Merge branch 'irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (32 commits)
  x86: disable __do_IRQ support
  sparseirq, powerpc/cell: fix unused variable warning in interrupt.c
  genirq: deprecate obsolete typedefs and defines
  genirq: deprecate __do_IRQ
  genirq: add doc to struct irqaction
  genirq: use kzalloc instead of explicit zero initialization
  genirq: make irqreturn_t an enum
  genirq: remove redundant if condition
  genirq: remove unused hw_irq_controller typedef
  irq: export remove_irq() and setup_irq() symbols
  irq: match remove_irq() args with setup_irq()
  irq: add remove_irq() for freeing of setup_irq() irqs
  genirq: assert that irq handlers are indeed running in hardirq context
  irq: name 'p' variables a bit better
  irq: further clean up the free_irq() code flow
  irq: refactor and clean up the free_irq() code flow
  irq: clean up manage.c
  irq: use GFP_KERNEL for action allocation in request_irq()
  kernel/irq: fix sparse warning: make symbol static
  irq: optimize init_kstat_irqs/init_copy_kstat_irqs
  ...

6 files changed, 158 insertions, 106 deletions

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 7de11bd64df..03d0bed2b8d 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -78,6 +78,7 @@ void dynamic_irq_cleanup(unsigned int irq)
 	desc->handle_irq = handle_bad_irq;
 	desc->chip = &no_irq_chip;
 	desc->name = NULL;
+	clear_kstat_irqs(desc);
 	spin_unlock_irqrestore(&desc->lock, flags);
 }
 
@@ -290,7 +291,8 @@ static inline void mask_ack_irq(struct irq_desc *desc, int irq)
 		desc->chip->mask_ack(irq);
 	else {
 		desc->chip->mask(irq);
-		desc->chip->ack(irq);
+		if (desc->chip->ack)
+			desc->chip->ack(irq);
 	}
 }
 
@@ -476,7 +478,8 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 	kstat_incr_irqs_this_cpu(irq, desc);
 
 	/* Start handling the irq */
-	desc->chip->ack(irq);
+	if (desc->chip->ack)
+		desc->chip->ack(irq);
 	desc = irq_remap_to_desc(irq, desc);
 
 	/* Mark the IRQ currently in progress.*/
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 3aba8d12f32..f6cdda68e5c 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -83,19 +83,21 @@ static struct irq_desc irq_desc_init = {
 
 void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr)
 {
-	unsigned long bytes;
-	char *ptr;
 	int node;
-
-	/* Compute how many bytes we need per irq and allocate them */
-	bytes = nr * sizeof(unsigned int);
+	void *ptr;
 
 	node = cpu_to_node(cpu);
-	ptr = kzalloc_node(bytes, GFP_ATOMIC, node);
-	printk(KERN_DEBUG "  alloc kstat_irqs on cpu %d node %d\n", cpu, node);
+	ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs), GFP_ATOMIC, node);
 
-	if (ptr)
-		desc->kstat_irqs = (unsigned int *)ptr;
+	/*
+	 * don't overwite if can not get new one
+	 * init_copy_kstat_irqs() could still use old one
+	 */
+	if (ptr) {
+		printk(KERN_DEBUG "  alloc kstat_irqs on cpu %d node %d\n",
+			 cpu, node);
+		desc->kstat_irqs = ptr;
+	}
 }
 
 static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
@@ -227,6 +229,7 @@ struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
 	}
 };
 
+static unsigned int kstat_irqs_all[NR_IRQS][NR_CPUS];
 int __init early_irq_init(void)
 {
 	struct irq_desc *desc;
@@ -238,8 +241,10 @@ int __init early_irq_init(void)
 	desc = irq_desc;
 	count = ARRAY_SIZE(irq_desc);
 
-	for (i = 0; i < count; i++)
+	for (i = 0; i < count; i++) {
 		desc[i].irq = i;
+		desc[i].kstat_irqs = kstat_irqs_all[i];
+	}
 
 	return arch_early_irq_init();
 }
@@ -255,6 +260,11 @@ struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
 }
 #endif /* !CONFIG_SPARSE_IRQ */
 
+void clear_kstat_irqs(struct irq_desc *desc)
+{
+	memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
+}
+
 /*
  * What should we do if we get a hw irq event on an illegal vector?
  * Each architecture has to answer this themself.
@@ -328,6 +338,8 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
 	irqreturn_t ret, retval = IRQ_NONE;
 	unsigned int status = 0;
 
