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Diffstat (limited to 'arch/arm/kernel/irq.c')
-rw-r--r--arch/arm/kernel/irq.c129
1 files changed, 126 insertions, 3 deletions
diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c
index 5b35e76c3ce4..5e0656e88918 100644
--- a/arch/arm/kernel/irq.c
+++ b/arch/arm/kernel/irq.c
@@ -32,6 +32,7 @@
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/kallsyms.h>
+#include <linux/proc_fs.h>
#include <asm/irq.h>
#include <asm/system.h>
@@ -85,6 +86,23 @@ static struct irqdesc bad_irq_desc = {
.disable_depth = 1,
};
+#ifdef CONFIG_SMP
+void synchronize_irq(unsigned int irq)
+{
+ struct irqdesc *desc = irq_desc + irq;
+
+ while (desc->running)
+ barrier();
+}
+EXPORT_SYMBOL(synchronize_irq);
+
+#define smp_set_running(desc) do { desc->running = 1; } while (0)
+#define smp_clear_running(desc) do { desc->running = 0; } while (0)
+#else
+#define smp_set_running(desc) do { } while (0)
+#define smp_clear_running(desc) do { } while (0)
+#endif
+
/**
* disable_irq_nosync - disable an irq without waiting
* @irq: Interrupt to disable
@@ -232,6 +250,9 @@ unlock:
#ifdef CONFIG_ARCH_ACORN
show_fiq_list(p, v);
#endif
+#ifdef CONFIG_SMP
+ show_ipi_list(p);
+#endif
seq_printf(p, "Err: %10lu\n", irq_err_count);
}
return 0;
@@ -329,18 +350,22 @@ void
do_simple_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
{
struct irqaction *action;
- const int cpu = smp_processor_id();
+ const unsigned int cpu = smp_processor_id();
desc->triggered = 1;
kstat_cpu(cpu).irqs[irq]++;
+ smp_set_running(desc);
+
action = desc->action;
if (action) {
int ret = __do_irq(irq, action, regs);
if (ret != IRQ_HANDLED)
report_bad_irq(irq, regs, desc, ret);
}
+
+ smp_clear_running(desc);
}
/*
@@ -350,7 +375,7 @@ do_simple_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
void
do_edge_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
{
- const int cpu = smp_processor_id();
+ const unsigned int cpu = smp_processor_id();
desc->triggered = 1;
@@ -414,7 +439,7 @@ void
do_level_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
{
struct irqaction *action;
- const int cpu = smp_processor_id();
+ const unsigned int cpu = smp_processor_id();
desc->triggered = 1;
@@ -426,6 +451,8 @@ do_level_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
if (likely(!desc->disable_depth)) {
kstat_cpu(cpu).irqs[irq]++;
+ smp_set_running(desc);
+
/*
* Return with this interrupt masked if no action
*/
@@ -440,6 +467,8 @@ do_level_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
!check_irq_lock(desc, irq, regs)))
desc->chip->unmask(irq);
}
+
+ smp_clear_running(desc);
}
}
@@ -878,8 +907,97 @@ out:
EXPORT_SYMBOL(probe_irq_off);
+#ifdef CONFIG_SMP
+static void route_irq(struct irqdesc *desc, unsigned int irq, unsigned int cpu)
+{
+ pr_debug("IRQ%u: moving from cpu%u to cpu%u\n", irq, desc->cpu, cpu);
+
+ spin_lock_irq(&irq_controller_lock);
+ desc->cpu = cpu;
+ desc->chip->set_cpu(desc, irq, cpu);
+ spin_unlock_irq(&irq_controller_lock);
+}
+
+#ifdef CONFIG_PROC_FS
+static int
+irq_affinity_read_proc(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
+{
+ struct irqdesc *desc = irq_desc + ((int)data);
+ int len = cpumask_scnprintf(page, count, desc->affinity);
+
+ if (count - len < 2)
+ return -EINVAL;
+ page[len++] = '\n';
+ page[len] = '\0';
+
+ return len;
+}
+
+static int
+irq_affinity_write_proc(struct file *file, const char __user *buffer,
+ unsigned long count, void *data)
+{
+ unsigned int irq = (unsigned int)data;
+ struct irqdesc *desc = irq_desc + irq;
+ cpumask_t affinity, tmp;
+ int ret = -EIO;
+
+ if (!desc->chip->set_cpu)
+ goto out;
+
+ ret = cpumask_parse(buffer, count, affinity);
+ if (ret)
+ goto out;
+
+ cpus_and(tmp, affinity, cpu_online_map);
+ if (cpus_empty(tmp)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ desc->affinity = affinity;
+ route_irq(desc, irq, first_cpu(tmp));
+ ret = count;
+
+ out:
+ return ret;
+}
+#endif
+#endif
+
void __init init_irq_proc(void)
{
+#if defined(CONFIG_SMP) && defined(CONFIG_PROC_FS)
+ struct proc_dir_entry *dir;
+ int irq;
+
+ dir = proc_mkdir("irq", 0);
+ if (!dir)
+ return;
+
+ for (irq = 0; irq < NR_IRQS; irq++) {
+ struct proc_dir_entry *entry;
+ struct irqdesc *desc;
+ char name[16];
+
+ desc = irq_desc + irq;
+ memset(name, 0, sizeof(name));
+ snprintf(name, sizeof(name) - 1, "%u", irq);
+
+ desc->procdir = proc_mkdir(name, dir);
+ if (!desc->procdir)
+ continue;
+
+ entry = create_proc_entry("smp_affinity", 0600, desc->procdir);
+ if (entry) {
+ entry->nlink = 1;
+ entry->data = (void *)irq;
+ entry->read_proc = irq_affinity_read_proc;
+ entry->write_proc = irq_affinity_write_proc;
+ }
+ }
+#endif
}
void __init init_IRQ(void)
@@ -888,6 +1006,11 @@ void __init init_IRQ(void)
extern void init_dma(void);
int irq;
+#ifdef CONFIG_SMP
+ bad_irq_desc.affinity = CPU_MASK_ALL;
+ bad_irq_desc.cpu = smp_processor_id();
+#endif
+
for (irq = 0, desc = irq_desc; irq < NR_IRQS; irq++, desc++) {
*desc = bad_irq_desc;
INIT_LIST_HEAD(&desc->pend);