Files
eden/src/common/thread.cpp
T

Ignoring revisions in .git-blame-ignore-revs. Click here to bypass and see the normal blame view.

731 lines
23 KiB
C++
Raw Normal View History

// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
2025-09-21 21:58:59 +02:00
// SPDX-License-Identifier: GPL-3.0-or-later
2022-04-28 18:24:11 +02:00
// SPDX-FileCopyrightText: 2013 Dolphin Emulator Project
// SPDX-FileCopyrightText: 2014 Citra Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
2013-09-04 20:17:46 -04:00
#include <chrono>
#include <limits>
2021-09-08 14:36:20 -04:00
#include <string>
#include <thread>
2021-09-08 14:36:20 -04:00
#include "common/adpf.h"
2021-09-08 14:36:20 -04:00
#include "common/error.h"
#include "common/logging.h"
#include "common/assert.h"
#include "common/thread.h"
2013-09-04 20:17:46 -04:00
#ifdef __APPLE__
2016-09-18 09:38:01 +09:00
#include <mach/mach.h>
2025-10-22 04:53:40 +02:00
#elif defined(__HAIKU__)
#include <kernel/OS.h>
#elif defined(_WIN32)
2016-12-03 21:08:02 +01:00
#include <windows.h>
#include "common/string_util.h"
#include "common/windows/timer_resolution.h"
2015-06-20 22:45:15 +01:00
#else
2026-03-08 19:32:24 +01:00
#if defined(__FreeBSD__)
#include <sys/cpuset.h>
#include <sys/_cpuset.h>
2016-09-18 09:38:01 +09:00
#include <pthread_np.h>
// Compatibility with CPUset
#define cpu_set_t cpuset_t
2026-03-08 19:32:24 +01:00
#elif defined(__DragonFly__) || defined(__OpenBSD__) || defined(__Bitrig__)
#include <pthread_np.h>
2016-09-18 09:38:01 +09:00
#endif
2025-10-07 06:38:22 +02:00
#include <pthread.h>
2016-09-18 09:38:01 +09:00
#include <sched.h>
2015-06-20 22:45:15 +01:00
#endif
2015-06-20 22:45:15 +01:00
#ifndef _WIN32
2016-09-18 09:38:01 +09:00
#include <unistd.h>
2013-09-04 20:17:46 -04:00
#endif
#ifdef __linux__
#include <sys/resource.h>
#include <algorithm>
namespace {
constexpr int NICE_AUDIO = -16;
constexpr int NICE_URGENT_DISPLAY = -8;
constexpr int NICE_DISPLAY = -4;
constexpr int NICE_DEFAULT = 0;
constexpr int NICE_BACKGROUND = 10;
int LowestAllowedNice() {
static const int lowest = [] {
rlimit limit{};
if (getrlimit(RLIMIT_NICE, &limit) != 0) {
return 0;
}
if (limit.rlim_cur >= 40) {
return -20;
}
return 20 - static_cast<int>(limit.rlim_cur);
}();
return lowest;
}
int NiceValueForPriority(Common::ThreadPriority priority) {
const int wanted = [priority] {
switch (priority) {
case Common::ThreadPriority::Low: return NICE_BACKGROUND;
case Common::ThreadPriority::Normal: return NICE_DEFAULT;
case Common::ThreadPriority::High: return NICE_DISPLAY;
case Common::ThreadPriority::VeryHigh: return NICE_URGENT_DISPLAY;
case Common::ThreadPriority::Critical: return NICE_AUDIO;
default: return NICE_DEFAULT;
}
}();
return (std::max)(wanted, (std::min)(NICE_DEFAULT, LowestAllowedNice()));
}
} // Anonymous namespace
#endif
#ifdef __ANDROID__
#include <sys/utsname.h>
#include <atomic>
#include <cerrno>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <fstream>
#include <mutex>
#include <vector>
namespace {
constexpr size_t ANDROID_MINIMUM_PERFORMANCE_CORES = 4;
// A core counts as a performance core while it is within this much of the fastest one.
