genirq: Introduce IRQD_AFFINITY_MANAGED flag

Interupts marked with this flag are excluded from user space interrupt
affinity changes. Contrary to the IRQ_NO_BALANCING flag, the kernel internal
affinity mechanism is not blocked.

This flag will be used for multi-queue device interrupts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: linux-block@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: linux-nvme@lists.infradead.org
Cc: axboe@fb.com
Cc: agordeev@redhat.com
Link: http://lkml.kernel.org/r/1467621574-8277-3-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Thomas Gleixner 2016-07-04 17:39:23 +09:00
parent b6140914fd
commit 9c2555835b
4 changed files with 28 additions and 4 deletions

View File

@ -197,6 +197,7 @@ struct irq_data {
* IRQD_IRQ_INPROGRESS - In progress state of the interrupt
* IRQD_WAKEUP_ARMED - Wakeup mode armed
* IRQD_FORWARDED_TO_VCPU - The interrupt is forwarded to a VCPU
* IRQD_AFFINITY_MANAGED - Affinity is auto-managed by the kernel
*/
enum {
IRQD_TRIGGER_MASK = 0xf,
@ -212,6 +213,7 @@ enum {
IRQD_IRQ_INPROGRESS = (1 << 18),
IRQD_WAKEUP_ARMED = (1 << 19),
IRQD_FORWARDED_TO_VCPU = (1 << 20),
IRQD_AFFINITY_MANAGED = (1 << 21),
};
#define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
@ -305,6 +307,11 @@ static inline void irqd_clr_forwarded_to_vcpu(struct irq_data *d)
__irqd_to_state(d) &= ~IRQD_FORWARDED_TO_VCPU;
}
static inline bool irqd_affinity_is_managed(struct irq_data *d)
{
return __irqd_to_state(d) & IRQD_AFFINITY_MANAGED;
}
#undef __irqd_to_state
static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d)

View File

@ -105,6 +105,8 @@ static inline void unregister_handler_proc(unsigned int irq,
struct irqaction *action) { }
#endif
extern bool irq_can_set_affinity_usr(unsigned int irq);
extern int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask);
extern void irq_set_thread_affinity(struct irq_desc *desc);

View File

@ -115,12 +115,12 @@ EXPORT_SYMBOL(synchronize_irq);
#ifdef CONFIG_SMP
cpumask_var_t irq_default_affinity;
static int __irq_can_set_affinity(struct irq_desc *desc)
static bool __irq_can_set_affinity(struct irq_desc *desc)
{
if (!desc || !irqd_can_balance(&desc->irq_data) ||
!desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
return 0;
return 1;
return false;
return true;
}
/**
@ -133,6 +133,21 @@ int irq_can_set_affinity(unsigned int irq)
return __irq_can_set_affinity(irq_to_desc(irq));
}
/**
* irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
* @irq: Interrupt to check
*
* Like irq_can_set_affinity() above, but additionally checks for the
* AFFINITY_MANAGED flag.
*/
bool irq_can_set_affinity_usr(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
return __irq_can_set_affinity(desc) &&
!irqd_affinity_is_managed(&desc->irq_data);
}
/**
* irq_set_thread_affinity - Notify irq threads to adjust affinity
* @desc: irq descriptor which has affitnity changed

View File

@ -96,7 +96,7 @@ static ssize_t write_irq_affinity(int type, struct file *file,
cpumask_var_t new_value;
int err;
if (!irq_can_set_affinity(irq) || no_irq_affinity)
if (!irq_can_set_affinity_usr(irq) || no_irq_affinity)
return -EIO;
if (!alloc_cpumask_var(&new_value, GFP_KERNEL))