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/list.h>
  20
  21 /**
  22  * struct access_coordinate - generic performance coordinates container
  23  *
  24  * @read_bandwidth:     Read bandwidth in MB/s
  25  * @write_bandwidth:    Write bandwidth in MB/s
  26  * @read_latency:       Read latency in nanoseconds
  27  * @write_latency:      Write latency in nanoseconds
  28  */
  29 struct access_coordinate {
  30         unsigned int read_bandwidth;
  31         unsigned int write_bandwidth;
  32         unsigned int read_latency;
  33         unsigned int write_latency;
  34 };
  35
  36 /*
  37  * ACCESS_COORDINATE_LOCAL correlates to ACCESS CLASS 0
  38  *      - access_coordinate between target node and nearest initiator node
  39  * ACCESS_COORDINATE_CPU correlates to ACCESS CLASS 1
  40  *      - access_coordinate between target node and nearest CPU node
  41  */
  42 enum access_coordinate_class {
  43         ACCESS_COORDINATE_LOCAL,
  44         ACCESS_COORDINATE_CPU,
  45         ACCESS_COORDINATE_MAX
  46 };
  47
  48 enum cache_indexing {
  49         NODE_CACHE_DIRECT_MAP,
  50         NODE_CACHE_INDEXED,
  51         NODE_CACHE_OTHER,
  52 };
  53
  54 enum cache_write_policy {
  55         NODE_CACHE_WRITE_BACK,
  56         NODE_CACHE_WRITE_THROUGH,
  57         NODE_CACHE_WRITE_OTHER,
  58 };
  59
  60 /**
  61  * struct node_cache_attrs - system memory caching attributes
  62  *
  63  * @indexing:           The ways memory blocks may be placed in cache
  64  * @write_policy:       Write back or write through policy
  65  * @size:               Total size of cache in bytes
  66  * @line_size:          Number of bytes fetched on a cache miss
  67  * @level:              The cache hierarchy level
  68  */
  69 struct node_cache_attrs {
  70         enum cache_indexing indexing;
  71         enum cache_write_policy write_policy;
  72         u64 size;
  73         u16 line_size;
  74         u8 level;
  75 };
  76
  77 #ifdef CONFIG_HMEM_REPORTING
  78 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs);
  79 void node_set_perf_attrs(unsigned int nid, struct access_coordinate *coord,
  80                          enum access_coordinate_class access);
  81 #else
  82 static inline void node_add_cache(unsigned int nid,
  83                                   struct node_cache_attrs *cache_attrs)
  84 {
  85 }
  86
  87 static inline void node_set_perf_attrs(unsigned int nid,
  88                                        struct access_coordinate *coord,
  89                                        enum access_coordinate_class access)
  90 {
  91 }
  92 #endif
  93
  94 struct node {
  95         struct device   dev;
  96         struct list_head access_list;
  97 #ifdef CONFIG_HMEM_REPORTING
  98         struct list_head cache_attrs;
  99         struct device *cache_dev;
 100 #endif
 101 };
 102
 103 struct memory_block;
 104 extern struct node *node_devices[];
 105
 106 #if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_NUMA)
 107 void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
 108                                        unsigned long end_pfn,
 109                                        enum meminit_context context);
 110 #else
 111 static inline void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
 112                                                      unsigned long end_pfn,
 113                                                      enum meminit_context context)
 114 {
 115 }
 116 #endif
 117
 118 extern void unregister_node(struct node *node);
 119 #ifdef CONFIG_NUMA
 120 extern void node_dev_init(void);
 121 /* Core of the node registration - only memory hotplug should use this */
 122 extern int __register_one_node(int nid);
 123
 124 /* Registers an online node */
 125 static inline int register_one_node(int nid)
 126 {
 127         int error = 0;
 128
 129         if (node_online(nid)) {
 130                 struct pglist_data *pgdat = NODE_DATA(nid);
 131                 unsigned long start_pfn = pgdat->node_start_pfn;
 132                 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
 133
 134                 error = __register_one_node(nid);
 135                 if (error)
 136                         return error;
 137                 register_memory_blocks_under_node(nid, start_pfn, end_pfn,
 138                                                   MEMINIT_EARLY);
 139         }
 140
 141         return error;
 142 }
 143
 144 extern void unregister_one_node(int nid);
 145 extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
 146 extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
 147 extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
 148
 149 extern int register_memory_node_under_compute_node(unsigned int mem_nid,
 150                                                    unsigned int cpu_nid,
 151                                                    enum access_coordinate_class access);
 152 #else
 153 static inline void node_dev_init(void)
 154 {
 155 }
 156 static inline int __register_one_node(int nid)
 157 {
 158         return 0;
 159 }
 160 static inline int register_one_node(int nid)
 161 {
 162         return 0;
 163 }
 164 static inline int unregister_one_node(int nid)
 165 {
 166         return 0;
 167 }
 168 static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
 169 {
 170         return 0;
 171 }
 172 static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
 173 {
 174         return 0;
 175 }
 176 static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
 177 {
 178 }
 179 #endif
 180
 181 #define to_node(device) container_of(device, struct node, dev)
 182
 183 #endif /* _LINUX_NODE_H_ */