Re: [PATCH] of: introduce event tracepoints for dynamic device_node lifecyle

From: Frank Rowand
Date: Thu Apr 20 2017 - 06:45:08 EST


On 04/19/17 19:37, Frank Rowand wrote:
> On 04/19/17 11:45, Tyrel Datwyler wrote:
>> On 04/18/2017 07:49 PM, Steven Rostedt wrote:
>>> On Tue, 18 Apr 2017 18:42:32 -0700
>>> Frank Rowand <frowand.list@xxxxxxxxx> wrote:
>>>
>>>> And of course the other issue with using tracepoints is the extra space
>>>> required to hold the tracepoint info. With the pr_debug() approach, the
>>>> space usage can be easily removed for a production kernel via a config
>>>> option.
>>>
>>> Now if you are saying you want to be able to enable debugging without
>>> the tracing infrastructure I would agree. As the tracing infrastructure
>>> is large. But I'm working on shrinking it more.
>>
>> The primary consumers of OF_DYNAMIC seem to be pseries and powernv where
>> we are generally going to see the trace infrastructure enabled by
>> default in production.
>
> Another primary consumer will be overlays for ARM expansion boards. Still
> a work in progress.

And dynamic configuration for the FPGA folks.


> -Frank
>
>>
>> -Tyrel
>>
>>>
>>>>
>>>> Tracepoints are wonderful technology, but not always the proper tool to
>>>> use for debug info.
>>>
>>> But if you are going to have tracing enabled regardless, adding a few
>>> more tracepoints isn't going to make the difference.
>>>
>>> -- Steve
>>>
>>>>
>>>>> If Rob wants to convert printk() style data to trace data (and I can't
>>>>> convince him otherwise) then I will have further comments on this specific
>>>>> patch.
>>>>>
>>
>> .
>>
>
> .
>