Leaked source code of windows server 2003
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393 lines
7.6 KiB

/*++
Copyright (c) 1994 Microsoft Corporation
All rights reserved.
Module Name:
State.cxx
Abstract:
State abstraction and critical section
Author:
Albert Ting (AlbertT) 28-May-1994
Revision History:
--*/
#include "spllibp.hxx"
#pragma hdrstop
#if DBG
MCritSec* MRefCom::gpcsCom;
#endif
/********************************************************************
Ref counting
********************************************************************/
VOID
MRefQuick::
vIncRef(
VOID
)
{
#if DBG
LONG cRefOld = _cRef;
_BackTrace.hCapture( cRefOld, cRefOld + 1 );
#endif
++_cRef;
}
LONG
MRefQuick::
cDecRef(
VOID
)
{
#if DBG
LONG cRefOld = _cRef;
_BackTrace.hCapture( cRefOld, cRefOld - 1 );
#endif
--_cRef;
if( !_cRef ){
vRefZeroed();
return 0;
}
return _cRef;
}
VOID
MRefQuick::
vDecRefDelete(
VOID
)
{
#if DBG
LONG cRefOld = _cRef;
_BackTrace.hCapture( cRefOld, cRefOld );
#endif
--_cRef;
if( !_cRef ){
vRefZeroed();
}
}
/********************************************************************
MRefCom: Reference counting using interlocked references.
This avoids creating a common critical section.
vDeleteDecRef is the same as vDecRef, but it logs differently.
********************************************************************/
VOID
MRefCom::
vIncRef(
VOID
)
{
#if DBG
gpcsCom->vEnter();
LONG cRefOld = _cRef;
gpcsCom->vLeave();
_BackTrace.hCapture( cRefOld, cRefOld+1 );
#endif
InterlockedIncrement( &_cRef );
}
LONG
MRefCom::
cDecRef(
VOID
)
{
#if DBG
gpcsCom->vEnter();
LONG cRefOld = _cRef;
gpcsCom->vLeave();
_BackTrace.hCapture( cRefOld, cRefOld - 1 );
#endif
LONG cRefReturn = InterlockedDecrement( &_cRef );
if( !cRefReturn ){
vRefZeroed();
}
return cRefReturn;
}
VOID
MRefCom::
vDecRefDelete(
VOID
)
{
#if DBG
gpcsCom->vEnter();
LONG cRefOld = _cRef;
gpcsCom->vLeave();
_BackTrace.hCapture( cRefOld, cRefOld );
#endif
if( !InterlockedDecrement( &_cRef )){
vRefZeroed();
}
}
VOID
MRefCom::
vRefZeroed(
VOID
)
{
}
/********************************************************************
Critical section implementation
Logging:
CS initialized: 00000000 00000000 00000000
CS acquired: 1eeeeeee bbbbbbbb tttttttt
e New entry count.
b TickCount thread was blocked before acquiring CS.
t Total tickcount all threads have blocked before acquiring CS
CS released: 0eeeeeee iiiiiiii tttttttt
e New entry count.
i Time spent inside the CS, from _first_ acquisition.
t Total tickcount all threads inside CS.
********************************************************************/
#if DBG
MCritSec::
MCritSec(
VOID
) : _dwThreadOwner( 0 ), _dwEntryCount( 0 ),
_dwTickCountBlockedTotal( 0 ), _dwTickCountInsideTotal( 0 ),
_dwEntryCountTotal( 0 )
{
InitializeCriticalSectionAndSpinCount( &_CritSec, 0x80000000 );
_BackTrace.hCapture( 0, 0, 0 );
}
MCritSec::
~MCritSec(
VOID
)
{
DeleteCriticalSection( &_CritSec );
}
VOID
MCritSec::
vEnter(
VOID
)
{
DWORD dwTickCountBefore = GetTickCount();
EnterCriticalSection( &_CritSec );
++_dwEntryCountTotal;
DWORD dwTickCountBlocked = 0;
//
// Re-entrant case: only start the TickCountEntered counter
// if this is the first time we've entered the cs.
