[PATCH 1/3] Delete unused irq functions on powerpc

[PATCH 1/3] Delete unused irq functions on powerpc

[Matthew Wilcox]

The ack_irq macro is unused and conflicts with James' work to template
the generic irq code.  mask_irq and unmask_irq are also unused, so delete
those macros too.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
---
 include/asm-powerpc/hw_irq.h |   19 -------------------
 1 files changed, 0 insertions(+), 19 deletions(-)

diff --git a/include/asm-powerpc/hw_irq.h b/include/asm-powerpc/hw_irq.h
index d604863..9e4dd98 100644
--- a/include/asm-powerpc/hw_irq.h
+++ b/include/asm-powerpc/hw_irq.h
@@ -107,25 +107,6 @@ static inline void local_irq_save_ptr(un
 
 #endif /* CONFIG_PPC64 */
 
-#define mask_irq(irq)						\
-	({							\
-	 	irq_desc_t *desc = get_irq_desc(irq);		\
-		if (desc->chip && desc->chip->disable)	\
-			desc->chip->disable(irq);		\
-	})
-#define unmask_irq(irq)						\
-	({							\
-	 	irq_desc_t *desc = get_irq_desc(irq);		\
-		if (desc->chip && desc->chip->enable)	\
-			desc->chip->enable(irq);		\
-	})
-#define ack_irq(irq)						\
-	({							\
-	 	irq_desc_t *desc = get_irq_desc(irq);		\
-		if (desc->chip && desc->chip->ack)	\
-			desc->chip->ack(irq);		\
-	})
-
 /*
  * interrupt-retrigger: should we handle this via lost interrupts and IPIs
  * or should we not care like we do now ? --BenH.
-- 
1.4.3.3

[PATCH 2/3] Add the ability to template irq handlers in the generic irq code

[Matthew Wilcox]

On parisc, we have the issue that function call pointers are hugely
expensive, so we'd like to minimise their use in the interrupts.
Unfortunately, this involves directly calling the ack/eoi functions
instead of indirecting.  To permit this without losing the advantages of
centrally managed irq code, I introduced template builders for irq
handlers.  This allows us to construct special handlers on parisc that
don't indirect through function call pointers.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

Some fixes by Andrew Morton and Matthew Wilcox due to rapid code flux
in this area.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
---
 kernel/irq/chip.c |  163 ++++++++++++++++++++++++++++++++++-------------------
 1 files changed, 104 insertions(+), 59 deletions(-)

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index ebfd24a..1b18c5c 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -17,6 +17,87 @@
 
 #include "internals.h"
 
+/* Helpers for constructing IRQ handlers */
+
+#ifdef CONFIG_SMP
+#define HANDLE_PERCPU_IRQ(NAME, ACK, EOI)				\
+void fastcall								\
+handle_percpu_irq##NAME(unsigned int irq, struct irq_desc *desc)	\
+{									\
+	irqreturn_t action_ret;						\
+									\
+	kstat_this_cpu.irqs[irq]++;					\
+									\
+	ACK(desc, irq);							\
+									\
+	action_ret = handle_IRQ_event(irq, desc->action);		\
+	if (!noirqdebug)						\
+		note_interrupt(irq, desc, action_ret);			\
+									\
+	EOI(desc,irq);							\
+}
+#else
+#define HANDLE_PERCPU_IRQ(NAME, ACK, END)
+#endif /* CONFIG_SMP */
+
+#define HANDLE_LEVEL_IRQ(NAME, MASK, UNMASK)				\
+void fastcall								\
+handle_level_irq##NAME(unsigned int irq, struct irq_desc *desc)		\
+{									\
+	unsigned int cpu = smp_processor_id();				\
+	struct irqaction *action;					\
+	irqreturn_t action_ret;						\
+									\
+	spin_lock(&desc->lock);						\
+	MASK(desc, irq);						\
+									\
+	if (unlikely(desc->status & IRQ_INPROGRESS))			\
+		goto out_unlock;					\
+	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);			\
+	kstat_cpu(cpu).irqs[irq]++;					\
+									\
+	/*								\
+	 * If its disabled or no action available			\
+	 * keep it masked and get out of here				\
+	 */								\
+	action = desc->action;						\
+	if (unlikely(!action || (desc->status & IRQ_DISABLED))) {	\
+		desc->status |= IRQ_PENDING;				\
+		goto out_unlock;					\
+	}								\
+									\
+	desc->status |= IRQ_INPROGRESS;					\
+	desc->status &= ~IRQ_PENDING;					\
+	spin_unlock(&desc->lock);					\
+									\
+	action_ret = handle_IRQ_event(irq, action);			\
+	if (!noirqdebug)						\
+		note_interrupt(irq, desc, action_ret);			\
+									\
+	spin_lock(&desc->lock);						\
+	desc->status &= ~IRQ_INPROGRESS;				\
+	UNMASK(desc,irq);						\
+out_unlock:								\
+	spin_unlock(&desc->lock);					\
+}
+
+#define HANDLE_SPECIFIC_IRQ(NAME, ACK, EOI, HANDLER)			\
+void fastcall								\
+handle_specific_irq##NAME(unsigned int irq, struct irq_desc *desc)	\
+{									\
+	irqreturn_t action_ret;						\
+									\
+	kstat_this_cpu.irqs[irq]++;					\
+									\
+	ACK(desc, irq);							\
+									\
+	action_ret = HANDLER(irq, desc->action->dev_id);		\
+	if (!noirqdebug)						\
+		note_interrupt(irq, desc, action_ret);			\
+									\
+	EOI(desc,irq);							\
+}
+
 /**
  *	dynamic_irq_init - initialize a dynamically allocated irq
  *	@irq:	irq number to initialize
@@ -247,6 +328,24 @@ static inline void mask_ack_irq(struct i
 	}
 }
 
