lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

genirq: Add IRQ affinity notifiers

Browse Source 
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>
This commit is contained in:
Ben Hutchings
2011-01-19 21:01:44 +00:00
committed by Thomas Gleixner
parent 1bae4ce27c
commit cd7eab44e9
3 changed files with 117 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
include/linux/interrupt.h
View File

@ -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;
}