Exception handling

Exception handling 的协作图:

结构体
struct	ExcInfo

类型定义
typedef VOID(*	EXC_PROC_FUNC) (UINT32, ExcContext *, UINT32, UINT32)
	Define an exception handling function hook. 更多...

函数
STATIC INLINE UINTPTR	Get_Fp (VOID)
	Kernel FP Register address obtain function. 更多...
UINT32	LOS_ExcRegHook (EXC_PROC_FUNC excHook)
	Register an exception handling hook. 更多...
NORETURN VOID	LOS_Panic (const CHAR *fmt,...)
	Kernel panic function. 更多...
VOID	LOS_RecordLR (UINTPTR *LR, UINT32 LRSize, UINT32 recordCount, UINT32 jumpCount)
	record LR function. 更多...
VOID	OsBackTrace (VOID)
	Kernel backtrace function. 更多...
VOID	OsTaskBackTrace (UINT32 taskID)
	Kernel task backtrace function. 更多...

详细描述

类型定义说明

EXC_PROC_FUNC

typedef VOID(* EXC_PROC_FUNC) (UINT32, ExcContext *, UINT32, UINT32)

Define an exception handling function hook.

Description:

This API is used to define the exception handling function hook based on the type of the exception handling function and record exceptions.

注意

None.

参数

None.

返回值

None.

Dependency:

los_exc.h: the header file that contains the API declaration.

参见

None.

在文件 los_exc.h 第 153 行定义.

函数说明

Get_Fp()

STATIC INLINE UINTPTR Get_Fp

(

VOID

)

Kernel FP Register address obtain function.

Description:

The API is used to obtain the FP Register address.

注意

None.

参数

None.

返回值

UINTPTR

The FP Register address.

Dependency:

los_exc.h: the header file that contains the API declaration.

参见

None.

在文件 los_exc.h 第 123 行定义.

{
    UINTPTR regFp;
 
#ifdef LOSCFG_ARCH_ARM_AARCH64
    __asm__ __volatile__("mov %0, X29" : "=r"(regFp));
#else
    __asm__ __volatile__("mov %0, fp" : "=r"(regFp));
#endif
 
    return regFp;
}

这是这个函数的调用关系图:

LOS_ExcRegHook()

UINT32 LOS_ExcRegHook

(

EXC_PROC_FUNC

excHook

)

Register an exception handling hook.

Description:

This API is used to register an exception handling hook.

注意

If the hook is registered for multiple times, the hook registered at the last time is effective.

The hook can be registered as NULL, indicating that the hook registration is canceled.

参数

excHook

[IN] Type EXC_PROC_FUNC: hook function.

返回值

#LOS_OK

The exception handling hook is successfully registered.

Dependency:

los_exc.h: the header file that contains the API declaration.

参见

None.

Register an exception handling hook.

在文件 los_exc.c 第 498 行定义.

{
    UINT32 intSave;
 
    intSave = LOS_IntLock();
    g_excHook = excHook;
    LOS_IntRestore(intSave);
 
    return LOS_OK;
}

函数调用图:

LOS_Panic()

NORETURN VOID LOS_Panic	(	const CHAR *	fmt,
			...
	)

Kernel panic function.

Description:

Stack function that prints kernel panics.

注意

After this function is called and stack information is printed, the system will fail to respond.

The input parameter can be NULL.

参数

fmt	[IN] Type CHAR* : variadic argument.

返回值

#None.

Dependency:

los_exc.h: the header file that contains the API declaration.

参见

None.

这是这个函数的调用关系图:

LOS_RecordLR()

VOID LOS_RecordLR	(	UINTPTR *	LR,
		UINT32	LRSize,
		UINT32	recordCount,
		UINT32	jumpCount
	)

record LR function.

Description:

注意

参数

LR	[IN] Type UINTPTR * LR buffer.
recordCount	[IN] Type UINT32 record LR lay number.
jumpCount	[IN] Type UINT32 ignore LR lay number.

返回值

#None.

Dependency:

los_exc.h: the header file that contains the API declaration.

参见

None.

在文件 los_exc.c 第 1353 行定义.

{
    UINT32 count = 0;
    UINT32 index = 0;
    UINT32 stackStart, stackEnd;
    LosTaskCB *taskCB = NULL;
    UINTPTR framePtr, tmpFramePtr, linkReg;
 
    if (LR == NULL) {
        return;
    }
    /* if LR array is not enough,just record LRSize. */
    if (LRSize < recordCount) {
        recordCount = LRSize;
    }
 
    taskCB = OsCurrTaskGet();
    stackStart = taskCB->topOfStack;
    stackEnd = stackStart + taskCB->stackSize;
 
    framePtr = Get_Fp();
    while ((framePtr > stackStart) && (framePtr < stackEnd) && IS_ALIGNED(framePtr, sizeof(CHAR *))) {
        tmpFramePtr = framePtr;
#ifdef LOSCFG_COMPILER_CLANG_LLVM
        linkReg = *(UINTPTR *)(tmpFramePtr + sizeof(UINTPTR));
#else
        linkReg = *(UINTPTR *)framePtr;
#endif
        if (index >= jumpCount) {
            LR[count++] = linkReg;
            if (count == recordCount) {
                break;
            }
        }
        index++;
#ifdef LOSCFG_COMPILER_CLANG_LLVM
        framePtr = *(UINTPTR *)framePtr;
#else
        framePtr = *(UINTPTR *)(tmpFramePtr - sizeof(UINTPTR));
#endif
    }
 
    /* if linkReg is not enough,clean up the last of the effective LR as the end. */
    if (count < recordCount) {
        LR[count] = 0;
    }
}

函数调用图:

这是这个函数的调用关系图:

OsBackTrace()

VOID OsBackTrace

(

VOID

)

Kernel backtrace function.

Description:

Backtrace function that prints task call stack information traced from the running task.

注意

None.

参数

None.

返回值

#None.

Dependency:

los_exc.h: the header file that contains the API declaration.

参见

None.

在文件 los_exc.c 第 1025 行定义.

{
    UINT32 regFP = Get_Fp();
    LosTaskCB *runTask = OsCurrTaskGet();
    PrintExcInfo("OsBackTrace fp = 0x%x\n", regFP);
    PrintExcInfo("runTask->taskName = %s\n", runTask->taskName);
    PrintExcInfo("runTask->taskID = %u\n", runTask->taskID);
    BackTrace(regFP);
}

函数调用图:

这是这个函数的调用关系图:

OsTaskBackTrace()

VOID OsTaskBackTrace

(

UINT32

taskID

)

Kernel task backtrace function.

Description:

Backtrace function that prints task call stack information traced from the input task.

注意

• The input taskID should be valid.

参数

taskID

[IN] Type UINT32 Task ID.

返回值

#None.

Dependency:

los_exc.h: the header file that contains the API declaration.

参见

None.

在文件 los_exc.c 第 1007 行定义.

{
    LosTaskCB *taskCB = NULL;
 
    if (OS_TID_CHECK_INVALID(taskID)) {
        PRINT_ERR("\r\nTask ID is invalid!\n");
        return;
    }
    taskCB = OS_TCB_FROM_TID(taskID);
    if (OsTaskIsUnused(taskCB) || (taskCB->taskEntry == NULL)) {
        PRINT_ERR("\r\nThe task is not created!\n");
        return;
    }
    PRINTK("TaskName = %s\n", taskCB->taskName);
    PRINTK("TaskID = 0x%x\n", taskCB->taskID);
    BackTrace(((TaskContext *)(taskCB->stackPointer))->R11); /* R11 : FP */
}

函数调用图: