4 * Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
11 #define pr_fmt(fmt) "numa: " fmt
13 #include <linux/threads.h>
14 #include <linux/bootmem.h>
15 #include <linux/init.h>
17 #include <linux/mmzone.h>
18 #include <linux/export.h>
19 #include <linux/nodemask.h>
20 #include <linux/cpu.h>
21 #include <linux/notifier.h>
22 #include <linux/memblock.h>
24 #include <linux/pfn.h>
25 #include <linux/cpuset.h>
26 #include <linux/node.h>
27 #include <linux/stop_machine.h>
28 #include <linux/proc_fs.h>
29 #include <linux/seq_file.h>
30 #include <linux/uaccess.h>
31 #include <linux/slab.h>
32 #include <asm/cputhreads.h>
33 #include <asm/sparsemem.h>
36 #include <asm/cputhreads.h>
37 #include <asm/topology.h>
38 #include <asm/firmware.h>
40 #include <asm/hvcall.h>
41 #include <asm/setup.h>
44 static int numa_enabled
= 1;
46 static char *cmdline __initdata
;
48 static int numa_debug
;
49 #define dbg(args...) if (numa_debug) { printk(KERN_INFO args); }
51 int numa_cpu_lookup_table
[NR_CPUS
];
52 cpumask_var_t node_to_cpumask_map
[MAX_NUMNODES
];
53 struct pglist_data
*node_data
[MAX_NUMNODES
];
55 EXPORT_SYMBOL(numa_cpu_lookup_table
);
56 EXPORT_SYMBOL(node_to_cpumask_map
);
57 EXPORT_SYMBOL(node_data
);
59 static int min_common_depth
;
60 static int n_mem_addr_cells
, n_mem_size_cells
;
61 static int form1_affinity
;
63 #define MAX_DISTANCE_REF_POINTS 4
64 static int distance_ref_points_depth
;
65 static const __be32
*distance_ref_points
;
66 static int distance_lookup_table
[MAX_NUMNODES
][MAX_DISTANCE_REF_POINTS
];
69 * Allocate node_to_cpumask_map based on number of available nodes
70 * Requires node_possible_map to be valid.
72 * Note: cpumask_of_node() is not valid until after this is done.
74 static void __init
setup_node_to_cpumask_map(void)
78 /* setup nr_node_ids if not done yet */
79 if (nr_node_ids
== MAX_NUMNODES
)
82 /* allocate the map */
83 for (node
= 0; node
< nr_node_ids
; node
++)
84 alloc_bootmem_cpumask_var(&node_to_cpumask_map
[node
]);
86 /* cpumask_of_node() will now work */
87 dbg("Node to cpumask map for %d nodes\n", nr_node_ids
);
90 static int __init
fake_numa_create_new_node(unsigned long end_pfn
,
93 unsigned long long mem
;
95 static unsigned int fake_nid
;
96 static unsigned long long curr_boundary
;
99 * Modify node id, iff we started creating NUMA nodes
100 * We want to continue from where we left of the last time
105 * In case there are no more arguments to parse, the
106 * node_id should be the same as the last fake node id
107 * (we've handled this above).
112 mem
= memparse(p
, &p
);
116 if (mem
< curr_boundary
)
121 if ((end_pfn
<< PAGE_SHIFT
) > mem
) {
123 * Skip commas and spaces
125 while (*p
== ',' || *p
== ' ' || *p
== '\t')
131 dbg("created new fake_node with id %d\n", fake_nid
);
138 * get_node_active_region - Return active region containing pfn
139 * Active range returned is empty if none found.
140 * @pfn: The page to return the region for
141 * @node_ar: Returned set to the active region containing @pfn
143 static void __init
get_node_active_region(unsigned long pfn
,
144 struct node_active_region
*node_ar
)
146 unsigned long start_pfn
, end_pfn
;
149 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start_pfn
, &end_pfn
, &nid
) {
150 if (pfn
>= start_pfn
&& pfn
< end_pfn
) {
152 node_ar
->start_pfn
= start_pfn
;
153 node_ar
->end_pfn
= end_pfn
;
159 static void reset_numa_cpu_lookup_table(void)
163 for_each_possible_cpu(cpu
)
164 numa_cpu_lookup_table
[cpu
] = -1;
167 static void update_numa_cpu_lookup_table(unsigned int cpu
, int node
)
169 numa_cpu_lookup_table
[cpu
] = node
;
172 static void map_cpu_to_node(int cpu
, int node
)
174 update_numa_cpu_lookup_table(cpu
, node
);
176 dbg("adding cpu %d to node %d\n", cpu
, node
);
178 if (!(cpumask_test_cpu(cpu
, node_to_cpumask_map
[node
])))
179 cpumask_set_cpu(cpu
, node_to_cpumask_map
[node
]);
182 #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PPC_SPLPAR)
183 static void unmap_cpu_from_node(unsigned long cpu
)
185 int node
= numa_cpu_lookup_table
[cpu
];
187 dbg("removing cpu %lu from node %d\n", cpu
, node
);
189 if (cpumask_test_cpu(cpu
, node_to_cpumask_map
[node
])) {
190 cpumask_clear_cpu(cpu
, node_to_cpumask_map
[node
]);
192 printk(KERN_ERR
"WARNING: cpu %lu not found in node %d\n",
196 #endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */
198 /* must hold reference to node during call */
199 static const __be32
*of_get_associativity(struct device_node
