Re: [PATCH V8 11/22] LoongArch: Add process management

[Huacai Chen]

Hi, Arnd,

On Mon, Mar 21, 2022 at 4:43 PM Arnd Bergmann <arnd@xxxxxxxx> wrote:
>
> On Sat, Mar 19, 2022 at 3:38 PM Huacai Chen <chenhuacai@xxxxxxxxxx> wrote:
>
> > +#ifdef CONFIG_PAGE_SIZE_64KB
> > +#define THREAD_SIZE_ORDER (0)
> > +#endif
> > +
> > +#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
> > +#define THREAD_MASK (THREAD_SIZE - 1UL)
> > +
>
> Having a 64KB stack area is rather wasteful. I think you should use a sub-page
> allocation in this configuration, or possibly disallow 64KB page configuration
> entirely.
>
> Note that you have to use full pages when using CONFIG_VMAP_STACK, but
> you don't seem to support that at the moment, so allocating only 16KB stacks
> on a 64KB page config should still work.
I think using a 16KB stack for all configurations (4KB/16KB/64KB) is
the simplest way. Right?

Huacai
>
>        Arnd