Re: [PATCH V6 0/3] Integration of function trace with System Trace IP blocks

[Chunyan Zhang]

Hi Balbi,

On 8 September 2016 at 20:07, Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> wrote:
>
> Hi,
>
> Chunyan Zhang <zhang.chunyan@xxxxxxxxxx> writes:
>> IP blocks allowing a variety of trace sources to log debugging
>> information to a pre-defined area have been introduced on a couple of
>> architecture [1][2]. These system trace blocks (also known as STM)
>> typically follow the MIPI STPv2 protocol [3] and provide a system wide
>> logging facility to any device, running a kernel or not, with access
>> to the block's log entry port(s).  Since each trace message has a
>> timestamp, it is possible to correlate events happening in the entire
>> system rather than being confined to the logging facility of a single
>> entity.
>>
>> This patchset is trying to use STM IP blocks to store function tracing
>> information produced by Ftrace and I'm taking the Function trace
>> (trace type is TRACE_FN) as the example in this patchset, but other
>> types of traces also can be supported.
>>
>> Logging information generated by the Ftrace subsystem to STM and gathered
>> in the sink device can be used in conjunction with trace data from other
>> board components, also collected in the same trace sink.
>>
>> This example is using ARM coresight STM but the same would apply to any
>> other architecture wishing to do the same.
>>
>> Comments would be greatly appreciated.
>
> showing up late to the bandwagon, but this is very good. I've been
> toying with the idea of exporting ftrace via USB and this will help
> quite a bit. Thanks :-)

Very happy this work may be helpful for you.

>
> I'll add to my TODO a look at this series. Great work.

Yes, please help review, comments are very welcome.

There's still some other work related this need to be done, this
patch-set is the first step.  I will keep you posted with any update.


Thanks,
Chunyan

>
> --
> balbi