static inline void free_masks(struct irq_desc *desc) { }
#endif
+void irq_lock_sparse(void)
+{
+ mutex_lock(&sparse_irq_lock);
+}
+
+void irq_unlock_sparse(void)
+{
+ mutex_unlock(&sparse_irq_lock);
+}
+
static struct irq_desc *alloc_desc(int irq, int node, struct module *owner)
{
struct irq_desc *desc;
unregister_irq_proc(irq, desc);
- mutex_lock(&sparse_irq_lock);
+ /*
+ * sparse_irq_lock protects also show_interrupts() and
+ * kstat_irq_usr(). Once we deleted the descriptor from the
+ * sparse tree we can free it. Access in proc will fail to
+ * lookup the descriptor.
+ */
delete_irq_desc(irq);
- mutex_unlock(&sparse_irq_lock);
free_masks(desc);
free_percpu(desc->kstat_irqs);
desc = alloc_desc(start + i, node, owner);
if (!desc)
goto err;
- mutex_lock(&sparse_irq_lock);
irq_insert_desc(start + i, desc);
- mutex_unlock(&sparse_irq_lock);
}
+ bitmap_set(allocated_irqs, start, cnt);
return start;
err:
for (i--; i >= 0; i--)
free_desc(start + i);
-
- mutex_lock(&sparse_irq_lock);
- bitmap_clear(allocated_irqs, start, cnt);
- mutex_unlock(&sparse_irq_lock);
return -ENOMEM;
}
desc->owner = owner;
}
+ bitmap_set(allocated_irqs, start, cnt);
return start;
}
if (from >= nr_irqs || (from + cnt) > nr_irqs)
return;
+ mutex_lock(&sparse_irq_lock);
for (i = 0; i < cnt; i++)
free_desc(from + i);
- mutex_lock(&sparse_irq_lock);
bitmap_clear(allocated_irqs, from, cnt);
mutex_unlock(&sparse_irq_lock);
}
from, cnt, 0);
ret = -EEXIST;
if (irq >=0 && start != irq)
- goto err;
+ goto unlock;
if (start + cnt > nr_irqs) {
ret = irq_expand_nr_irqs(start + cnt);
if (ret)
- goto err;
+ goto unlock;
}
-
- bitmap_set(allocated_irqs, start, cnt);
- mutex_unlock(&sparse_irq_lock);
- return alloc_descs(start, cnt, node, owner);
-
-err:
+ ret = alloc_descs(start, cnt, node, owner);
+unlock:
mutex_unlock(&sparse_irq_lock);
return ret;
}
raw_spin_unlock_irqrestore(&desc->lock, flags);
}
+/**
+ * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
+ * @irq: The interrupt number
+ * @cpu: The cpu number
+ *
+ * Returns the sum of interrupt counts on @cpu since boot for
+ * @irq. The caller must ensure that the interrupt is not removed
+ * concurrently.
+ */
unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
{
struct irq_desc *desc = irq_to_desc(irq);
*per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
}
+/**
+ * kstat_irqs - Get the statistics for an interrupt
+ * @irq: The interrupt number
+ *
+ * Returns the sum of interrupt counts on all cpus since boot for
+ * @irq. The caller must ensure that the interrupt is not removed
+ * concurrently.
+ */
unsigned int kstat_irqs(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
return sum;
}
+
+/**
+ * kstat_irqs_usr - Get the statistics for an interrupt
+ * @irq: The interrupt number
+ *
+ * Returns the sum of interrupt counts on all cpus since boot for
+ * @irq. Contrary to kstat_irqs() this can be called from any
+ * preemptible context. It's protected against concurrent removal of
+ * an interrupt descriptor when sparse irqs are enabled.
+ */
+unsigned int kstat_irqs_usr(unsigned int irq)
+{
+ int sum;
+
+ irq_lock_sparse();
+ sum = kstat_irqs(irq);
+ irq_unlock_sparse();
+ return sum;
+}