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use critical section for improved performance

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This commit is contained in:
Jeff Hill
2001-03-08 22:04:37 +00:00
parent 963b610948
commit 26a35b488f
1 changed files with 27 additions and 80 deletions
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src/libCom/osi/os/WIN32/osdTime.cpp
+27 -80
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@@ -34,6 +34,7 @@
#include "epicsTime.h"
#include "errlog.h"
#include "epicsAssert.h"
#include "epicsThread.h"
//
// performance counter last value, ticks per sec,
@@ -60,21 +61,22 @@ static const SYSTEMTIME epicsEpochST = {
0 // milli sec
};
static bool osdTimeInitSuccess = false;
static epicsThreadOnceId osdTimeOnceFlag = EPICS_THREAD_ONCE_INIT;
static const LONGLONG FILE_TIME_TICKS_PER_SEC = 10000000L;
static HANDLE osdTimeMutex = NULL;
static CRITICAL_SECTION osdTimeCriticalSection;
static bool osdTimeSyncThreadExit = false;
static LONGLONG epicsEpoch;
static int osdTimeSych ();
/*
* osdTimeExit ()
*/
static void osdTimeExit ()
{
if ( osdTimeMutex ) {
CloseHandle (osdTimeMutex);
}
DeleteCriticalSection ( & osdTimeCriticalSection );
osdTimeSyncThreadExit = true;
}
@@ -99,7 +101,7 @@ static unsigned __stdcall osdTimeSynchThreadEntry (LPVOID)
//
// osdTimeInit ()
//
static void osdTimeInit ()
static void osdTimeInit ( void * )
{
LARGE_INTEGER parm;
BOOL success;
@@ -107,40 +109,8 @@ static void osdTimeInit ()
HANDLE osdTimeThread;
unsigned threadAddr;
FILETIME epicsEpochFT;
DWORD status;
if ( osdTimeMutex ) {
/* wait for init to complete */
status = WaitForSingleObject ( osdTimeMutex, INFINITE );
assert ( status == WAIT_OBJECT_0 );
success = ReleaseMutex ( osdTimeMutex );
assert (success);
return;
}
else {
HANDLE osdTimeMutexTmp;
osdTimeMutexTmp = CreateMutex (NULL, TRUE, NULL);
if ( osdTimeMutexTmp == 0 ) {
return;
}
#if 1
/* not arch neutral, but at least supported by w95 and borland */
if ( InterlockedExchange ( (LPLONG) &osdTimeMutex, (LONG) osdTimeMutexTmp ) ) {
#else
/* not supported on W95, but the alternative requires assuming that pointer and integer are the same */
if (InterlockedCompareExchange ( (PVOID *) &osdTimeMutex, (PVOID) osdTimeMutexTmp, (PVOID)0 ) != 0) {
#endif
CloseHandle (osdTimeMutexTmp);
/* wait for init to complete */
status = WaitForSingleObject (osdTimeMutex, INFINITE);
assert ( status == WAIT_OBJECT_0 );
success = ReleaseMutex (osdTimeMutex);
assert (success);
return;
}
}
InitializeCriticalSection ( & osdTimeCriticalSection );
//
// initialize elapsed time counters
@@ -149,8 +119,7 @@ static void osdTimeInit ()
// counters (Intel and Mips processors do)
//
if ( QueryPerformanceFrequency (&parm) == 0 ) {
CloseHandle (osdTimeMutex);
osdTimeMutex = NULL;
DeleteCriticalSection ( & osdTimeCriticalSection );
return;
}
perf_freq = parm.QuadPart;
@@ -160,20 +129,19 @@ static void osdTimeInit ()
//
success = SystemTimeToFileTime (&epicsEpochST, &epicsEpochFT);
if ( ! success ) {
CloseHandle ( osdTimeMutex );
