/*
* linux/kernel/irq/handle.c
*
- * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
+ * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
+ * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
*
* This file contains the core interrupt handling code.
+ *
+ * Detailed information is available in Documentation/DocBook/genericirq
+ *
*/
#include <linux/irq.h>
#include <linux/random.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
+#include <linux/rculist.h>
+#include <linux/hash.h>
#include "internals.h"
+/*
+ * lockdep: we want to handle all irq_desc locks as a single lock-class:
+ */
+struct lock_class_key irq_desc_lock_class;
+
+/**
+ * handle_bad_irq - handle spurious and unhandled irqs
+ * @irq: the interrupt number
+ * @desc: description of the interrupt
+ *
+ * Handles spurious and unhandled IRQ's. It also prints a debugmessage.
+ */
+void handle_bad_irq(unsigned int irq, struct irq_desc *desc)
+{
+ print_irq_desc(irq, desc);
+ kstat_incr_irqs_this_cpu(irq, desc);
+ ack_bad_irq(irq);
+}
+
/*
* Linux has a controller-independent interrupt architecture.
* Every controller has a 'controller-template', that is used
* by the main code to do the right thing. Each driver-visible
- * interrupt source is transparently wired to the apropriate
+ * interrupt source is transparently wired to the appropriate
* controller. Thus drivers need not be aware of the
* interrupt-controller.
*
*
* Controller mappings for all interrupt sources:
*/
-irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned = {
+int nr_irqs = NR_IRQS;
+EXPORT_SYMBOL_GPL(nr_irqs);
+
+#ifdef CONFIG_SPARSE_IRQ
+static struct irq_desc irq_desc_init = {
+ .irq = -1,
+ .status = IRQ_DISABLED,
+ .chip = &no_irq_chip,
+ .handle_irq = handle_bad_irq,
+ .depth = 1,
+ .lock = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
+#ifdef CONFIG_SMP
+ .affinity = CPU_MASK_ALL
+#endif
+};
+
+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);
+
+ 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);
+
+ if (ptr)
+ desc->kstat_irqs = (unsigned int *)ptr;
+}
+
+static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
+{
+ memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));
+
+ spin_lock_init(&desc->lock);
+ desc->irq = irq;
+#ifdef CONFIG_SMP
+ desc->cpu = cpu;
+#endif
+ lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+ init_kstat_irqs(desc, cpu, nr_cpu_ids);
+ if (!desc->kstat_irqs) {
+ printk(KERN_ERR "can not alloc kstat_irqs\n");
+ BUG_ON(1);
+ }
+ arch_init_chip_data(desc, cpu);
+}
+
+/*
+ * Protect the sparse_irqs:
+ */
+DEFINE_SPINLOCK(sparse_irq_lock);
+
+struct irq_desc *irq_desc_ptrs[NR_IRQS] __read_mostly;
+
+static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
+ [0 ... NR_IRQS_LEGACY-1] = {
+ .irq = -1,
+ .status = IRQ_DISABLED,
+ .chip = &no_irq_chip,
+ .handle_irq = handle_bad_irq,
+ .depth = 1,
+ .lock = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
+#ifdef CONFIG_SMP
+ .affinity = CPU_MASK_ALL
