aboutsummaryrefslogtreecommitdiff
path: root/arch/x86_64/mm/srat.c
blob: 79e3e98bbf100a9e41f26763081c895aae46502e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
/*
 * ACPI 3.0 based NUMA setup
 * Copyright 2004 Andi Kleen, SuSE Labs.
 *
 * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
 *
 * Called from acpi_numa_init while reading the SRAT and SLIT tables.
 * Assumes all memory regions belonging to a single proximity domain
 * are in one chunk. Holes between them will be included in the node.
 */

#include <linux/kernel.h>
#include <linux/acpi.h>
#include <linux/mmzone.h>
#include <linux/bitmap.h>
#include <linux/module.h>
#include <linux/topology.h>
#include <asm/proto.h>
#include <asm/numa.h>

static struct acpi_table_slit *acpi_slit;

static nodemask_t nodes_parsed __initdata;
static nodemask_t nodes_found __initdata;
static struct node nodes[MAX_NUMNODES] __initdata;
static __u8  pxm2node[256] = { [0 ... 255] = 0xff };

/* Too small nodes confuse the VM badly. Usually they result
   from BIOS bugs. */
#define NODE_MIN_SIZE (4*1024*1024)

static int node_to_pxm(int n);

int pxm_to_node(int pxm)
{
	if ((unsigned)pxm >= 256)
		return 0;
	return pxm2node[pxm];
}

static __init int setup_node(int pxm)
{
	unsigned node = pxm2node[pxm];
	if (node == 0xff) {
		if (nodes_weight(nodes_found) >= MAX_NUMNODES)
			return -1;
		node = first_unset_node(nodes_found); 
		node_set(node, nodes_found);
		pxm2node[pxm] = node;
	}
	return pxm2node[pxm];
}

static __init int conflicting_nodes(unsigned long start, unsigned long end)
{
	int i;
	for_each_node_mask(i, nodes_parsed) {
		struct node *nd = &nodes[i];
		if (nd->start == nd->end)
			continue;
		if (nd->end > start && nd->start < end)
			return i;
		if (nd->end == end && nd->start == start)
			return i;
	}
	return -1;
}

static __init void cutoff_node(int i, unsigned long start, unsigned long end)
{
	struct node *nd = &nodes[i];
	if (nd->start < start) {
		nd->start = start;
		if (nd->end < nd->start)
			nd->start = nd->end;
	}
	if (nd->end > end) {
		nd->end = end;
		if (nd->start > nd->end)
			nd->start = nd->end;
	}
}

static __init void bad_srat(void)
{
	int i;
	printk(KERN_ERR "SRAT: SRAT not used.\n");
	acpi_numa = -1;
	for (i = 0; i < MAX_LOCAL_APIC; i++)
		apicid_to_node[i] = NUMA_NO_NODE;
}

static __init inline int srat_disabled(void)
{
	return numa_off || acpi_numa < 0;
}

/* Callback for SLIT parsing */
void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
{
	acpi_slit = slit;
}

/* Callback for Proximity Domain -> LAPIC mapping */
void __init
acpi_numa_processor_affinity_init(struct acpi_table_processor_affinity *pa)
{
	int pxm, node;
	if (srat_disabled() || pa->flags.enabled == 0)
		return;
	pxm = pa->proximity_domain;
	node = setup_node(pxm);
	if (node < 0) {
		printk(KERN_ERR "SRAT: Too many proximity domains %x\n", pxm);
		bad_srat();
		return;
	}
	apicid_to_node[pa->apic_id] = node;
	acpi_numa = 1;
	printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n",
	       pxm, pa->apic_id, node);
}

/* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
void __init
acpi_numa_memory_affinity_init(struct acpi_table_memory_affinity *ma)
{
	struct node *nd;
	unsigned long start, end;
	int node, pxm;
	int i;

	if (srat_disabled() || ma->flags.enabled == 0)
		return;
	pxm = ma->proximity_domain;
	node = setup_node(pxm);
	if (node < 0) {
		printk(KERN_ERR "SRAT: Too many proximity domains.\n");
		bad_srat();
		return;
	}
	start = ma->base_addr_lo | ((u64)ma->base_addr_hi << 32);
	end = start + (ma->length_lo | ((u64)ma->length_hi << 32));
	/* It is fine to add this area to the nodes data it will be used later*/
	if (ma->flags.hot_pluggable == 1)
		printk(KERN_INFO "SRAT: hot plug zone found %lx - %lx \n",
				start, end);
	i = conflicting_nodes(start, end);
	if (i == node) {
		printk(KERN_WARNING
		"SRAT: Warning: PXM %d (%lx-%lx) overlaps with itself (%Lx-%Lx)\n",
			pxm, start, end, nodes[i].start, nodes[i].end);
	} else if (i >= 0) {
		printk(KERN_ERR
		       "SRAT: PXM %d (%lx-%lx) overlaps with PXM %d (%Lx-%Lx)\n",
		       pxm, start, end, node_to_pxm(i),
			nodes[i].start, nodes[i].end);
		bad_srat();
		return;
	}
	nd = &nodes[node];
	if (!node_test_and_set(node, nodes_parsed)) {
		nd->start = start;
		nd->end = end;
	} else {
		if (start < nd->start)
			nd->start = start;
		if (nd->end < end)
			nd->end = end;
	}
	printk(KERN_INFO "SRAT: Node %u PXM %u %Lx-%Lx\n", node, pxm,
	       nd->start, nd->end);
}

static void unparse_node(int node)
{
	int i;
	node_clear(node, nodes_parsed);
	for (i = 0; i < MAX_LOCAL_APIC; i++) {
		if (apicid_to_node[i] == node)
			apicid_to_node[i] = NUMA_NO_NODE;
	}
}

void __init acpi_numa_arch_fixup(void) {}

/* Use the information discovered above to actually set up the nodes. */
int __init acpi_scan_nodes(unsigned long start, unsigned long end)
{
	int i;

	for (i = 0; i < MAX_NUMNODES; i++) {
 		cutoff_node(i, start, end);
		if ((nodes[i].end - nodes[i].start) < NODE_MIN_SIZE)
			unparse_node(i);
 	}

	if (acpi_numa <= 0)
		return -1;

	memnode_shift = compute_hash_shift(nodes, nodes_weight(nodes_parsed));
	if (memnode_shift < 0) {
		printk(KERN_ERR
		     "SRAT: No NUMA node hash function found. Contact maintainer\n");
		bad_srat();
		return -1;
	}

	/* Finally register nodes */
	for_each_node_mask(i, nodes_parsed)
		setup_node_bootmem(i, nodes[i].start, nodes[i].end);
	for (i = 0; i < NR_CPUS; i++) { 
		if (cpu_to_node[i] == NUMA_NO_NODE)
			continue;
		if (!node_isset(cpu_to_node[i], nodes_parsed))
			numa_set_node(i, NUMA_NO_NODE);
	}
	numa_init_array();
	return 0;
}

static int node_to_pxm(int n)
{
       int i;
       if (pxm2node[n] == n)
               return n;
       for (i = 0; i < 256; i++)
               if (pxm2node[i] == n)
                       return i;
       return 0;
}

int __node_distance(int a, int b)
{
	int index;

	if (!acpi_slit)
		return a == b ? 10 : 20;
	index = acpi_slit->localities * node_to_pxm(a);
	return acpi_slit->entry[index + node_to_pxm(b)];
}

EXPORT_SYMBOL(__node_distance);