From 9c2555835bb3d34dfac52a0be943dcc4bedd650f Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 4 Jul 2016 17:39:23 +0900 Subject: [PATCH] genirq: Introduce IRQD_AFFINITY_MANAGED flag Interupts marked with this flag are excluded from user space interrupt affinity changes. Contrary to the IRQ_NO_BALANCING flag, the kernel internal affinity mechanism is not blocked. This flag will be used for multi-queue device interrupts. Signed-off-by: Thomas Gleixner Cc: Christoph Hellwig Cc: linux-block@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: linux-nvme@lists.infradead.org Cc: axboe@fb.com Cc: agordeev@redhat.com Link: http://lkml.kernel.org/r/1467621574-8277-3-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner --- include/linux/irq.h | 7 +++++++ kernel/irq/internals.h | 2 ++ kernel/irq/manage.c | 21 ++++++++++++++++++--- kernel/irq/proc.c | 2 +- 4 files changed, 28 insertions(+), 4 deletions(-) diff --git a/include/linux/irq.h b/include/linux/irq.h index 4d758a7c604a..f6074813688d 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -197,6 +197,7 @@ struct irq_data { * IRQD_IRQ_INPROGRESS - In progress state of the interrupt * IRQD_WAKEUP_ARMED - Wakeup mode armed * IRQD_FORWARDED_TO_VCPU - The interrupt is forwarded to a VCPU + * IRQD_AFFINITY_MANAGED - Affinity is auto-managed by the kernel */ enum { IRQD_TRIGGER_MASK = 0xf, @@ -212,6 +213,7 @@ enum { IRQD_IRQ_INPROGRESS = (1 << 18), IRQD_WAKEUP_ARMED = (1 << 19), IRQD_FORWARDED_TO_VCPU = (1 << 20), + IRQD_AFFINITY_MANAGED = (1 << 21), }; #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors) @@ -305,6 +307,11 @@ static inline void irqd_clr_forwarded_to_vcpu(struct irq_data *d) __irqd_to_state(d) &= ~IRQD_FORWARDED_TO_VCPU; } +static inline bool irqd_affinity_is_managed(struct irq_data *d) +{ + return __irqd_to_state(d) & IRQD_AFFINITY_MANAGED; +} + #undef __irqd_to_state static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 09be2c903c6d..b15aa3b617a2 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -105,6 +105,8 @@ static inline void unregister_handler_proc(unsigned int irq, struct irqaction *action) { } #endif +extern bool irq_can_set_affinity_usr(unsigned int irq); + extern int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask); extern void irq_set_thread_affinity(struct irq_desc *desc); diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index ef0bc02c3a70..30658e9827f0 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -115,12 +115,12 @@ EXPORT_SYMBOL(synchronize_irq); #ifdef CONFIG_SMP cpumask_var_t irq_default_affinity; -static int __irq_can_set_affinity(struct irq_desc *desc) +static bool __irq_can_set_affinity(struct irq_desc *desc) { if (!desc || !irqd_can_balance(&desc->irq_data) || !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity) - return 0; - return 1; + return false; + return true; } /** @@ -133,6 +133,21 @@ int irq_can_set_affinity(unsigned int irq) return __irq_can_set_affinity(irq_to_desc(irq)); } +/** + * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space + * @irq: Interrupt to check + * + * Like irq_can_set_affinity() above, but additionally checks for the + * AFFINITY_MANAGED flag. + */ +bool irq_can_set_affinity_usr(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + + return __irq_can_set_affinity(desc) && + !irqd_affinity_is_managed(&desc->irq_data); +} + /** * irq_set_thread_affinity - Notify irq threads to adjust affinity * @desc: irq descriptor which has affitnity changed diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 4e1b94726818..40bdcdc1f700 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -96,7 +96,7 @@ static ssize_t write_irq_affinity(int type, struct file *file, cpumask_var_t new_value; int err; - if (!irq_can_set_affinity(irq) || no_irq_affinity) + if (!irq_can_set_affinity_usr(irq) || no_irq_affinity) return -EIO; if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) -- 2.20.1