LXR linux/include/linux/node.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * include/linux/node.h - generic node definition
   4 *
   5 * This is mainly for topological representation. We define the 
   6 * basic 'struct node' here, which can be embedded in per-arch 
   7 * definitions of processors.
   8 *
   9 * Basic handling of the devices is done in drivers/base/node.c
  10 * and system devices are handled in drivers/base/sys.c. 
  11 *
  12 * Nodes are exported via driverfs in the class/node/devices/
  13 * directory. 
  14 */
  15#ifndef _LINUX_NODE_H_
  16#define _LINUX_NODE_H_
  17
  18#include <linux/device.h>
  19#include <linux/cpumask.h>
  20#include <linux/list.h>
  21#include <linux/workqueue.h>
  22
  23/**
  24 * struct node_hmem_attrs - heterogeneous memory performance attributes
  25 *
  26 * @read_bandwidth:     Read bandwidth in MB/s
  27 * @write_bandwidth:    Write bandwidth in MB/s
  28 * @read_latency:       Read latency in nanoseconds
  29 * @write_latency:      Write latency in nanoseconds
  30 */
  31struct node_hmem_attrs {
  32        unsigned int read_bandwidth;
  33        unsigned int write_bandwidth;
  34        unsigned int read_latency;
  35        unsigned int write_latency;
  36};
  37
  38enum cache_indexing {
  39        NODE_CACHE_DIRECT_MAP,
  40        NODE_CACHE_INDEXED,
  41        NODE_CACHE_OTHER,
  42};
  43
  44enum cache_write_policy {
  45        NODE_CACHE_WRITE_BACK,
  46        NODE_CACHE_WRITE_THROUGH,
  47        NODE_CACHE_WRITE_OTHER,
  48};
  49
  50/**
  51 * struct node_cache_attrs - system memory caching attributes
  52 *
  53 * @indexing:           The ways memory blocks may be placed in cache
  54 * @write_policy:       Write back or write through policy
  55 * @size:               Total size of cache in bytes
  56 * @line_size:          Number of bytes fetched on a cache miss
  57 * @level:              The cache hierarchy level
  58 */
  59struct node_cache_attrs {
  60        enum cache_indexing indexing;
  61        enum cache_write_policy write_policy;
  62        u64 size;
  63        u16 line_size;
  64        u8 level;
  65};
  66
  67#ifdef CONFIG_HMEM_REPORTING
  68void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs);
  69void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
  70                         unsigned access);
  71#else
  72static inline void node_add_cache(unsigned int nid,
  73                                  struct node_cache_attrs *cache_attrs)
  74{
  75}
  76
  77static inline void node_set_perf_attrs(unsigned int nid,
  78                                       struct node_hmem_attrs *hmem_attrs,
  79                                       unsigned access)
  80{
  81}
  82#endif
  83
  84struct node {
  85        struct device   dev;
  86        struct list_head access_list;
  87
  88#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
  89        struct work_struct      node_work;
  90#endif
  91#ifdef CONFIG_HMEM_REPORTING
  92        struct list_head cache_attrs;
  93        struct device *cache_dev;
  94#endif
  95};
  96
  97struct memory_block;
  98extern struct node *node_devices[];
  99typedef  void (*node_registration_func_t)(struct node *);
 100
 101#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA)
 102int link_mem_sections(int nid, unsigned long start_pfn,
 103                      unsigned long end_pfn,
 104                      enum meminit_context context);
 105#else
 106static inline int link_mem_sections(int nid, unsigned long start_pfn,
 107                                    unsigned long end_pfn,
 108                                    enum meminit_context context)
 109{
 110        return 0;
 111}
 112#endif
 113
 114extern void unregister_node(struct node *node);
 115#ifdef CONFIG_NUMA
 116/* Core of the node registration - only memory hotplug should use this */
 117extern int __register_one_node(int nid);
 118
 119/* Registers an online node */
 120static inline int register_one_node(int nid)
 121{
 122        int error = 0;
 123
 124        if (node_online(nid)) {
 125                struct pglist_data *pgdat = NODE_DATA(nid);
 126                unsigned long start_pfn = pgdat->node_start_pfn;
 127                unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
 128
 129                error = __register_one_node(nid);
 130                if (error)
 131                        return error;
 132                /* link memory sections under this node */
 133                error = link_mem_sections(nid, start_pfn, end_pfn,
 134                                          MEMINIT_EARLY);
 135        }
 136
 137        return error;
 138}
 139
 140extern void unregister_one_node(int nid);
 141extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
 142extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
 143extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
 144
 145extern int register_memory_node_under_compute_node(unsigned int mem_nid,
 146                                                   unsigned int cpu_nid,
 147                                                   unsigned access);
 148
 149#ifdef CONFIG_HUGETLBFS
 150extern void register_hugetlbfs_with_node(node_registration_func_t doregister,
 151                                         node_registration_func_t unregister);
 152#endif
 153#else
 154static inline int __register_one_node(int nid)
 155{
 156        return 0;
 157}
 158static inline int register_one_node(int nid)
 159{
 160        return 0;
 161}
 162static inline int unregister_one_node(int nid)
 163{
 164        return 0;
 165}
 166static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
 167{
 168        return 0;
 169}
 170static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
 171{
 172        return 0;
 173}
 174static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
 175{
 176}
 177
 178static inline void register_hugetlbfs_with_node(node_registration_func_t reg,
 179                                                node_registration_func_t unreg)
 180{
 181}
 182#endif
 183
 184#define to_node(device) container_of(device, struct node, dev)
 185
 186#endif /* _LINUX_NODE_H_ */
 187