diff options
Diffstat (limited to 'lib/cpu_rmap.c')
| -rw-r--r-- | lib/cpu_rmap.c | 62 |
1 files changed, 50 insertions, 12 deletions
diff --git a/lib/cpu_rmap.c b/lib/cpu_rmap.c index 987acfafeb83..4f134d8907a7 100644 --- a/lib/cpu_rmap.c +++ b/lib/cpu_rmap.c @@ -8,10 +8,8 @@ */ #include <linux/cpu_rmap.h> -#ifdef CONFIG_GENERIC_HARDIRQS #include <linux/interrupt.h> -#endif -#include <linux/module.h> +#include <linux/export.h> /* * These functions maintain a mapping from CPUs to some ordered set of @@ -45,6 +43,7 @@ struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags) if (!rmap) return NULL; + kref_init(&rmap->refcount); rmap->obj = (void **)((char *)rmap + obj_offset); /* Initially assign CPUs to objects on a rota, since we have @@ -63,6 +62,35 @@ struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags) } EXPORT_SYMBOL(alloc_cpu_rmap); +/** + * cpu_rmap_release - internal reclaiming helper called from kref_put + * @ref: kref to struct cpu_rmap + */ +static void cpu_rmap_release(struct kref *ref) +{ + struct cpu_rmap *rmap = container_of(ref, struct cpu_rmap, refcount); + kfree(rmap); +} + +/** + * cpu_rmap_get - internal helper to get new ref on a cpu_rmap + * @rmap: reverse-map allocated with alloc_cpu_rmap() + */ +static inline void cpu_rmap_get(struct cpu_rmap *rmap) +{ + kref_get(&rmap->refcount); +} + +/** + * cpu_rmap_put - release ref on a cpu_rmap + * @rmap: reverse-map allocated with alloc_cpu_rmap() + */ +int cpu_rmap_put(struct cpu_rmap *rmap) +{ + return kref_put(&rmap->refcount, cpu_rmap_release); +} +EXPORT_SYMBOL(cpu_rmap_put); + /* Reevaluate nearest object for given CPU, comparing with the given * neighbours at the given distance. */ @@ -183,8 +211,6 @@ int cpu_rmap_update(struct cpu_rmap *rmap, u16 index, } EXPORT_SYMBOL(cpu_rmap_update); -#ifdef CONFIG_GENERIC_HARDIRQS - /* Glue between IRQ affinity notifiers and CPU rmaps */ struct irq_glue { @@ -197,8 +223,7 @@ struct irq_glue { * free_irq_cpu_rmap - free a CPU affinity reverse-map used for IRQs * @rmap: Reverse-map allocated with alloc_irq_cpu_map(), or %NULL * - * Must be called in process context, before freeing the IRQs, and - * without holding any locks required by global workqueue items. + * Must be called in process context, before freeing the IRQs. */ void free_irq_cpu_rmap(struct cpu_rmap *rmap) { @@ -212,12 +237,18 @@ void free_irq_cpu_rmap(struct cpu_rmap *rmap) glue = rmap->obj[index]; irq_set_affinity_notifier(glue->notify.irq, NULL); } - irq_run_affinity_notifiers(); - kfree(rmap); + cpu_rmap_put(rmap); } EXPORT_SYMBOL(free_irq_cpu_rmap); +/** + * irq_cpu_rmap_notify - callback for IRQ subsystem when IRQ affinity updated + * @notify: struct irq_affinity_notify passed by irq/manage.c + * @mask: cpu mask for new SMP affinity + * + * This is executed in workqueue context. + */ static void irq_cpu_rmap_notify(struct irq_affinity_notify *notify, const cpumask_t *mask) { @@ -230,10 +261,16 @@ irq_cpu_rmap_notify(struct irq_affinity_notify *notify, const cpumask_t *mask) pr_warning("irq_cpu_rmap_notify: update failed: %d\n", rc); } +/** + * irq_cpu_rmap_release - reclaiming callback for IRQ subsystem + * @ref: kref to struct irq_affinity_notify passed by irq/manage.c + */ static void irq_cpu_rmap_release(struct kref *ref) { struct irq_glue *glue = container_of(ref, struct irq_glue, notify.kref); + + cpu_rmap_put(glue->rmap); kfree(glue); } @@ -258,12 +295,13 @@ int irq_cpu_rmap_add(struct cpu_rmap *rmap, int irq) glue->notify.notify = irq_cpu_rmap_notify; glue->notify.release = irq_cpu_rmap_release; glue->rmap = rmap; + cpu_rmap_get(rmap); glue->index = cpu_rmap_add(rmap, glue); rc = irq_set_affinity_notifier(irq, &glue->notify); - if (rc) + if (rc) { + cpu_rmap_put(glue->rmap); kfree(glue); + } return rc; } EXPORT_SYMBOL(irq_cpu_rmap_add); - -#endif /* CONFIG_GENERIC_HARDIRQS */ |