From 0d3f54257dc300f2db480d6a46b34bdb87f18c1b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 20 Jun 2017 01:37:38 +0200 Subject: genirq: Introduce effective affinity mask There is currently no way to evaluate the effective affinity mask of a given interrupt. Many irq chips allow only a single target CPU or a subset of CPUs in the affinity mask. Updating the mask at the time of setting the affinity to the subset would be counterproductive because information for cpu hotplug about assigned interrupt affinities gets lost. On CPU hotplug it's also pointless to force migrate an interrupt, which is not targeted at the CPU effectively. But currently the information is not available. Provide a seperate mask to be updated by the irq_chip->irq_set_affinity() implementations. Implement the read only proc files so the user can see the effective mask as well w/o trying to deduce it from /proc/interrupts. Signed-off-by: Thomas Gleixner Cc: Jens Axboe Cc: Marc Zyngier Cc: Michael Ellerman Cc: Keith Busch Cc: Peter Zijlstra Cc: Christoph Hellwig Link: http://lkml.kernel.org/r/20170619235446.247834245@linutronix.de --- kernel/irq/Kconfig | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'kernel/irq/Kconfig') diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 8d9498e51585..fcbb1d6d51cb 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -21,6 +21,10 @@ config GENERIC_IRQ_SHOW config GENERIC_IRQ_SHOW_LEVEL bool +# Supports effective affinity mask +config GENERIC_IRQ_EFFECTIVE_AFF_MASK + bool + # Facility to allocate a hardware interrupt. This is legacy support # and should not be used in new code. Use irq domains instead. config GENERIC_IRQ_LEGACY_ALLOC_HWIRQ -- cgit v1.2.3