constexpr s64 ANDROID_PERFORMANCE_CAPACITY_PERCENT = 50;
constexpr std::chrono::nanoseconds ANDROID_POLICY_POLL_INTERVAL = std::chrono::milliseconds{500};
enum class CoreGroup {
Unrestricted,
Performance,
Efficiency,
};
struct ThreadPolicy {
pid_t tid;
CoreGroup group;
s32 nice_value;
bool has_nice;
};
struct CoreInfo {
s64 weight;
u64 midr;
s32 cpu;
};
struct CpuTopologyState {
std::mutex topology_mutex;
cpu_set_t allowed{};
cpu_set_t performance{};
cpu_set_t efficiency{};
bool separated = false;
bool initialized = false;
pid_t canary_tid = 0;
cpu_set_t canary_mask{};
bool canary_valid = false;
std::atomic<s64> next_poll_ns{0};
std::mutex policy_mutex;
std::vector<ThreadPolicy> policies;
};
CpuTopologyState& State() {
static CpuTopologyState* const state = new CpuTopologyState();
return *state;
}
struct PolicyRegistration {
~PolicyRegistration() {
const pid_t tid = gettid();
::Common::ADPF::RemoveCurrentThread();
CpuTopologyState& state = State();
std::scoped_lock lock{state.policy_mutex};
std::erase_if(state.policies,
[tid](const ThreadPolicy& policy) { return policy.tid == tid; });
}
};
thread_local PolicyRegistration t_policy_registration;
s32 PossibleCpuCount() {
std::ifstream file("/sys/devices/system/cpu/possible");
std::string list;
if (file && std::getline(file, list) && !list.empty()) {
s64 highest = -1;
const char* cursor = list.c_str();
while (*cursor != '\0') {
char* end = nullptr;
const s64 value = std::strtol(cursor, &end, 10);
if (end == cursor) {
break;
}
highest = (std::max)(highest, value);
cursor = end;
while (*cursor == '-' || *cursor == ',') {
++cursor;
}
}
if (highest >= 0) {
return static_cast<s32>((std::min<s64>)(highest + 1, CPU_SETSIZE));
}
}
const s64 configured = sysconf(_SC_NPROCESSORS_CONF);
if (configured > 0) {
return static_cast<s32>((std::min<s64>)(configured, CPU_SETSIZE));
}
return static_cast<s32>((std::min<s64>)(std::thread::hardware_concurrency(), CPU_SETSIZE));
}
s64 ReadCpuScalar(s32 cpu, const char* node) {
s64 value = 0;
std::ifstream file("/sys/devices/system/cpu/cpu" + std::to_string(cpu) + "/" + node);
if (!file || !(file >> value) || value <= 0) {
return 0;
}
return value;
}
u64 ReadCpuMidr(s32 cpu) {
u64 midr = 0;
std::ifstream file("/sys/devices/system/cpu/cpu" + std::to_string(cpu) +
"/regs/identification/midr_el1");
if (!file || !(file >> std::hex >> midr)) {
return 0;
}
return midr;
}
std::vector<CoreInfo> CollectCores(const cpu_set_t& allowed, s32 total, const char* node,
bool require_all) {
std::vector<CoreInfo> cores;
for (s32 cpu = 0; cpu < total; ++cpu) {
if (!CPU_ISSET(cpu, &allowed)) {
continue;
}
const s64 weight = ReadCpuScalar(cpu, node);
if (weight <= 0) {
if (require_all) {
return {};
}
LOG_WARNING(Common, "Could not read {} for CPU {}, treating it as an efficiency core",
node, cpu);
continue;
}
cores.push_back(CoreInfo{weight, ReadCpuMidr(cpu), cpu});
}
return cores;
}
bool WeightsAreUniform(const std::vector<CoreInfo>& cores) {
return std::all_of(cores.begin(), cores.end(),
[&](const CoreInfo& core) { return core.weight == cores.front().weight; });
}
bool MidrsAreDistinct(const std::vector<CoreInfo>& cores) {
return std::none_of(cores.begin(), cores.end(),
[](const CoreInfo& core) { return core.midr == 0; }) &&
std::any_of(cores.begin(), cores.end(),
[&](const CoreInfo& core) { return core.midr != cores.front().midr; });
}
void ComputeTopologyLocked(CpuTopologyState& state) {
state.initialized = true;
state.separated = false;
CPU_ZERO(&state.allowed);
CPU_ZERO(&state.performance);
CPU_ZERO(&state.efficiency);
if (sched_getaffinity(getpid(), sizeof(state.allowed), &state.allowed) != 0) {
LOG_WARNING(Common, "Could not query process CPU affinity: {}",
::Common::GetLastErrorMsg());
return;
}
const s32 total = PossibleCpuCount();
