48 lines
2.4 KiB
C++
48 lines
2.4 KiB
C++
/***
|
|
Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.
|
|
|
|
File: WaitFor.hpp
|
|
Date: 2021-6-12
|
|
Author: Reece
|
|
***/
|
|
#pragma once
|
|
|
|
namespace Aurora::Threading
|
|
{
|
|
// the original idea:
|
|
// It's not insane to expect slow linux kernels to run at 250 jiffies a second, so, 4ms
|
|
// It's also not insane to expect a complete context swap/rescheduled yield on windows to last 15ms
|
|
// -> if sleep time greater than 15ms, yield to nt Sleep
|
|
// -> if sleep time greater than 4ms, yield to linux kernel
|
|
// -> if sleep time greater than 2ms (?), yield to SwitchToThread
|
|
// -> SPIIIIIN
|
|
|
|
static const AuUInt64 kPredictedLinuxKernelJiffies = 250; // some kernel builds go up to 1000
|
|
static const AuUInt64 kPredictedLinuxKernelTimeMilli = (1000 / kPredictedLinuxKernelJiffies);
|
|
static const AuUInt64 kPredictedLinuxKernelTimeMicro = kPredictedLinuxKernelTimeMilli * 1000;
|
|
static const AuUInt64 kPredictedLinuxKernelTimeNano = kPredictedLinuxKernelTimeMilli * 1000000;
|
|
static const AuUInt64 kLinuxYieldTimeNano = 1e+6 / 150; // completely arbitrary
|
|
static const AuUInt64 kLinuxYieldTimeThresNano = 1e+6 / 25; // completely arbitrary
|
|
static const AuUInt64 kPredictedLinuxKernelTimeRTNano = (kLinuxYieldTimeNano + kPredictedLinuxKernelTimeNano) * 3;
|
|
|
|
//static const AuUInt64 kPredictedNTOSSwitchTimeMS = 10;
|
|
//static const AuUInt64 kPredictedNTOSSwitchTimeYDMS = kPredictedNTOSSwitchTimeMS / 4;
|
|
//static const AuUInt64 kPredictedNTOSSwitchTimeRTMS = kPredictedNTOSSwitchTimeMS + kPredictedNTOSSwitchTimeMS;
|
|
static const AuUInt64 kPredictedNTOSSwitchTimeRTNS = 1000000;// kPredictedNTOSSwitchTimeRTMS* 1000000;
|
|
//static const AuUInt64 kPredictedNTOSSwitchTimeNS = 3* 1000000;
|
|
static const AuUInt64 kPredictedNTOSSwitchTimeYDNS = 1000000 / 4;// kPredictedNTOSSwitchTimeNS / 4;
|
|
|
|
static const AuMach kYieldFlagsNone = 0;
|
|
static const AuMach kYieldFlagsRemoved = 1;
|
|
static const AuMach kYieldFlagsContextSwitchASAP = 2;
|
|
static const AuMach kYieldFlagsContextSwitchForever = 4;
|
|
static const AuMach kYieldFlagsRegular = kYieldFlagsContextSwitchASAP | kYieldFlagsContextSwitchForever;
|
|
|
|
template<AuMach yieldFaster>
|
|
void FastSnooze(long &count, AuUInt64 &startTime, AuUInt64 maxStallMS);
|
|
|
|
|
|
bool YieldPoll(bool permitMultipleContextSwitches, AuUInt64 timeoutMs, Threading::PollCallback_cb cb);
|
|
|
|
void YieldToOtherThread();
|
|
} |