Merge branch 'linus' into sched/core

Merge reason: update to latest upstream

Signed-off-by: Ingo Molnar <mingo@elte.hu>

6 files changed, 123 insertions, 60 deletions

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index ecc3fa28f666..b7091d5ca2f8 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -18,11 +18,7 @@
 
 #include "internals.h"
 
-/**
- *	dynamic_irq_init - initialize a dynamically allocated irq
- *	@irq:	irq number to initialize
- */
-void dynamic_irq_init(unsigned int irq)
+static void dynamic_irq_init_x(unsigned int irq, bool keep_chip_data)
 {
 	struct irq_desc *desc;
 	unsigned long flags;
@@ -41,7 +37,8 @@ void dynamic_irq_init(unsigned int irq)
 	desc->depth = 1;
 	desc->msi_desc = NULL;
 	desc->handler_data = NULL;
-	desc->chip_data = NULL;
+	if (!keep_chip_data)
+		desc->chip_data = NULL;
 	desc->action = NULL;
 	desc->irq_count = 0;
 	desc->irqs_unhandled = 0;
@@ -55,10 +52,26 @@ void dynamic_irq_init(unsigned int irq)
 }
 
 /**
- *	dynamic_irq_cleanup - cleanup a dynamically allocated irq
+ *	dynamic_irq_init - initialize a dynamically allocated irq
  *	@irq:	irq number to initialize
  */
-void dynamic_irq_cleanup(unsigned int irq)
+void dynamic_irq_init(unsigned int irq)
+{
+	dynamic_irq_init_x(irq, false);
+}
+
+/**
+ *	dynamic_irq_init_keep_chip_data - initialize a dynamically allocated irq
+ *	@irq:	irq number to initialize
+ *
+ *	does not set irq_to_desc(irq)->chip_data to NULL
+ */
+void dynamic_irq_init_keep_chip_data(unsigned int irq)
+{
+	dynamic_irq_init_x(irq, true);
+}
+
+static void dynamic_irq_cleanup_x(unsigned int irq, bool keep_chip_data)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
@@ -77,7 +90,8 @@ void dynamic_irq_cleanup(unsigned int irq)
 	}
 	desc->msi_desc = NULL;
 	desc->handler_data = NULL;
-	desc->chip_data = NULL;
+	if (!keep_chip_data)
+		desc->chip_data = NULL;
 	desc->handle_irq = handle_bad_irq;
 	desc->chip = &no_irq_chip;
 	desc->name = NULL;
@@ -85,6 +99,26 @@ void dynamic_irq_cleanup(unsigned int irq)
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 }
 
+/**
+ *	dynamic_irq_cleanup - cleanup a dynamically allocated irq
+ *	@irq:	irq number to initialize
+ */
+void dynamic_irq_cleanup(unsigned int irq)
+{
+	dynamic_irq_cleanup_x(irq, false);
+}
+
+/**
+ *	dynamic_irq_cleanup_keep_chip_data - cleanup a dynamically allocated irq
+ *	@irq:	irq number to initialize
+ *
+ *	does not set irq_to_desc(irq)->chip_data to NULL
+ */
+void dynamic_irq_cleanup_keep_chip_data(unsigned int irq)
+{
+	dynamic_irq_cleanup_x(irq, true);
+}
+
 
 /**
  *	set_irq_chip - set the irq chip for an irq
@@ -325,6 +359,23 @@ static inline void mask_ack_irq(struct irq_desc *desc, int irq)
 		if (desc->chip->ack)
 			desc->chip->ack(irq);
 	}
+	desc->status |= IRQ_MASKED;
+}
+
+static inline void mask_irq(struct irq_desc *desc, int irq)
+{
+	if (desc->chip->mask) {
+		desc->chip->mask(irq);
+		desc->status |= IRQ_MASKED;
+	}
+}
+
+static inline void unmask_irq(struct irq_desc *desc, int irq)
+{
+	if (desc->chip->unmask) {
+		desc->chip->unmask(irq);
+		desc->status &= ~IRQ_MASKED;
+	}
 }
 
 /*
@@ -450,10 +501,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
 	raw_spin_lock(&desc->lock);
 	desc->status &= ~IRQ_INPROGRESS;
 
-	if (unlikely(desc->status & IRQ_ONESHOT))
-		desc->status |= IRQ_MASKED;
-	else if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
-		desc->chip->unmask(irq);
+	if (!(desc->status & (IRQ_DISABLED | IRQ_ONESHOT)))
+		unmask_irq(desc, irq);
 out_unlock:
 	raw_spin_unlock(&desc->lock);
 }
@@ -490,8 +539,7 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
 	action = desc->action;
 	if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
 		desc->status |= IRQ_PENDING;
-		if (desc->chip->mask)
-			desc->chip->mask(irq);
+		mask_irq(desc, irq);
 		goto out;
 	}
 
