Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0-only */
       2             : #ifndef __LINUX_CPU_RMAP_H
       3             : #define __LINUX_CPU_RMAP_H
       4             : 
       5             : /*
       6             :  * cpu_rmap.c: CPU affinity reverse-map support
       7             :  * Copyright 2011 Solarflare Communications Inc.
       8             :  */
       9             : 
      10             : #include <linux/cpumask.h>
      11             : #include <linux/gfp.h>
      12             : #include <linux/slab.h>
      13             : #include <linux/kref.h>
      14             : 
      15             : /**
      16             :  * struct cpu_rmap - CPU affinity reverse-map
      17             :  * @refcount: kref for object
      18             :  * @size: Number of objects to be reverse-mapped
      19             :  * @used: Number of objects added
      20             :  * @obj: Pointer to array of object pointers
      21             :  * @near: For each CPU, the index and distance to the nearest object,
      22             :  *      based on affinity masks
      23             :  */
      24             : struct cpu_rmap {
      25             :         struct kref     refcount;
      26             :         u16             size, used;
      27             :         void            **obj;
      28             :         struct {
      29             :                 u16     index;
      30             :                 u16     dist;
      31             :         }               near[];
      32             : };
      33             : #define CPU_RMAP_DIST_INF 0xffff
      34             : 
      35             : extern struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags);
      36             : extern int cpu_rmap_put(struct cpu_rmap *rmap);
      37             : 
      38             : extern int cpu_rmap_add(struct cpu_rmap *rmap, void *obj);
      39             : extern int cpu_rmap_update(struct cpu_rmap *rmap, u16 index,
      40             :                            const struct cpumask *affinity);
      41             : 
      42           0 : static inline u16 cpu_rmap_lookup_index(struct cpu_rmap *rmap, unsigned int cpu)
      43             : {
      44           0 :         return rmap->near[cpu].index;
      45             : }
      46             : 
      47             : static inline void *cpu_rmap_lookup_obj(struct cpu_rmap *rmap, unsigned int cpu)
      48             : {
      49             :         return rmap->obj[rmap->near[cpu].index];
      50             : }
      51             : 
      52             : /**
      53             :  * alloc_irq_cpu_rmap - allocate CPU affinity reverse-map for IRQs
      54             :  * @size: Number of objects to be mapped
      55             :  *
      56             :  * Must be called in process context.
      57             :  */
      58             : static inline struct cpu_rmap *alloc_irq_cpu_rmap(unsigned int size)
      59             : {
      60             :         return alloc_cpu_rmap(size, GFP_KERNEL);
      61             : }
      62             : extern void free_irq_cpu_rmap(struct cpu_rmap *rmap);
      63             : 
      64             : extern int irq_cpu_rmap_add(struct cpu_rmap *rmap, int irq);
      65             : 
      66             : #endif /* __LINUX_CPU_RMAP_H */