Linux 3.9-rc4
[linux-2.6/cjktty.git] / include / linux / cpu_rmap.h
blob1739510d89943df23f193d5fb04332f47cdaf958
1 #ifndef __LINUX_CPU_RMAP_H
2 #define __LINUX_CPU_RMAP_H
4 /*
5 * cpu_rmap.c: CPU affinity reverse-map support
6 * Copyright 2011 Solarflare Communications Inc.
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.
13 #include <linux/cpumask.h>
14 #include <linux/gfp.h>
15 #include <linux/slab.h>
16 #include <linux/kref.h>
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
27 struct cpu_rmap {
28 struct kref refcount;
29 u16 size, used;
30 void **obj;
31 struct {
32 u16 index;
33 u16 dist;
34 } near[0];
36 #define CPU_RMAP_DIST_INF 0xffff
38 extern struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags);
39 extern int cpu_rmap_put(struct cpu_rmap *rmap);
41 extern int cpu_rmap_add(struct cpu_rmap *rmap, void *obj);
42 extern int cpu_rmap_update(struct cpu_rmap *rmap, u16 index,
43 const struct cpumask *affinity);
45 static inline u16 cpu_rmap_lookup_index(struct cpu_rmap *rmap, unsigned int cpu)
47 return rmap->near[cpu].index;
50 static inline void *cpu_rmap_lookup_obj(struct cpu_rmap *rmap, unsigned int cpu)
52 return rmap->obj[rmap->near[cpu].index];
55 #ifdef CONFIG_GENERIC_HARDIRQS
57 /**
58 * alloc_irq_cpu_rmap - allocate CPU affinity reverse-map for IRQs
59 * @size: Number of objects to be mapped
61 * Must be called in process context.
63 static inline struct cpu_rmap *alloc_irq_cpu_rmap(unsigned int size)
65 return alloc_cpu_rmap(size, GFP_KERNEL);
67 extern void free_irq_cpu_rmap(struct cpu_rmap *rmap);
69 extern int irq_cpu_rmap_add(struct cpu_rmap *rmap, int irq);
71 #endif
72 #endif /* __LINUX_CPU_RMAP_H */