*dev
)
201 return of_get_property(dev
, "ibm,associativity", NULL
);
205 * Returns the property linux,drconf-usable-memory if
206 * it exists (the property exists only in kexec/kdump kernels,
207 * added by kexec-tools)
209 static const __be32
*of_get_usable_memory(struct device_node
*memory
)
213 prop
= of_get_property(memory
, "linux,drconf-usable-memory", &len
);
214 if (!prop
|| len
< sizeof(unsigned int))
219 int __node_distance(int a
, int b
)
222 int distance
= LOCAL_DISTANCE
;
225 return ((a
== b
) ? LOCAL_DISTANCE
: REMOTE_DISTANCE
);
227 for (i
= 0; i
< distance_ref_points_depth
; i
++) {
228 if (distance_lookup_table
[a
][i
] == distance_lookup_table
[b
][i
])
231 /* Double the distance for each NUMA level */
237 EXPORT_SYMBOL(__node_distance
);
239 static void initialize_distance_lookup_table(int nid
,
240 const __be32
*associativity
)
247 for (i
= 0; i
< distance_ref_points_depth
; i
++) {
250 entry
= &associativity
[be32_to_cpu(distance_ref_points
[i
])];
251 distance_lookup_table
[nid
][i
] = of_read_number(entry
, 1);
255 /* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
258 static int associativity_to_nid(const __be32
*associativity
)
262 if (min_common_depth
== -1)
265 if (of_read_number(associativity
, 1) >= min_common_depth
)
266 nid
= of_read_number(&associativity
[min_common_depth
], 1);
268 /* POWER4 LPAR uses 0xffff as invalid node */
269 if (nid
== 0xffff || nid
>= MAX_NUMNODES
)
273 of_read_number(associativity
, 1) >= distance_ref_points_depth
)
274 initialize_distance_lookup_table(nid
, associativity
);
280 /* Returns the nid associated with the given device tree node,
281 * or -1 if not found.
283 static int of_node_to_nid_single(struct device_node
*device
)
288 tmp
= of_get_associativity(device
);
290 nid
= associativity_to_nid(tmp
);
294 /* Walk the device tree upwards, looking for an associativity id */
295 int of_node_to_nid(struct device_node
*device
)
297 struct device_node
*tmp
;
302 nid
= of_node_to_nid_single(device
);
307 device
= of_get_parent(tmp
);
314 EXPORT_SYMBOL_GPL(of_node_to_nid
);
316 static int __init
find_min_common_depth(void)
319 struct device_node
*root
;
321 if (firmware_has_feature(FW_FEATURE_OPAL
))
322 root
= of_find_node_by_path("/ibm,opal");
324 root
= of_find_node_by_path("/rtas");
326 root
= of_find_node_by_path("/");
329 * This property is a set of 32-bit integers, each representing
330 * an index into the ibm,associativity nodes.
332 * With form 0 affinity the first integer is for an SMP configuration
333 * (should be all 0's) and the second is for a normal NUMA
334 * configuration. We have only one level of NUMA.
336 * With form 1 affinity the first integer is the most significant
337 * NUMA boundary and the following are progressively less significant
338 * boundaries. There can be more than one level of NUMA.
340 distance_ref_points
= of_get_property(root
,
341 "ibm,associativity-reference-points",
342 &distance_ref_points_depth
);
344 if (!distance_ref_points
) {
345 dbg("NUMA: ibm,associativity-reference-points not found.\n");
349 distance_ref_points_depth
/= sizeof(int);
351 if (firmware_has_feature(FW_FEATURE_OPAL
) ||
352 firmware_has_feature(FW_FEATURE_TYPE1_AFFINITY
)) {
353 dbg("Using form 1 affinity\n");
357 if (form1_affinity
) {
358 depth
= of_read_number(distance_ref_points
, 1);
360 if (distance_ref_points_depth
< 2) {
361 printk(KERN_WARNING
"NUMA: "
362 "short ibm,associativity-reference-points\n");
366 depth
= of_read_number(&distance_ref_points
[1], 1);
370 * Warn and cap if the hardware supports more than
371 * MAX_DISTANCE_REF_POINTS domains.
373 if (distance_ref_points_depth
> MAX_DISTANCE_REF_POINTS
) {
374 printk(KERN_WARNING
"NUMA: distance array capped at "
375 "%d entries\n", MAX_DISTANCE_REF_POINTS
);
376 distance_ref_points_depth
= MAX_DISTANCE_REF_POINTS
;
387 static void __init
get_n_mem_cells(int *n_addr_cells
, int *n_size_cells
)
389 struct device_node
*memory
= NULL
;
391 memory
= of_find_node_by_type(memory
, "memory");
393 panic("numa.c: No memory nodes found!");
395 *n_addr_cells
= of_n_addr_cells(memory
);
396 *n_size_cells
= of_n_size_cells(memory
);
400 static unsigned long read_n_cells(int n
, const __be32
**buf
)
402 unsigned long result
= 0;
405 result
= (result
<< 32) | of_read_number(*buf
, 1);
412 * Read the next memblock list entry from the ibm,dynamic-memory property
413 * and return the information in the provided of_drconf_cell structure.
