From d3dcb436f61593843af178d4a520c8c43c04d3fc Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Mon, 10 Jun 2013 12:19:17 +0100 Subject: irqdomain: make irq_linear_revmap() a fast path again Over the years, irq_linear_revmap() gained tests and checks to make sure callers were using it safely, which while important, also make it less of a fast path. After the irqdomain refactoring done recently, it is now possible to make irq_linear_revmap() a fast path again. This patch moves irq_linear_revmap() to the header file and makes it a static inline so that interrupt controller drivers using a linear mapping can decode the virq from a hwirq in just a couple of instructions. Signed-off-by: Grant Likely --- include/linux/irqdomain.h | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'include/linux/irqdomain.h') diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h index 6efbeccac56c..c983ed18c332 100644 --- a/include/linux/irqdomain.h +++ b/include/linux/irqdomain.h @@ -176,6 +176,22 @@ extern void irq_domain_associate_many(struct irq_domain *domain, extern unsigned int irq_create_mapping(struct irq_domain *host, irq_hw_number_t hwirq); extern void irq_dispose_mapping(unsigned int virq); + +/** + * irq_linear_revmap() - Find a linux irq from a hw irq number. + * @domain: domain owning this hardware interrupt + * @hwirq: hardware irq number in that domain space + * + * This is a fast path alternative to irq_find_mapping() that can be + * called directly by irq controller code to save a handful of + * instructions. It is always safe to call, but won't find irqs mapped + * using the radix tree. + */ +static inline unsigned int irq_linear_revmap(struct irq_domain *domain, + irq_hw_number_t hwirq) +{ + return hwirq < domain->revmap_size ? domain->linear_revmap[hwirq] : 0; +} extern unsigned int irq_find_mapping(struct irq_domain *host, irq_hw_number_t hwirq); extern unsigned int irq_create_direct_mapping(struct irq_domain *host); @@ -189,9 +205,6 @@ static inline int irq_create_identity_mapping(struct irq_domain *host, return irq_create_strict_mappings(host, hwirq, hwirq, 1); } -extern unsigned int irq_linear_revmap(struct irq_domain *host, - irq_hw_number_t hwirq); - extern const struct irq_domain_ops irq_domain_simple_ops; /* stock xlate functions */ -- cgit v1.2.3