+	WARN_ONCE(!in_irq(), "BUG: IRQ handler called from non-hardirq context!");
+
 	if (!(action->flags & IRQF_DISABLED))
 		local_irq_enable_in_hardirq();
 
@@ -347,6 +359,11 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
 }
 
 #ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
+
+#ifdef CONFIG_ENABLE_WARN_DEPRECATED
+# warning __do_IRQ is deprecated. Please convert to proper flow handlers
+#endif
+
 /**
  * __do_IRQ - original all in one highlevel IRQ handler
  * @irq:	the interrupt number
@@ -467,12 +484,10 @@ void early_init_irq_lock_class(void)
 	}
 }
 
-#ifdef CONFIG_SPARSE_IRQ
 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
 	return desc ? desc->kstat_irqs[cpu] : 0;
 }
-#endif
 EXPORT_SYMBOL(kstat_irqs_cpu);
 
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index e6d0a43cc12..b60950bf5a1 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -15,6 +15,7 @@ extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
 
 extern struct lock_class_key irq_desc_lock_class;
 extern void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr);
+extern void clear_kstat_irqs(struct irq_desc *desc);
 extern spinlock_t sparse_irq_lock;
 extern struct irq_desc *irq_desc_ptrs[NR_IRQS];
 
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 291f0366455..ea119effe09 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -109,7 +109,7 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
 /*
  * Generic version of the affinity autoselector.
  */
-int do_irq_select_affinity(unsigned int irq, struct irq_desc *desc)
+static int setup_affinity(unsigned int irq, struct irq_desc *desc)
 {
 	if (!irq_can_set_affinity(irq))
 		return 0;
@@ -133,7 +133,7 @@ set_affinity:
 	return 0;
 }
 #else
-static inline int do_irq_select_affinity(unsigned int irq, struct irq_desc *d)
+static inline int setup_affinity(unsigned int irq, struct irq_desc *d)
 {
 	return irq_select_affinity(irq);
 }
@@ -149,14 +149,14 @@ int irq_select_affinity_usr(unsigned int irq)
 	int ret;
 
 	spin_lock_irqsave(&desc->lock, flags);
-	ret = do_irq_select_affinity(irq, desc);
+	ret = setup_affinity(irq, desc);
 	spin_unlock_irqrestore(&desc->lock, flags);
 
 	return ret;
 }
 
 #else
-static inline int do_irq_select_affinity(int irq, struct irq_desc *desc)
+static inline int setup_affinity(unsigned int irq, struct irq_desc *desc)
 {
 	return 0;
 }
@@ -389,9 +389,9 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
  * allocate special interrupts that are part of the architecture.
  */
 static int
-__setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
+__setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 {
-	struct irqaction *old, **p;
+	struct irqaction *old, **old_ptr;
 	const char *old_name = NULL;
 	unsigned long flags;
 	int shared = 0;
@@ -423,8 +423,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
 	 * The following block of code has to be executed atomically
 	 */
 	spin_lock_irqsave(&desc->lock, flags);
-	p = &desc->action;
-	old = *p;
+	old_ptr = &desc->action;
+	old = *old_ptr;
 	if (old) {
 		/*
 		 * Can't share interrupts unless both agree to and are
@@ -447,8 +447,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
 
 		/* add new interrupt at end of irq queue */
 		do {
-			p = &old->next;
-			old = *p;
+			old_ptr = &old->next;
+			old = *old_ptr;
 		} while (old);
 		shared = 1;
 	}
@@ -488,7 +488,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
 			desc->status |= IRQ_NO_BALANCING;
 
 		/* Set default affinity mask once everything is setup */
-		do_irq_select_affinity(irq, desc);
+		setup_affinity(irq, desc);
 
 	} else if ((new->flags & IRQF_TRIGGER_MASK)
 			&& (new->flags & IRQF_TRIGGER_MASK)
@@ -499,7 +499,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
 				(int)(new->flags & IRQF_TRIGGER_MASK));
 	}
 
-	*p = new;
+	*old_ptr = new;
 
 	/* Reset broken irq detection when installing new handler */
 	desc->irq_count = 0;
@@ -549,90 +549,117 @@ int setup_irq(unsigned int irq, struct irqaction *act)
 
 	return __setup_irq(irq, desc, act);
 }
+EXPORT_SYMBOL_GPL(setup_irq);
 
