Re: [PATCH -tip ] [BUGFIX] perf/probe: Fix perf probe to find correct variable DIE

Masami Hiramatsu
2014-06-04T12:20:06Z

(2014/06/04 20:31), Jiri Olsa wrote:
> On Wed, Jun 04, 2014 at 05:25:02PM +0900, Masami Hiramatsu wrote:
>> (2014/06/04 5:38), Arnaldo Carvalho de Melo wrote:
>>> Now trying to reference a bogus member name:
>>>
>>> [root@zoo ~]# perf probe 'vfs_getname=getname_flags:65 pathname=result->BOGUS:string'
>>> result(type:filename) has no member BOGUS.
>>> Failed to find 'result' in this function.
>>> Error: Failed to add events. (-22)
>>> [root@zoo ~]#
>>>
>>> No segfault, albeit it produces a bogus error message, as it clearly
>>> _finds_ the 'result' variable, its just that it is of a struct type that
>>> _has_ no such 'BOGUS' _member_.
>>
>> Right, I'll fix that.
>
> should I wait for new patchset, or should I take those 2?

No, those 2 patches are urgently required, because one fixes SEGV critical
error, and the other fixes a wrong behavior (catch up to the latest
dwarf), which is also degradation.
I think changing error messages is a kind of usability enhancement.

Thank you,

--
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Research Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com