genirq: Remove CONFIG_IRQ_PER_CPU

The saving of this switch is minimal versus the ifdef mess it
creates. Simple enable PER_CPU unconditionally and remove the config
switch.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

include/linux/irq.h

@@ -78,13 +78,8 @@ typedef	void (*irq_flow_handler_t)(unsigned int irq,
 	 IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \
 	 IRQ_PER_CPU | IRQ_NESTED_THREAD)
 
-#ifdef CONFIG_IRQ_PER_CPU
 # define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)
 # define IRQ_NO_BALANCING_MASK	(IRQ_PER_CPU | IRQ_NO_BALANCING)
-#else
-# define CHECK_IRQ_PER_CPU(var) 0
-# define IRQ_NO_BALANCING_MASK	IRQ_NO_BALANCING
-#endif
 
 /*
  * Return value for chip->irq_set_affinity()

kernel/irq/Kconfig

@@ -32,9 +32,6 @@ config GENERIC_PENDING_IRQ
 config AUTO_IRQ_AFFINITY
        def_bool n
 
-config IRQ_PER_CPU
-       def_bool n
-
 config HARDIRQS_SW_RESEND
        def_bool n
 

kernel/irq/internals.h

@@ -163,9 +163,7 @@ static inline void print_irq_desc(unsigned int irq, struct irq_desc *desc)
 	}
 
 	P(IRQ_LEVEL);
-#ifdef CONFIG_IRQ_PER_CPU
 	P(IRQ_PER_CPU);
-#endif
 	P(IRQ_NOPROBE);
 	P(IRQ_NOREQUEST);
 	P(IRQ_NOAUTOEN);

kernel/irq/manage.c

@@ -865,12 +865,10 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 			goto mismatch;
 		}
 
-#if defined(CONFIG_IRQ_PER_CPU)
 		/* All handlers must agree on per-cpuness */
 		if ((old->flags & IRQF_PERCPU) !=
 		    (new->flags & IRQF_PERCPU))
 			goto mismatch;
-#endif
 
 		/* add new interrupt at end of irq queue */
 		do {
@@ -894,15 +892,14 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 				goto out_mask;
 		} else
 			compat_irq_chip_set_default_handler(desc);
-#if defined(CONFIG_IRQ_PER_CPU)
-		if (new->flags & IRQF_PERCPU)
-			desc->status |= IRQ_PER_CPU;
-#endif
 
 		desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
 				  IRQS_INPROGRESS | IRQS_ONESHOT | \
 				  IRQS_WAITING);
 
+		if (new->flags & IRQF_PERCPU)
+			desc->status |= IRQ_PER_CPU;
+
 		if (new->flags & IRQF_ONESHOT)
 			desc->istate |= IRQS_ONESHOT;