@@ -520,7 +568,7 @@ out:
  *	signal. The occurence is latched into the irq controller hardware
  *	and must be acked in order to be reenabled. After the ack another
  *	interrupt can happen on the same source even before the first one
- *	is handled by the assosiacted event handler. If this happens it
+ *	is handled by the associated event handler. If this happens it
  *	might be necessary to disable (mask) the interrupt depending on the
  *	controller hardware. This requires to reenable the interrupt inside
  *	of the loop which handles the interrupts which have arrived while
@@ -559,7 +607,7 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 		irqreturn_t action_ret;
 
 		if (unlikely(!action)) {
-			desc->chip->mask(irq);
+			mask_irq(desc, irq);
 			goto out_unlock;
 		}
 
@@ -571,8 +619,7 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 		if (unlikely((desc->status &
 			       (IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) ==
 			      (IRQ_PENDING | IRQ_MASKED))) {
-			desc->chip->unmask(irq);
-			desc->status &= ~IRQ_MASKED;
+			unmask_irq(desc, irq);
 		}
 
 		desc->status &= ~IRQ_PENDING;
@@ -682,7 +729,7 @@ set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
 	__set_irq_handler(irq, handle, 0, name);
 }
 
-void __init set_irq_noprobe(unsigned int irq)
+void set_irq_noprobe(unsigned int irq)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
@@ -697,7 +744,7 @@ void __init set_irq_noprobe(unsigned int irq)
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 }
 
-void __init set_irq_probe(unsigned int irq)
+void set_irq_probe(unsigned int irq)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
diff --git a/kernel/irq/devres.c b/kernel/irq/devres.c
index d06df9c41cba..1ef4ffcdfa55 100644
--- a/kernel/irq/devres.c
+++ b/kernel/irq/devres.c
@@ -42,7 +42,7 @@ static int devm_irq_match(struct device *dev, void *res, void *data)
  *	automatically freed on driver detach.
  *
  *	If an IRQ allocated with this function needs to be freed
- *	separately, dev_free_irq() must be used.
+ *	separately, devm_free_irq() must be used.
  */
 int devm_request_threaded_irq(struct device *dev, unsigned int irq,
 			      irq_handler_t handler, irq_handler_t thread_fn,
@@ -81,7 +81,7 @@ EXPORT_SYMBOL(devm_request_threaded_irq);
  *	Except for the extra @dev argument, this function takes the
  *	same arguments and performs the same function as free_irq().
  *	This function instead of free_irq() should be used to manually
- *	free IRQs allocated with dev_request_irq().
+ *	free IRQs allocated with devm_request_irq().
  */
 void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
 {
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 814940e7f485..76d5a671bfe1 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -19,7 +19,7 @@
 #include <linux/kernel_stat.h>
 #include <linux/rculist.h>
 #include <linux/hash.h>
-#include <linux/bootmem.h>
+#include <linux/radix-tree.h>
 #include <trace/events/irq.h>
 
 #include "internals.h"
@@ -87,12 +87,8 @@ void __ref init_kstat_irqs(struct irq_desc *desc, int node, int nr)
 {
 	void *ptr;
 
-	if (slab_is_available())
-		ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs),
-				   GFP_ATOMIC, node);
-	else
-		ptr = alloc_bootmem_node(NODE_DATA(node),
-				nr * sizeof(*desc->kstat_irqs));
+	ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs),
+			   GFP_ATOMIC, node);
 
 	/*
 	 * don't overwite if can not get new one
@@ -132,7 +128,26 @@ static void init_one_irq_desc(int irq, struct irq_desc *desc, int node)
  */
 DEFINE_RAW_SPINLOCK(sparse_irq_lock);
 
-struct irq_desc **irq_desc_ptrs __read_mostly;
+static RADIX_TREE(irq_desc_tree, GFP_ATOMIC);
+
+static void set_irq_desc(unsigned int irq, struct irq_desc *desc)
+{
+	radix_tree_insert(&irq_desc_tree, irq, desc);
+}
+
+struct irq_desc *irq_to_desc(unsigned int irq)
+{
+	return radix_tree_lookup(&irq_desc_tree, irq);
+}
+
+void replace_irq_desc(unsigned int irq, struct irq_desc *desc)
+{
+	void **ptr;
+
+	ptr = radix_tree_lookup_slot(&irq_desc_tree, irq);
+	if (ptr)
+		radix_tree_replace_slot(ptr, desc);
+}
 
 static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
 	[0 ... NR_IRQS_LEGACY-1] = {
@@ -164,9 +179,6 @@ int __init early_irq_init(void)
 	legacy_count = ARRAY_SIZE(irq_desc_legacy);
 	node = first_online_node;
 
