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 <linux/bootmem.h>
20 #include <asm/proto.h>
23 #include <asm/genapic.h>
25 int acpi_numa __initdata
;
27 static struct acpi_table_slit
*acpi_slit
;
29 static nodemask_t nodes_parsed __initdata
;
30 static struct bootnode nodes
[MAX_NUMNODES
] __initdata
;
31 static struct bootnode nodes_add
[MAX_NUMNODES
];
32 static int found_add_area __initdata
;
33 int hotadd_percent __initdata
= 0;
35 static int num_node_memblks __initdata
;
36 static struct bootnode node_memblk_range
[NR_NODE_MEMBLKS
] __initdata
;
37 static int memblk_nodeid
[NR_NODE_MEMBLKS
] __initdata
;
39 /* Too small nodes confuse the VM badly. Usually they result
41 #define NODE_MIN_SIZE (4*1024*1024)
43 static __init
int setup_node(int pxm
)
45 return acpi_map_pxm_to_node(pxm
);
48 static __init
int conflicting_memblks(unsigned long start
, unsigned long end
)
51 for (i
= 0; i
< num_node_memblks
; i
++) {
52 struct bootnode
*nd
= &node_memblk_range
[i
];
53 if (nd
->start
== nd
->end
)
55 if (nd
->end
> start
&& nd
->start
< end
)
56 return memblk_nodeid
[i
];
57 if (nd
->end
== end
&& nd
->start
== start
)
58 return memblk_nodeid
[i
];
63 static __init
void cutoff_node(int i
, unsigned long start
, unsigned long end
)
65 struct bootnode
*nd
= &nodes
[i
];
70 if (nd
->start
< start
) {
72 if (nd
->end
< nd
->start
)
77 if (nd
->start
> nd
->end
)
82 static __init
void bad_srat(void)
85 printk(KERN_ERR
"SRAT: SRAT not used.\n");
88 for (i
= 0; i
< MAX_LOCAL_APIC
; i
++)
89 apicid_to_node
[i
] = NUMA_NO_NODE
;
90 for (i
= 0; i
< MAX_NUMNODES
; i
++)
91 nodes_add
[i
].start
= nodes
[i
].end
= 0;
92 remove_all_active_ranges();
95 static __init
inline int srat_disabled(void)
97 return numa_off
|| acpi_numa
< 0;
101 * A lot of BIOS fill in 10 (= no distance) everywhere. This messes
102 * up the NUMA heuristics which wants the local node to have a smaller
103 * distance than the others.
104 * Do some quick checks here and only use the SLIT if it passes.
106 static __init
int slit_valid(struct acpi_table_slit
*slit
)
109 int d
= slit
->locality_count
;
110 for (i
= 0; i
< d
; i
++) {
111 for (j
= 0; j
< d
; j
++) {
112 u8 val
= slit
->entry
[d
*i
+ j
];
114 if (val
!= LOCAL_DISTANCE
)
116 } else if (val
<= LOCAL_DISTANCE
)
123 /* Callback for SLIT parsing */
124 void __init
acpi_numa_slit_init(struct acpi_table_slit
*slit
)
126 if (!slit_valid(slit
)) {
127 printk(KERN_INFO
"ACPI: SLIT table looks invalid. Not used.\n");
133 /* Callback for Proximity Domain -> LAPIC mapping */
135 acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity
*pa
)
142 if (pa
->header
.length
!= sizeof(struct acpi_srat_cpu_affinity
)) {
146 if ((pa
->flags
& ACPI_SRAT_CPU_ENABLED
) == 0)
148 pxm
= pa
->proximity_domain_lo
;
149 node
= setup_node(pxm
);
151 printk(KERN_ERR
"SRAT: Too many proximity domains %x\n", pxm
);
157 apic_id
= (pa
->apic_id
<< 8) | pa
->local_sapic_eid
;
159 apic_id
= pa
->apic_id
;
160 apicid_to_node
[apic_id
] = node
;
162 printk(KERN_INFO
"SRAT: PXM %u -> APIC %u -> Node %u\n",
166 static int update_end_of_memory(unsigned long end
) {return -1;}
167 static int hotadd_enough_memory(struct bootnode
*nd
) {return 1;}
168 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
169 static inline int save_add_info(void) {return 1;}
171 static inline int save_add_info(void) {return 0;}
174 * Update nodes_add and decide if to include add are in the zone.
