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Date: Fri, 31 May 2024 17:38:23 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>, jpoimboe@kernel.org,
 kent.overstreet@linux.dev, peterz@infradead.org, nphamcs@gmail.com,
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 willy@infradead.org, vbabka@suse.cz, ziy@nvidia.com,
 linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH v3] vmstat: Kernel stack usage histogram
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On Thu, 30 May 2024 20:14:17 -0400 Pasha Tatashin <pasha.tatashin@soleen.com> wrote:

> > Couple of questions:
> >
> > 1. In future with your on-demand kstack allocation feature, will these
> > metrics still be useful? (I think so but I want to know your take)

I do think the changelog for this patch should reference the dynamic
stack feature.  It strengthens the justification for adding this patch.

> It depends on how on-demand allocation is implemented. On hardware
> that supports faults on kernel stacks, we will have other metrics that
> show the total number of pages allocated for stacks. On hardware where
> faults are not supported, we will most likely have some optimization
> where only some threads are extended, and for those, these metrics
> will still be very useful.

Also useful changelog info for this patch.

Pasha, could you please prepare some additional text which I can paste
in?  Thanks.