Re: Does perf support different length of user-space hw_breakpoint?

[xiakaixu]

ä 2014/5/13 23:06, Frederic Weisbecker åé:
> On Tue, May 13, 2014 at 02:00:46PM +0200, Jiri Olsa wrote:
>> On Mon, May 12, 2014 at 03:52:54PM +0800, xiakaixu wrote:
>>> Hi guys,
>>>
>>> Does perf support different length of user-space hw_breakpoint,
>>> such as  HW_BREAKPOINT_LEN_1/HW_BREAKPOINT_LEN_2/HW_BREAKPOINT_LEN_4/
>>> HW_BREAKPOINT_LEN_8?
>>>
>>> Seems perf only support HW_BREAKPOINT_LEN_4/sizeof(long)
>>> by default from the source code and simple test.
>>
>> right..
>>
>>         /*
>>          * We should find a nice way to override the access length
>>          * Provide some defaults for now
>>          */
>>         if (attr.bp_type == HW_BREAKPOINT_X)
>>                 attr.bp_len = sizeof(long);
>>         else
>>                 attr.bp_len = HW_BREAKPOINT_LEN_4;
>>
>>>
>>> May I have your opinions if I want to trace different bytes of
>>> hw_breakpoint addr?
>>
>> I guess that depends on what you want to do ;-)
> 
> Ah, I have a patchset from Jacob Shin and Suravee Suthikulpanit that does
> that. Also it has been hanging around for too long by my fault. I'm posting
> it now.

Thanks for your reply!
Hopefully I can get it ASAP.
> .
> 


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