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Diffstat (limited to 'kernel/irq')
-rw-r--r--kernel/irq/irqdomain.c65
1 files changed, 25 insertions, 40 deletions
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index c0e638ba9c2a..170724a07a2c 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -686,16 +686,11 @@ EXPORT_SYMBOL_GPL(irq_dispose_mapping);
* irq_find_mapping() - Find a linux irq from an hw irq number.
* @domain: domain owning this hardware interrupt
* @hwirq: hardware irq number in that domain space
- *
- * This is a slow path, for use by generic code. It's expected that an
- * irq controller implementation directly calls the appropriate low level
- * mapping function.
*/
unsigned int irq_find_mapping(struct irq_domain *domain,
irq_hw_number_t hwirq)
{
- unsigned int i;
- unsigned int hint = hwirq % nr_irqs;
+ struct irq_data *data;
/* Look for default domain if nececssary */
if (domain == NULL)
@@ -703,22 +698,25 @@ unsigned int irq_find_mapping(struct irq_domain *domain,
if (domain == NULL)
return 0;
- /* legacy -> bail early */
- if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
+ switch (domain->revmap_type) {
+ case IRQ_DOMAIN_MAP_LEGACY:
return irq_domain_legacy_revmap(domain, hwirq);
-
- /* Slow path does a linear search of the map */
- if (hint == 0)
- hint = 1;
- i = hint;
- do {
- struct irq_data *data = irq_get_irq_data(i);
+ case IRQ_DOMAIN_MAP_LINEAR:
+ return irq_linear_revmap(domain, hwirq);
+ case IRQ_DOMAIN_MAP_TREE:
+ rcu_read_lock();
+ data = radix_tree_lookup(&domain->revmap_data.tree, hwirq);
+ rcu_read_unlock();
+ if (data)
+ return data->irq;
+ break;
+ case IRQ_DOMAIN_MAP_NOMAP:
+ data = irq_get_irq_data(hwirq);
if (data && (data->domain == domain) && (data->hwirq == hwirq))
- return i;
- i++;
- if (i >= nr_irqs)
- i = 1;
- } while(i != hint);
+ return hwirq;
+ break;
+ }
+
return 0;
}
EXPORT_SYMBOL_GPL(irq_find_mapping);
@@ -728,32 +726,19 @@ EXPORT_SYMBOL_GPL(irq_find_mapping);
* @domain: domain owning this hardware interrupt
* @hwirq: hardware irq number in that domain space
*
- * This is a fast path, for use by irq controller code that uses linear
- * revmaps. It does fallback to the slow path if the revmap doesn't exist
- * yet and will create the revmap entry with appropriate locking
+ * This is a fast path that can be called directly by irq controller code to
+ * save a handful of instructions.
*/
unsigned int irq_linear_revmap(struct irq_domain *domain,
irq_hw_number_t hwirq)
{
- unsigned int *revmap;
+ BUG_ON(domain->revmap_type != IRQ_DOMAIN_MAP_LINEAR);
- if (WARN_ON_ONCE(domain->revmap_type != IRQ_DOMAIN_MAP_LINEAR))
- return irq_find_mapping(domain, hwirq);
-
- /* Check revmap bounds */
- if (unlikely(hwirq >= domain->revmap_data.linear.size))
- return irq_find_mapping(domain, hwirq);
-
- /* Check if revmap was allocated */
- revmap = domain->revmap_data.linear.revmap;
- if (unlikely(revmap == NULL))
- return irq_find_mapping(domain, hwirq);
-
- /* Fill up revmap with slow path if no mapping found */
- if (unlikely(!revmap[hwirq]))
- revmap[hwirq] = irq_find_mapping(domain, hwirq);
+ /* Check revmap bounds; complain if exceeded */
+ if (WARN_ON(hwirq >= domain->revmap_data.linear.size))
+ return 0;
- return revmap[hwirq];
+ return domain->revmap_data.linear.revmap[hwirq];
}
EXPORT_SYMBOL_GPL(irq_linear_revmap);