Re: [PATCH RFC 11/14] arm64: Move the ASID allocator code in a separate file

[Guo Ren]

On Wed, Jun 19, 2019 at 4:54 PM Julien Grall <julien.grall@xxxxxxx> 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@xxxxxxxxxx/
> >
> > 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