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_ */
184
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