powerpc/powernv: process all OPAL event interrupts with kopald

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Using irq_work for processing OPAL event interrupts is not necessary.
irq_work is typically used to schedule work from NMI context, a
softirq may be more appropriate. However OPAL events are not
particularly performance or latency critical, so they can all be
invoked by kopald.

This patch removes the irq_work queueing, and instead wakes up
kopald when there is an event to be processed. kopald processes
interrupts individually, enabling irqs and calling cond_resched
between each one to minimise latencies.

Event handlers themselves should still use threaded handlers,
workqueues, etc. as necessary to avoid high interrupts-off latencies
within any single interrupt.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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Nicholas Piggin 2018-05-11 03:20:05 +10:00 • committed by Michael Ellerman

parent ee03b9b447

commit 56c0b48b1e

3 changed files with 52 additions and 61 deletions

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85

arch/powerpc/platforms/powernv/opal-irqchip.c

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23

arch/powerpc/platforms/powernv/opal.c

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3

arch/powerpc/platforms/powernv/powernv.h

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