void OSCtxSw(void)
{
asm("\
lea nextstart,%eax;\
push %eax;\
pushf;\
pusha;\
movl _OSTCBCur,%ebx;\
movl %esp,(%ebx);\
");
OSTaskSwHook();
OSTCBCur = OSTCBHighRdy;
OSPrioCur = OSPrioHighRdy;
asm("\
movl _OSTCBCur,%ebx;\
movl (%ebx),%esp;\
popa;\
popf;\
ret\
");
asm("nextstart:");
return;
}
void OSIntCtxSw (void)
{
OSTaskSwHook();
OSTCBCur = OSTCBHighRdy;
OSPrioCur = OSPrioHighRdy;
OSIntCtxRestore(OSTCBHighRdy->OSTCBStkPtr);
}
//OSStartHighRdy:让优先级最高的任务运行函数--------------------------------*
//功 能:让优先级最高的就绪态任务开始运行 *
//参 数:无 *
//返 回:无 *
//-------------------------------------------------------------------------*
void OSStartHighRdy(void)
{
OSTaskSwHook();
OSRunning = 1;
asm{
ldx OSTCBCur //将TCB的地址给X
lds 0,X //将值给SP
pula
staa $30 //恢复页面寄存器
nop //延时
rti
}
}
void OSStartHighRdy(void)
{
OSTaskSwHook();
OSRunning = TRUE;
asm("\
movl %eax,_OSRunning;\
movl _OSTCBCur,%ebx;\
movl (%ebx),%esp;\
popa;\
popf;\
ret\
");
}
//OSIntCtxSw:中断级任务切换函数--------------------------------------------*
//功 能:如果在中断服务结束时，中断中激活了更高优先级的任务，则调用该函数 *
//参 数:无 *
//返 回:无 *
//-------------------------------------------------------------------------*
void OSIntCtxSw(void)
{
OSTaskSwHook();
OSTCBCur = OSTCBHighRdy; //Change OSTCBCur and OSPrioCur
OSPrioCur = OSPrioHighRdy;
asm{
ldx OSTCBCur //get the new task's TCB's address
lds 0,x
pula
staa $30
nop //retore ppage from stack
rti
}
}
void OSCtxSw()
{
DWORD n = 0;
if(!(SS_SP->Exit)) {
n = SuspendThread(SS_SP->Handle);
}
OSTaskSwHook();
OSTrace( OBJ_SW, PT_SW_CTX, OSTCBHighRdy, 0, OSPrioCur, OSPrioHighRdy,0 );
OSTCBCur = OSTCBHighRdy;
OSPrioCur = OSPrioHighRdy;
SS_SP = (OS_EMU_STK*) OSTCBHighRdy->OSTCBStkPtr;
ResumeThread(SS_SP->Handle);
}
void OSIntCtxSw(void)
{
OS_STK *sp;
OSTaskSwHook();
sp = (OS_STK *)Context.Esp; //得到主线程当前堆栈指针
//在堆栈中保存相应寄存器。
*--sp = Context.Eip; //先保存eip
*--sp = Context.EFlags; //保存efl
*--sp = Context.Eax;
*--sp = Context.Ecx;
*--sp = Context.Edx;
*--sp = Context.Ebx;
*--sp = Context.Esp; //此时保存的esp是错误的，但OSTCBCur保存了正确的
*--sp = Context.Ebp;
*--sp = Context.Esi;
*--sp = Context.Edi;
OSTCBCur->OSTCBStkPtr = (OS_STK *)sp; //保存当前esp
OSTCBCur = OSTCBHighRdy; //得到当前就绪最高优先级任务的tcb
OSPrioCur = OSPrioHighRdy; //得到当前就绪任务最高优先级数
sp = OSTCBHighRdy->OSTCBStkPtr; //得到重新执行的任务的堆栈指针
//恢复所有处理器的寄存器
Context.Edi = *sp++;
Context.Esi = *sp++;
Context.Ebp = *sp++;
Context.Esp = *sp++; //此时上下文中得到的esp是不正确的
Context.Ebx = *sp++;
Context.Edx = *sp++;
Context.Ecx = *sp++;
Context.Eax = *sp++;
Context.EFlags = *sp++;
Context.Eip = *sp++;
Context.Esp = (unsigned long)sp; //得到正确的esp
SetThreadContext(mainhandle, &Context); //保存主线程上下文
}
void OSStartHighRdy (void)
{
OSTaskSwHook();
