Re: [patch 3/3] S390-HWBKPT v3: Modify ptrace to use Hardware Breakpoint interfaces.

[Frederic Weisbecker <fweisbec@gmail.com>]

On Thu, Jan 21, 2010 at 12:28:39PM +0530, Mahesh Jagannath Salgaonkar wrote:
> Heiko Carstens wrote:
>> On Thu, Jan 14, 2010 at 11:58:59AM +0530, Mahesh Salgaonkar wrote:
>>> Modify the ptrace code to use the hardware breakpoint interfaces for
>>> user-space
>>
>> I didn't look too deep into this one. So actually only one trivial comment:
>>
>>> diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
>>> index 9a1d276..cb74f24 100644
>>> --- a/include/linux/perf_event.h
>>> +++ b/include/linux/perf_event.h
>>> @@ -215,7 +215,11 @@ struct perf_event_attr {
>>>
>>>  	__u64			bp_addr;
>>>  	__u32			bp_type;
>>> +#ifdef __s390x__
>>> +	__u64			bp_len;
>>> +#else
>>>  	__u32			bp_len;
>>> +#endif
>>>  };
>>>
>>>  /*
>>>
>>
>> Any chance to change common code to change that to an __u64 (unconditional)
>> or at least an unsigned long?
>> I'd hate to see an ifdef __s390x__ in common code.
>
> Can we have the above common code to change the type of 'bp_len' to  
> __u64? In s390x arch watch point length can be upto 2^64.



Yep, please send a patch to make it a generic u64 if an arch needs it.
We really need a fixed cross arch size for this structure.

Thanks!