Commit-ID: 6ed3464897cc825a75218653c710d673282dfcf8 Gitweb: http://git.kernel.org/tip/6ed3464897cc825a75218653c710d673282dfcf8 Author: Felipe Balbi <[email protected]> AuthorDate: Fri, 2 Jan 2015 16:18:54 -0600 Committer: Thomas Gleixner <[email protected]> CommitDate: Wed, 22 Jul 2015 18:37:42 +0200
irqchip: omap-intc: Improve IRQ handler As it turns out the current IRQ number will *always* be available from SIR register which renders the reads of PENDING registers as plain unnecessary overhead. In order to catch any situation where SIR reads as zero, we're adding a WARN() to turn it into a very verbose error and users actually report it. With this patch average running time of omap_intc_handle_irq() reduced from about 28.5us to 19.8us as measured by the kernel function profiler. Tested with BeagleBoneBlack Rev A5C. Tested-by: Tony Lindgren <[email protected]> Signed-off-by: Felipe Balbi <[email protected]> Cc: Linux ARM Kernel Mailing List <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]> --- drivers/irqchip/irq-omap-intc.c | 35 +++++------------------------------ 1 file changed, 5 insertions(+), 30 deletions(-) diff --git a/drivers/irqchip/irq-omap-intc.c b/drivers/irqchip/irq-omap-intc.c index 6cc0ad5..8587d0f 100644 --- a/drivers/irqchip/irq-omap-intc.c +++ b/drivers/irqchip/irq-omap-intc.c @@ -330,37 +330,12 @@ static int __init omap_init_irq(u32 base, struct device_node *node) static asmlinkage void __exception_irq_entry omap_intc_handle_irq(struct pt_regs *regs) { - u32 irqnr = 0; - int handled_irq = 0; - int i; - - do { - for (i = 0; i < omap_nr_pending; i++) { - irqnr = intc_readl(INTC_PENDING_IRQ0 + (0x20 * i)); - if (irqnr) - goto out; - } - -out: - if (!irqnr) - break; - - irqnr = intc_readl(INTC_SIR); - irqnr &= ACTIVEIRQ_MASK; + u32 irqnr; - if (irqnr) { - handle_domain_irq(domain, irqnr, regs); - handled_irq = 1; - } - } while (irqnr); - - /* - * If an irq is masked or deasserted while active, we will - * keep ending up here with no irq handled. So remove it from - * the INTC with an ack. - */ - if (!handled_irq) - omap_ack_irq(NULL); + irqnr = intc_readl(INTC_SIR); + irqnr &= ACTIVEIRQ_MASK; + WARN_ONCE(!irqnr, "Spurious IRQ ?\n"); + handle_domain_irq(domain, irqnr, regs); } void __init omap3_init_irq(void) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
