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>
24 int acpi_numa __initdata
;
26 static struct acpi_table_slit
*acpi_slit
;
28 static nodemask_t nodes_parsed __initdata
;
29 static struct bootnode nodes
[MAX_NUMNODES
] __initdata
;
30 static struct bootnode nodes_add
[MAX_NUMNODES
];
31 static int found_add_area __initdata
;
32 int hotadd_percent __initdata
= 0;
34 /* Too small nodes confuse the VM badly. Usually they result
36 #define NODE_MIN_SIZE (4*1024*1024)
38 static __init
int setup_node(int pxm
)
40 return acpi_map_pxm_to_node(pxm
);
43 static __init
int conflicting_nodes(unsigned long start
, unsigned long end
)
46 for_each_node_mask(i
, nodes_parsed
) {
47 struct bootnode
*nd
= &nodes
[i
];
48 if (nd
->start
== nd
->end
)
50 if (nd
->end
> start
&& nd
->start
< end
)
52 if (nd
->end
== end
&& nd
->start
== start
)
58 static __init
void cutoff_node(int i
, unsigned long start
, unsigned long end
)
60 struct bootnode
*nd
= &nodes
[i
];
65 if (nd
->start
< start
) {
67 if (nd
->end
< nd
->start
)
72 if (nd
->start
> nd
->end
)
77 static __init
void bad_srat(void)
80 printk(KERN_ERR
"SRAT: SRAT not used.\n");
83 for (i
= 0; i
< MAX_LOCAL_APIC
; i
++)
84 apicid_to_node
[i
] = NUMA_NO_NODE
;
85 for (i
= 0; i
< MAX_NUMNODES
; i
++)
86 nodes_add
[i
].start
= nodes
[i
].end
= 0;
87 remove_all_active_ranges();
90 static __init
inline int srat_disabled(void)
92 return numa_off
|| acpi_numa
< 0;
96 * A lot of BIOS fill in 10 (= no distance) everywhere. This messes
97 * up the NUMA heuristics which wants the local node to have a smaller
98 * distance than the others.
99 * Do some quick checks here and only use the SLIT if it passes.
101 static __init
int slit_valid(struct acpi_table_slit
*slit
)
104 int d
= slit
->locality_count
;
105 for (i
= 0; i
< d
; i
++) {
106 for (j
= 0; j
< d
; j
++) {
107 u8 val
= slit
->entry
[d
*i
+ j
];
109 if (val
!= LOCAL_DISTANCE
)
111 } else if (val
<= LOCAL_DISTANCE
)
118 /* Callback for SLIT parsing */
119 void __init
acpi_numa_slit_init(struct acpi_table_slit
*slit
)
121 if (!slit_valid(slit
)) {
122 printk(KERN_INFO
"ACPI: SLIT table looks invalid. Not used.\n");
128 /* Callback for Proximity Domain -> LAPIC mapping */
130 acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity
*pa
)
135 apic_id
= pa
->apic_id
;
138 if (pa
->header
.length
!= sizeof(struct acpi_srat_cpu_affinity
)) {
142 if ((pa
->flags
& ACPI_SRAT_CPU_ENABLED
) == 0)
144 pxm
= pa
->proximity_domain_lo
;
145 node
= setup_node(pxm
);
147 printk(KERN_ERR
"SRAT: Too many proximity domains %x\n", pxm
);
151 apicid_to_node
[apic_id
] = node
;
153 printk(KERN_INFO
"SRAT: PXM %u -> APIC %u -> Node %u\n",
157 int update_end_of_memory(unsigned long end
) {return -1;}
158 static int hotadd_enough_memory(struct bootnode
*nd
) {return 1;}
159 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
160 static inline int save_add_info(void) {return 1;}
162 static inline int save_add_info(void) {return 0;}
165 * Update nodes_add and decide if to include add are in the zone.
166 * Both SPARSE and RESERVE need nodes_add information.
167 * This code supports one contiguous hot add area per node.
170 reserve_hotadd(int node
, unsigned long start
, unsigned long end
)
172 unsigned long s_pfn
= start
>> PAGE_SHIFT
;
173 unsigned long e_pfn
= end
>> PAGE_SHIFT
;
174 int ret
= 0, changed
= 0;
175 struct bootnode
*nd
= &nodes_add
[node
];
177 /* I had some trouble with strange memory hotadd regions breaking
178 the boot. Be very strict here and reject anything unexpected.