175 * Both SPARSE and RESERVE need nodes_add information.
176 * This code supports one contiguous hot add area per node.
179 reserve_hotadd(int node
, unsigned long start
, unsigned long end
)
181 unsigned long s_pfn
= start
>> PAGE_SHIFT
;
182 unsigned long e_pfn
= end
>> PAGE_SHIFT
;
183 int ret
= 0, changed
= 0;
184 struct bootnode
*nd
= &nodes_add
[node
];
186 /* I had some trouble with strange memory hotadd regions breaking
187 the boot. Be very strict here and reject anything unexpected.
188 If you want working memory hotadd write correct SRATs.
190 The node size check is a basic sanity check to guard against
192 if ((signed long)(end
- start
) < NODE_MIN_SIZE
) {
193 printk(KERN_ERR
"SRAT: Hotplug area too small\n");
197 /* This check might be a bit too strict, but I'm keeping it for now. */
198 if (absent_pages_in_range(s_pfn
, e_pfn
) != e_pfn
- s_pfn
) {
200 "SRAT: Hotplug area %lu -> %lu has existing memory\n",
205 if (!hotadd_enough_memory(&nodes_add
[node
])) {
206 printk(KERN_ERR
"SRAT: Hotplug area too large\n");
212 if (nd
->start
== nd
->end
) {
217 if (nd
->start
== end
) {
221 if (nd
->end
== start
) {
226 printk(KERN_ERR
"SRAT: Hotplug zone not continuous. Partly ignored\n");
229 ret
= update_end_of_memory(nd
->end
);
232 printk(KERN_INFO
"SRAT: hot plug zone found %Lx - %Lx\n", nd
->start
, nd
->end
);
236 /* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
238 acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity
*ma
)
240 struct bootnode
*nd
, oldnode
;
241 unsigned long start
, end
;
247 if (ma
->header
.length
!= sizeof(struct acpi_srat_mem_affinity
)) {
251 if ((ma
->flags
& ACPI_SRAT_MEM_ENABLED
) == 0)
254 if ((ma
->flags
& ACPI_SRAT_MEM_HOT_PLUGGABLE
) && !save_add_info())
256 start
= ma
->base_address
;
257 end
= start
+ ma
->length
;
258 pxm
= ma
->proximity_domain
;
259 node
= setup_node(pxm
);
261 printk(KERN_ERR
"SRAT: Too many proximity domains.\n");
265 i
= conflicting_memblks(start
, end
);
268 "SRAT: Warning: PXM %d (%lx-%lx) overlaps with itself (%Lx-%Lx)\n",
269 pxm
, start
, end
, nodes
[i
].start
, nodes
[i
].end
);
272 "SRAT: PXM %d (%lx-%lx) overlaps with PXM %d (%Lx-%Lx)\n",
273 pxm
, start
, end
, node_to_pxm(i
),
274 nodes
[i
].start
, nodes
[i
].end
);
280 if (!node_test_and_set(node
, nodes_parsed
)) {
284 if (start
< nd
->start
)
290 printk(KERN_INFO
"SRAT: Node %u PXM %u %lx-%lx\n", node
, pxm
,
292 e820_register_active_regions(node
, start
>> PAGE_SHIFT
,
294 push_node_boundaries(node
, nd
->start
>> PAGE_SHIFT
,
295 nd
->end
>> PAGE_SHIFT
);
297 if ((ma
->flags
& ACPI_SRAT_MEM_HOT_PLUGGABLE
) &&
298 (reserve_hotadd(node
, start
, end
) < 0)) {
299 /* Ignore hotadd region. Undo damage */
300 printk(KERN_NOTICE
"SRAT: Hotplug region ignored\n");
302 if ((nd
->start
| nd
->end
) == 0)
303 node_clear(node
, nodes_parsed
);
306 node_memblk_range
[num_node_memblks
].start
= start
;
307 node_memblk_range
[num_node_memblks
].end
= end
;
308 memblk_nodeid
[num_node_memblks
] = node
;
312 /* Sanity check to catch more bad SRATs (they are amazingly common).