415 static void read_drconf_cell(struct of_drconf_cell
*drmem
, const __be32
**cellp
)
419 drmem
->base_addr
= read_n_cells(n_mem_addr_cells
, cellp
);
422 drmem
->drc_index
= of_read_number(cp
, 1);
423 drmem
->reserved
= of_read_number(&cp
[1], 1);
424 drmem
->aa_index
= of_read_number(&cp
[2], 1);
425 drmem
->flags
= of_read_number(&cp
[3], 1);
431 * Retrieve and validate the ibm,dynamic-memory property of the device tree.
433 * The layout of the ibm,dynamic-memory property is a number N of memblock
434 * list entries followed by N memblock list entries. Each memblock list entry
435 * contains information as laid out in the of_drconf_cell struct above.
437 static int of_get_drconf_memory(struct device_node
*memory
, const __be32
**dm
)
442 prop
= of_get_property(memory
, "ibm,dynamic-memory", &len
);
443 if (!prop
|| len
< sizeof(unsigned int))
446 entries
= of_read_number(prop
++, 1);
448 /* Now that we know the number of entries, revalidate the size
449 * of the property read in to ensure we have everything
451 if (len
< (entries
* (n_mem_addr_cells
+ 4) + 1) * sizeof(unsigned int))
459 * Retrieve and validate the ibm,lmb-size property for drconf memory
460 * from the device tree.
462 static u64
of_get_lmb_size(struct device_node
*memory
)
467 prop
= of_get_property(memory
, "ibm,lmb-size", &len
);
468 if (!prop
|| len
< sizeof(unsigned int))
471 return read_n_cells(n_mem_size_cells
, &prop
);
474 struct assoc_arrays
{
477 const __be32
*arrays
;
481 * Retrieve and validate the list of associativity arrays for drconf
482 * memory from the ibm,associativity-lookup-arrays property of the
485 * The layout of the ibm,associativity-lookup-arrays property is a number N
486 * indicating the number of associativity arrays, followed by a number M
487 * indicating the size of each associativity array, followed by a list
488 * of N associativity arrays.
490 static int of_get_assoc_arrays(struct device_node
*memory
,
491 struct assoc_arrays
*aa
)
496 prop
= of_get_property(memory
, "ibm,associativity-lookup-arrays", &len
);
497 if (!prop
|| len
< 2 * sizeof(unsigned int))
500 aa
->n_arrays
= of_read_number(prop
++, 1);
501 aa
->array_sz
= of_read_number(prop
++, 1);
503 /* Now that we know the number of arrays and size of each array,
504 * revalidate the size of the property read in.
506 if (len
< (aa
->n_arrays
* aa
->array_sz
+ 2) * sizeof(unsigned int))
514 * This is like of_node_to_nid_single() for memory represented in the
515 * ibm,dynamic-reconfiguration-memory node.
517 static int of_drconf_to_nid_single(struct of_drconf_cell
*drmem
,
518 struct assoc_arrays
*aa
)
521 int nid
= default_nid
;
524 if (min_common_depth
> 0 && min_common_depth
<= aa
->array_sz
&&
525 !(drmem
->flags
& DRCONF_MEM_AI_INVALID
) &&
526 drmem
->aa_index
< aa
->n_arrays
) {
527 index
= drmem
->aa_index
* aa
->array_sz
+ min_common_depth
- 1;
528 nid
= of_read_number(&aa
->arrays
[index
], 1);
530 if (nid
== 0xffff || nid
>= MAX_NUMNODES
)
538 * Figure out to which domain a cpu belongs and stick it there.
539 * Return the id of the domain used.
541 static int numa_setup_cpu(unsigned long lcpu
)
544 struct device_node
*cpu
;
547 * If a valid cpu-to-node mapping is already available, use it
548 * directly instead of querying the firmware, since it represents
549 * the most recent mapping notified to us by the platform (eg: VPHN).
