Modified source engine (2017) developed by valve and leaked in 2020. Not for commercial purporses
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

183 lines
7.4 KiB

//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose:
//
//=============================================================================
#ifndef RELIABLETIMER_H
#define RELIABLETIMER_H
#include "tier0/dbg.h"
//#include "constants.h"
#include "tier0/fasttimer.h"
#include "tier1/tier1.h"
#include "tier1/strtools.h"
// #define DbgAssert Assert
#define kMILLION (1000000)
#define kTHOUSAND (1000)
// Timer class that uses QueryPerformanceCounter. This is heavier-weight than CFastTimer which uses rdtsc,
// but this is reliable on multi-core systems whereas CFastTimer is not.
class CReliableTimer
{
public:
CReliableTimer();
void Start();
void End();
int64 GetMicroseconds();
int64 GetMilliseconds();
void SetLimit( uint64 m_cMicroSecDuration );
bool BLimitReached();
int64 CMicroSecOverage();
int64 CMicroSecLeft();
int64 CMilliSecLeft();
private:
int64 GetPerformanceCountNow();
int64 m_nPerformanceCounterStart;
int64 m_nPerformanceCounterEnd;
int64 m_nPerformanceCounterLimit;
static int64 sm_nPerformanceFrequency;
static bool sm_bUseQPC;
};
//-----------------------------------------------------------------------------
// Purpose: Records timer start time
//-----------------------------------------------------------------------------
inline void CReliableTimer::Start()
{
m_nPerformanceCounterStart = GetPerformanceCountNow();
}
//-----------------------------------------------------------------------------
// Purpose: Records timer end time
//-----------------------------------------------------------------------------
inline void CReliableTimer::End()
{
m_nPerformanceCounterEnd = GetPerformanceCountNow();
// enforce that we've advanced at least one cycle
if ( m_nPerformanceCounterEnd < m_nPerformanceCounterStart )
{
#ifdef _SERVER
if ( m_nPerformanceCounterEnd+10000 < m_nPerformanceCounterStart )
AssertMsgOnce( false, CDbgFmtMsg( "CReliableTimer went backwards - start:%lld end:%lld", m_nPerformanceCounterStart, m_nPerformanceCounterEnd ).ToString() );
#endif
m_nPerformanceCounterEnd = m_nPerformanceCounterStart + 1;
}
}
//-----------------------------------------------------------------------------
// Purpose: Gets microseconds elapsed between start and end
//-----------------------------------------------------------------------------
inline int64 CReliableTimer::GetMicroseconds()
{
DbgAssert( m_nPerformanceCounterStart ); // timer must have been started
DbgAssert( m_nPerformanceCounterEnd ); // timer must have been ended
DbgAssert( 0 != sm_nPerformanceFrequency ); // must have calc'd performance counter frequency
return ( ( m_nPerformanceCounterEnd - m_nPerformanceCounterStart ) * kMILLION / sm_nPerformanceFrequency );
}
//-----------------------------------------------------------------------------
// Purpose: Gets microseconds elapsed between start and end
//-----------------------------------------------------------------------------
inline int64 CReliableTimer::GetMilliseconds()
{
DbgAssert( m_nPerformanceCounterStart ); // timer must have been started
DbgAssert( m_nPerformanceCounterEnd ); // timer must have been ended
DbgAssert( 0 != sm_nPerformanceFrequency ); // must have calc'd performance counter frequency
return ( ( m_nPerformanceCounterEnd - m_nPerformanceCounterStart ) * kTHOUSAND / sm_nPerformanceFrequency );
}
//-----------------------------------------------------------------------------
// Purpose: Sets a limit on this timer that can subsequently be checked against
//-----------------------------------------------------------------------------
inline void CReliableTimer::SetLimit( uint64 cMicroSecDuration )
{
