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From: Alexander Potapenko <glider@google.com>
Date: Tue, 2 Apr 2024 09:04:09 +0200
Message-ID: <CAG_fn=XL7tSuCuBXKf1YDiETkFMte7JyLrSE+saDthtJj==hUQ@mail.gmail.com>
Subject: Re: [PATCH] stackdepot: Rename pool_index to pool_index_plus_1
To: Vlastimil Babka <vbabka@suse.cz>
Cc: Peter Collingbourne <pcc@google.com>, Andrey Konovalov <andreyknvl@gmail.com>, 
	Oscar Salvador <osalvador@suse.de>, Andrew Morton <akpm@linux-foundation.org>, 
	linux-kernel@vger.kernel.org, linux-mm@kvack.org, 
	Michal Hocko <mhocko@suse.com>, Marco Elver <elver@google.com>, Omar Sandoval <osandov@fb.com>
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On Tue, Apr 2, 2024 at 8:54=E2=80=AFAM Vlastimil Babka <vbabka@suse.cz> wro=
te:
>
> On 4/2/24 2:14 AM, Peter Collingbourne wrote:
> > Commit 3ee34eabac2a ("lib/stackdepot: fix first entry having a
> > 0-handle") changed the meaning of the pool_index field to mean "the
> > pool index plus 1". This made the code accessing this field less
> > self-documenting, as well as causing debuggers such as drgn to not
> > be able to easily remain compatible with both old and new kernels,
> > because they typically do that by testing for presence of the new
> > field. Because stackdepot is a debugging tool, we should make sure
> > that it is debugger friendly. Therefore, give the field a different
> > name to improve readability as well as enabling debugger backwards
> > compatibility.
> >
> > Signed-off-by: Peter Collingbourne <pcc@google.com>
> > Link: https://linux-review.googlesource.com/id/Ib3e70c36c1d230dd0a118dc=
22649b33e768b9f88
>
> Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Alexander Potapenko <glider@google.com>