551 if ((nid
= numa_cpu_lookup_table
[lcpu
]) >= 0) {
552 map_cpu_to_node(lcpu
, nid
);
556 cpu
= of_get_cpu_node(lcpu
, NULL
);
560 if (cpu_present(lcpu
))
566 nid
= of_node_to_nid_single(cpu
);
569 if (nid
< 0 || !node_online(nid
))
570 nid
= first_online_node
;
572 map_cpu_to_node(lcpu
, nid
);
578 static void verify_cpu_node_mapping(int cpu
, int node
)
580 int base
, sibling
, i
;
582 /* Verify that all the threads in the core belong to the same node */
583 base
= cpu_first_thread_sibling(cpu
);
585 for (i
= 0; i
< threads_per_core
; i
++) {
588 if (sibling
== cpu
|| cpu_is_offline(sibling
))
591 if (cpu_to_node(sibling
) != node
) {
592 WARN(1, "CPU thread siblings %d and %d don't belong"
593 " to the same node!\n", cpu
, sibling
);
599 static int cpu_numa_callback(struct notifier_block
*nfb
, unsigned long action
,
602 unsigned long lcpu
= (unsigned long)hcpu
;
603 int ret
= NOTIFY_DONE
, nid
;
607 case CPU_UP_PREPARE_FROZEN
:
608 nid
= numa_setup_cpu(lcpu
);
609 verify_cpu_node_mapping((int)lcpu
, nid
);
612 #ifdef CONFIG_HOTPLUG_CPU
614 case CPU_DEAD_FROZEN
:
615 case CPU_UP_CANCELED
:
616 case CPU_UP_CANCELED_FROZEN
:
617 unmap_cpu_from_node(lcpu
);
626 * Check and possibly modify a memory region to enforce the memory limit.
628 * Returns the size the region should have to enforce the memory limit.
629 * This will either be the original value of size, a truncated value,
630 * or zero. If the returned value of size is 0 the region should be
631 * discarded as it lies wholly above the memory limit.
633 static unsigned long __init
numa_enforce_memory_limit(unsigned long start
,
637 * We use memblock_end_of_DRAM() in here instead of memory_limit because
638 * we've already adjusted it for the limit and it takes care of
639 * having memory holes below the limit. Also, in the case of
640 * iommu_is_off, memory_limit is not set but is implicitly enforced.
643 if (start
+ size
<= memblock_end_of_DRAM())
646 if (start
>= memblock_end_of_DRAM())
649 return memblock_end_of_DRAM() - start
;
653 * Reads the counter for a given entry in
654 * linux,drconf-usable-memory property
656 static inline int __init
read_usm_ranges(const __be32
**usm
)
659 * For each lmb in ibm,dynamic-memory a corresponding
660 * entry in linux,drconf-usable-memory property contains
661 * a counter followed by that many (base, size) duple.
662 * read the counter from linux,drconf-usable-memory
664 return read_n_cells(n_mem_size_cells
, usm
);
668 * Extract NUMA information from the ibm,dynamic-reconfiguration-memory
669 * node. This assumes n_mem_{addr,size}_cells have been set.
671 static void __init
parse_drconf_memory(struct device_node
*memory
)
673 const __be32
*uninitialized_var(dm
), *usm
;
674 unsigned int n
, rc
, ranges
, is_kexec_kdump
= 0;
675 unsigned long lmb_size
, base
, size
, sz
;
677 struct assoc_arrays aa
= { .arrays
= NULL
};
679 n
= of_get_drconf_memory(memory
, &dm
);
683 lmb_size
= of_get_lmb_size(memory
);
687 rc
= of_get_assoc_arrays(memory
, &aa
);
691 /* check if this is a kexec/kdump kernel */
692 usm
= of_get_usable_memory(memory
);
696 for (; n
!= 0; --n
) {
697 struct of_drconf_cell drmem
;
699 read_drconf_cell(&drmem
, &dm
);
701 /* skip this block if the reserved bit is set in flags (0x80)
702 or if the block is not assigned to this partition (0x8) */
703 if ((drmem
.flags
& DRCONF_MEM_RESERVED
)
704 || !(drmem
.flags
& DRCONF_MEM_ASSIGNED
))
707 base
= drmem
.base_addr
;
711 if (is_kexec_kdump
) {
712 ranges
= read_usm_ranges(&usm
);
713 if (!ranges
) /* there are no (base, size) duple */
717 if (is_kexec_kdump
) {
718 base
= read_n_cells(n_mem_addr_cells
, &usm
);
719 size
= read_n_cells(n_mem_size_cells
, &usm
);
721 nid
= of_drconf_to_nid_single(&drmem
, &aa
);
722 fake_numa_create_new_node(
723 ((base
+ size
) >> PAGE_SHIFT
),
725 node_set_online(nid
);
726 sz
= numa_enforce_memory_limit(base
, size
);
728 memblock_set_node(base
, sz
,
729 &memblock
.memory
, nid
);
734 static int __init
parse_numa_properties(void)
736 struct device_node
*memory
;
740 if (numa_enabled
== 0) {
741 printk(KERN_WARNING
"NUMA disabled by user\n");
745 min_common_depth
= find_min_common_depth();
747 if (min_common_depth
< 0)
748 return min_common_depth
;
750 dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth
);
753 * Even though we connect cpus to numa domains later in SMP
754 * init, we need to know the node ids now. This is because
755 * each node to be onlined must have NODE_DATA etc backing it.
