sched_pin() versus PCPU_GET

[mdf at FreeBSD.org]

On Wed, Aug 4, 2010 at 9:20 AM,  <mdf at freebsd.org> wrote:
> On Wed, Aug 4, 2010 at 2:26 PM, John Baldwin <jhb at freebsd.org> wrote:
>> Actually, I would beg to differ in that case.  If PCPU_GET(spinlocks)
>> returns non-NULL, then it means that you hold a spin lock,
>
> ll_count is 0 for the "correct" pc_spinlocks and non-zero for the
> "wrong" one, though.  So I think it can be non-NULL but the current
> thread/CPU doesn't hold a spinlock.
>
> I don't believe we have any code in the NMI handler.  I'm on vacation
> today so I'll check tomorrow.

I checked and ipi_nmi_handler() doesn't appear to have any local
changes.  I assume that's where I should look?

Thanks,
matthew