From f6cd24777513fcc673d432cc29ef59881d3e4df1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 4 Nov 2010 11:13:48 +0100 Subject: [PATCH] irq: Better struct irqaction layout We currently use kmalloc-96 slab for struct irqaction allocations on 64bit arches. This is unfortunate because of possible false sharing and two cache lines accesses. Move 'name' and 'dir' fields at the end of the structure, and force a suitable alignement. Hot path fields now use one cache line on x86_64. Signed-off-by: Eric Dumazet Reviewed-by: Andi Kleen Cc: Peter Zijlstra LKML-Reference: <1288865628.2659.69.camel@edumazet-laptop> Signed-off-by: Thomas Gleixner --- include/linux/interrupt.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 79d0c4f6d071..55e0d4253e49 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -114,15 +114,15 @@ typedef irqreturn_t (*irq_handler_t)(int, void *); struct irqaction { irq_handler_t handler; unsigned long flags; - const char *name; void *dev_id; struct irqaction *next; int irq; - struct proc_dir_entry *dir; irq_handler_t thread_fn; struct task_struct *thread; unsigned long thread_flags; -}; + const char *name; + struct proc_dir_entry *dir; +} ____cacheline_internodealigned_in_smp; extern irqreturn_t no_action(int cpl, void *dev_id); -- 2.20.1