757 for_each_present_cpu(i
) {
758 struct device_node
*cpu
;
761 cpu
= of_get_cpu_node(i
, NULL
);
763 nid
= of_node_to_nid_single(cpu
);
767 * Don't fall back to default_nid yet -- we will plug
768 * cpus into nodes once the memory scan has discovered
773 node_set_online(nid
);
776 get_n_mem_cells(&n_mem_addr_cells
, &n_mem_size_cells
);
778 for_each_node_by_type(memory
, "memory") {
783 const __be32
*memcell_buf
;
786 memcell_buf
= of_get_property(memory
,
787 "linux,usable-memory", &len
);
788 if (!memcell_buf
|| len
<= 0)
789 memcell_buf
= of_get_property(memory
, "reg", &len
);
790 if (!memcell_buf
|| len
<= 0)
794 ranges
= (len
>> 2) / (n_mem_addr_cells
+ n_mem_size_cells
);
796 /* these are order-sensitive, and modify the buffer pointer */
797 start
= read_n_cells(n_mem_addr_cells
, &memcell_buf
);
798 size
= read_n_cells(n_mem_size_cells
, &memcell_buf
);
801 * Assumption: either all memory nodes or none will
802 * have associativity properties. If none, then
803 * everything goes to default_nid.
805 nid
= of_node_to_nid_single(memory
);
809 fake_numa_create_new_node(((start
+ size
) >> PAGE_SHIFT
), &nid
);
810 node_set_online(nid
);
812 if (!(size
= numa_enforce_memory_limit(start
, size
))) {
819 memblock_set_node(start
, size
, &memblock
.memory
, nid
);
826 * Now do the same thing for each MEMBLOCK listed in the
827 * ibm,dynamic-memory property in the
828 * ibm,dynamic-reconfiguration-memory node.
830 memory
= of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
832 parse_drconf_memory(memory
);
837 static void __init
setup_nonnuma(void)
839 unsigned long top_of_ram
= memblock_end_of_DRAM();
840 unsigned long total_ram
= memblock_phys_mem_size();
841 unsigned long start_pfn
, end_pfn
;
842 unsigned int nid
= 0;
843 struct memblock_region
*reg
;
845 printk(KERN_DEBUG
"Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
846 top_of_ram
, total_ram
);
847 printk(KERN_DEBUG
"Memory hole size: %ldMB\n",
848 (top_of_ram
- total_ram
) >> 20);
850 for_each_memblock(memory
, reg
) {
851 start_pfn
= memblock_region_memory_base_pfn(reg
);
852 end_pfn
= memblock_region_memory_end_pfn(reg
);
854 fake_numa_create_new_node(end_pfn
, &nid
);
855 memblock_set_node(PFN_PHYS(start_pfn
),
856 PFN_PHYS(end_pfn
- start_pfn
),
857 &memblock
.memory
, nid
);
858 node_set_online(nid
);
862 void __init
dump_numa_cpu_topology(void)
865 unsigned int cpu
, count
;
867 if (min_common_depth
== -1 || !numa_enabled
)
870 for_each_online_node(node
) {
871 printk(KERN_DEBUG
"Node %d CPUs:", node
);
875 * If we used a CPU iterator here we would miss printing
876 * the holes in the cpumap.
878 for (cpu
= 0; cpu
< nr_cpu_ids
; cpu
++) {
879 if (cpumask_test_cpu(cpu
,
880 node_to_cpumask_map
[node
])) {
886 printk("-%u", cpu
- 1);
892 printk("-%u", nr_cpu_ids
- 1);
897 static void __init
dump_numa_memory_topology(void)
902 if (min_common_depth
== -1 || !numa_enabled
)
905 for_each_online_node(node
) {
908 printk(KERN_DEBUG
"Node %d Memory:", node
);
912 for (i
= 0; i
< memblock_end_of_DRAM();
913 i
+= (1 << SECTION_SIZE_BITS
)) {
914 if (early_pfn_to_nid(i
>> PAGE_SHIFT
) == node
) {
932 * Allocate some memory, satisfying the memblock or bootmem allocator where
933 * required. nid is the preferred node and end is the physical address of
934 * the highest address in the node.
936 * Returns the virtual address of the memory.
938 static void __init
*careful_zallocation(int nid
, unsigned long size
,
940 unsigned long end_pfn
)
944 unsigned long ret_paddr
;
946 ret_paddr
= __memblock_alloc_base(size
, align
, end_pfn
<< PAGE_SHIFT
);
948 /* retry over all memory */
950 ret_paddr
= __memblock_alloc_base(size
, align
, memblock_end_of_DRAM());
953 panic("numa.c: cannot allocate %lu bytes for node %d",
956 ret
= __va(ret_paddr
);
959 * We initialize the nodes in numeric order: 0, 1, 2...
960 * and hand over control from the MEMBLOCK allocator to the
961 * bootmem allocator. If this function is called for
962 * node 5, then we know that all nodes <5 are using the
963 * bootmem allocator instead of the MEMBLOCK allocator.
965 * So, check the nid from which this allocation came
966 * and double check to see if we need to use bootmem
967 * instead of the MEMBLOCK. We don't free the MEMBLOCK memory
968 * since it would be useless.