-/**
- *	free_irq - free an interrupt
- *	@irq: Interrupt line to free
- *	@dev_id: Device identity to free
- *
- *	Remove an interrupt handler. The handler is removed and if the
- *	interrupt line is no longer in use by any driver it is disabled.
- *	On a shared IRQ the caller must ensure the interrupt is disabled
- *	on the card it drives before calling this function. The function
- *	does not return until any executing interrupts for this IRQ
- *	have completed.
- *
- *	This function must not be called from interrupt context.
+ /*
+ * Internal function to unregister an irqaction - used to free
+ * regular and special interrupts that are part of the architecture.
  */
-void free_irq(unsigned int irq, void *dev_id)
+static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
-	struct irqaction **p;
+	struct irqaction *action, **action_ptr;
 	unsigned long flags;
 
-	WARN_ON(in_interrupt());
+	WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
 
 	if (!desc)
-		return;
+		return NULL;
 
 	spin_lock_irqsave(&desc->lock, flags);
-	p = &desc->action;
+
+	/*
+	 * There can be multiple actions per IRQ descriptor, find the right
+	 * one based on the dev_id:
+	 */
+	action_ptr = &desc->action;
 	for (;;) {
-		struct irqaction *action = *p;
+		action = *action_ptr;
 
-		if (action) {
-			struct irqaction **pp = p;
+		if (!action) {
+			WARN(1, "Trying to free already-free IRQ %d\n", irq);
+			spin_unlock_irqrestore(&desc->lock, flags);
 
-			p = &action->next;
-			if (action->dev_id != dev_id)
-				continue;
+			return NULL;
+		}
 
-			/* Found it - now remove it from the list of entries */
-			*pp = action->next;
+		if (action->dev_id == dev_id)
+			break;
+		action_ptr = &action->next;
+	}
 
-			/* Currently used only by UML, might disappear one day.*/
+	/* Found it - now remove it from the list of entries: */
+	*action_ptr = action->next;
+
+	/* Currently used only by UML, might disappear one day: */
 #ifdef CONFIG_IRQ_RELEASE_METHOD
-			if (desc->chip->release)
-				desc->chip->release(irq, dev_id);
+	if (desc->chip->release)
+		desc->chip->release(irq, dev_id);
 #endif
 
-			if (!desc->action) {
-				desc->status |= IRQ_DISABLED;
-				if (desc->chip->shutdown)
-					desc->chip->shutdown(irq);
-				else
-					desc->chip->disable(irq);
-			}
-			spin_unlock_irqrestore(&desc->lock, flags);
-			unregister_handler_proc(irq, action);
+	/* If this was the last handler, shut down the IRQ line: */
+	if (!desc->action) {
+		desc->status |= IRQ_DISABLED;
+		if (desc->chip->shutdown)
+			desc->chip->shutdown(irq);
+		else
+			desc->chip->disable(irq);
+	}
+	spin_unlock_irqrestore(&desc->lock, flags);
+
+	unregister_handler_proc(irq, action);
+
+	/* Make sure it's not being used on another CPU: */
+	synchronize_irq(irq);
 
-			/* Make sure it's not being used on another CPU */
-			synchronize_irq(irq);
-#ifdef CONFIG_DEBUG_SHIRQ
-			/*
-			 * It's a shared IRQ -- the driver ought to be
-			 * prepared for it to happen even now it's
-			 * being freed, so let's make sure....  We do
-			 * this after actually deregistering it, to
-			 * make sure that a 'real' IRQ doesn't run in
-			 * parallel with our fake
-			 */
-			if (action->flags & IRQF_SHARED) {
-				local_irq_save(flags);
-				action->handler(irq, dev_id);
-				local_irq_restore(flags);
-			}
-#endif
-			kfree(action);
-			return;
-		}
-		printk(KERN_ERR "Trying to free already-free IRQ %d\n", irq);
 #ifdef CONFIG_DEBUG_SHIRQ
-		dump_stack();
-#endif
-		spin_unlock_irqrestore(&desc->lock, flags);
-		return;
+	/*
+	 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
+	 * event to happen even now it's being freed, so let's make sure that
+	 * is so by doing an extra call to the handler ....
+	 *
+	 * ( We do this after actually deregistering it, to make sure that a
+	 *   'real' IRQ doesn't run in * parallel with our fake. )
+	 */
+	if (action->flags & IRQF_SHARED) {
+		local_irq_save(flags);
+		action->handler(irq, dev_id);
+		local_irq_restore(flags);
 	}
+#endif
+	return action;
+}
+
+/**
+ *	remove_irq - free an interrupt
+ *	@irq: Interrupt line to free
+ *	@act: irqaction for the interrupt
+ *
+ * Used to remove interrupts statically setup by the early boot process.
+ */
+void remove_irq(unsigned int irq, struct irqaction *act)
+{
+	__free_irq(irq, act->dev_id);
+}
+EXPORT_SYMBOL_GPL(remove_irq);
+
+/**
+ *	free_irq - free an interrupt allocated with request_irq
+ *	@irq: Interrupt line to free
+ *	@dev_id: Device identity to free
+ *
+ *	Remove an interrupt handler. The handler is removed and if the
+ *	interrupt line is no longer in use by any driver it is disabled.
+ *	On a shared IRQ the caller must ensure the interrupt is disabled
+ *	on the card it drives before calling this function. The function
+ *	does not return until any executing interrupts for this IRQ
+ *	have completed.
+ *
+ *	This function must not be called from interrupt context.
+ */
+void free_irq(unsigned int irq, void *dev_id)
+{
+	kfree(__free_irq(irq, dev_id));
 }
 EXPORT_SYMBOL(free_irq);
 