-	/* allocate irq_desc_ptrs array based on nr_irqs */
-	irq_desc_ptrs = kcalloc(nr_irqs, sizeof(void *), GFP_NOWAIT);
-
 	/* allocate based on nr_cpu_ids */
 	kstat_irqs_legacy = kzalloc_node(NR_IRQS_LEGACY * nr_cpu_ids *
 					  sizeof(int), GFP_NOWAIT, node);
@@ -180,23 +192,12 @@ int __init early_irq_init(void)
 		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
 		alloc_desc_masks(&desc[i], node, true);
 		init_desc_masks(&desc[i]);
-		irq_desc_ptrs[i] = desc + i;
+		set_irq_desc(i, &desc[i]);
 	}
 
-	for (i = legacy_count; i < nr_irqs; i++)
-		irq_desc_ptrs[i] = NULL;
-
 	return arch_early_irq_init();
 }
 
-struct irq_desc *irq_to_desc(unsigned int irq)
-{
-	if (irq_desc_ptrs && irq < nr_irqs)
-		return irq_desc_ptrs[irq];
-
-	return NULL;
-}
-
 struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
 {
 	struct irq_desc *desc;
@@ -208,21 +209,18 @@ struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
 		return NULL;
 	}
 
-	desc = irq_desc_ptrs[irq];
+	desc = irq_to_desc(irq);
 	if (desc)
 		return desc;
 
 	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
 
 	/* We have to check it to avoid races with another CPU */
-	desc = irq_desc_ptrs[irq];
+	desc = irq_to_desc(irq);
 	if (desc)
 		goto out_unlock;
 
-	if (slab_is_available())
-		desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
-	else
-		desc = alloc_bootmem_node(NODE_DATA(node), sizeof(*desc));
+	desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
 
 	printk(KERN_DEBUG "  alloc irq_desc for %d on node %d\n", irq, node);
 	if (!desc) {
@@ -231,7 +229,7 @@ struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
 	}
 	init_one_irq_desc(irq, desc, node);
 
-	irq_desc_ptrs[irq] = desc;
+	set_irq_desc(irq, desc);
 
 out_unlock:
 	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index b2821f070a3d..c63f3bc88f0b 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -21,11 +21,7 @@ extern void clear_kstat_irqs(struct irq_desc *desc);
 extern raw_spinlock_t sparse_irq_lock;
 
 #ifdef CONFIG_SPARSE_IRQ
-/* irq_desc_ptrs allocated at boot time */
-extern struct irq_desc **irq_desc_ptrs;
-#else
-/* irq_desc_ptrs is a fixed size array */
-extern struct irq_desc *irq_desc_ptrs[NR_IRQS];
+void replace_irq_desc(unsigned int irq, struct irq_desc *desc);
 #endif
 
 #ifdef CONFIG_PROC_FS
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index eb6078ca60c7..398fda155f6e 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -382,6 +382,7 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
 	struct irqaction *action;
+	unsigned long flags;
 
 	if (!desc)
 		return 0;
@@ -389,11 +390,14 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
 	if (desc->status & IRQ_NOREQUEST)
 		return 0;
 
+	raw_spin_lock_irqsave(&desc->lock, flags);
 	action = desc->action;
 	if (action)
 		if (irqflags & action->flags & IRQF_SHARED)
 			action = NULL;
 
+	raw_spin_unlock_irqrestore(&desc->lock, flags);
+
 	return !action;
 }
 
@@ -483,8 +487,26 @@ static int irq_wait_for_interrupt(struct irqaction *action)
  */
 static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc)
 {
+again:
 	chip_bus_lock(irq, desc);
 	raw_spin_lock_irq(&desc->lock);
+
+	/*
+	 * Implausible though it may be we need to protect us against
+	 * the following scenario:
+	 *
+	 * The thread is faster done than the hard interrupt handler
+	 * on the other CPU. If we unmask the irq line then the
+	 * interrupt can come in again and masks the line, leaves due
+	 * to IRQ_INPROGRESS and the irq line is masked forever.
+	 */
+	if (unlikely(desc->status & IRQ_INPROGRESS)) {
+		raw_spin_unlock_irq(&desc->lock);
+		chip_bus_sync_unlock(irq, desc);
+		cpu_relax();
+		goto again;
+	}
+
 	if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) {
 		desc->status &= ~IRQ_MASKED;
 		desc->chip->unmask(irq);
diff --git a/kernel/irq/numa_migrate.c b/kernel/irq/numa_migrate.c
index 26bac9d8f860..963559dbd858 100644
--- a/kernel/irq/numa_migrate.c
+++ b/kernel/irq/numa_migrate.c
@@ -70,7 +70,7 @@ static struct irq_desc *__real_move_irq_desc(struct irq_desc *old_desc,
 	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
 
 	/* We have to check it to avoid races with another CPU */
-	desc = irq_desc_ptrs[irq];
+	desc = irq_to_desc(irq);
 
 	if (desc && old_desc != desc)
 		goto out_unlock;
@@ -90,7 +90,7 @@ static struct irq_desc *__real_move_irq_desc(struct irq_desc *old_desc,
 		goto out_unlock;
 	}
 
-	irq_desc_ptrs[irq] = desc;
+	replace_irq_desc(irq, desc);
 	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
 
 	/* free the old one */