970 new_nid
= early_pfn_to_nid(ret_paddr
>> PAGE_SHIFT
);
972 ret
= __alloc_bootmem_node(NODE_DATA(new_nid
),
975 dbg("alloc_bootmem %p %lx\n", ret
, size
);
978 memset(ret
, 0, size
);
982 static struct notifier_block ppc64_numa_nb
= {
983 .notifier_call
= cpu_numa_callback
,
984 .priority
= 1 /* Must run before sched domains notifier. */
987 static void __init
mark_reserved_regions_for_nid(int nid
)
989 struct pglist_data
*node
= NODE_DATA(nid
);
990 struct memblock_region
*reg
;
992 for_each_memblock(reserved
, reg
) {
993 unsigned long physbase
= reg
->base
;
994 unsigned long size
= reg
->size
;
995 unsigned long start_pfn
= physbase
>> PAGE_SHIFT
;
996 unsigned long end_pfn
= PFN_UP(physbase
+ size
);
997 struct node_active_region node_ar
;
998 unsigned long node_end_pfn
= pgdat_end_pfn(node
);
1001 * Check to make sure that this memblock.reserved area is
1002 * within the bounds of the node that we care about.
1003 * Checking the nid of the start and end points is not
1004 * sufficient because the reserved area could span the
1007 if (end_pfn
<= node
->node_start_pfn
||
1008 start_pfn
>= node_end_pfn
)
1011 get_node_active_region(start_pfn
, &node_ar
);
1012 while (start_pfn
< end_pfn
&&
1013 node_ar
.start_pfn
< node_ar
.end_pfn
) {
1014 unsigned long reserve_size
= size
;
1016 * if reserved region extends past active region
1017 * then trim size to active region
1019 if (end_pfn
> node_ar
.end_pfn
)
1020 reserve_size
= (node_ar
.end_pfn
<< PAGE_SHIFT
)
1023 * Only worry about *this* node, others may not
1024 * yet have valid NODE_DATA().
1026 if (node_ar
.nid
== nid
) {
1027 dbg("reserve_bootmem %lx %lx nid=%d\n",
1028 physbase
, reserve_size
, node_ar
.nid
);
1029 reserve_bootmem_node(NODE_DATA(node_ar
.nid
),
1030 physbase
, reserve_size
,
1034 * if reserved region is contained in the active region
1037 if (end_pfn
<= node_ar
.end_pfn
)
1041 * reserved region extends past the active region
1042 * get next active region that contains this
1045 start_pfn
= node_ar
.end_pfn
;
1046 physbase
= start_pfn
<< PAGE_SHIFT
;
1047 size
= size
- reserve_size
;
1048 get_node_active_region(start_pfn
, &node_ar
);
1054 void __init
do_init_bootmem(void)
1059 max_low_pfn
= memblock_end_of_DRAM() >> PAGE_SHIFT
;
1060 max_pfn
= max_low_pfn
;
1062 if (parse_numa_properties())
1065 dump_numa_memory_topology();
1067 for_each_online_node(nid
) {
1068 unsigned long start_pfn
, end_pfn
;
1069 void *bootmem_vaddr
;
1070 unsigned long bootmap_pages
;
1072 get_pfn_range_for_nid(nid
, &start_pfn
, &end_pfn
);
1075 * Allocate the node structure node local if possible
1077 * Be careful moving this around, as it relies on all
1078 * previous nodes' bootmem to be initialized and have
1079 * all reserved areas marked.
1081 NODE_DATA(nid
) = careful_zallocation(nid
,
1082 sizeof(struct pglist_data
),
1083 SMP_CACHE_BYTES
, end_pfn
);
1085 dbg("node %d\n", nid
);
1086 dbg("NODE_DATA() = %p\n", NODE_DATA(nid
));
1088 NODE_DATA(nid
)->bdata
= &bootmem_node_data
[nid
];
1089 NODE_DATA(nid
)->node_start_pfn
= start_pfn
;
1090 NODE_DATA(nid
)->node_spanned_pages
= end_pfn
- start_pfn
;
1092 if (NODE_DATA(nid
)->node_spanned_pages
== 0)
1095 dbg("start_paddr = %lx\n", start_pfn
<< PAGE_SHIFT
);
1096 dbg("end_paddr = %lx\n", end_pfn
<< PAGE_SHIFT
);
1098 bootmap_pages
= bootmem_bootmap_pages(end_pfn
- start_pfn
);
1099 bootmem_vaddr
= careful_zallocation(nid
,
1100 bootmap_pages
<< PAGE_SHIFT
,
1101 PAGE_SIZE
, end_pfn
);
1103 dbg("bootmap_vaddr = %p\n", bootmem_vaddr
);
1105 init_bootmem_node(NODE_DATA(nid
),
1106 __pa(bootmem_vaddr
) >> PAGE_SHIFT
,
1107 start_pfn
, end_pfn
);
1109 free_bootmem_with_active_regions(nid
, end_pfn
);
1111 * Be very careful about moving this around. Future
1112 * calls to careful_zallocation() depend on this getting
1115 mark_reserved_regions_for_nid(nid
);
1116 sparse_memory_present_with_active_regions(nid
);
1119 init_bootmem_done
= 1;
1122 * Now bootmem is initialised we can create the node to cpumask
1123 * lookup tables and setup the cpu callback to populate them.