osdTimeMutex = NULL;
DeleteCriticalSection ( & osdTimeCriticalSection );
return;
}
parm.LowPart = epicsEpochFT.dwLowDateTime;
parm.HighPart = epicsEpochFT.dwHighDateTime;
epicsEpoch = parm.QuadPart;
ReleaseMutex ( osdTimeMutex );
// set here to avoid recursion problems
osdTimeInitSuccess = true;
unixStyleStatus = osdTimeSych ();
if ( unixStyleStatus != epicsTimeOK ) {
CloseHandle ( osdTimeMutex );
osdTimeMutex = NULL;
DeleteCriticalSection ( & osdTimeCriticalSection );
return;
}
@@ -190,6 +158,7 @@ static void osdTimeInit ()
}
atexit ( osdTimeExit );
}
//
@@ -203,18 +172,9 @@ static int osdTimeSych ()
LONGLONG secondsSinceBoot;
FILETIME currentTimeFT;
LONGLONG currentTime;
BOOL win32Stat;
DWORD win32SemStat;
if (!osdTimeMutex) {
osdTimeInit ();
if (!osdTimeMutex) {
return epicsTimeERROR;
}
}
win32SemStat = WaitForSingleObject (osdTimeMutex, tmoTwentySec);
if ( win32SemStat != WAIT_OBJECT_0 ) {
epicsThreadOnce ( &osdTimeOnceFlag, osdTimeInit, 0 );
if ( ! osdTimeInitSuccess ) {
return epicsTimeERROR;
}
@@ -226,10 +186,11 @@ static int osdTimeSych ()
GetSystemTimeAsFileTime (&currentTimeFT);
// this one is second because QueryPerformanceFrequency()
// has forced its code to load
if (QueryPerformanceCounter (&parm)==0) {
ReleaseMutex (osdTimeMutex);
return epicsTimeERROR;
if ( QueryPerformanceCounter ( & parm ) == 0 ) {
return epicsTimeERROR;
}
EnterCriticalSection ( & osdTimeCriticalSection );
perf_last = parm.QuadPart;
parm.LowPart = currentTimeFT.dwLowDateTime;
@@ -311,10 +272,7 @@ static int osdTimeSych ()
perf_sec_offset = new_sec_offset;
perf_frac_offset = new_frac_offset;
win32Stat = ReleaseMutex (osdTimeMutex);
if (!win32Stat) {
return epicsTimeERROR;
}
LeaveCriticalSection ( & osdTimeCriticalSection );
return epicsTimeOK;
}
@@ -329,21 +287,13 @@ extern "C" epicsShareFunc int epicsShareAPI epicsTimeGetCurrent (epicsTimeStamp
LARGE_INTEGER parm;
BOOL status;
//
// lazy init
//
if (!osdTimeMutex) {
osdTimeInit ();
if (!osdTimeMutex) {
return epicsTimeERROR;
}
}
status = WaitForSingleObject (osdTimeMutex, tmoTwentySec);
if ( status != WAIT_OBJECT_0 ) {
epicsThreadOnce ( &osdTimeOnceFlag, osdTimeInit, 0 );
if ( ! osdTimeInitSuccess ) {
return epicsTimeERROR;
}
EnterCriticalSection ( & osdTimeCriticalSection );
//
// dont need to check status since it was checked once
// during initialization to see if the CPU has HR
@@ -351,7 +301,7 @@ extern "C" epicsShareFunc int epicsShareAPI epicsTimeGetCurrent (epicsTimeStamp
//
status = QueryPerformanceCounter (&parm);
if (!status) {
ReleaseMutex (osdTimeMutex);
LeaveCriticalSection ( & osdTimeCriticalSection );
return epicsTimeERROR;
}
time_cur = parm.QuadPart;
@@ -391,10 +341,7 @@ extern "C" epicsShareFunc int epicsShareAPI epicsTimeGetCurrent (epicsTimeStamp
pDest->secPastEpoch = (unsigned long) (time_sec%ULONG_MAX);
pDest->nsec = (unsigned long) ((time_remainder*epicsTime::nSecPerSec)/perf_freq);
status = ReleaseMutex (osdTimeMutex);
if (!status) {
return epicsTimeERROR;
}
LeaveCriticalSection ( & osdTimeCriticalSection );
return epicsTimeOK;
}