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Subject: Re: [PATCH 1/2] futex: mark futex_detect_cmpxchg() as 'noinline'
To:     Arnd Bergmann <arnd@kernel.org>
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From:   Andreas Larsson <andreas@gaisler.com>
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Date:   Fri, 18 Dec 2020 12:08:23 +0100
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On 2020-12-17 17:43, Arnd Bergmann wrote:
> It does make sense to require that a single kernel can work on all
> possible hardware. So if we remove sun4m/sun4d support, all that
> is left is LEON, and you likely wouldn't need to worry about other
> CPUs any more.
> 
> However, there is still the question whether a single kernel needs
> to work on LEON both with and without CASA. Do you still care
> about Linux users on LEON cores that do not support CASA, or is
> widespread enough that you just make it unconditional for both
> SMP and non-SMP?

We are fine with unconditional CASA for both SMP and non-SMP for LEON.


> I hope that you can make it to 5.10 then, as this contains the work
> I did for 64-bit time_t, which is required if you have users that want to
> run systems after 2038.

That is a good point! Thank you!


> FWIW, glibc-2.31 does not have support for 64-bit time_t yet, but I
> know there was interest in adding sparc support to the musl libc, which
> does support 64-bit time_t.

Yes, we will have to follow the developments regarding 64-bit time_t
in GLIBC as well.

-- 
Andreas