auto cores = CollectCores(state.allowed, total, "cpu_capacity", true);
if (cores.empty() || (WeightsAreUniform(cores) && MidrsAreDistinct(cores))) {
auto by_frequency = CollectCores(state.allowed, total, "cpufreq/cpuinfo_max_freq", false);
if (!by_frequency.empty()) {
cores = std::move(by_frequency);
}
}
if (cores.empty()) {
LOG_WARNING(Common, "Could not determine CPU topology, thread placement is disabled");
return;
}
if (WeightsAreUniform(cores)) {
if (MidrsAreDistinct(cores)) {
LOG_WARNING(Common, "CPU clusters differ but rank identically, thread placement is "
"disabled");
} else {
LOG_INFO(Common, "CPU cores are symmetric, thread placement is disabled");
}
return;
}
std::sort(cores.begin(), cores.end(), [](const CoreInfo& lhs, const CoreInfo& rhs) {
if (lhs.weight != rhs.weight) {
return lhs.weight > rhs.weight;
}
return lhs.cpu < rhs.cpu;
});
const s64 fastest = cores.front().weight;
size_t taken = 0;
for (const auto& core : cores) {
const bool fast_enough =
core.weight * 100 >= fastest * ANDROID_PERFORMANCE_CAPACITY_PERCENT;
if (!fast_enough && taken >= ANDROID_MINIMUM_PERFORMANCE_CORES) {
break;
}
CPU_SET(core.cpu, &state.performance);
++taken;
}
if (taken == 0) {
return;
}
for (s32 cpu = 0; cpu < total; ++cpu) {
if (CPU_ISSET(cpu, &state.allowed) && !CPU_ISSET(cpu, &state.performance)) {
CPU_SET(cpu, &state.efficiency);
}
}
state.separated = CPU_COUNT(&state.efficiency) > 0;
LOG_INFO(Common, "CPU topology: {} performance cores, {} efficiency cores, separation {}",
CPU_COUNT(&state.performance), CPU_COUNT(&state.efficiency),
state.separated ? "enabled" : "unavailable");
}
void EnsureTopologyLocked(CpuTopologyState& state) {
if (!state.initialized) {
ComputeTopologyLocked(state);
}
}
void RefreshTopologyLocked(CpuTopologyState& state) {
if (!state.initialized) {
ComputeTopologyLocked(state);
return;
}
cpu_set_t current;
CPU_ZERO(&current);
if (sched_getaffinity(getpid(), sizeof(current), &current) != 0) {
return;
}
if (std::memcmp(&current, &state.allowed, sizeof(current)) != 0) {
ComputeTopologyLocked(state);
}
}
bool ApplyCoreGroupLocked(CpuTopologyState& state, pid_t tid, CoreGroup group,
bool* gone = nullptr) {
const bool restrict_group = group != CoreGroup::Unrestricted && state.separated;
const cpu_set_t* mask = &state.allowed;
if (restrict_group) {
mask = group == CoreGroup::Performance ? &state.performance : &state.efficiency;
}
if (CPU_COUNT(mask) == 0) {
return false;
}
if (sched_setaffinity(tid, sizeof(*mask), mask) != 0) {
if (gone != nullptr && errno == ESRCH) {
*gone = true;
return false;
}
LOG_WARNING(Common, "Could not restrict thread {} to its core group: {}", tid,
::Common::GetLastErrorMsg());
return false;
}
return true;
}
bool KernelPreservesRequestedAffinity() {
utsname info{};
if (uname(&info) != 0) {
return false;
}
s32 major = 0;
s32 minor = 0;
if (std::sscanf(info.release, "%d.%d", &major, &minor) != 2) {
return false;
}
return major > 6 || (major == 6 && minor >= 2);
}
void SnapshotCanaryLocked(CpuTopologyState& state) {
state.canary_valid = false;
if (!state.separated) {
return;
}
for (const auto& policy : state.policies) {
if (policy.group == CoreGroup::Unrestricted) {
continue;
}
cpu_set_t mask;
CPU_ZERO(&mask);
if (sched_getaffinity(policy.tid, sizeof(mask), &mask) != 0) {
continue;
}
state.canary_tid = policy.tid;
state.canary_mask = mask;
state.canary_valid = true;
return;
}
}
bool DueForPoll(CpuTopologyState& state) {
const auto now = std::chrono::steady_clock::now().time_since_epoch();
const s64 now_ns = std::chrono::duration_cast<std::chrono::nanoseconds>(now).count();
s64 next = state.next_poll_ns.load(std::memory_order_relaxed);
if (now_ns < next) {
return false;
}
return state.next_poll_ns.compare_exchange_strong(
