- Provide lapic_disable_pmc(), lapic_enable_pmc(), and lapic_reenable_pmc()
routines in the local APIC code that the hwpmc(4) driver can use to
manage the local APIC PMC interrupt vector.
- Do not enable the local APIC PMC interrupt vector by default when
HWPMC_HOOKS is enabled. Instead, the hwpmc(4) driver explicitly
enables the interrupt when it is succesfully initialized and disables
the interrupt when it is unloaded. This avoids enabling the interrupt
on unsupported CPUs which may result in spurious NMIs.
Reported by: rnoland
Reviewed by: jkoshy
Approved by: re (kib)
MFC after: 2 weeks
d51166f15e