RTOS/TM4C1294NCPDT: TM4C1294NCPDT

Ramesh Muruganantham

Expert 1410 points

Part Number: TM4C1294NCPDT
Other Parts Discussed in Thread: SYSBIOS

Tool/software: TI-RTOS

I am developing a project using TiRtos. In that I am using Queue. In runtime the code crash at Queue_dequeue().

I did the implementation as follows( copying and pasting only queue related code)

typedef struct XmitMsgQ {
Queue_Elem elem;
Char Xmsgbuf[30];
} xmitq;

struct XmitMsgQ Xmsg;

Queue_Handle XmitMsgQHandle;

XmitMsgQHandle=Queue_create(NULL, NULL);

Queue_enqueue(XmitMsgQHandle, &(Xmsg.elem));

    xmitq* XmsginQ;
   if(!Queue_empty(XmitMsgQHandle))
    XmsginQ= Queue_dequeue(XmitMsgQHandle);

The code crashes at XmsginQ= Queue_dequeue(XmitMsgQHandle);

The crash message below:

ti.sysbios.family.arm.m3.Hwi: line 1087: E_hardFault: FORCED
ti.sysbios.family.arm.m3.Hwi: line 1164: E_busFault: IMPRECISERR: Delayed Bus Fault, exact addr unknown, address: e000ed38
Exception occurred in background thread at PC = 0x00012d66.
Core 0: Exception occurred in ThreadType_Task.
Task name: {unknown-instance-name}, handle: 0x20001270.
Task stack base: 0x200012c0.
Task stack size: 0x400.
R0 = 0x2000fc94 R8 = 0xffffffff
R1 = 0x200008d8 R9 = 0xffffffff
R2 = 0x00015a04 R10 = 0xffffffff
R3 = 0x00000009 R11 = 0xffffffff
R4 = 0xffffffff R12 = 0x153d0200
R5 = 0xffffffff SP(R13) = 0x200014f8
R6 = 0xffffffff LR(R14) = 0x00012d63
R7 = 0xffffffff PC(R15) = 0x00012d66
PSR = 0x81000000
ICSR = 0x00423803
MMFSR = 0x00
BFSR = 0x04
UFSR = 0x0000
HFSR = 0x40000000
DFSR = 0x0000000b
MMAR = 0xe000ed34
BFAR = 0xe000ed38
AFSR = 0x00000000
Terminating execution...

Appreciate your help

over 6 years ago

0 ToddMullanix over 6 years ago

TI__Guru* 96960 points

Hi Ramesh,

Take a look at this training on exceptions: training.ti.com/debugging-common-application-issues-ti-rtos

Can you step through the code to get the exact spot in Queue_dequeue?

Please note that Queue_dequeue/enqueue are not thread-safe (in case another thread is acting on the same queue). Queue_get/put are the thread-safe versions of the APIs.

Todd

0 ToddMullanix over 6 years ago in reply to ToddMullanix

TI__Guru* 96960 points

Hi Ramesh,

Did this get resolved?

Todd

0 Ramesh Muruganantham over 6 years ago in reply to ToddMullanix

Expert 1410 points

In travel this week and could not check. Will check next week and let you know.

Thanks & Regards,
Ramesh

0 ToddMullanix over 6 years ago in reply to Ramesh Muruganantham

TI__Guru* 96960 points

Sounds good.

0 ToddMullanix over 6 years ago in reply to ToddMullanix

TI__Guru* 96960 points

Any update?

0 Ramesh Muruganantham over 6 years ago in reply to ToddMullanix

Expert 1410 points

Sorry. I am still on travel. Will check next week.

Regards,
Ramesh

0 ToddMullanix over 6 years ago in reply to Ramesh Muruganantham

TI__Guru* 96960 points

No problem. Safe trip!

0 Ramesh Muruganantham over 6 years ago in reply to ToddMullanix

Expert 1410 points

Dear Todd,

I had some time today to check this again. I stepped through the code and it crashed at this point in file Hwi_asm.sv7M at line #221.

pop {r0} ; retrieve old basepri

; CAUTION!!! Do NOT single step thru the next instruction
; else, the processor won't arrive at pendSV thru the
; exception mechanism.

msr basepri, r0 ; causes pendSV to happen
nop ; 2 nops required for prefetch
nop ;

I gone through the presentation . However could not solve the problem.

Regards,
Ramesh

0 ToddMullanix over 6 years ago in reply to Ramesh Muruganantham

TI__Guru* 96960 points

Ramesh,

As the comment states, you cannot single step through this code.

Todd

0 Ramesh Muruganantham over 6 years ago in reply to ToddMullanix

Expert 1410 points

Todd,
Any other ways to debug? Can we get some clue from the crash logs?

Regards,
Ramesh

0 ToddMullanix over 6 years ago in reply to Ramesh Muruganantham

TI__Guru* 96960 points

What did ROV show in the Hwi->Exceptions tab? Was there a callstack? From your first post, it looks like you know the think it is in Queue_dequeue. Can you wrap that function with a Hwi_disable/Hwi_restore? Does the problem still happen?

0 ToddMullanix over 6 years ago in reply to ToddMullanix

TI__Guru* 96960 points

Any updates?

