powerpc/irq: Move #ifdef'ed body of do_IRQ() into a separate function

Rather than a giant ifdef in the body of do_IRQ(), including a
dangling else, move the irq stack logic into a separate routine and
do the ifdef there.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 8c1a496..3d3658d 100644 (file)
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -248,13 +248,63 @@ void fixup_irqs(cpumask_t map)
 }
 #endif
 
+#ifdef CONFIG_IRQSTACKS
+static inline void handle_one_irq(unsigned int irq)
+{
+       struct thread_info *curtp, *irqtp;
+       unsigned long saved_sp_limit;
+       struct irq_desc *desc;
+       void *handler;
+
+       /* Switch to the irq stack to handle this */
+       curtp = current_thread_info();
+       irqtp = hardirq_ctx[smp_processor_id()];
+
+       if (curtp == irqtp) {
+               /* We're already on the irq stack, just handle it */
+               generic_handle_irq(irq);
+               return;
+       }
+
+       desc = irq_desc + irq;
+       saved_sp_limit = current->thread.ksp_limit;
+
+       handler = desc->handle_irq;
+       if (handler == NULL)
+               handler = &__do_IRQ;
+
+       irqtp->task = curtp->task;
+       irqtp->flags = 0;
+
+       /* Copy the softirq bits in preempt_count so that the
+        * softirq checks work in the hardirq context. */
+       irqtp->preempt_count = (irqtp->preempt_count & ~SOFTIRQ_MASK) |
+                              (curtp->preempt_count & SOFTIRQ_MASK);
+
+       current->thread.ksp_limit = (unsigned long)irqtp +
+               _ALIGN_UP(sizeof(struct thread_info), 16);
+
+       call_handle_irq(irq, desc, irqtp, handler);
+       current->thread.ksp_limit = saved_sp_limit;
+       irqtp->task = NULL;
+
+       /* Set any flag that may have been set on the
+        * alternate stack
+        */
+       if (irqtp->flags)
+               set_bits(irqtp->flags, &curtp->flags);
+}
+#else
+static inline void handle_one_irq(unsigned int irq)
+{
+       generic_handle_irq(irq);
+}
+#endif
+
 void do_IRQ(struct pt_regs *regs)
 {
        struct pt_regs *old_regs = set_irq_regs(regs);
        unsigned int irq;
-#ifdef CONFIG_IRQSTACKS
-       struct thread_info *curtp, *irqtp;
-#endif
 
        irq_enter();
 
@@ -282,43 +332,9 @@ void do_IRQ(struct pt_regs *regs)
         */
        irq = ppc_md.get_irq();
 
-       if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
-#ifdef CONFIG_IRQSTACKS
-               /* Switch to the irq stack to handle this */
-               curtp = current_thread_info();
-               irqtp = hardirq_ctx[smp_processor_id()];
-               if (curtp != irqtp) {
-                       struct irq_desc *desc = irq_desc + irq;
-                       void *handler = desc->handle_irq;
-                       unsigned long saved_sp_limit = current->thread.ksp_limit;
-                       if (handler == NULL)
-                               handler = &__do_IRQ;
-                       irqtp->task = curtp->task;
-                       irqtp->flags = 0;
-
-                       /* Copy the softirq bits in preempt_count so that the
-                        * softirq checks work in the hardirq context.
-                        */
-                       irqtp->preempt_count =
-                               (irqtp->preempt_count & ~SOFTIRQ_MASK) |
-                               (curtp->preempt_count & SOFTIRQ_MASK);
-
-                       current->thread.ksp_limit = (unsigned long)irqtp +
-                               _ALIGN_UP(sizeof(struct thread_info), 16);
-                       call_handle_irq(irq, desc, irqtp, handler);
-                       current->thread.ksp_limit = saved_sp_limit;
-                       irqtp->task = NULL;
-
-
-                       /* Set any flag that may have been set on the
-                        * alternate stack
-                        */
-                       if (irqtp->flags)
-                               set_bits(irqtp->flags, &curtp->flags);
-               } else
-#endif
-                       generic_handle_irq(irq);
-       } else if (irq != NO_IRQ_IGNORE)
+       if (irq != NO_IRQ && irq != NO_IRQ_IGNORE)
+               handle_one_irq(irq);
+       else if (irq != NO_IRQ_IGNORE)
                /* That's not SMP safe ... but who cares ? */
                ppc_spurious_interrupts++;