Re: CONFIG_PREEMPT_DYNAMIC=y?

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From	Diederik de Haas <didi.debian@cknow.org>
Newsgroups	linux.debian.kernel
Subject	Re: CONFIG_PREEMPT_DYNAMIC=y?
Date	Tue, 10 Oct 2023 15:20:01 +0200
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On Tuesday, 10 October 2023 14:17:50 CEST Vincent Blut wrote:
> > Neither does amd64. So it appears something else is causing
> > CONFIG_PREEMPT_DYNAMIC to be enabled on amd64.
> 
> From the commit message introducing PREEMPT_DYNAMIC:¹
> 
>     CONFIG_PREEMPT_DYNAMIC is automatically selected by CONFIG_PREEMPT if
>     the architecture provides the necessary support
> (CONFIG_STATIC_CALL_INLINE, CONFIG_GENERIC_ENTRY, and provide with
> __preempt_schedule_function() / __preempt_schedule_notrace_function()).

And CONFIG_PREEMPT was explicitly disabled on 2007-05-21 in 
8ec9ee1435ba3ac97f9f0e7c5b879aac8d636f4a (I couldn't find an older commit).
So I guess the heuristic isn't applied as the precondition already fails.

Thanks for finding that part :-)

Thread

CONFIG_PREEMPT_DYNAMIC=y? Johannes Schauer Marin Rodrigues <josch@debian.org> - 2023-10-08 18:30 +0200
  Re: CONFIG_PREEMPT_DYNAMIC=y? Diederik de Haas <didi.debian@cknow.org> - 2023-10-08 19:30 +0200
    Re: CONFIG_PREEMPT_DYNAMIC=y? Emanuele Rocca <ema@debian.org> - 2023-10-10 12:10 +0200
      Re: CONFIG_PREEMPT_DYNAMIC=y? Johannes Schauer Marin Rodrigues <josch@debian.org> - 2023-10-10 12:20 +0200
        Re: CONFIG_PREEMPT_DYNAMIC=y? Emanuele Rocca <ema@debian.org> - 2023-10-10 12:40 +0200
          Re: CONFIG_PREEMPT_DYNAMIC=y? Marc Haber <mh+debian-kernel@zugschlus.de> - 2023-10-10 15:50 +0200
      Re: CONFIG_PREEMPT_DYNAMIC=y? Diederik de Haas <didi.debian@cknow.org> - 2023-10-10 14:00 +0200
        Re: CONFIG_PREEMPT_DYNAMIC=y? Vincent Blut <vincent.debian@free.fr> - 2023-10-10 14:20 +0200
          Re: CONFIG_PREEMPT_DYNAMIC=y? Diederik de Haas <didi.debian@cknow.org> - 2023-10-10 15:20 +0200
        Re: CONFIG_PREEMPT_DYNAMIC=y? Emanuele Rocca <ema@debian.org> - 2023-10-10 15:00 +0200
          Re: CONFIG_PREEMPT_DYNAMIC=y? Diederik de Haas <didi.debian@cknow.org> - 2023-10-10 23:30 +0200
            Re: CONFIG_PREEMPT_DYNAMIC=y? Diederik de Haas <didi.debian@cknow.org> - 2023-10-17 20:00 +0200
  Re: CONFIG_PREEMPT_DYNAMIC=y? Emanuele Rocca <ema@debian.org> - 2023-10-20 20:40 +0200

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