OSRunning = 1;
OSCtxRestore(OSTCBHighRdy->OSTCBStkPtr);
}
void OSStartHighRdy()
{
DWORD dwID;
OSInitTrace(100000);
OS_ENTER_CRITICAL();
OSTaskSwHook();
++OSRunning;
OSCtxSwW32Event = CreateEvent(NULL,FALSE,FALSE,NULL);
OSCtxSwW32Handle = CreateThread( NULL, 0, OSCtxSwW32, 0, 0, &dwID );
SetPriorityClass(OSCtxSwW32Handle,THREAD_PRIORITY_HIGHEST);
#ifdef SET_AFFINITY_MASK
if( SetThreadAffinityMask( OSCtxSwW32Handle, 1 ) == 0 ) {
#ifdef OS_CPU_TRACE
OS_Printf("Error: SetThreadAffinityMask\n");
#endif
}
#endif
SetThreadPriority(OSCtxSwW32Handle,THREAD_PRIORITY_TIME_CRITICAL);
OSTick32Handle = CreateThread( NULL, 0, OSTickW32, 0, 0, &dwID );
SetPriorityClass(OSTick32Handle,THREAD_PRIORITY_HIGHEST);
#ifdef SET_AFFINITY_MASK
if( SetThreadAffinityMask( OSTick32Handle, 1 ) == 0 )
{
#ifdef OS_CPU_TRACE
OS_Printf("Error: SetThreadAffinityMask\n");
#endif
}
#endif
SetThreadPriority(OSTick32Handle,THREAD_PRIORITY_HIGHEST);
#ifdef WIN_MM_TICK
timeGetDevCaps(&OSTimeCap, sizeof(OSTimeCap));
if( OSTimeCap.wPeriodMin < WIN_MM_MIN_RES )
OSTimeCap.wPeriodMin = WIN_MM_MIN_RES;
timeBeginPeriod(OSTimeCap.wPeriodMin);
OSTickEventHandle = CreateEvent(NULL, FALSE, FALSE, NULL);
OSTickTimer = timeSetEvent((1000/OS_TICKS_PER_SEC),OSTimeCap.wPeriodMin,(LPTIMECALLBACK)OSTickEventHandle, dwID,TIME_PERIODIC|TIME_CALLBACK_EVENT_SET);
#endif
SS_SP = (OS_EMU_STK*) OSTCBHighRdy->OSTCBStkPtr; /* OSTCBCur = OSTCBHighRdy; */
/* OSPrioCur = OSPrioHighRdy; */
ResumeThread(SS_SP->Handle);
OS_EXIT_CRITICAL();
WaitForSingleObject(OSCtxSwW32Handle,INFINITE);
#ifdef WIN_MM_TICK
timeKillEvent(OSTickTimer);
timeEndPeriod(OSTimeCap.wPeriodMin);
CloseHandle(OSTickEventHandle);
#endif
CloseHandle(OSTick32Handle);
CloseHandle(OSCtxSwW32Event);
}
// OSScheduleThread ***********************************************************
// Start tasks, triggered by hScheduleEvent
void OSScheduleThread(INT32U param)
{ char temp[256];
INT16S oldIndex, nextIndex;
#if OS_CRITICAL_METHOD == 3
OS_CPU_SR cpu_sr = TRUE;
#endif
DBGPRINT(0x00000001, "*** OSScheduleThread First Call\n");
while (1)
{ if (WaitForSingleObject(hScheduleEvent, OS_SCHEDULER_TIMEOUT) == WAIT_TIMEOUT) //Wait for a scheduler event (with timeout)
{ sprintf(temp, "ERROR: Scheduler timed out in OSScheduleThread %u --> %u IF=%u <-%u<%u<%u<%u<%u<%u<%u<%u<-\n",
OSPrioCur, OSPrioHighRdy, virtualInterruptFlag,
taskLog[0], taskLog[1], taskLog[2], taskLog[3],
taskLog[4], taskLog[5], taskLog[6], taskLog[7]
);
DBGPRINT(0x00000040, temp);
MessageBox(NULL, temp, "UCOS-II WIN32", MB_OK | MB_SETFOREGROUND | MB_ICONERROR); //In case of timeout, display an error message ...
