[PATCH 4/8] irqdomain: Simple NUMA awareness.

From: Paul Mundt
Date: Sat May 19 2012 - 02:12:36 EST


While common irqdesc allocation is node aware, the irqdomain code is not.

This plugs in NUMA node id proliferation across the various allocation
callsites by way of a new irq_domain_nid() helper. The irq_domain_nid()
routine takes an of_node pointer instead of an irq_domain as it's also
used for node placement of the irq domain data structure itself (at which
point only the of_node is known). For platforms that aren't DT capable,
we simply wrap in to numa_node_id() unconditionally.

In order for this to be generally supportable, it's also necessary to
make of_node_to_nid() generally available. This is accomplished by simply
bumping it down further in the header.

Presently we observe a number of regressions/inconsistencies on
NUMA-capable platforms:

- Platforms using irqdomains with legacy mappings, where the
irq_descs are allocated node-local and the irqdomain data
structure is not.

- Drivers implementing irqdomains will lose node locality
regardless of the underlying struct device's node id.

Signed-off-by: Paul Mundt <lethal@xxxxxxxxxxxx>
---
include/linux/of.h | 10 +++++-----
kernel/irq/irqdomain.c | 18 +++++++++++++-----
2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/include/linux/of.h b/include/linux/of.h
index fa7fb1d..6478859 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -158,11 +158,6 @@ static inline unsigned long of_read_ulong(const __be32 *cell, int size)

#define OF_BAD_ADDR ((u64)-1)

-#ifndef of_node_to_nid
-static inline int of_node_to_nid(struct device_node *np) { return -1; }
-#define of_node_to_nid of_node_to_nid
-#endif
-
extern struct device_node *of_find_node_by_name(struct device_node *from,
const char *name);
#define for_each_node_by_name(dn, name) \
@@ -351,6 +346,11 @@ static inline int of_machine_is_compatible(const char *compat)
#define of_match_node(_matches, _node) NULL
#endif /* CONFIG_OF */

+#ifndef of_node_to_nid
+static inline int of_node_to_nid(struct device_node *np) { return -1; }
+#define of_node_to_nid of_node_to_nid
+#endif
+
/**
* of_property_read_bool - Findfrom a property
* @np: device node from which the property value is to be read.
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 92e06442..5f0ca52 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -8,6 +8,7 @@
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_address.h>
+#include <linux/topology.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/smp.h>
@@ -25,6 +26,11 @@ static DEFINE_MUTEX(irq_domain_mutex);
static DEFINE_MUTEX(revmap_trees_mutex);
static struct irq_domain *irq_default_domain;

+static inline int irq_domain_nid(struct device_node *of_node)
+{
+ return of_node ? of_node_to_nid(of_node) : numa_node_id();
+}
+
/**
* irq_domain_alloc() - Allocate a new irq_domain data structure
* @of_node: optional device-tree node of the interrupt controller
@@ -43,7 +49,8 @@ static struct irq_domain *irq_domain_alloc(struct device_node *of_node,
{
struct irq_domain *domain;

- domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+ domain = kzalloc_node(sizeof(*domain), GFP_KERNEL,
+ irq_domain_nid(of_node));
if (WARN_ON(!domain))
return NULL;

@@ -226,7 +233,8 @@ struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
struct irq_domain *domain;
unsigned int *revmap;

- revmap = kzalloc(sizeof(*revmap) * size, GFP_KERNEL);
+ revmap = kzalloc_node(sizeof(*revmap) * size, GFP_KERNEL,
+ irq_domain_nid(of_node));
if (WARN_ON(!revmap))
return NULL;

@@ -364,7 +372,7 @@ unsigned int irq_create_direct_mapping(struct irq_domain *domain)
BUG_ON(domain == NULL);
WARN_ON(domain->revmap_type != IRQ_DOMAIN_MAP_NOMAP);

- virq = irq_alloc_desc_from(1, 0);
+ virq = irq_alloc_desc_from(1, irq_domain_nid(domain->of_node));
if (!virq) {
pr_debug("irq: create_direct virq allocation failed\n");
return 0;
@@ -430,9 +438,9 @@ unsigned int irq_create_mapping(struct irq_domain *domain,
hint = hwirq % nr_irqs;
if (hint == 0)
hint++;
- virq = irq_alloc_desc_from(hint, 0);
+ virq = irq_alloc_desc_from(hint, irq_domain_nid(domain->of_node));
if (virq <= 0)
- virq = irq_alloc_desc_from(1, 0);
+ virq = irq_alloc_desc_from(1, irq_domain_nid(domain->of_node));
if (virq <= 0) {
pr_debug("irq: -> virq allocation failed\n");
return 0;
--
1.7.9.rc0.28.g0e1cf

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