313 Make sure the PXMs cover all memory. */
314 static int __init
nodes_cover_memory(const struct bootnode
*nodes
)
317 unsigned long pxmram
, e820ram
;
320 for_each_node_mask(i
, nodes_parsed
) {
321 unsigned long s
= nodes
[i
].start
>> PAGE_SHIFT
;
322 unsigned long e
= nodes
[i
].end
>> PAGE_SHIFT
;
324 pxmram
-= absent_pages_in_range(s
, e
);
325 if ((long)pxmram
< 0)
329 e820ram
= end_pfn
- absent_pages_in_range(0, end_pfn
);
330 /* We seem to lose 3 pages somewhere. Allow a bit of slack. */
331 if ((long)(e820ram
- pxmram
) >= 1*1024*1024) {
333 "SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n",
334 (pxmram
<< PAGE_SHIFT
) >> 20,
335 (e820ram
<< PAGE_SHIFT
) >> 20);
341 static void __init
unparse_node(int node
)
344 node_clear(node
, nodes_parsed
);
345 for (i
= 0; i
< MAX_LOCAL_APIC
; i
++) {
346 if (apicid_to_node
[i
] == node
)
347 apicid_to_node
[i
] = NUMA_NO_NODE
;
351 void __init
acpi_numa_arch_fixup(void) {}
353 /* Use the information discovered above to actually set up the nodes. */
354 int __init
acpi_scan_nodes(unsigned long start
, unsigned long end
)
361 /* First clean up the node list */
362 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
363 cutoff_node(i
, start
, end
);
365 * don't confuse VM with a node that doesn't have the
369 (nodes
[i
].end
- nodes
[i
].start
) < NODE_MIN_SIZE
) {
375 if (!nodes_cover_memory(nodes
)) {
380 memnode_shift
= compute_hash_shift(node_memblk_range
, num_node_memblks
,
382 if (memnode_shift
< 0) {
384 "SRAT: No NUMA node hash function found. Contact maintainer\n");
389 node_possible_map
= nodes_parsed
;
391 /* Finally register nodes */
392 for_each_node_mask(i
, node_possible_map
)
393 setup_node_bootmem(i
, nodes
[i
].start
, nodes
[i
].end
);
394 /* Try again in case setup_node_bootmem missed one due
395 to missing bootmem */
396 for_each_node_mask(i
, node_possible_map
)
398 setup_node_bootmem(i
, nodes
[i
].start
, nodes
[i
].end
);
400 for (i
= 0; i
< NR_CPUS
; i
++) {
401 int node
= early_cpu_to_node(i
);
403 if (node
== NUMA_NO_NODE
)
405 if (!node_isset(node
, node_possible_map
))
406 numa_set_node(i
, NUMA_NO_NODE
);
412 #ifdef CONFIG_NUMA_EMU
413 static int fake_node_to_pxm_map
[MAX_NUMNODES
] __initdata
= {
414 [0 ... MAX_NUMNODES
-1] = PXM_INVAL
416 static s16 fake_apicid_to_node
[MAX_LOCAL_APIC
] __initdata
= {
417 [0 ... MAX_LOCAL_APIC
-1] = NUMA_NO_NODE
419 static int __init
find_node_by_addr(unsigned long addr
)
421 int ret
= NUMA_NO_NODE
;
424 for_each_node_mask(i
, nodes_parsed
) {
426 * Find the real node that this emulated node appears on. For
427 * the sake of simplicity, we only use a real node's starting
428 * address to determine which emulated node it appears on.