next, now_ns + ANDROID_POLICY_POLL_INTERVAL.count(), std::memory_order_relaxed);
}
ThreadPolicy& AcquirePolicyLocked(CpuTopologyState& state, pid_t tid) {
for (auto& policy : state.policies) {
if (policy.tid == tid) {
return policy;
}
}
return state.policies.emplace_back(ThreadPolicy{tid, CoreGroup::Unrestricted, 0, false});
}
void SetCurrentThreadCoreGroup(CoreGroup group) {
const pid_t tid = gettid();
(void)&t_policy_registration;
CoreGroup effective = group;
if (tid == getpid() && group != CoreGroup::Unrestricted) {
LOG_WARNING(Common, "Refusing to place the main thread: the CPU topology is read from it");
effective = CoreGroup::Unrestricted;
}
CpuTopologyState& state = State();
std::scoped_lock topology_lock{state.topology_mutex};
EnsureTopologyLocked(state);
ApplyCoreGroupLocked(state, tid, effective);
std::scoped_lock policy_lock{state.policy_mutex};
AcquirePolicyLocked(state, tid).group = effective;
if (!state.canary_valid) {
SnapshotCanaryLocked(state);
}
}
void RememberCurrentThreadNice(pid_t tid, s32 nice_value) {
(void)&t_policy_registration;
CpuTopologyState& state = State();
std::scoped_lock lock{state.policy_mutex};
ThreadPolicy& policy = AcquirePolicyLocked(state, tid);
policy.nice_value = nice_value;
policy.has_nice = true;
}
} // Anonymous namespace
#endif
#include "common/cpu_features.h"
#ifdef ARCHITECTURE_x86_64
#ifdef _MSC_VER
#include <intrin.h>
#else
#include <x86intrin.h>
#endif
#include "common/x64/rdtsc.h"
#endif
2016-09-18 09:38:01 +09:00
namespace Common {
2013-09-04 20:17:46 -04:00
void SetCurrentThreadPriority(ThreadPriority new_priority) {
2025-10-22 04:53:40 +02:00
#ifdef _WIN32
int windows_priority = [&]() {
switch (new_priority) {
case ThreadPriority::Low: return THREAD_PRIORITY_BELOW_NORMAL;
case ThreadPriority::Normal: return THREAD_PRIORITY_NORMAL;
case ThreadPriority::High: return THREAD_PRIORITY_ABOVE_NORMAL;
case ThreadPriority::VeryHigh: return THREAD_PRIORITY_HIGHEST;
case ThreadPriority::Critical: return THREAD_PRIORITY_TIME_CRITICAL;
default: return THREAD_PRIORITY_NORMAL;
}
}();
SetThreadPriority(GetCurrentThread(), windows_priority);
#elif defined(__HAIKU__)
// TODO: We have priorities for 3D rendering applications - may help lavapipe?
int priority = [&]() {
switch (new_priority) {
case ThreadPriority::Low: return B_LOW_PRIORITY;
case ThreadPriority::Normal: return B_NORMAL_PRIORITY;
case ThreadPriority::High: return B_DISPLAY_PRIORITY;
case ThreadPriority::VeryHigh: return B_URGENT_DISPLAY_PRIORITY;
case ThreadPriority::Critical: return B_URGENT_PRIORITY;
default: return B_NORMAL_PRIORITY;
}
}();
set_thread_priority(find_thread(NULL), priority);
#elif defined(__ANDROID__)
const int nice_value = NiceValueForPriority(new_priority);
const pid_t tid = gettid();
if (setpriority(PRIO_PROCESS, static_cast<id_t>(tid), nice_value) != 0) {
LOG_WARNING(Common, "Could not set thread nice value to {}: {}", nice_value,
GetLastErrorMsg());
return;
}
RememberCurrentThreadNice(tid, nice_value);
#elif defined(__linux__)
const int nice_value = NiceValueForPriority(new_priority);
if (setpriority(PRIO_PROCESS, 0, nice_value) != 0) {
LOG_DEBUG(Common, "Could not set thread nice value to {}: {}", nice_value,
GetLastErrorMsg());
}
#else
const s32 max_prio = sched_get_priority_max(SCHED_OTHER);
const s32 min_prio = sched_get_priority_min(SCHED_OTHER);
if (max_prio > min_prio) {
const u32 level = (std::min)(static_cast<u32>(new_priority), 4U);
sched_param params{};
params.sched_priority =
min_prio + static_cast<s32>(static_cast<u32>(max_prio - min_prio) * level) / 4;
pthread_setschedparam(pthread_self(), SCHED_OTHER, &params);
}
#endif
2025-10-22 04:53:40 +02:00
}
void SetCurrentThreadName(const char* name) {
#ifdef _MSC_VER
// Sets the debugger-visible name of the current thread.
