summaryrefslogtreecommitdiff
path: root/include/linux
diff options
context:
space:
mode:
authorBen Hutchings <bhutchings@solarflare.com>2011-01-19 21:01:44 +0000
committerThomas Gleixner <tglx@linutronix.de>2011-01-22 17:34:25 +0100
commitcd7eab44e9946c28d595abe3e9a43e945bc49141 (patch)
treeb8b0c1beebbcad7785422a463504a374bb43cdea /include/linux
parent1bae4ce27c9c90344f23c65ea6966c50ffeae2f5 (diff)
genirq: Add IRQ affinity notifiers
When initiating I/O on a multiqueue and multi-IRQ device, we may want to select a queue for which the response will be handled on the same or a nearby CPU. This requires a reverse-map of IRQ affinity. Add a notification mechanism to support this. This is based closely on work by Thomas Gleixner <tglx@linutronix.de>. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Cc: linux-net-drivers@solarflare.com Cc: Tom Herbert <therbert@google.com> Cc: David Miller <davem@davemloft.net> LKML-Reference: <1295470904.11126.84.camel@bwh-desktop> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/interrupt.h33
-rw-r--r--include/linux/irqdesc.h3
2 files changed, 35 insertions, 1 deletions
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 55e0d4253e49..63c5ad78e37c 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -14,6 +14,8 @@
#include <linux/smp.h>
#include <linux/percpu.h>
#include <linux/hrtimer.h>
+#include <linux/kref.h>
+#include <linux/workqueue.h>
#include <asm/atomic.h>
#include <asm/ptrace.h>
@@ -240,6 +242,35 @@ extern int irq_can_set_affinity(unsigned int irq);
extern int irq_select_affinity(unsigned int irq);
extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
+
+/**
+ * struct irq_affinity_notify - context for notification of IRQ affinity changes
+ * @irq: Interrupt to which notification applies
+ * @kref: Reference count, for internal use
+ * @work: Work item, for internal use
+ * @notify: Function to be called on change. This will be
+ * called in process context.
+ * @release: Function to be called on release. This will be
+ * called in process context. Once registered, the
+ * structure must only be freed when this function is
+ * called or later.
+ */
+struct irq_affinity_notify {
+ unsigned int irq;
+ struct kref kref;
+ struct work_struct work;
+ void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
+ void (*release)(struct kref *ref);
+};
+
+extern int
+irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
+
+static inline void irq_run_affinity_notifiers(void)
+{
+ flush_scheduled_work();
+}
+
#else /* CONFIG_SMP */
static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
@@ -255,7 +286,7 @@ static inline int irq_can_set_affinity(unsigned int irq)
static inline int irq_select_affinity(unsigned int irq) { return 0; }
static inline int irq_set_affinity_hint(unsigned int irq,
- const struct cpumask *m)
+ const struct cpumask *m)
{
return -EINVAL;
}
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index c1a95b7b58de..bfef56dadddb 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -8,6 +8,7 @@
* For now it's included from <linux/irq.h>
*/
+struct irq_affinity_notify;
struct proc_dir_entry;
struct timer_rand_state;
/**
@@ -24,6 +25,7 @@ struct timer_rand_state;
* @last_unhandled: aging timer for unhandled count
* @irqs_unhandled: stats field for spurious unhandled interrupts
* @lock: locking for SMP
+ * @affinity_notify: context for notification of affinity changes
* @pending_mask: pending rebalanced interrupts
* @threads_active: number of irqaction threads currently running
* @wait_for_threads: wait queue for sync_irq to wait for threaded handlers
@@ -70,6 +72,7 @@ struct irq_desc {
raw_spinlock_t lock;
#ifdef CONFIG_SMP
const struct cpumask *affinity_hint;
+ struct irq_affinity_notify *affinity_notify;
#ifdef CONFIG_GENERIC_PENDING_IRQ
cpumask_var_t pending_mask;
#endif