linux/kernel/irq/numa_migrate.c

133 lines
2.9 KiB
C

/*
* NUMA irq-desc migration code
*
* Migrate IRQ data structures (irq_desc, chip_data, etc.) over to
* the new "home node" of the IRQ.
*/
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include "internals.h"
static void init_copy_kstat_irqs(struct irq_desc *old_desc,
struct irq_desc *desc,
int cpu, int nr)
{
init_kstat_irqs(desc, cpu, nr);
if (desc->kstat_irqs != old_desc->kstat_irqs)
memcpy(desc->kstat_irqs, old_desc->kstat_irqs,
nr * sizeof(*desc->kstat_irqs));
}
static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
{
if (old_desc->kstat_irqs == desc->kstat_irqs)
return;
kfree(old_desc->kstat_irqs);
old_desc->kstat_irqs = NULL;
}
static bool init_copy_one_irq_desc(int irq, struct irq_desc *old_desc,
struct irq_desc *desc, int cpu)
{
memcpy(desc, old_desc, sizeof(struct irq_desc));
if (!init_alloc_desc_masks(desc, cpu, false)) {
printk(KERN_ERR "irq %d: can not get new irq_desc cpumask "
"for migration.\n", irq);
return false;
}
spin_lock_init(&desc->lock);
desc->cpu = cpu;
lockdep_set_class(&desc->lock, &irq_desc_lock_class);
init_copy_kstat_irqs(old_desc, desc, cpu, nr_cpu_ids);
init_copy_desc_masks(old_desc, desc);
arch_init_copy_chip_data(old_desc, desc, cpu);
return true;
}
static void free_one_irq_desc(struct irq_desc *old_desc, struct irq_desc *desc)
{
free_kstat_irqs(old_desc, desc);
arch_free_chip_data(old_desc, desc);
}
static struct irq_desc *__real_move_irq_desc(struct irq_desc *old_desc,
int cpu)
{
struct irq_desc *desc;
unsigned int irq;
unsigned long flags;
int node;
irq = old_desc->irq;
spin_lock_irqsave(&sparse_irq_lock, flags);
/* We have to check it to avoid races with another CPU */
desc = irq_desc_ptrs[irq];
if (desc && old_desc != desc)
goto out_unlock;
node = cpu_to_node(cpu);
desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
if (!desc) {
printk(KERN_ERR "irq %d: can not get new irq_desc "
"for migration.\n", irq);
/* still use old one */
desc = old_desc;
goto out_unlock;
}
if (!init_copy_one_irq_desc(irq, old_desc, desc, cpu)) {
/* still use old one */
kfree(desc);
desc = old_desc;
goto out_unlock;
}
irq_desc_ptrs[irq] = desc;
spin_unlock_irqrestore(&sparse_irq_lock, flags);
/* free the old one */
free_one_irq_desc(old_desc, desc);
spin_unlock(&old_desc->lock);
kfree(old_desc);
spin_lock(&desc->lock);
return desc;
out_unlock:
spin_unlock_irqrestore(&sparse_irq_lock, flags);
return desc;
}
struct irq_desc *move_irq_desc(struct irq_desc *desc, int cpu)
{
int old_cpu;
int node, old_node;
/* those all static, do move them */
if (desc->irq < NR_IRQS_LEGACY)
return desc;
old_cpu = desc->cpu;
if (old_cpu != cpu) {
node = cpu_to_node(cpu);
old_node = cpu_to_node(old_cpu);
if (old_node != node)
desc = __real_move_irq_desc(desc, cpu);
else
desc->cpu = cpu;
}
return desc;
}