+static inline void unmask_enabled_irq(struct irq_desc *desc, int irq)
+{
+	if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
+		desc->chip->unmask(irq);
+}
+
+static inline void ack_irq(struct irq_desc *desc, int irq)
+{
+	if (desc->chip->ack)
+		desc->chip->ack(irq);
+}
+
+static inline void eoi_irq(struct irq_desc *desc, int irq)
+{
+	if (desc->chip->eoi)
+		desc->chip->eoi(irq);
+}
+
 /**
  *	handle_simple_irq - Simple and software-decoded IRQs.
  *	@irq:	the interrupt number
@@ -300,46 +399,7 @@ out_unlock:
  *	it after the associated handler has acknowledged the device, so the
  *	interrupt line is back to inactive.
  */
-void fastcall
-handle_level_irq(unsigned int irq, struct irq_desc *desc)
-{
-	unsigned int cpu = smp_processor_id();
-	struct irqaction *action;
-	irqreturn_t action_ret;
-
-	spin_lock(&desc->lock);
-	mask_ack_irq(desc, irq);
-
-	if (unlikely(desc->status & IRQ_INPROGRESS))
-		goto out_unlock;
-	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
-	kstat_cpu(cpu).irqs[irq]++;
-
-	/*
-	 * If its disabled or no action available
-	 * keep it masked and get out of here
-	 */
-	action = desc->action;
-	if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
-		desc->status |= IRQ_PENDING;
-		goto out_unlock;
-	}
-
-	desc->status |= IRQ_INPROGRESS;
-	desc->status &= ~IRQ_PENDING;
-	spin_unlock(&desc->lock);
-
-	action_ret = handle_IRQ_event(irq, action);
-	if (!noirqdebug)
-		note_interrupt(irq, desc, action_ret);
-
-	spin_lock(&desc->lock);
-	desc->status &= ~IRQ_INPROGRESS;
-	if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
-		desc->chip->unmask(irq);
-out_unlock:
-	spin_unlock(&desc->lock);
-}
+HANDLE_LEVEL_IRQ(, mask_ack_irq, unmask_enabled_irq)
 
 /**
  *	handle_fasteoi_irq - irq handler for transparent controllers
@@ -472,7 +532,6 @@ out_unlock:
 	spin_unlock(&desc->lock);
 }
 
-#ifdef CONFIG_SMP
 /**
  *	handle_percpu_IRQ - Per CPU local irq handler
  *	@irq:	the interrupt number
@@ -480,25 +539,11 @@ out_unlock:
  *
  *	Per CPU interrupts on SMP machines without locking requirements
  */
-void fastcall
-handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
-{
-	irqreturn_t action_ret;
-
-	kstat_this_cpu.irqs[irq]++;
-
-	if (desc->chip->ack)
-		desc->chip->ack(irq);
+HANDLE_PERCPU_IRQ(, ack_irq, eoi_irq)
 
-	action_ret = handle_IRQ_event(irq, desc->action);
-	if (!noirqdebug)
-		note_interrupt(irq, desc, action_ret);
-
-	if (desc->chip->eoi)
-		desc->chip->eoi(irq);
-}
-
-#endif /* CONFIG_SMP */
+#ifdef ARCH_HAS_IRQ_HANDLERS
+#include <asm/irq-handlers.h>
+#endif
 
 void
 __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
-- 
1.4.3.3

[PATCH 3/3] Convert parisc to generic irq handling

[Matthew Wilcox]

