[PATCH 7/8] perf probe: Improve detection of file/function name in the probe pattern

Tim Gardner tim.gardner at canonical.com
Tue Sep 15 16:05:49 UTC 2015


On 09/15/2015 02:03 AM, Stefan Bader wrote:
> On 11.09.2015 16:42, tim.gardner at canonical.com wrote:
>> From: "Naveen N. Rao" <naveen.n.rao at linux.vnet.ibm.com>
>>
>> BugLink: http://bugs.launchpad.net/bugs/1485528
>>
>> Currently, perf probe considers patterns including a '.' to be a file.
>> However, this causes problems on powerpc ABIv1 where all functions have
>> a leading '.':
>>
>>    $ perf probe -F | grep schedule_timeout_interruptible
>>    .schedule_timeout_interruptible
>>    $ perf probe .schedule_timeout_interruptible
>>    Semantic error :File always requires line number or lazy pattern.
>>      Error: Command Parse Error.
>>
>> Fix this:
>> - by checking the probe pattern in more detail, and
>> - skipping leading dot if one exists when creating/deleting events.
>
>  From the whole set I find that one hard to estimate without knowing more about
> general specs. Will the format on all arches require a ";" or ":" and none of
> "+@%" to differentiate a file from a function specification? If that is the case
> then the change looks ok.
>
> The remainder of patches always seem to insert new (weak) functions with the non
> ppc64el path being the same as before. So those seem ok.
>
> -Stefan
>

According to comments in the code, all arches have the same syntax with 
the exception of whether a function begins with a '.' (on ppc64el). As 
far as I can tell its doing the right thing. Also, this commit was 
merged as of 4.2-rc1 and I don't see any corrections to it up through 
4.3-rc1. I'm comfortable that if this had caused a regression then it 
would have been noticed by now.

rtg
-- 
Tim Gardner tim.gardner at canonical.com




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