179 If you want working memory hotadd write correct SRATs.
181 The node size check is a basic sanity check to guard against
183 if ((signed long)(end
- start
) < NODE_MIN_SIZE
) {
184 printk(KERN_ERR
"SRAT: Hotplug area too small\n");
188 /* This check might be a bit too strict, but I'm keeping it for now. */
189 if (absent_pages_in_range(s_pfn
, e_pfn
) != e_pfn
- s_pfn
) {
191 "SRAT: Hotplug area %lu -> %lu has existing memory\n",
196 if (!hotadd_enough_memory(&nodes_add
[node
])) {
197 printk(KERN_ERR
"SRAT: Hotplug area too large\n");
203 if (nd
->start
== nd
->end
) {
208 if (nd
->start
== end
) {
212 if (nd
->end
== start
) {
217 printk(KERN_ERR
"SRAT: Hotplug zone not continuous. Partly ignored\n");
220 ret
= update_end_of_memory(nd
->end
);
223 printk(KERN_INFO
"SRAT: hot plug zone found %Lx - %Lx\n", nd
->start
, nd
->end
);
227 /* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
229 acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity
*ma
)
231 struct bootnode
*nd
, oldnode
;
232 unsigned long start
, end
;
238 if (ma
->header
.length
!= sizeof(struct acpi_srat_mem_affinity
)) {
242 if ((ma
->flags
& ACPI_SRAT_MEM_ENABLED
) == 0)
245 if ((ma
->flags
& ACPI_SRAT_MEM_HOT_PLUGGABLE
) && !save_add_info())
247 start
= ma
->base_address
;
248 end
= start
+ ma
->length
;
249 pxm
= ma
->proximity_domain
;
250 node
= setup_node(pxm
);
252 printk(KERN_ERR
"SRAT: Too many proximity domains.\n");
256 i
= conflicting_nodes(start
, end
);
259 "SRAT: Warning: PXM %d (%lx-%lx) overlaps with itself (%Lx-%Lx)\n",
260 pxm
, start
, end
, nodes
[i
].start
, nodes
[i
].end
);
263 "SRAT: PXM %d (%lx-%lx) overlaps with PXM %d (%Lx-%Lx)\n",
264 pxm
, start
, end
, node_to_pxm(i
),
265 nodes
[i
].start
, nodes
[i
].end
);
271 if (!node_test_and_set(node
, nodes_parsed
)) {
275 if (start
< nd
->start
)
281 printk(KERN_INFO
"SRAT: Node %u PXM %u %Lx-%Lx\n", node
, pxm
,
283 e820_register_active_regions(node
, nd
->start
>> PAGE_SHIFT
,
284 nd
->end
>> PAGE_SHIFT
);
285 push_node_boundaries(node
, nd
->start
>> PAGE_SHIFT
,
286 nd
->end
>> PAGE_SHIFT
);
288 if ((ma
->flags
& ACPI_SRAT_MEM_HOT_PLUGGABLE
) &&
289 (reserve_hotadd(node
, start
, end
) < 0)) {
290 /* Ignore hotadd region. Undo damage */
291 printk(KERN_NOTICE
"SRAT: Hotplug region ignored\n");
293 if ((nd
->start
| nd
->end
) == 0)
294 node_clear(node
, nodes_parsed
);
298 /* Sanity check to catch more bad SRATs (they are amazingly common).
299 Make sure the PXMs cover all memory. */
300 static int __init
nodes_cover_memory(const struct bootnode
*nodes
)
303 unsigned long pxmram
, e820ram
;
306 for_each_node_mask(i
, nodes_parsed
) {
307 unsigned long s
= nodes
[i
].start
>> PAGE_SHIFT
;
308 unsigned long e
= nodes
[i
].end
>> PAGE_SHIFT
;
310 pxmram
-= absent_pages_in_range(s
, e
);
311 if ((long)pxmram
< 0)
315 e820ram
= end_pfn
- absent_pages_in_range(0, end_pfn
);
316 /* We seem to lose 3 pages somewhere. Allow a bit of slack. */
317 if ((long)(e820ram
- pxmram
) >= 1*1024*1024) {
319 "SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n",
320 (pxmram
<< PAGE_SHIFT
) >> 20,
321 (e820ram
<< PAGE_SHIFT
) >> 20);
327 static void __init
unparse_node(int node
)
330 node_clear(node
, nodes_parsed
);
331 for (i
= 0; i
< MAX_LOCAL_APIC
; i
++) {
332 if (apicid_to_node
[i
] == node
)
333 apicid_to_node
[i
] = NUMA_NO_NODE
;
337 void __init
acpi_numa_arch_fixup(void) {}
339 /* Use the information discovered above to actually set up the nodes. */
340 int __init
acpi_scan_nodes(unsigned long start
, unsigned long end
)
347 /* First clean up the node list */
348 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
349 cutoff_node(i
, start
, end
);
351 * don't confuse VM with a node that doesn't have the
355 (nodes
[i
].end
- nodes
[i
].start
) < NODE_MIN_SIZE
) {
361 if (!nodes_cover_memory(nodes
)) {
366 memnode_shift
= compute_hash_shift(nodes
, MAX_NUMNODES
);
367 if (memnode_shift
< 0) {
369 "SRAT: No NUMA node hash function found. Contact maintainer\n");
374 node_possible_map
= nodes_parsed
;
376 /* Finally register nodes */
377 for_each_node_mask(i
, node_possible_map
)
378 setup_node_bootmem(i
, nodes
[i
].start
, nodes
[i
].end
);
379 /* Try again in case setup_node_bootmem missed one due
380 to missing bootmem */
381 for_each_node_mask(i
, node_possible_map
)
383 setup_node_bootmem(i
, nodes
[i
].start
, nodes
[i
].end
);
385 for (i
= 0; i
< NR_CPUS
; i
++) {
386 int node
= early_cpu_to_node(i
);
388 if (node
== NUMA_NO_NODE
)
390 if (!node_isset(node
, node_possible_map
))
391 numa_set_node(i
, NUMA_NO_NODE
);
397 #ifdef CONFIG_NUMA_EMU
398 static int fake_node_to_pxm_map
[MAX_NUMNODES
] __initdata
= {
399 [0 ... MAX_NUMNODES
-1] = PXM_INVAL
401 static s16 fake_apicid_to_node
[MAX_LOCAL_APIC
] __initdata
= {
402 [0 ... MAX_LOCAL_APIC
-1] = NUMA_NO_NODE
404 static int __init
find_node_by_addr(unsigned long addr
)
406 int ret
= NUMA_NO_NODE
;
409 for_each_node_mask(i
, nodes_parsed
) {
411 * Find the real node that this emulated node appears on. For
412 * the sake of simplicity, we only use a real node's starting
413 * address to determine which emulated node it appears on.