Also make use of the specific ability to template interrupts for the
timer and IPI interrupts.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

Updated for pt_regs changes

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
---
 arch/parisc/kernel/irq.c          |   23 ++++++++++-------------
 drivers/parisc/iosapic.c          |    7 +++----
 include/asm-parisc/irq-handlers.h |   15 +++++++++++++++
 include/asm-parisc/irq.h          |   21 +++++++++++++++++++--
 4 files changed, 47 insertions(+), 19 deletions(-)

diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c
index b39c5b9..2a929a2 100644
--- a/arch/parisc/kernel/irq.c
+++ b/arch/parisc/kernel/irq.c
@@ -35,9 +35,6 @@
 
 #undef PARISC_IRQ_CR16_COUNTS
 
-extern irqreturn_t timer_interrupt(int, void *);
-extern irqreturn_t ipi_interrupt(int, void *);
-
 #define EIEM_MASK(irq)       (1UL<<(CPU_IRQ_MAX - irq))
 
 /* Bits in EIEM correlate with cpu_irq_action[].
@@ -88,7 +85,7 @@ static unsigned int cpu_startup_irq(unsi
 void no_ack_irq(unsigned int irq) { }
 void no_end_irq(unsigned int irq) { }
 
-void cpu_ack_irq(unsigned int irq)
+void cpu_ack_irq(struct irq_desc *dummy, unsigned int irq)
 {
 	unsigned long mask = EIEM_MASK(irq);
 	int cpu = smp_processor_id();
@@ -105,7 +102,7 @@ void cpu_ack_irq(unsigned int irq)
 	mtctl(mask, 23);
 }
 
-void cpu_end_irq(unsigned int irq)
+void cpu_end_irq(struct irq_desc *dummy, unsigned int irq)
 {
 	unsigned long mask = EIEM_MASK(irq);
 	int cpu = smp_processor_id();
@@ -155,8 +152,6 @@ static struct hw_interrupt_type cpu_inte
 	.shutdown	= cpu_disable_irq,
 	.enable		= cpu_enable_irq,
 	.disable	= cpu_disable_irq,
-	.ack		= cpu_ack_irq,
-	.end		= cpu_end_irq,
 #ifdef CONFIG_SMP
 	.set_affinity	= cpu_set_affinity_irq,
 #endif
@@ -253,8 +248,8 @@ int cpu_claim_irq(unsigned int irq, stru
 		return -EBUSY;
 
 	if (type) {
-		irq_desc[irq].chip = type;
-		irq_desc[irq].chip_data = data;
+		set_irq_chip(irq, type);
+		set_irq_chip_data(irq, data);
 		cpu_interrupt_type.enable(irq);
 	}
 	return 0;
@@ -377,7 +372,7 @@ void do_cpu_irq_mask(struct pt_regs *reg
 		goto set_out;
 	}
 #endif
-	__do_IRQ(irq);
+	generic_handle_irq(irq);
 
  out:
 	irq_exit();
@@ -406,15 +401,17 @@ static struct irqaction ipi_action = {
 static void claim_cpu_irqs(void)
 {
 	int i;
-	for (i = CPU_IRQ_BASE; i <= CPU_IRQ_MAX; i++) {
-		irq_desc[i].chip = &cpu_interrupt_type;
-	}
+	for (i = CPU_IRQ_BASE; i <= CPU_IRQ_MAX; i++)
+		set_irq_chip_and_handler(i, &cpu_interrupt_type,
+					 handle_level_irq_chip);
 
 	irq_desc[TIMER_IRQ].action = &timer_action;
 	irq_desc[TIMER_IRQ].status |= IRQ_PER_CPU;
+	set_irq_handler(TIMER_IRQ, handle_specific_irq_timer);
 #ifdef CONFIG_SMP
 	irq_desc[IPI_IRQ].action = &ipi_action;
 	irq_desc[IPI_IRQ].status = IRQ_PER_CPU;
+	set_irq_handler(IPI_IRQ, handle_specific_irq_ipi);
 #endif
 }
 
diff --git a/drivers/parisc/iosapic.c b/drivers/parisc/iosapic.c
index 12bab64..4e9f660 100644
--- a/drivers/parisc/iosapic.c
+++ b/drivers/parisc/iosapic.c
@@ -686,13 +686,13 @@ printk("\n");
  * i386/ia64 support ISA devices and have to deal with
  * edge-triggered interrupts too.
  */
-static void iosapic_end_irq(unsigned int irq)
+void iosapic_end_irq(struct irq_desc *dummy, unsigned int irq)
 {
 	struct vector_info *vi = iosapic_get_vector(irq);
 	DBG(KERN_DEBUG "end_irq(%d): eoi(%p, 0x%x)\n", irq,
 			vi->eoi_addr, vi->eoi_data);
 	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
-	cpu_end_irq(irq);
+	cpu_end_irq(NULL, irq);
 }
 
