Re: [RFC PATCH 1/6] perf: Move mlock accounting to ring buffer allocation

From: Peter Zijlstra
Date: Fri Sep 23 2016 - 11:27:44 EST


On Fri, Sep 23, 2016 at 05:27:22PM +0300, Alexander Shishkin wrote:
> > Afaict there's no actual need to hide the AUX buffer for this sampling
> > stuff; the user knows about all this and can simply mmap() the AUX part.
>
> Yes, you're right here. We could also re-use the AUX record, adding a
> new flag for this. It may be even better if I can work out the
> inheritance (the current code doesn't handle inheritance at the moment
> in case we decide to scrap it).

What is the exact problem with inheritance? You can inherit PT (and
other) events just fine, and their output redirects to the original
(AUX) buffer too.

Is the problem untangling which part of the AUX buffer belongs to which
task upon sample?