415 if (addr
>= nodes
[i
].start
&& addr
< nodes
[i
].end
) {
424 * In NUMA emulation, we need to setup proximity domain (_PXM) to node ID
425 * mappings that respect the real ACPI topology but reflect our emulated
426 * environment. For each emulated node, we find which real node it appears on
427 * and create PXM to NID mappings for those fake nodes which mirror that
428 * locality. SLIT will now represent the correct distances between emulated
429 * nodes as a result of the real topology.
431 void __init
acpi_fake_nodes(const struct bootnode
*fake_nodes
, int num_nodes
)
435 printk(KERN_INFO
"Faking PXM affinity for fake nodes on real "
437 for (i
= 0; i
< num_nodes
; i
++) {
440 nid
= find_node_by_addr(fake_nodes
[i
].start
);
441 if (nid
== NUMA_NO_NODE
)
443 pxm
= node_to_pxm(nid
);
444 if (pxm
== PXM_INVAL
)
446 fake_node_to_pxm_map
[i
] = pxm
;
448 * For each apicid_to_node mapping that exists for this real
449 * node, it must now point to the fake node ID.
451 for (j
= 0; j
< MAX_LOCAL_APIC
; j
++)
452 if (apicid_to_node
[j
] == nid
)
453 fake_apicid_to_node
[j
] = i
;
455 for (i
= 0; i
< num_nodes
; i
++)
456 __acpi_map_pxm_to_node(fake_node_to_pxm_map
[i
], i
);
457 memcpy(apicid_to_node
, fake_apicid_to_node
, sizeof(apicid_to_node
));
459 nodes_clear(nodes_parsed
);
460 for (i
= 0; i
< num_nodes
; i
++)
461 if (fake_nodes
[i
].start
!= fake_nodes
[i
].end
)
462 node_set(i
, nodes_parsed
);
463 WARN_ON(!nodes_cover_memory(fake_nodes
));
466 static int null_slit_node_compare(int a
, int b
)
468 return node_to_pxm(a
) == node_to_pxm(b
);
471 static int null_slit_node_compare(int a
, int b
)
475 #endif /* CONFIG_NUMA_EMU */
477 void __init
srat_reserve_add_area(int nodeid
)
479 if (found_add_area
&& nodes_add
[nodeid
].end
) {
482 printk(KERN_INFO
"SRAT: Reserving hot-add memory space "
483 "for node %d at %Lx-%Lx\n",
484 nodeid
, nodes_add
[nodeid
].start
, nodes_add
[nodeid
].end
);
485 total_mb
= (nodes_add
[nodeid
].end
- nodes_add
[nodeid
].start
)
487 total_mb
*= sizeof(struct page
);
489 printk(KERN_INFO
"SRAT: This will cost you %Lu MB of "
490 "pre-allocated memory.\n", (unsigned long long)total_mb
);
491 reserve_bootmem_node(NODE_DATA(nodeid
), nodes_add
[nodeid
].start
,
492 nodes_add
[nodeid
].end
- nodes_add
[nodeid
].start
,
497 int __node_distance(int a
, int b
)
502 return null_slit_node_compare(a
, b
) ? LOCAL_DISTANCE
:
504 index
= acpi_slit
->locality_count
* node_to_pxm(a
);
505 return acpi_slit
->entry
[index
+ node_to_pxm(b
)];
508 EXPORT_SYMBOL(__node_distance
);
510 int memory_add_physaddr_to_nid(u64 start
)
515 if (nodes_add
[i
].start
<= start
&& nodes_add
[i
].end
> start
)
520 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid
);