[PATCH v10 13/17] powerpc/64s: Add support to mask perf interrupts and replay them

[Nicholas Piggin]

On Wed, 20 Dec 2017 09:25:53 +0530
Madhavan Srinivasan <maddy at linux.vnet.ibm.com> wrote:

> Two new bit mask field "IRQ_DISABLE_MASK_PMU" is introduced to support
> the masking of PMI and "IRQ_DISABLE_MASK_ALL" to aid interrupt masking
> checking.
> 
> Couple of new irq #defs "PACA_IRQ_PMI" and "SOFTEN_VALUE_0xf0*" added
> to use in the exception code to check for PMI interrupts.
> 
> In the masked_interrupt handler, for PMIs we reset the MSR[EE] and
> return. In the __check_irq_replay(), replay the PMI interrupt by
> calling performance_monitor_common handler.

I think we need to add all interrupt types which clear MSR[EE] in their
masked handler to the test in may_hard_irq_disable(), otherwise EE can
be enabled before all such pending interrupts are replayed.

We should define all such interrupts in a mask and use that in
may_hard_irq_disable() and corresponding place in masked_##_H##interrupt:

Thanks,
Nick