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Subject: Re: [Proposal] Adding callback support for custom statistics kinds
From: Chao Li <li.evan.chao@gmail.com>
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Date: Wed, 10 Dec 2025 07:05:42 +0800
Cc: Michael Paquier <michael@paquier.xyz>,
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To: Sami Imseih <samimseih@gmail.com>
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> On Dec 10, 2025, at 05:54, Sami Imseih <samimseih@gmail.com> wrote:
>=20
> IIUC, if *any* error occurs outside of a deserialize callback, first =
the "error"
> code will be called, followed by "done" which will then trigger the
> end_extra_stats
> callback that will perform the cleanup.

That is true. But problem is, without an error indication, =
end_extra_stats(STATS_READ) can only blindly perform cleanup works. As =
you are providing general purposed callbacks, who knows what scenarios =
extensions would do, so it=E2=80=99s better to provide more information =
to callbacks. IMO, letting end_extra_stats() know current situation =
(normal or failure, even error code) is very meaningful. For example, my =
extension may want to log =E2=80=9CI am forced to quite due to outside =
error=E2=80=9D or =E2=80=9CI am done successfully=E2=80=9D in =
end_extra_stats(). Anyway, that=E2=80=99s my own opinion. If you and =
Michael still consider that=E2=80=99s not a problem, I won=E2=80=99t =
argue more.

Best reagards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/