if (auto pf = (decltype(&SetThreadDescription))(void*)GetProcAddress(GetModuleHandle(TEXT("KernelBase.dll")), "SetThreadDescription"); pf)
2025-11-03 21:06:51 +01:00
pf(GetCurrentThread(), UTF8ToUTF16W(name).data()); // Windows 10+
else
; // No-op
#elif defined(__APPLE__)
pthread_setname_np(name);
2025-10-07 06:38:22 +02:00
#elif defined(__HAIKU__)
rename_thread(find_thread(NULL), name);
#elif defined(__Bitrig__) || defined(__DragonFly__) || defined(__FreeBSD__) || defined(__OpenBSD__)
pthread_set_name_np(pthread_self(), name);
#elif defined(__NetBSD__)
pthread_setname_np(pthread_self(), "%s", (void*)name);
2025-10-07 06:38:22 +02:00
#elif defined(__linux__) || defined(__CYGWIN__) || defined(__sun__) || defined(__glibc__) || defined(__managarm__)
int ret = pthread_setname_np(pthread_self(), name);
if (ret == ERANGE) {
// Linux limits thread names to 15 characters and will outright reject any
// attempt to set a longer name with ERANGE.
char buf[16];
size_t const len = std::min<size_t>(std::strlen(name), sizeof(buf) - 1);
std::memcpy(buf, name, len);
buf[len] = '\0';
pthread_setname_np(pthread_self(), buf);
}
#elif defined(_WIN32)
// MinGW with the POSIX threading model does not support pthread_setname_np
// See for reference
// https://gitlab.freedesktop.org/mesa/mesa/-/blame/main/src/util/u_thread.c?ref_type=heads#L75
2025-10-07 06:38:22 +02:00
(void)name;
2013-09-04 20:17:46 -04:00
#else
pthread_setname_np(pthread_self(), name);
2013-09-04 20:17:46 -04:00
#endif
}
void SetCurrentThreadToPerformanceCores() {
#if defined(__ANDROID__)
if (ADPF::AddCurrentThread(ADPF::Session::Render)) {
SetCurrentThreadCoreGroup(CoreGroup::Unrestricted);
return;
}
SetCurrentThreadCoreGroup(CoreGroup::Performance);
2013-09-04 20:17:46 -04:00
#endif
}
void SetCurrentThreadToEfficiencyCores() {
#if defined(__ANDROID__)
if (ADPF::AddCurrentThread(ADPF::Session::Background)) {
SetCurrentThreadCoreGroup(CoreGroup::Unrestricted);
return;
}
SetCurrentThreadCoreGroup(CoreGroup::Efficiency);
#endif
}
void SetCurrentThreadToBackgroundWork() {
#if defined(__ANDROID__)
ADPF::AddCurrentThread(ADPF::Session::Background);
SetCurrentThreadCoreGroup(CoreGroup::Unrestricted);
#endif
}
void SetCurrentThreadToAllCores() {
#if defined(__ANDROID__)
ADPF::RemoveCurrentThread();
SetCurrentThreadCoreGroup(CoreGroup::Unrestricted);
#endif
}
void RefreshThreadPolicies() {
#if defined(__ANDROID__)
CpuTopologyState& state = State();
std::scoped_lock topology_lock{state.topology_mutex};
RefreshTopologyLocked(state);
std::scoped_lock policy_lock{state.policy_mutex};
std::erase_if(state.policies, [&state](const ThreadPolicy& policy) {
bool gone = false;
if (policy.has_nice &&
setpriority(PRIO_PROCESS, static_cast<id_t>(policy.tid), policy.nice_value) != 0 &&
errno == ESRCH) {
gone = true;
}
if (!gone) {
ApplyCoreGroupLocked(state, policy.tid, policy.group, &gone);
}
return gone;
});
SnapshotCanaryLocked(state);
#endif
}
void PollThreadPolicies() {
#if defined(__ANDROID__)
static const bool needed = !KernelPreservesRequestedAffinity();
if (!needed) {
return;
}
CpuTopologyState& state = State();
if (!DueForPoll(state)) {
return;
}
pid_t tid;
cpu_set_t expected;
{
std::scoped_lock lock{state.topology_mutex};
if (!state.canary_valid) {
return;
}
tid = state.canary_tid;
expected = state.canary_mask;
}
cpu_set_t current;
CPU_ZERO(&current);
if (sched_getaffinity(tid, sizeof(current), &current) == 0 &&
std::memcmp(&current, &expected, sizeof(current)) == 0) {
return;
}
RefreshThreadPolicies();
#endif
}
2013-09-04 20:17:46 -04:00
#ifdef ARCHITECTURE_x86_64
// On Linux and UNIX systems, a futex would nominally be used to cover the costs
// the idea is that it's intuitivelly cheaper to use a direct instruction as opposed to a full futex call
// the underlying libc++ implementation uses pthread_cond_timedwait which MAY invoke a futex
// Let's pretend the OS is too expensive to jump into, and avoid ANY context switches
// this should *IN THEORY* lower CPU usage while just waiting for stuff effectively
// For windows the minimal quanta resolution is about 500us, and normal CRT cond var is 1.5ms(?)
