RFC: Standalone AutoFDO Profile Tool for GCC

[Kugan Vivekanandarajah]

> On 6 May 2026, at 8:16 am, Andi Kleen <andi@firstfloor.org> wrote:
> 
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> 
>>> I also wonder if there is a chance for collaboration/integration with perf
>>> tools itself.
>>> In particular, the current tool is picky about perf.data file format that
>>> is not completely
>>> stable.
> 
> That perf.data format is stable, but it supports extensions,
> and the perf library that autofdo uses didn't use to ignore
> unknown ones. I thought that had been fixed however.
> I don't think the format is a problem for a well written reader.
> 
>> So perhaps the perf.data loading can be sharing a library with
>>> perftools.
> 
> There is libperf, but I wouldn't use it. The interface to it
> definitely isn't stable, as well as being convoluted.
> 
> There are lots of third party libraries that can read perf.data however,
> or you can use a perf script extension like the one below.

We limited the perf parsing to only what we wanted. If there is an easier way to seperate this out and use an exiting library, that would be great.
I am open for suggestions.

Thanks,
Kugan