Patch: SMP support for MIPS

[Neel Natu]

Hi Warner,

Thanks for looking at this.

On Fri, Feb 5, 2010 at 7:01 PM, M. Warner Losh <imp at bsdimp.com> wrote:
> In message: <dffe84831002051827r430c7fb6le3c3506bd6d38a03 at mail.gmail.com>
>            Neel Natu <neelnatu at gmail.com> writes:
> : I have put the diff here for review:
> : http://people.freebsd.org/~neel/mips_smp_patch/diff.txt
>
> + /*
> +  * XXX
> +   * SMP kernels must delay pcpu initialization until after
> +    * TLB has been flushed and initialized (see mips_cpu_init())
> +     */
> +     if (pcpu_find(0) == NULL)
> +        mips_pcpu0_init();
> +
>
> The practical upshot of this change is that panic() prior to this
> point will fault.  Is there some way to avoid this?
>

That's right. I have this fixed in the updated patch. Please review
the changes to pmap.c and machdep.c.
http://people.freebsd.org/~neel/mips_smp_patch/diff.txt

Briefly, we use an address in KSEG0 for the 'pcpup' until we are ready
to transition to a TLB-based pcpu pointer.

> The rest of these changes look fairly good.  I'll likely comment on a
> few nits later that I saw once I have the time to devote to it.
>

Ok.

best
Neel

> Warner
>