1125 setup_node_to_cpumask_map();
1127 reset_numa_cpu_lookup_table();
1128 register_cpu_notifier(&ppc64_numa_nb
);
1130 * We need the numa_cpu_lookup_table to be accurate for all CPUs,
1131 * even before we online them, so that we can use cpu_to_{node,mem}
1132 * early in boot, cf. smp_prepare_cpus().
1134 for_each_present_cpu(cpu
) {
1135 numa_setup_cpu((unsigned long)cpu
);
1139 static int __init
early_numa(char *p
)
1144 if (strstr(p
, "off"))
1147 if (strstr(p
, "debug"))
1150 p
= strstr(p
, "fake=");
1152 cmdline
= p
+ strlen("fake=");
1156 early_param("numa", early_numa
);
1158 static bool topology_updates_enabled
= true;
1160 static int __init
early_topology_updates(char *p
)
1165 if (!strcmp(p
, "off")) {
1166 pr_info("Disabling topology updates\n");
1167 topology_updates_enabled
= false;
1172 early_param("topology_updates", early_topology_updates
);
1174 #ifdef CONFIG_MEMORY_HOTPLUG
1176 * Find the node associated with a hot added memory section for
1177 * memory represented in the device tree by the property
1178 * ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory.
1180 static int hot_add_drconf_scn_to_nid(struct device_node
*memory
,
1181 unsigned long scn_addr
)
1184 unsigned int drconf_cell_cnt
, rc
;
1185 unsigned long lmb_size
;
1186 struct assoc_arrays aa
;
1189 drconf_cell_cnt
= of_get_drconf_memory(memory
, &dm
);
1190 if (!drconf_cell_cnt
)
1193 lmb_size
= of_get_lmb_size(memory
);
1197 rc
= of_get_assoc_arrays(memory
, &aa
);
1201 for (; drconf_cell_cnt
!= 0; --drconf_cell_cnt
) {
1202 struct of_drconf_cell drmem
;
1204 read_drconf_cell(&drmem
, &dm
);
1206 /* skip this block if it is reserved or not assigned to
1208 if ((drmem
.flags
& DRCONF_MEM_RESERVED
)
1209 || !(drmem
.flags
& DRCONF_MEM_ASSIGNED
))
1212 if ((scn_addr
< drmem
.base_addr
)
1213 || (scn_addr
>= (drmem
.base_addr
+ lmb_size
)))
1216 nid
= of_drconf_to_nid_single(&drmem
, &aa
);
1224 * Find the node associated with a hot added memory section for memory
1225 * represented in the device tree as a node (i.e. memory@XXXX) for
1228 static int hot_add_node_scn_to_nid(unsigned long scn_addr
)
1230 struct device_node
*memory
;
1233 for_each_node_by_type(memory
, "memory") {
1234 unsigned long start
, size
;
1236 const __be32
*memcell_buf
;
1239 memcell_buf
= of_get_property(memory
, "reg", &len
);
1240 if (!memcell_buf
|| len
<= 0)
1243 /* ranges in cell */
1244 ranges
= (len
>> 2) / (n_mem_addr_cells
+ n_mem_size_cells
);
1247 start
= read_n_cells(n_mem_addr_cells
, &memcell_buf
);
1248 size
= read_n_cells(n_mem_size_cells
, &memcell_buf
);
1250 if ((scn_addr
< start
) || (scn_addr
>= (start
+ size
)))
1253 nid
= of_node_to_nid_single(memory
);
1261 of_node_put(memory
);
1267 * Find the node associated with a hot added memory section. Section
1268 * corresponds to a SPARSEMEM section, not an MEMBLOCK. It is assumed that
1269 * sections are fully contained within a single MEMBLOCK.