OSRunning=0;
SetConsoleCtrlHandler((PHANDLER_ROUTINE) CtrlBreakHandler, FALSE);
return; //... and exit (will return to OSStartHighRdy())
}
OSTaskSwHook(); //Call the task switch hook function
EnterCriticalSection(&criticalSection);
if (taskSuspended[OSPrioCur]==-1)
{ DBGPRINT(0x00000001, "Old Task %d marked for deletion - %X - %X\n", OSPrioCur, hTaskThread[OSPrioCur], OSTCBCur);
SuspendThread(hTaskThread[OSPrioCur]);
ExecuteDeleteTask(OSPrioCur);
oldIndex = OSPrioCur;
} else
{ oldIndex = GetThreadIndexForTask(OSTCBCur);
}
nextIndex= GetThreadIndexForTask(OSTCBHighRdy);
if (oldIndex==-1 || nextIndex==-1)
{ printf("ERROR: Internal scheduling error: oldIndex=%d - %d nextIndex=%d - %d\n",oldIndex, OSTCBCur->OSTCBPrio, nextIndex, OSTCBHighRdy->OSTCBPrio);
exit(-1);
}
OSTCBCur = OSTCBHighRdy; //Now logically switch to the new task
OSPrioCur = (INT8U) nextIndex;
idleTrigger = TRUE;
DBGPRINT(0x00000001, "*** OSScheduleThread from %2u to %2u\n", oldIndex, nextIndex);
if (OSTCBPrioTbl[oldIndex] == NULL) //If a task has been deleted
{ if (hTaskThread[oldIndex]) //... remove it, normally this should never happen
{ if (TerminateThread(hTaskThread[oldIndex], 0)==FALSE)
{ printf("ERROR: Terminate thread for task %d (in OSScheduleThread) WIN32 error code: %Xh\n", oldIndex, GetLastError());
}
CloseHandle(hTaskThread[oldIndex]);
}
hTaskThread[oldIndex] = NULL;
taskSuspended[oldIndex]=0;
} else
if (oldIndex != nextIndex && taskSuspended[oldIndex]==0) //If switching context to a new task ...
{ if (SuspendThread(hTaskThread[oldIndex])!=0) //... suspend the thread associated with the current task
printf("ERROR: SuspendThread() (in OSSCheduleThread) failed with error %Xh - task %d - %d\n", GetLastError(), oldIndex, taskSuspended[oldIndex]);
taskSuspended[oldIndex]++; //(update suspend counter to avoid multiple suspends of the same task)
}
if (taskSuspended[nextIndex]>0)
{ taskSuspended[nextIndex]--; //(updates suspend counter to avoid multiple resumes of the same task)
if (taskSuspended[nextIndex] < 0)
taskSuspended[nextIndex]=0;
if (virtualInterruptFlag==FALSE)
#if OS_CRITICAL_METHOD == 3
OSEnableInterruptFlag(&cpu_sr);
#else
OSEnableInterruptFlag();
#endif
OSLog(nextIndex);
if (ResumeThread(hTaskThread[nextIndex])!=1) //... and resume the thread associated with the new task
printf("ERROR: ResumeThread() (in OSSCheduleThread) failed with error %Xh\n", GetLastError());
} else
{ if (virtualInterruptFlag==FALSE)
#if OS_CRITICAL_METHOD == 3
OSEnableInterruptFlag(&cpu_sr);
#else
OSEnableInterruptFlag();
#endif
}
LeaveCriticalSection(&criticalSection);
}
}