 static unsigned int iosapic_startup_irq(unsigned int irq)
@@ -729,8 +729,6 @@ static struct hw_interrupt_type iosapic_
 	.shutdown =	iosapic_disable_irq,
 	.enable =	iosapic_enable_irq,
 	.disable =	iosapic_disable_irq,
-	.ack =		cpu_ack_irq,
-	.end =		iosapic_end_irq,
 #ifdef CONFIG_SMP
 	.set_affinity =	iosapic_set_affinity_irq,
 #endif
@@ -819,6 +817,7 @@ int iosapic_fixup_irq(void *isi_obj, str
 	vi->eoi_data = cpu_to_le32(vi->txn_data);
 
 	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
+	set_irq_handler(vi->txn_irq, handle_level_irq_iosapic);
 
  out:
 	pcidev->irq = vi->txn_irq;
diff --git a/include/asm-parisc/irq-handlers.h b/include/asm-parisc/irq-handlers.h
new file mode 100644
index 0000000..95a9d1b
--- /dev/null
+++ b/include/asm-parisc/irq-handlers.h
@@ -0,0 +1,8 @@
+HANDLE_LEVEL_IRQ(_chip, cpu_ack_irq, cpu_end_irq)
+HANDLE_SPECIFIC_IRQ(_timer, cpu_ack_irq, cpu_end_irq, timer_interrupt)
+#ifdef CONFIG_SMP
+HANDLE_SPECIFIC_IRQ(_ipi, cpu_ack_irq, cpu_end_irq, ipi_interrupt)
+#endif
+#ifdef CONFIG_IOSAPIC
+HANDLE_LEVEL_IRQ(_iosapic, cpu_ack_irq, iosapic_end_irq)
+#endif
diff --git a/include/asm-parisc/irq.h b/include/asm-parisc/irq.h
index 399c819..ae29629 100644
--- a/include/asm-parisc/irq.h
+++ b/include/asm-parisc/irq.h
@@ -8,6 +8,7 @@
 #define _ASM_PARISC_IRQ_H
 
 #include <linux/cpumask.h>
+#include <linux/irqreturn.h>
 #include <asm/types.h>
 
 #define NO_IRQ		(-1)
@@ -26,6 +27,17 @@
 
 #define NR_IRQS		(CPU_IRQ_MAX + 1)
 
+#define ARCH_HAS_IRQ_HANDLERS
+
+struct irq_desc;
+
+void fastcall handle_level_irq_chip(unsigned int irq, struct irq_desc *desc);
+void fastcall handle_level_irq_iosapic(unsigned int irq, struct irq_desc *desc);
+void fastcall handle_percpu_irq_chip(unsigned int irq, struct irq_desc *desc);
+void fastcall handle_specific_irq_timer(unsigned int irq,
+					struct irq_desc *desc);
+void fastcall handle_specific_irq_ipi(unsigned int irq, struct irq_desc *desc);
+
 static __inline__ int irq_canonicalize(int irq)
 {
 	return (irq == 2) ? 9 : irq;
@@ -39,8 +51,9 @@ struct irq_chip;
  */
 void no_ack_irq(unsigned int irq);
 void no_end_irq(unsigned int irq);
-void cpu_ack_irq(unsigned int irq);
-void cpu_end_irq(unsigned int irq);
+void cpu_ack_irq(struct irq_desc *, unsigned int irq);
+void cpu_end_irq(struct irq_desc *, unsigned int irq);
+void iosapic_end_irq(struct irq_desc *, unsigned int irq);
 
 extern int txn_alloc_irq(unsigned int nbits);
 extern int txn_claim_irq(int);
@@ -51,6 +64,10 @@ extern unsigned long txn_affinity_addr(u
 extern int cpu_claim_irq(unsigned int irq, struct irq_chip *, void *);
 extern int cpu_check_affinity(unsigned int irq, cpumask_t *dest);
 
+/* Prototypes for the two directly called interrupts */
+extern irqreturn_t timer_interrupt(int, void *);
+extern irqreturn_t ipi_interrupt(int, void *);
+
 /* soft power switch support (power.c) */
 extern struct tasklet_struct power_tasklet;
 
-- 
1.4.3.3