From 9b2b76a3344146c4d8d300874e73af8161204f87 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 6 Feb 2009 14:09:40 -0800 Subject: [PATCH] x86: add handle_irq() to allow interrupt injection Xen uses a different interrupt path, so introduce handle_irq() to allow interrupts to be inserted into the normal interrupt path. This is handled slightly differently on 32 and 64-bit. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Ingo Molnar --- arch/x86/include/asm/irq.h | 1 + arch/x86/kernel/irq_32.c | 34 +++++++++++++++++++++------------- arch/x86/kernel/irq_64.c | 23 ++++++++++++++++------- 3 files changed, 38 insertions(+), 20 deletions(-) diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h index 592688ed04d..d0f6f7d1771 100644 --- a/arch/x86/include/asm/irq.h +++ b/arch/x86/include/asm/irq.h @@ -39,6 +39,7 @@ extern void fixup_irqs(void); extern unsigned int do_IRQ(struct pt_regs *regs); extern void init_IRQ(void); extern void native_init_IRQ(void); +extern bool handle_irq(unsigned irq, struct pt_regs *regs); /* Interrupt vector management */ extern DECLARE_BITMAP(used_vectors, NR_VECTORS); diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c index d802c844991..61f09fb969e 100644 --- a/arch/x86/kernel/irq_32.c +++ b/arch/x86/kernel/irq_32.c @@ -191,6 +191,26 @@ static inline int execute_on_irq_stack(int overflow, struct irq_desc *desc, int irq) { return 0; } #endif +bool handle_irq(unsigned irq, struct pt_regs *regs) +{ + struct irq_desc *desc; + int overflow; + + overflow = check_stack_overflow(); + + desc = irq_to_desc(irq); + if (unlikely(!desc)) + return false; + + if (!execute_on_irq_stack(overflow, desc, irq)) { + if (unlikely(overflow)) + print_stack_overflow(); + desc->handle_irq(irq, desc); + } + + return true; +} + /* * do_IRQ handles all normal device IRQ's (the special * SMP cross-CPU interrupts have their own specific @@ -200,31 +220,19 @@ unsigned int do_IRQ(struct pt_regs *regs) { struct pt_regs *old_regs; /* high bit used in ret_from_ code */ - int overflow; unsigned vector = ~regs->orig_ax; - struct irq_desc *desc; unsigned irq; - old_regs = set_irq_regs(regs); irq_enter(); irq = __get_cpu_var(vector_irq)[vector]; - overflow = check_stack_overflow(); - - desc = irq_to_desc(irq); - if (unlikely(!desc)) { + if (!handle_irq(irq, regs)) { printk(KERN_EMERG "%s: cannot handle IRQ %d vector %#x cpu %d\n", __func__, irq, vector, smp_processor_id()); BUG(); } - if (!execute_on_irq_stack(overflow, desc, irq)) { - if (unlikely(overflow)) - print_stack_overflow(); - desc->handle_irq(irq, desc); - } - irq_exit(); set_irq_regs(old_regs); return 1; diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index 018963aa6ee..a93f3b0dc7f 100644 --- a/arch/x86/kernel/irq_64.c +++ b/arch/x86/kernel/irq_64.c @@ -48,6 +48,20 @@ static inline void stack_overflow_check(struct pt_regs *regs) #endif } +bool handle_irq(unsigned irq, struct pt_regs *regs) +{ + struct irq_desc *desc; + + stack_overflow_check(regs); + + desc = irq_to_desc(irq); + if (unlikely(!desc)) + return false; + + generic_handle_irq_desc(irq, desc); + return true; +} + /* * do_IRQ handles all normal device IRQ's (the special * SMP cross-CPU interrupts have their own specific @@ -56,7 +70,6 @@ static inline void stack_overflow_check(struct pt_regs *regs) asmlinkage unsigned int __irq_entry do_IRQ(struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs); - struct irq_desc *desc; /* high bit used in ret_from_ code */ unsigned vector = ~regs->orig_ax; @@ -64,14 +77,10 @@ asmlinkage unsigned int __irq_entry do_IRQ(struct pt_regs *regs) exit_idle(); irq_enter(); - irq = __get_cpu_var(vector_irq)[vector]; - stack_overflow_check(regs); + irq = __get_cpu_var(vector_irq)[vector]; - desc = irq_to_desc(irq); - if (likely(desc)) - generic_handle_irq_desc(irq, desc); - else { + if (!handle_irq(irq, regs)) { if (!disable_apic) ack_APIC_irq(); -- 2.20.1