock_getres(CLOCK_UPTIME, &suspending);
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
#elif defined(_WIN32)
*seconds = 0;
*nanoseconds = 1000;
suspending.tv_sec = 0;
suspending.tv_nsec = 100;
#else
#error Missing platform suspending time definition
#endif
*seconds = suspending.tv_sec;
*nanoseconds = suspending.tv_nsec;
return;
}
}
abort(); // Invalid clock_id
swift_Concurrency_fatalError(0, "Fatal error: invalid clock ID %d\n",
clock_id);
}