DbgAssert( 0 != sm_nPerformanceFrequency ); // must have calc'd performance counter frequency
m_nPerformanceCounterStart = GetPerformanceCountNow();
m_nPerformanceCounterLimit = m_nPerformanceCounterStart + ( ( cMicroSecDuration * sm_nPerformanceFrequency ) / kMILLION );
}
//-----------------------------------------------------------------------------
// Purpose: Returns if previously set limit has been reached
//-----------------------------------------------------------------------------
inline bool CReliableTimer::BLimitReached()
{
DbgAssert( m_nPerformanceCounterStart ); // SetLimit must have been called
DbgAssert( m_nPerformanceCounterLimit ); // SetLimit must have been called
int64 nPerformanceCountNow = GetPerformanceCountNow();
// make sure time advances
if ( nPerformanceCountNow < m_nPerformanceCounterStart )
{
#ifdef _SERVER
if ( nPerformanceCountNow+10000 < m_nPerformanceCounterStart )
AssertMsgOnce( false, CDbgFmtMsg( "CReliableTimer went backwards - start:%lld end:%lld", m_nPerformanceCounterStart, m_nPerformanceCounterEnd ).ToString() );
#endif
// reset the limit to be lower, to match our new clock
m_nPerformanceCounterLimit = nPerformanceCountNow + (m_nPerformanceCounterLimit - m_nPerformanceCounterStart);
}
return ( nPerformanceCountNow >= m_nPerformanceCounterLimit );
}
//-----------------------------------------------------------------------------
// Purpose: Returns microseconds current time is past limit, or 0 if not past limit
//-----------------------------------------------------------------------------
inline int64 CReliableTimer::CMicroSecOverage()
{
DbgAssert( m_nPerformanceCounterStart ); // SetLimit must have been called
DbgAssert( m_nPerformanceCounterLimit ); // SetLimit must have been called
int64 nPerformanceCountNow = GetPerformanceCountNow();
#ifdef _SERVER
if ( nPerformanceCountNow+10000 < m_nPerformanceCounterStart )
AssertMsgOnce( nPerformanceCountNow >= m_nPerformanceCounterStart, CDbgFmtMsg( "CReliableTimer went backwards - start:%lld end:%lld", m_nPerformanceCounterStart, m_nPerformanceCounterEnd ).ToString() );
#endif
int64 nPerformanceCountOver = ( nPerformanceCountNow > m_nPerformanceCounterLimit ?
nPerformanceCountNow - m_nPerformanceCounterLimit : 0 );
Assert( 0 != sm_nPerformanceFrequency ); // must have calc'd performance counter frequency
return ( nPerformanceCountOver * kMILLION / sm_nPerformanceFrequency );
}
//-----------------------------------------------------------------------------
// Purpose: Returns microseconds remaining until limit
//-----------------------------------------------------------------------------
inline int64 CReliableTimer::CMicroSecLeft()
{
DbgAssert( m_nPerformanceCounterStart ); // SetLimit must have been called
DbgAssert( m_nPerformanceCounterLimit ); // SetLimit must have been called
int64 nPerformanceCountNow = GetPerformanceCountNow();
#ifdef _SERVER
if ( nPerformanceCountNow+10000 < m_nPerformanceCounterStart )
AssertMsgOnce( nPerformanceCountNow >= m_nPerformanceCounterStart, CDbgFmtMsg( "CReliableTimer went backwards - start:%lld end:%lld", m_nPerformanceCounterStart, m_nPerformanceCounterEnd ).ToString() );
#endif
int64 nPerformanceCountLeft = ( nPerformanceCountNow < m_nPerformanceCounterLimit ?
m_nPerformanceCounterLimit - nPerformanceCountNow : 0 );
DbgAssert( 0 != sm_nPerformanceFrequency ); // must have calc'd performance counter frequency
return ( nPerformanceCountLeft * kMILLION / sm_nPerformanceFrequency );
}
//-----------------------------------------------------------------------------
// Purpose: Returns milliseconds remaining until limit
//-----------------------------------------------------------------------------
inline int64 CReliableTimer::CMilliSecLeft()
{
return CMicroSecLeft() / 1000;
}
#endif // TICKLIMITTIMER_H