+#endif
+ }
+};
+
+/* FIXME: use bootmem alloc ...*/
+static unsigned int kstat_irqs_legacy[NR_IRQS_LEGACY][NR_CPUS];
+
+int __init early_irq_init(void)
+{
+ struct irq_desc *desc;
+ int legacy_count;
+ int i;
+
+ desc = irq_desc_legacy;
+ legacy_count = ARRAY_SIZE(irq_desc_legacy);
+
+ for (i = 0; i < legacy_count; i++) {
+ desc[i].irq = i;
+ desc[i].kstat_irqs = kstat_irqs_legacy[i];
+ lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
+
+ irq_desc_ptrs[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)
+{
+ return (irq < NR_IRQS) ? irq_desc_ptrs[irq] : NULL;
+}
+
+struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
+{
+ struct irq_desc *desc;
+ unsigned long flags;
+ int node;
+
+ if (irq >= NR_IRQS) {
+ printk(KERN_WARNING "irq >= NR_IRQS in irq_to_desc_alloc: %d %d\n",
+ irq, NR_IRQS);
+ WARN_ON(1);
+ return NULL;
+ }
+
+ desc = irq_desc_ptrs[irq];
+ if (desc)
+ return desc;
+
+ spin_lock_irqsave(&sparse_irq_lock, flags);
+
+ /* We have to check it to avoid races with another CPU */
+ desc = irq_desc_ptrs[irq];
+ if (desc)
+ goto out_unlock;
+
+ node = cpu_to_node(cpu);
+ desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
+ printk(KERN_DEBUG " alloc irq_desc for %d on cpu %d node %d\n",
+ irq, cpu, node);
+ if (!desc) {
+ printk(KERN_ERR "can not alloc irq_desc\n");
+ BUG_ON(1);
+ }
+ init_one_irq_desc(irq, desc, cpu);
+
+ irq_desc_ptrs[irq] = desc;
+
+out_unlock:
+ spin_unlock_irqrestore(&sparse_irq_lock, flags);
+
+ return desc;
+}
+
+#else /* !CONFIG_SPARSE_IRQ */
+
+struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
[0 ... NR_IRQS-1] = {
.status = IRQ_DISABLED,
- .chip = &no_irq_type,
- .lock = SPIN_LOCK_UNLOCKED
+ .chip = &no_irq_chip,
+ .handle_irq = handle_bad_irq,
+ .depth = 1,
+ .lock = __SPIN_LOCK_UNLOCKED(irq_desc->lock),
+#ifdef CONFIG_SMP
+ .affinity = CPU_MASK_ALL
+#endif
}
};
+int __init early_irq_init(void)
+{
+ struct irq_desc *desc;
+ int count;
+ int i;
+
+ desc = irq_desc;
+ count = ARRAY_SIZE(irq_desc);
+
+ for (i = 0; i < count; i++)
+ desc[i].irq = i;
+
+ return arch_early_irq_init();
+}
+
+struct irq_desc *irq_to_desc(unsigned int irq)
+{
+ return (irq < NR_IRQS) ? irq_desc + irq : NULL;
+}
+
+struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
+{
+ return irq_to_desc(irq);
+}
+#endif /* !CONFIG_SPARSE_IRQ */
+
/*
- * Generic 'no controller' code
+ * What should we do if we get a hw irq event on an illegal vector?
+ * Each architecture has to answer this themself.
*/
-static void end_none(unsigned int irq) { }
-static void enable_none(unsigned int irq) { }
-static void disable_none(unsigned int irq) { }
-static void shutdown_none(unsigned int irq) { }
-static unsigned int startup_none(unsigned int irq) { return 0; }
-
-static void ack_none(unsigned int irq)
+static void ack_bad(unsigned int irq)
{
- /*
- * 'what should we do if we get a hw irq event on an illegal vector'.
- * each architecture has to answer this themself.
