[Disksim-users] Crash at ioqueue_remove_from_subqueue

[Bhushan]

Thanks Ji-Yong and Yinliang.
I too had the same problem as Ji-Yang and adding unique opid to solved the
problem.

But I was wondering if this is the right fix or if it is some kind of
hack.My guess is the function ioqueue_request_match() should be changed to
find the correct match. I am trying to fix this function. Incase anyone has
done this exercise before or if adding unique opid is the correct solution
to this problem, please let me know.

Thanks again!

On Mon, Feb 23, 2009 at 1:35 AM, Ji-Yong Shin <shin.jiyong at gmail.com> wrote:

> Hi,
> I had the same problem. The reason for this is addtoextraq function doesn't
> reinitialize the iobuf or ioreq_event that are added to the extraq. Thus,
> when ioqueue is trying to remove a iobuf or ioreq_event with the same opid
> and blkno with the iobuf or ioreq_event that has been recently added to the
> extraq and is still pointed by a pointer in the ioqueue, it will make the
> error you described.
>
> One of the solutions I used was to make all the opid of ioreq_events unique
> so that even if the extraq doesn't reinitialize the iobuf or
> ioreq_event added to the extraq, the ioqueue functions will not mistakenly
> follow the path that leads to the error.
>
>
> On 2/23/09, Bhushan <mohan at cs.virginia.edu> wrote:
>
>> Hi,
>> Disksim crashes at ioqueue_remove_from_subqueue() when used along with ssd
>> add-on. This function removes tmp from the queue and resets the pointer in
>> the double linked list. But tmp->prev is NULL because of which disksim
>> crashes at tmp->prev->next. while accessing tmp->prev. Also, tmp->prev is
>> NULL for the entire tmp list.
>>
>> Can someone provide the guidelines as to when we should be calling
>> ioqueue_insert_new_request() and when we should be calling
>> ioqueue_remove_from_subqueue() assuming that the requests are serviced in
>> FCFS. In this way, I can find out if I am incorrectly calling any of the two
>> functions mentioned above.
>>
>> Thanks!
>>
>> --
>> Regards,
>> Bhushan.
>>
>> _______________________________________________
>> Disksim-users mailing list
>> Disksim-users at ece.cmu.edu
>> https://sos.ece.cmu.edu/mailman/listinfo/disksim-users
>>
>>
>
>
> --
> =======================
> Ji-Yong Shin
> Email: shin.jiyong at gmail.com
> =======================
>



-- 
Regards,
Bhushan.
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