[PATCH] Add a function to handle interrupt affinity setting

Provide funtions to:
 - check, whether an interrupt can set the affinity
 - pin the interrupt to a given cpu

Necessary for the ability to setup clocksources more flexible (e.g.  use the
different HPET channels per CPU)

[akpm@osdl.org: alpha build fix]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Thomas Gleixner 2007-02-16 01:27:25 -08:00 committed by Linus Torvalds
parent 950f4427c2
commit 771ee3b04e
3 changed files with 51 additions and 21 deletions

View File

@ -238,11 +238,21 @@ static inline void set_pending_irq(unsigned int irq, cpumask_t mask)
#endif /* CONFIG_GENERIC_PENDING_IRQ */
extern int irq_set_affinity(unsigned int irq, cpumask_t cpumask);
extern int irq_can_set_affinity(unsigned int irq);
#else /* CONFIG_SMP */
#define move_native_irq(x)
#define move_masked_irq(x)
static inline int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
{
return -EINVAL;
}
static inline int irq_can_set_affinity(unsigned int irq) { return 0; }
#endif /* CONFIG_SMP */
#ifdef CONFIG_IRQBALANCE

View File

@ -38,6 +38,46 @@ void synchronize_irq(unsigned int irq)
}
EXPORT_SYMBOL(synchronize_irq);
/**
* irq_can_set_affinity - Check if the affinity of a given irq can be set
* @irq: Interrupt to check
*
*/
int irq_can_set_affinity(unsigned int irq)
{
struct irq_desc *desc = irq_desc + irq;
if (CHECK_IRQ_PER_CPU(desc->status) || !desc->chip ||
!desc->chip->set_affinity)
return 0;
return 1;
}
/**
* irq_set_affinity - Set the irq affinity of a given irq
* @irq: Interrupt to set affinity
* @cpumask: cpumask
*
*/
int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
{
struct irq_desc *desc = irq_desc + irq;
if (!desc->chip->set_affinity)
return -EINVAL;
set_balance_irq_affinity(irq, cpumask);
#ifdef CONFIG_GENERIC_PENDING_IRQ
set_pending_irq(irq, cpumask);
#else
desc->affinity = cpumask;
desc->chip->set_affinity(irq, cpumask);
#endif
return 0;
}
#endif
/**

View File

@ -16,26 +16,6 @@ static struct proc_dir_entry *root_irq_dir;
#ifdef CONFIG_SMP
#ifdef CONFIG_GENERIC_PENDING_IRQ
void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val)
{
set_balance_irq_affinity(irq, mask_val);
/*
* Save these away for later use. Re-progam when the
* interrupt is pending
*/
set_pending_irq(irq, mask_val);
}
#else
void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val)
{
set_balance_irq_affinity(irq, mask_val);
irq_desc[irq].affinity = mask_val;
irq_desc[irq].chip->set_affinity(irq, mask_val);
}
#endif
static int irq_affinity_read_proc(char *page, char **start, off_t off,
int count, int *eof, void *data)
{
@ -73,7 +53,7 @@ static int irq_affinity_write_proc(struct file *file, const char __user *buffer,
code to set default SMP affinity. */
return select_smp_affinity(irq) ? -EINVAL : full_count;
proc_set_irq_affinity(irq, new_value);
irq_set_affinity(irq, new_value);
return full_count;
}