This is enough to get the NMIs working, more work is needed
for perf events.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We assumed PCR_PIC_PRIV can always be used to disable it, but that
won't be true for SPARC-T4.

This allows us also to get rid of some messy defines used in only
one location.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

And, like for the PCR, allow indexing of different PIC register
numbers.

This also removes all of the non-__KERNEL__ bits from asm/perfctr.h,
nothing kernel side should include it any more.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SPARC-T4 and later have multiple PCR registers, one for each
PIC counter.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Doing NMI startup as an early initcall doesn't work because we need
to have SMP started up by then.

So we'd only NMI startup one cpu, which causes perf PMU grab to
BUG because the nmi_active count isn't what it's supposed to be.

This also points out that we don't have proper CPU up/down notifiers
for the NMI code which will need to be fixed at some point.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It all lives in the oprofile support code currently and we will need
to share this stuff with NMI watchdog and perf_counter support.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>