// so may as well avoid that too
// Let's just give ALL platforms the same mechanisms (almost) for when they have umonitor OR waitpkg
#ifdef __clang__
__attribute__((target("waitpkg,mwaitx")))
#elif defined(__GNUC__)
#pragma GCC target("waitpkg")
#pragma GCC target("mwaitx")
#endif
bool Event::WaitFor(const std::chrono::nanoseconds time) {
#ifdef _WIN32
auto const start = Common::X64::FencedRDTSC();
auto const& caps = Common::g_cpu_caps;
[[maybe_unused]] auto const end = start + Common::g_wall_clock.NsToTicks(time);
if (caps.monitorx) {
while (true) {
// Armed monitor, as per manual, MWAITX must be conditional if the condition isn't satisfied
// to prevent a race condition.
_mm_monitorx(reinterpret_cast<u64*>(std::addressof(is_set)), 0, 0);
if (!is_set.load()) {
// RDTSC may be fenced here due to atomic load
#ifdef _MSC_VER
auto const now = __rdtsc();
#else
auto const now = _rdtsc();
#endif
if (end > now) {
u32 const cycles = std::min<u32>((std::numeric_limits<u32>::max)(), s64(end) - s64(now));
// See here: https://github.com/torvalds/linux/blob/948a64995aca6820abefd17f1a4258f5835c5ad9/arch/x86/lib/delay.c#L93
// MWAITX accepts a 32-bit input timer which determines the total number of cycles to wait for
// NOT THE TOTAL ABSOLUTE TSC VALUE, it's just a delta
// BIT[1] = use a timer
// Hint = 0: Use C1 state when sleepy (means slower wakeup but better savings)
_mm_mwaitx(1 << 1, 0u, cycles);
if (!is_set.load())
return false;
} else
return false; //timeout
}
bool expected = true;
if (is_set.compare_exchange_weak(expected, false, std::memory_order_release))
return true;
}
} else if (caps.waitpkg) {
// #UD If CPUID.7.0:ECX.WAITPKG[bit 5]=0.
while (true) {
_umonitor(std::addressof(is_set));
if (!is_set.load() && !_umwait(0, end)) //umwait is absolute time!!!
return false;
bool expected = true;
if (is_set.compare_exchange_weak(expected, false, std::memory_order_release))
return true;
}
} else {
#ifdef _MSC_VER
while (!is_set.load() && end > __rdtsc())
Common::Windows::SleepForOneTick();
#else
while (!is_set.load() && end > _rdtsc())
Common::Windows::SleepForOneTick();
#endif
if (is_set.load())
Reset();
return true;
}
#else
std::unique_lock lk{mutex};
if (!condvar.wait_for(lk, time, [this] { return is_set.load(); }))
return false;
is_set = false;
return true;
#endif
}
#else
bool Event::WaitFor(const std::chrono::nanoseconds time) {
#ifdef _WIN32
auto const end = Common::g_wall_clock.GetTimeNS() + time;
while (!is_set.load() && end > Common::g_wall_clock.GetTimeNS())
Common::Windows::SleepForOneTick();
if (is_set.load())
Reset();
return true;
#else
std::unique_lock lk{mutex};
if (!condvar.wait_for(lk, time, [this] { return is_set.load(); }))
return false;
is_set = false;
return true;
#endif
}
#endif
2013-09-04 20:17:46 -04:00
} // namespace Common