2 * ACPI 3.0 based NUMA setup
3 * Copyright 2004 Andi Kleen, SuSE Labs.
5 * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
7 * Called from acpi_numa_init while reading the SRAT and SLIT tables.
8 * Assumes all memory regions belonging to a single proximity domain
9 * are in one chunk. Holes between them will be included in the node.
12 #include <linux/kernel.h>
13 #include <linux/acpi.h>
14 #include <linux/mmzone.h>
15 #include <linux/bitmap.h>
16 #include <linux/module.h>
17 #include <linux/topology.h>
18 #include <asm/proto.h>
21 static struct acpi_table_slit *acpi_slit;
23 static nodemask_t nodes_parsed __initdata;
24 static nodemask_t nodes_found __initdata;
25 static struct node nodes[MAX_NUMNODES] __initdata;
26 static __u8 pxm2node[256] = { [0 ... 255] = 0xff };
28 static __init int setup_node(int pxm)
30 unsigned node = pxm2node[pxm];
32 if (nodes_weight(nodes_found) >= MAX_NUMNODES)
34 node = first_unset_node(nodes_found);
35 node_set(node, nodes_found);
41 static __init int conflicting_nodes(unsigned long start, unsigned long end)
44 for_each_online_node(i) {
45 struct node *nd = &nodes[i];
46 if (nd->start == nd->end)
48 if (nd->end > start && nd->start < end)
50 if (nd->end == end && nd->start == start)
56 static __init void cutoff_node(int i, unsigned long start, unsigned long end)
58 struct node *nd = &nodes[i];
59 if (nd->start < start) {
61 if (nd->end < nd->start)
68 if (nd->start > nd->end)
73 static __init void bad_srat(void)
75 printk(KERN_ERR "SRAT: SRAT not used.\n");
79 static __init inline int srat_disabled(void)
81 return numa_off || acpi_numa < 0;
84 /* Callback for SLIT parsing */
85 void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
90 /* Callback for Proximity Domain -> LAPIC mapping */
92 acpi_numa_processor_affinity_init(struct acpi_table_processor_affinity *pa)
95 if (srat_disabled() || pa->flags.enabled == 0)
97 pxm = pa->proximity_domain;
98 node = setup_node(pxm);
100 printk(KERN_ERR "SRAT: Too many proximity domains %x\n", pxm);
104 if (pa->apic_id >= NR_CPUS) {
105 printk(KERN_ERR "SRAT: lapic %u too large.\n",
110 cpu_to_node[pa->apic_id] = node;
112 printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n",
113 pxm, pa->apic_id, node);
116 /* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
118 acpi_numa_memory_affinity_init(struct acpi_table_memory_affinity *ma)
121 unsigned long start, end;
125 if (srat_disabled() || ma->flags.enabled == 0)
127 /* hotplug bit is ignored for now */
128 pxm = ma->proximity_domain;
129 node = setup_node(pxm);
131 printk(KERN_ERR "SRAT: Too many proximity domains.\n");
135 start = ma->base_addr_lo | ((u64)ma->base_addr_hi << 32);
136 end = start + (ma->length_lo | ((u64)ma->length_hi << 32));
137 i = conflicting_nodes(start, end);
140 "SRAT: pxm %d overlap %lx-%lx with node %d(%Lx-%Lx)\n",
141 pxm, start, end, i, nodes[i].start, nodes[i].end);
146 if (!node_test_and_set(node, nodes_parsed)) {
150 if (start < nd->start)
155 if (!(nd->end & 0xfff))
157 printk(KERN_INFO "SRAT: Node %u PXM %u %Lx-%Lx\n", node, pxm,
161 void __init acpi_numa_arch_fixup(void) {}
163 /* Use the information discovered above to actually set up the nodes. */
164 int __init acpi_scan_nodes(unsigned long start, unsigned long end)
169 memnode_shift = compute_hash_shift(nodes, nodes_weight(nodes_parsed));
170 if (memnode_shift < 0) {
172 "SRAT: No NUMA node hash function found. Contact maintainer\n");
176 for (i = 0; i < MAX_NUMNODES; i++) {
177 if (!node_isset(i, nodes_parsed))
179 cutoff_node(i, start, end);
180 if (nodes[i].start == nodes[i].end) {
181 node_clear(i, nodes_parsed);
184 setup_node_bootmem(i, nodes[i].start, nodes[i].end);
186 for (i = 0; i < NR_CPUS; i++) {
187 if (cpu_to_node[i] == NUMA_NO_NODE)
189 if (!node_isset(cpu_to_node[i], nodes_parsed))
190 cpu_to_node[i] = NUMA_NO_NODE;
196 int node_to_pxm(int n)
199 if (pxm2node[n] == n)
201 for (i = 0; i < 256; i++)
202 if (pxm2node[i] == n)
207 int __node_distance(int a, int b)
212 return a == b ? 10 : 20;
213 index = acpi_slit->localities * node_to_pxm(a);
214 return acpi_slit->entry[index + node_to_pxm(b)];
217 EXPORT_SYMBOL(__node_distance);