ARM: implement IRQ stacks

[linux-2.6-microblaze.git] / arch / arm / kernel / irq.c

diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c
index b79975b..abb0aa6 100644 (file)
--- a/arch/arm/kernel/irq.c
+++ b/arch/arm/kernel/irq.c
@@ -43,6 +43,25 @@
 
 unsigned long irq_err_count;
 
+#ifdef CONFIG_IRQSTACKS
+
+asmlinkage DEFINE_PER_CPU_READ_MOSTLY(u8 *, irq_stack_ptr);
+
+static void __init init_irq_stacks(void)
+{
+       u8 *stack;
+       int cpu;
+
+       for_each_possible_cpu(cpu) {
+               stack = (u8 *)__get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
+               if (WARN_ON(!stack))
+                       break;
+               per_cpu(irq_stack_ptr, cpu) = &stack[THREAD_SIZE];
+       }
+}
+
+#endif
+
 int arch_show_interrupts(struct seq_file *p, int prec)
 {
 #ifdef CONFIG_FIQ
@@ -101,6 +120,10 @@ void __init init_IRQ(void)
 {
        int ret;
 
+#ifdef CONFIG_IRQSTACKS
+       init_irq_stacks();
+#endif
+
        if (IS_ENABLED(CONFIG_OF) && !machine_desc->init_irq)
                irqchip_init();
        else