Commit 48b15a79 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

irqdomain: Cache irq_data instead of a virq number in the revmap 



Caching a virq number in the revmap is pretty inefficient, as
it means we will need to convert it back to either an irq_data
or irq_desc to do anything with it.

It is also a bit odd, as the radix tree does cache irq_data
pointers.

Change the revmap type to be an irq_data pointer instead of
an unsigned int, and preserve the current API for now.

Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent 426fa316

include/linux/irqdomain.h

+2 −2
Original line number Diff line number Diff line
@@ -151,7 +151,7 @@ struct irq_domain_chip_generic; 
 * Revmap data, used internally by irq_domain

 * @revmap_size: Size of the linear map table @revmap[]

 * @revmap_tree: Radix map tree for hwirqs that don't fit in the linear map

 * @revmap: Linear table of hwirq->virq reverse mappings

 * @revmap: Linear table of irq_data pointers

 */

struct irq_domain {

	struct list_head link;
@@ -174,7 +174,7 @@ struct irq_domain { 
	unsigned int revmap_size;

	struct radix_tree_root revmap_tree;

	struct mutex revmap_tree_mutex;

	unsigned int revmap[];

	struct irq_data *revmap[];

};



/* Irq domain flags */

kernel/irq/irqdomain.c

+11 −5
Original line number Diff line number Diff line
@@ -505,7 +505,7 @@ static void irq_domain_clear_mapping(struct irq_domain *domain, 
		return;



	if (hwirq < domain->revmap_size) {

		domain->revmap[hwirq] = 0;

		domain->revmap[hwirq] = NULL;

	} else {

		mutex_lock(&domain->revmap_tree_mutex);

		radix_tree_delete(&domain->revmap_tree, hwirq);
@@ -521,7 +521,7 @@ static void irq_domain_set_mapping(struct irq_domain *domain, 
		return;



	if (hwirq < domain->revmap_size) {

		domain->revmap[hwirq] = irq_data->irq;

		domain->revmap[hwirq] = irq_data;

	} else {

		mutex_lock(&domain->revmap_tree_mutex);

		radix_tree_insert(&domain->revmap_tree, hwirq, irq_data);
@@ -913,7 +913,7 @@ unsigned int irq_find_mapping(struct irq_domain *domain, 


	/* Check if the hwirq is in the linear revmap. */

	if (hwirq < domain->revmap_size)

		return domain->revmap[hwirq];

		return domain->revmap[hwirq]->irq;



	rcu_read_lock();

	data = radix_tree_lookup(&domain->revmap_tree, hwirq);
@@ -1496,8 +1496,14 @@ static void irq_domain_fix_revmap(struct irq_data *d) 
{

	void __rcu **slot;



	if (irq_domain_is_nomap(d->domain) || d->hwirq < d->domain->revmap_size)

		return; /* Not using radix tree. */

	if (irq_domain_is_nomap(d->domain))

		return;



	if (d->hwirq < d->domain->revmap_size) {

		/* Not using radix tree */

		d->domain->revmap[d->hwirq] = d;

		return;

	}



	/* Fix up the revmap. */

	mutex_lock(&d->domain->revmap_tree_mutex);