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
22/**
23 * struct access_coordinate - generic performance coordinates container
24 *
25 * @read_bandwidth: Read bandwidth in MB/s
26 * @write_bandwidth: Write bandwidth in MB/s
27 * @read_latency: Read latency in nanoseconds
28 * @write_latency: Write latency in nanoseconds
29 */
30struct access_coordinate {
31 unsigned int read_bandwidth;
32 unsigned int write_bandwidth;
33 unsigned int read_latency;
34 unsigned int write_latency;
35};
36
37/*
38 * ACCESS_COORDINATE_LOCAL correlates to ACCESS CLASS 0
39 * - access_coordinate between target node and nearest initiator node
40 * ACCESS_COORDINATE_CPU correlates to ACCESS CLASS 1
41 * - access_coordinate between target node and nearest CPU node
42 */
43enum access_coordinate_class {
44 ACCESS_COORDINATE_LOCAL,
45 ACCESS_COORDINATE_CPU,
46 ACCESS_COORDINATE_MAX
47};
48
49enum cache_indexing {
50 NODE_CACHE_DIRECT_MAP,
51 NODE_CACHE_INDEXED,
52 NODE_CACHE_OTHER,
53};
54
55enum cache_write_policy {
56 NODE_CACHE_WRITE_BACK,
57 NODE_CACHE_WRITE_THROUGH,
58 NODE_CACHE_WRITE_OTHER,
59};
60
61/**
62 * struct node_cache_attrs - system memory caching attributes
63 *
64 * @indexing: The ways memory blocks may be placed in cache
65 * @write_policy: Write back or write through policy
66 * @size: Total size of cache in bytes
67 * @line_size: Number of bytes fetched on a cache miss
68 * @level: The cache hierarchy level
69 */
70struct node_cache_attrs {
71 enum cache_indexing indexing;
72 enum cache_write_policy write_policy;
73 u64 size;
74 u16 line_size;
75 u8 level;
76};
77
78#ifdef CONFIG_HMEM_REPORTING
79void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs);
80void node_set_perf_attrs(unsigned int nid, struct access_coordinate *coord,
81 enum access_coordinate_class access);
82#else
83static inline void node_add_cache(unsigned int nid,
84 struct node_cache_attrs *cache_attrs)
85{
86}
87
88static inline void node_set_perf_attrs(unsigned int nid,
89 struct access_coordinate *coord,
90 enum access_coordinate_class access)
91{
92}
93#endif
94
95struct node {
96 struct device dev;
97 struct list_head access_list;
98#ifdef CONFIG_HMEM_REPORTING
99 struct list_head cache_attrs;
100 struct device *cache_dev;
101#endif
102};
103
104struct memory_block;
105extern struct node *node_devices[];
106
107#if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_NUMA)
108void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
109 unsigned long end_pfn,
110 enum meminit_context context);
111#else
112static inline void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
113 unsigned long end_pfn,
114 enum meminit_context context)
115{
116}
117#endif
118
119extern void unregister_node(struct node *node);
120#ifdef CONFIG_NUMA
121extern void node_dev_init(void);
122/* Core of the node registration - only memory hotplug should use this */
123extern int __register_one_node(int nid);
124
125/* Registers an online node */
126static inline int register_one_node(int nid)
127{
128 int error = 0;
129
130 if (node_online(nid)) {
131 struct pglist_data *pgdat = NODE_DATA(nid);
132 unsigned long start_pfn = pgdat->node_start_pfn;
133 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
134
135 error = __register_one_node(nid);
136 if (error)
137 return error;
138 register_memory_blocks_under_node(nid, start_pfn, end_pfn,
139 context: MEMINIT_EARLY);
140 }
141
142 return error;
143}
144
145extern void unregister_one_node(int nid);
146extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
147extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
148extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
149
150extern int register_memory_node_under_compute_node(unsigned int mem_nid,
151 unsigned int cpu_nid,
152 enum access_coordinate_class access);
153#else
154static inline void node_dev_init(void)
155{
156}
157static inline int __register_one_node(int nid)
158{
159 return 0;
160}
161static inline int register_one_node(int nid)
162{
163 return 0;
164}
165static inline int unregister_one_node(int nid)
166{
167 return 0;
168}
169static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
170{
171 return 0;
172}
173static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
174{
175 return 0;
176}
177static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
178{
179}
180#endif
181
182#define to_node(device) container_of(device, struct node, dev)
183
184#endif /* _LINUX_NODE_H_ */
185

source code of linux/include/linux/node.h