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From:   Guo Ren <guoren@kernel.org>
Date:   Wed, 19 Jun 2019 19:51:03 +0800
Message-ID: <CAJF2gTStSR7Jmu7=HaO5Wxz=Zn8A5-RD8ktori3oKEhM9vozAA@mail.gmail.com>
Subject: Re: [PATCH RFC 11/14] arm64: Move the ASID allocator code in a
 separate file
To:     Julien Grall <julien.grall@arm.com>
Cc:     linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        kvmarm@lists.cs.columbia.edu, aou@eecs.berkeley.edu,
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        Marc Zyngier <marc.zyngier@arm.com>, catalin.marinas@arm.com,
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On Wed, Jun 19, 2019 at 4:54 PM Julien Grall <julien.grall@arm.com> wrote:
>
>
>
> On 6/19/19 9:07 AM, Guo Ren wrote:
> > Hi Julien,
>
> Hi,
>
> >
> > You forgot CCing C-SKY folks :P
>
> I wasn't aware you could be interested :).
>
> >
> > Move arm asid allocator code in a generic one is a agood idea, I've
> > made a patchset for C-SKY and test is on processing, See:
> > https://lore.kernel.org/linux-csky/1560930553-26502-1-git-send-email-guoren@kernel.org/
> >
> > If you plan to seperate it into generic one, I could co-work with you.
>
> Was the ASID allocator work out of box on C-Sky?
Almost done, but one question:
arm64 remove the code in switch_mm:
  cpumask_clear_cpu(cpu, mm_cpumask(prev));
  cpumask_set_cpu(cpu, mm_cpumask(next));

Why? Although arm64 cache operations could affect all harts with CTC
method of interconnect, I think we should
keep these code for primitive integrity in linux. Because cpu_bitmap
is in mm_struct instead of mm->context.

In current csky's patches I've also removed the codes the same as
arm64, but I'll add it back at next version.

> If so, I can easily move the code in a generic place (maybe lib/asid.c).
I think it's OK.

Best Regards
 Guo Ren