From f31078b5825f71499fa95b85babf6ac8c776c37d 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 Change-Id: Ibeec0031edb532d52cb411286f785aec160d6139 --- include/linux/irq.h | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'include/linux/irq.h') diff --git a/include/linux/irq.h b/include/linux/irq.h index 8da001eb82aa..0e57f41bde84 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -136,6 +136,9 @@ struct irq_domain; * @node: node index useful for balancing * @handler_data: per-IRQ data for the irq_chip methods * @affinity: IRQ affinity on SMP + * @effective_affinity: The effective IRQ affinity on SMP as some irq + * chips do not allow multi CPU destinations. + * A subset of @affinity. * @msi_desc: MSI descriptor */ struct irq_common_data { @@ -146,6 +149,9 @@ struct irq_common_data { void *handler_data; struct msi_desc *msi_desc; cpumask_var_t affinity; +#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK + cpumask_var_t effective_affinity; +#endif }; /** @@ -690,6 +696,29 @@ static inline struct cpumask *irq_data_get_affinity_mask(struct irq_data *d) return d->common->affinity; } +#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK +static inline +struct cpumask *irq_data_get_effective_affinity_mask(struct irq_data *d) +{ + return d->common->effective_affinity; +} +static inline void irq_data_update_effective_affinity(struct irq_data *d, + const struct cpumask *m) +{ + cpumask_copy(d->common->effective_affinity, m); +} +#else +static inline void irq_data_update_effective_affinity(struct irq_data *d, + const struct cpumask *m) +{ +} +static inline +struct cpumask *irq_data_get_effective_affinity_mask(struct irq_data *d) +{ + return d->common->affinity; +} +#endif + unsigned int arch_dynirq_lower_bound(unsigned int from); int __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node, -- cgit v1.2.3