- */
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ print_irq_desc(irq, desc);
ack_bad_irq(irq);
}
-struct hw_interrupt_type no_irq_type = {
- .typename = "none",
- .startup = startup_none,
- .shutdown = shutdown_none,
- .enable = enable_none,
- .disable = disable_none,
- .ack = ack_none,
- .end = end_none,
- .set_affinity = NULL
+/*
+ * NOP functions
+ */
+static void noop(unsigned int irq)
+{
+}
+
+static unsigned int noop_ret(unsigned int irq)
+{
+ return 0;
+}
+
+/*
+ * Generic no controller implementation
+ */
+struct irq_chip no_irq_chip = {
+ .name = "none",
+ .startup = noop_ret,
+ .shutdown = noop,
+ .enable = noop,
+ .disable = noop,
+ .ack = ack_bad,
+ .end = noop,
+};
+
+/*
+ * Generic dummy implementation which can be used for
+ * real dumb interrupt sources
+ */
+struct irq_chip dummy_irq_chip = {
+ .name = "dummy",
+ .startup = noop_ret,
+ .shutdown = noop,
+ .enable = noop,
+ .disable = noop,
+ .ack = noop,
+ .mask = noop,
+ .unmask = noop,
+ .end = noop,
};
/*
* Special, empty irq handler:
*/
-irqreturn_t no_action(int cpl, void *dev_id, struct pt_regs *regs)
+irqreturn_t no_action(int cpl, void *dev_id)
{
return IRQ_NONE;
}
-/*
- * Have got an event to handle:
+/**
+ * handle_IRQ_event - irq action chain handler
+ * @irq: the interrupt number
+ * @action: the interrupt action chain for this irq
+ *
+ * Handles the action chain of an irq event
*/
-fastcall irqreturn_t handle_IRQ_event(unsigned int irq, struct pt_regs *regs,
- struct irqaction *action)
+irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
{
irqreturn_t ret, retval = IRQ_NONE;
unsigned int status = 0;
- if (!(action->flags & SA_INTERRUPT))
- local_irq_enable();
+ if (!(action->flags & IRQF_DISABLED))
+ local_irq_enable_in_hardirq();
do {
- ret = action->handler(irq, action->dev_id, regs);
+ ret = action->handler(irq, action->dev_id);
if (ret == IRQ_HANDLED)
status |= action->flags;
retval |= ret;
action = action->next;
} while (action);
- if (status & SA_SAMPLE_RANDOM)
+ if (status & IRQF_SAMPLE_RANDOM)
add_interrupt_randomness(irq);
local_irq_disable();
return retval;
}
-/*
- * do_IRQ handles all normal device IRQ's (the special
+#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
+/**
+ * __do_IRQ - original all in one highlevel IRQ handler
+ * @irq: the interrupt number
+ *
+ * __do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
+ *
+ * This is the original x86 implementation which is used for every
+ * interrupt type.
*/
-fastcall unsigned int __do_IRQ(unsigned int irq, struct pt_regs *regs)
+unsigned int __do_IRQ(unsigned int irq)
{
- irq_desc_t *desc = irq_desc + irq;
- struct irqaction * action;
+ struct irq_desc *desc = irq_to_desc(irq);
+ struct irqaction *action;
unsigned int status;
- kstat_this_cpu.irqs[irq]++;
+ kstat_incr_irqs_this_cpu(irq, desc);
+
if (CHECK_IRQ_PER_CPU(desc->status)) {
irqreturn_t action_ret;
/*
* No locking required for CPU-local interrupts:
*/
- if (desc->chip->ack)
+ if (desc->chip->ack) {
desc->chip->ack(irq);
- action_ret = handle_IRQ_event(irq, regs, desc->action);
+ /* get new one */
+ desc = irq_remap_to_desc(irq, desc);
+ }
+ if (likely(!(desc->status & IRQ_DISABLED))) {
+ action_ret = handle_IRQ_event(irq, desc->action);
+ if (!noirqdebug)
+ note_interrupt(irq, desc, action_ret);
+ }
desc->chip->end(irq);
return 1;
}
spin_lock(&desc->lock);
- if (desc->chip->ack)
+ if (desc->chip->ack) {
desc->chip->ack(irq);
+ desc = irq_remap_to_desc(irq, desc);
+ }
/*
* REPLAY is when Linux resends an IRQ that was dropped earlier
* WAITING is used by probe to mark irqs that are being tested
spin_unlock(&desc->lock);
- action_ret = handle_IRQ_event(irq, regs, action);
+ action_ret = handle_IRQ_event(irq, action);
+ if (!noirqdebug)
+ note_interrupt(irq, desc, action_ret);
spin_lock(&desc->lock);
- if (!noirqdebug)
- note_interrupt(irq, desc, action_ret, regs);
if (likely(!(desc->status & IRQ_PENDING)))
break;
desc->status &= ~IRQ_PENDING;
return 1;
}
+#endif
+
+void early_init_irq_lock_class(void)
+{
+ struct irq_desc *desc;
+ int i;
+
+ for_each_irq_desc(i, desc) {
+ lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+ }
+}
+
+#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);
Code Review / linux-2.6.git / blobdiff