[4/25 Update: Marking this as TI Thinks Resolved due to no activity from original poster.]

0 Ramesh Muruganantham over 6 years ago in reply to ToddMullanix

Expert 1410 points

Sorry. I missed your message.

I checked and still the crash occurs.

The code as follows

xmitq* XmsginQ;
UInt key;
if(!Queue_empty(XmitMsgQHandle))
{
key= Hwi_disable();
XmsginQ= Queue_dequeue(XmitMsgQHandle);
Hwi_restore(key);
}

Crash logs from console:

ti.sysbios.family.arm.m3.Hwi: line 1087: E_hardFault: FORCED
ti.sysbios.family.arm.m3.Hwi: line 1164: E_busFault: IMPRECISERR: Delayed Bus Fault, exact addr unknown, address: e000ed38
Exception occurred in background thread at PC = 0x0001199a.
Core 0: Exception occurred in ThreadType_Task.
Task name: {unknown-instance-name}, handle: 0x20001270.
Task stack base: 0x200012c0.
Task stack size: 0x400.
R0 = 0x00000000 R8 = 0xffffffff
R1 = 0x200008d8 R9 = 0xffffffff
R2 = 0x00015a1c R10 = 0xffffffff
R3 = 0x00000009 R11 = 0xffffffff
R4 = 0xffffffff R12 = 0x153d0200
R5 = 0xffffffff SP(R13) = 0x200014f0
R6 = 0xffffffff LR(R14) = 0x00011997
R7 = 0xffffffff PC(R15) = 0x0001199a
PSR = 0x01000000
ICSR = 0x00423803
MMFSR = 0x00
BFSR = 0x04
UFSR = 0x0000
HFSR = 0x40000000
DFSR = 0x0000000b
MMAR = 0xe000ed34
BFAR = 0xe000ed38
AFSR = 0x00000000
Terminating execution..

0 ToddMullanix over 6 years ago in reply to Ramesh Muruganantham

TI__Guru* 96960 points

Can you use Queue_get and Queue_put instead of Queue_enqueue and Queue_dequeue? I want to rule out any thread-safety issues.

Todd

0 Ramesh Muruganantham over 6 years ago in reply to ToddMullanix

Expert 1410 points

Tried with Queue_get and Queue_put and same issue

ti.sysbios.family.arm.m3.Hwi: line 1087: E_hardFault: FORCED
ti.sysbios.family.arm.m3.Hwi: line 1164: E_busFault: IMPRECISERR: Delayed Bus Fault, exact addr unknown, address: e000ed38
Exception occurred in background thread at PC = 0x000124be.
Core 0: Exception occurred in ThreadType_Task.
Task name: {unknown-instance-name}, handle: 0x20001270.
Task stack base: 0x200012c0.
Task stack size: 0x400.
R0 = 0x20010410 R8 = 0xffffffff
R1 = 0x200008d8 R9 = 0xffffffff
R2 = 0x00015a34 R10 = 0xffffffff
R3 = 0x00000000 R11 = 0xffffffff
R4 = 0xffffffff R12 = 0x153d0200
R5 = 0xffffffff SP(R13) = 0x200014f8
R6 = 0xffffffff LR(R14) = 0x000124bd
R7 = 0xffffffff PC(R15) = 0x000124be
PSR = 0x01000000
ICSR = 0x00423803
MMFSR = 0x00
BFSR = 0x04
UFSR = 0x0000
HFSR = 0x40000000
DFSR = 0x0000000b
MMAR = 0xe000ed34
BFAR = 0xe000ed38
AFSR = 0x00000000
Terminating execution...

0 ToddMullanix over 6 years ago in reply to Ramesh Muruganantham

TI__Guru* 96960 points

Ok. Thanks for ruling that out.

It seems like you should be able to debug this. You know it's occurring in a task.

Ramesh Muruganantham said:
Core 0: Exception occurred in ThreadType_Task.

You can look in ROV to see which task it is

Ramesh Muruganantham said:
Task name: {unknown-instance-name}, handle: 0x20001270.

If it is occurring in the Queue API call, look at the prev and next fields to see if they make sense. If they are pointing somewhere wrong, you need to debug where the corruption occurred.

Todd

0 Ramesh Muruganantham over 6 years ago in reply to ToddMullanix

Expert 1410 points

Thanks Todd. This is the first time I am using the Ti RTOS. I will get myself familiar with ROV and then check this and get back to you asap.

Regards,
Ramesh

0 ToddMullanix over 6 years ago in reply to Ramesh Muruganantham

TI__Guru* 96960 points

Sounds good

0 ToddMullanix over 6 years ago in reply to ToddMullanix

TI__Guru* 96960 points

Any updates?

0 Ramesh Muruganantham over 6 years ago in reply to ToddMullanix

Expert 1410 points

I found the issue.

I have declared struct XmitMsgQ Xmsg; inside a function and passed the address to the Queue_put api function.
Queue_put(XmitMsgQHandle, &(Xmsg.elem) );

Since the memory is temporary inside the function , while retrieving the same using Queue_get it is crashing. Now I declared as global and the crash is not happening.

Thank you very much for the support

Regards,
Ramesh

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RTOS/TM4C1294NCPDT: TM4C1294NCPDT