Commit f2694ba5 authored by Michael Ellerman's avatar Michael Ellerman Committed by Benjamin Herrenschmidt
Browse files

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: default avatarMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent fb94fc2b

arch/powerpc/kernel/irq.c

+56 −40
Original line number Diff line number Diff line
@@ -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++;