1#ifndef __LINUX_CPU_RMAP_H
2#define __LINUX_CPU_RMAP_H
3
4/*
5 * cpu_rmap.c: CPU affinity reverse-map support
6 * Copyright 2011 Solarflare Communications Inc.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published
10 * by the Free Software Foundation, incorporated herein by reference.
11 */
12
13#include <linux/cpumask.h>
14#include <linux/gfp.h>
15#include <linux/slab.h>
16#include <linux/kref.h>
17
18/**
19 * struct cpu_rmap - CPU affinity reverse-map
20 * @refcount: kref for object
21 * @size: Number of objects to be reverse-mapped
22 * @used: Number of objects added
23 * @obj: Pointer to array of object pointers
24 * @near: For each CPU, the index and distance to the nearest object,
25 * based on affinity masks
26 */
27struct cpu_rmap {
28 struct kref refcount;
29 u16 size, used;
30 void **obj;
31 struct {
32 u16 index;
33 u16 dist;
34 } near[0];
35};
36#define CPU_RMAP_DIST_INF 0xffff
37
38extern struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags);
39extern int cpu_rmap_put(struct cpu_rmap *rmap);
40
41extern int cpu_rmap_add(struct cpu_rmap *rmap, void *obj);
42extern int cpu_rmap_update(struct cpu_rmap *rmap, u16 index,
43 const struct cpumask *affinity);
44
45static inline u16 cpu_rmap_lookup_index(struct cpu_rmap *rmap, unsigned int cpu)
46{
47 return rmap->near[cpu].index;
48}
49
50static inline void *cpu_rmap_lookup_obj(struct cpu_rmap *rmap, unsigned int cpu)
51{
52 return rmap->obj[rmap->near[cpu].index];
53}
54
55/**
56 * alloc_irq_cpu_rmap - allocate CPU affinity reverse-map for IRQs
57 * @size: Number of objects to be mapped
58 *
59 * Must be called in process context.
60 */
61static inline struct cpu_rmap *alloc_irq_cpu_rmap(unsigned int size)
62{
63 return alloc_cpu_rmap(size, GFP_KERNEL);
64}
65extern void free_irq_cpu_rmap(struct cpu_rmap *rmap);
66
67extern int irq_cpu_rmap_add(struct cpu_rmap *rmap, int irq);
68
69#endif /* __LINUX_CPU_RMAP_H */
70