430 if (addr
>= nodes
[i
].start
&& addr
< nodes
[i
].end
) {
439 * In NUMA emulation, we need to setup proximity domain (_PXM) to node ID
440 * mappings that respect the real ACPI topology but reflect our emulated
441 * environment. For each emulated node, we find which real node it appears on
442 * and create PXM to NID mappings for those fake nodes which mirror that
443 * locality. SLIT will now represent the correct distances between emulated
444 * nodes as a result of the real topology.
446 void __init
acpi_fake_nodes(const struct bootnode
*fake_nodes
, int num_nodes
)
450 printk(KERN_INFO
"Faking PXM affinity for fake nodes on real "
452 for (i
= 0; i
< num_nodes
; i
++) {
455 nid
= find_node_by_addr(fake_nodes
[i
].start
);
456 if (nid
== NUMA_NO_NODE
)
458 pxm
= node_to_pxm(nid
);
459 if (pxm
== PXM_INVAL
)
461 fake_node_to_pxm_map
[i
] = pxm
;
463 * For each apicid_to_node mapping that exists for this real
464 * node, it must now point to the fake node ID.
466 for (j
= 0; j
< MAX_LOCAL_APIC
; j
++)
467 if (apicid_to_node
[j
] == nid
)
468 fake_apicid_to_node
[j
] = i
;
470 for (i
= 0; i
< num_nodes
; i
++)
471 __acpi_map_pxm_to_node(fake_node_to_pxm_map
[i
], i
);
472 memcpy(apicid_to_node
, fake_apicid_to_node
, sizeof(apicid_to_node
));
474 nodes_clear(nodes_parsed
);
475 for (i
= 0; i
< num_nodes
; i
++)
476 if (fake_nodes
[i
].start
!= fake_nodes
[i
].end
)
477 node_set(i
, nodes_parsed
);
478 WARN_ON(!nodes_cover_memory(fake_nodes
));
481 static int null_slit_node_compare(int a
, int b
)
483 return node_to_pxm(a
) == node_to_pxm(b
);
486 static int null_slit_node_compare(int a
, int b
)
490 #endif /* CONFIG_NUMA_EMU */
492 void __init
srat_reserve_add_area(int nodeid
)
494 if (found_add_area
&& nodes_add
[nodeid
].end
) {
497 printk(KERN_INFO
"SRAT: Reserving hot-add memory space "
498 "for node %d at %Lx-%Lx\n",
499 nodeid
, nodes_add
[nodeid
].start
, nodes_add
[nodeid
].end
);
500 total_mb
= (nodes_add
[nodeid
].end
- nodes_add
[nodeid
].start
)
502 total_mb
*= sizeof(struct page
);
504 printk(KERN_INFO
"SRAT: This will cost you %Lu MB of "
505 "pre-allocated memory.\n", (unsigned long long)total_mb
);
506 reserve_bootmem_node(NODE_DATA(nodeid
), nodes_add
[nodeid
].start
,
507 nodes_add
[nodeid
].end
- nodes_add
[nodeid
].start
,
512 int __node_distance(int a
, int b
)
517 return null_slit_node_compare(a
, b
) ? LOCAL_DISTANCE
:
519 index
= acpi_slit
->locality_count
* node_to_pxm(a
);
520 return acpi_slit
->entry
[index
+ node_to_pxm(b
)];
523 EXPORT_SYMBOL(__node_distance
);
525 int memory_add_physaddr_to_nid(u64 start
)
530 if (nodes_add
[i
].start
<= start
&& nodes_add
[i
].end
> start
)
535 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid
);