//
if( _dwEntryCount == 0 ){
//
// Check how long it took us to enter the critical section.
//
_dwTickCountEntered = GetTickCount();
dwTickCountBlocked = _dwTickCountEntered - dwTickCountBefore;
//
// Update the amount of time this thread blocked on this cs.
//
_dwTickCountBlockedTotal += dwTickCountBlocked;
}
//
// We have entered the critical section; update the count
// and the thread owner.
//
++_dwEntryCount;
_dwThreadOwner = GetCurrentThreadId();
_BackTrace.hCapture( 0x10000000 | _dwEntryCount,
dwTickCountBlocked,
_dwTickCountBlockedTotal );
}
VOID
MCritSec::
vLeave(
VOID
)
{
SPLASSERT( bInside( ));
DWORD dwTickCountInside = GetTickCount() - _dwTickCountEntered;
--_dwEntryCount;
//
// Verify that we don't leave a CritSecHardLock.
//
TIter Iter;
TCritSecHardLock *pCritSecHardLock;
for( CritSecHardLock_vIterInit( Iter ), Iter.vNext();
Iter.bValid();
Iter.vNext( )){
pCritSecHardLock = CritSecHardLock_pConvert( Iter );
//
// If you hit this assert, then you have created a hard
// lock, but someone is trying to leave it. See header file
// for more info (state.hxx).
//
if( _dwEntryCount < pCritSecHardLock->_dwEntryCountMarker ){
DBGMSG( DBG_ERROR, ( "CritSec.vLeave: Leaving a hard lock.\n" ));
}
}
//
// If this leave frees the critical section, then capture
// the total time the section was held (from the very first enter).
//
if( !_dwEntryCount ){
_dwTickCountInsideTotal += dwTickCountInside;
//
// Since we are leaving the critical section for the last
// time, the CS is now unowned. We set the thread owner to 0.
//
_dwThreadOwner = 0;
}
//
// Note: dwTickCountInsideTotal is based on _first_ entrance
// of critical section, not the most recent.
//
_BackTrace.hCapture( ~0x10000000 & _dwEntryCount,
dwTickCountInside,
_dwTickCountInsideTotal );
LeaveCriticalSection( &_CritSec );
}
BOOL
MCritSec::
bInside(
VOID
) const
{
if( !_dwEntryCount || GetCurrentThreadId() != _dwThreadOwner ){
DBGMSG( DBG_NONE, ( "CritSec: Not inside 0x%x!\n", this ));
return FALSE;
}
return TRUE;
}
BOOL
MCritSec::
bOutside(
VOID
) const
{
//
// We are outside if dwThreadOwner is not our thread id.
//
DWORD dwThreadOwner = (DWORD)InterlockedCompareExchange(
(PLONG)&_dwThreadOwner,
0,
0 );
if( dwThreadOwner == GetCurrentThreadId( )){
DBGMSG( DBG_NONE, ( "CritSec: Not outside 0x%x!\n",this ));
return FALSE;
}
return TRUE;
}
#else // !DBG
MCritSec::
MCritSec() {
InitializeCriticalSectionAndSpinCount(&_CritSec, 0);
}
#endif
/********************************************************************
TCritSecHardLock
********************************************************************/
#if DBG
TCritSecHardLock::
TCritSecHardLock(
MCritSec& CritSec
) : _CritSec( CritSec )
{
_CritSec.vEnter();
//
// Add ourselves to the linked list and remember what the entry
// count is. Everytime we leave the critical section, we'll look
// at all the items in the list and see if the current entry count
// is < all hard locks.
//
_CritSec.CritSecHardLock_vAdd( this );
_dwEntryCountMarker = _CritSec._dwEntryCount;
}
TCritSecHardLock::
~TCritSecHardLock(
VOID
)
{
CritSecHardLock_vDelinkSelf();
_CritSec.vLeave();
}
#endif