@@ -679,11 +706,12 @@ int request_irq(unsigned int irq, irq_handler_t handler,
 	 * the behavior is classified as "will not fix" so we need to
 	 * start nudging drivers away from using that idiom.
 	 */
-	if ((irqflags & (IRQF_SHARED|IRQF_DISABLED))
-			== (IRQF_SHARED|IRQF_DISABLED))
-		pr_warning("IRQ %d/%s: IRQF_DISABLED is not "
-				"guaranteed on shared IRQs\n",
-				irq, devname);
+	if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) ==
+					(IRQF_SHARED|IRQF_DISABLED)) {
+		pr_warning(
+		  "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
+			irq, devname);
+	}
 
 #ifdef CONFIG_LOCKDEP
 	/*
@@ -709,15 +737,13 @@ int request_irq(unsigned int irq, irq_handler_t handler,
 	if (!handler)
 		return -EINVAL;
 
-	action = kmalloc(sizeof(struct irqaction), GFP_ATOMIC);
+	action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
 	if (!action)
 		return -ENOMEM;
 
 	action->handler = handler;
 	action->flags = irqflags;
-	cpus_clear(action->mask);
 	action->name = devname;
-	action->next = NULL;
 	action->dev_id = dev_id;
 
 	retval = __setup_irq(irq, desc, action);
diff --git a/kernel/irq/numa_migrate.c b/kernel/irq/numa_migrate.c
index acd88356ac7..aef18ab6b75 100644
--- a/kernel/irq/numa_migrate.c
+++ b/kernel/irq/numa_migrate.c
@@ -17,16 +17,11 @@ static void init_copy_kstat_irqs(struct irq_desc *old_desc,
 				 struct irq_desc *desc,
 				 int cpu, int nr)
 {
-	unsigned long bytes;
-
 	init_kstat_irqs(desc, cpu, nr);
 
-	if (desc->kstat_irqs != old_desc->kstat_irqs) {
-		/* Compute how many bytes we need per irq and allocate them */
-		bytes = nr * sizeof(unsigned int);
-
-		memcpy(desc->kstat_irqs, old_desc->kstat_irqs, bytes);
-	}
+	if (desc->kstat_irqs != old_desc->kstat_irqs)
+		memcpy(desc->kstat_irqs, old_desc->kstat_irqs,
+			 nr * sizeof(*desc->kstat_irqs));
 }
 
 static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index dd364c11e56..4d568294de3 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -104,7 +104,7 @@ static int misrouted_irq(int irq)
 	return ok;
 }
 
-static void poll_spurious_irqs(unsigned long dummy)
+static void poll_all_shared_irqs(void)
 {
 	struct irq_desc *desc;
 	int i;
@@ -123,11 +123,23 @@ static void poll_spurious_irqs(unsigned long dummy)
 
 		try_one_irq(i, desc);
 	}
+}
+
+static void poll_spurious_irqs(unsigned long dummy)
+{
+	poll_all_shared_irqs();
 
 	mod_timer(&poll_spurious_irq_timer,
 		  jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
 }
 
+#ifdef CONFIG_DEBUG_SHIRQ
+void debug_poll_all_shared_irqs(void)
+{
+	poll_all_shared_irqs();
+}
+#endif
+
 /*
  * If 99,900 of the previous 100,000 interrupts have not been handled
  * then assume that the IRQ is stuck in some manner. Drop a diagnostic