1271 int hot_add_scn_to_nid(unsigned long scn_addr
)
1273 struct device_node
*memory
= NULL
;
1276 if (!numa_enabled
|| (min_common_depth
< 0))
1277 return first_online_node
;
1279 memory
= of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1281 nid
= hot_add_drconf_scn_to_nid(memory
, scn_addr
);
1282 of_node_put(memory
);
1284 nid
= hot_add_node_scn_to_nid(scn_addr
);
1287 if (nid
< 0 || !node_online(nid
))
1288 nid
= first_online_node
;
1290 if (NODE_DATA(nid
)->node_spanned_pages
)
1293 for_each_online_node(nid
) {
1294 if (NODE_DATA(nid
)->node_spanned_pages
) {
1304 static u64
hot_add_drconf_memory_max(void)
1306 struct device_node
*memory
= NULL
;
1307 unsigned int drconf_cell_cnt
= 0;
1309 const __be32
*dm
= NULL
;
1311 memory
= of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1313 drconf_cell_cnt
= of_get_drconf_memory(memory
, &dm
);
1314 lmb_size
= of_get_lmb_size(memory
);
1315 of_node_put(memory
);
1317 return lmb_size
* drconf_cell_cnt
;
1321 * memory_hotplug_max - return max address of memory that may be added
1323 * This is currently only used on systems that support drconfig memory
1326 u64
memory_hotplug_max(void)
1328 return max(hot_add_drconf_memory_max(), memblock_end_of_DRAM());
1330 #endif /* CONFIG_MEMORY_HOTPLUG */
1332 /* Virtual Processor Home Node (VPHN) support */
1333 #ifdef CONFIG_PPC_SPLPAR
1334 struct topology_update_data
{
1335 struct topology_update_data
*next
;
1341 static u8 vphn_cpu_change_counts
[NR_CPUS
][MAX_DISTANCE_REF_POINTS
];
1342 static cpumask_t cpu_associativity_changes_mask
;
1343 static int vphn_enabled
;
1344 static int prrn_enabled
;
1345 static void reset_topology_timer(void);
1348 * Store the current values of the associativity change counters in the
1351 static void setup_cpu_associativity_change_counters(void)
1355 /* The VPHN feature supports a maximum of 8 reference points */
1356 BUILD_BUG_ON(MAX_DISTANCE_REF_POINTS
> 8);
1358 for_each_possible_cpu(cpu
) {
1360 u8
*counts
= vphn_cpu_change_counts
[cpu
];
1361 volatile u8
*hypervisor_counts
= lppaca
[cpu
].vphn_assoc_counts
;
1363 for (i
= 0; i
< distance_ref_points_depth
; i
++)
1364 counts
[i
] = hypervisor_counts
[i
];
1369 * The hypervisor maintains a set of 8 associativity change counters in
1370 * the VPA of each cpu that correspond to the associativity levels in the
1371 * ibm,associativity-reference-points property. When an associativity
1372 * level changes, the corresponding counter is incremented.
1374 * Set a bit in cpu_associativity_changes_mask for each cpu whose home
1375 * node associativity levels have changed.
1377 * Returns the number of cpus with unhandled associativity changes.
1379 static int update_cpu_associativity_changes_mask(void)
1382 cpumask_t
*changes
= &cpu_associativity_changes_mask
;
1384 for_each_possible_cpu(cpu
) {
1386 u8
*counts
= vphn_cpu_change_counts
[cpu
];
1387 volatile u8
*hypervisor_counts
= lppaca
[cpu
].vphn_assoc_counts
;
1389 for (i
= 0; i
< distance_ref_points_depth
; i
++) {
1390 if (hypervisor_counts
[i
] != counts
[i
]) {
1391 counts
[i
] = hypervisor_counts
[i
];
1396 cpumask_or(changes
, changes
, cpu_sibling_mask(cpu
));
1397 cpu
= cpu_last_thread_sibling(cpu
);
1401 return cpumask_weight(changes
);
1405 * 6 64-bit registers unpacked into 12 32-bit associativity values. To form
1406 * the complete property we have to add the length in the first cell.
1408 #define VPHN_ASSOC_BUFSIZE (6*sizeof(u64)/sizeof(u32) + 1)
1411 * Convert the associativity domain numbers returned from the hypervisor
1412 * to the sequence they would appear in the ibm,associativity property.
1414 static int vphn_unpack_associativity(const long *packed
, __be32
*unpacked
)
1416 int i
, nr_assoc_doms
= 0;
1417 const __be16
*field
= (const __be16
*) packed
;
1419 #define VPHN_FIELD_UNUSED (0xffff)
1420 #define VPHN_FIELD_MSB (0x8000)
1421 #define VPHN_FIELD_MASK (~VPHN_FIELD_MSB)
1423 for (i
= 1; i
< VPHN_ASSOC_BUFSIZE
; i
++) {
1424 if (be16_to_cpup(field
) == VPHN_FIELD_UNUSED
) {
1425 /* All significant fields processed, and remaining
1426 * fields contain the reserved value of all 1's.
1429 unpacked
[i
] = *((__be32
*)field
);
1431 } else if (be16_to_cpup(field
) & VPHN_FIELD_MSB
) {
1432 /* Data is in the lower 15 bits of this field */
1433 unpacked
[i
] = cpu_to_be32(
1434 be16_to_cpup(field
) & VPHN_FIELD_MASK
);
1438 /* Data is in the lower 15 bits of this field
1439 * concatenated with the next 16 bit field
1441 unpacked
[i
] = *((__be32
*)field
);
1447 /* The first cell contains the length of the property */
1448 unpacked
[0] = cpu_to_be32(nr_assoc_doms
);
1450 return nr_assoc_doms
;
1454 * Retrieve the new associativity information for a virtual processor's
1457 static long hcall_vphn(unsigned long cpu
, __be32
*associativity
)
1460 long retbuf
[PLPAR_HCALL9_BUFSIZE
] = {0};
1462 int hwcpu
= get_hard_smp_processor_id(cpu
);
1465 rc
= plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY
, retbuf
, flags
, hwcpu
);
1466 for (i
= 0; i
< 6; i
++)
1467 retbuf
[i
] = cpu_to_be64(retbuf
[i
]);
1468 vphn_unpack_associativity(retbuf
, associativity
);
1473 static long vphn_get_associativity(unsigned long cpu
,
1474 __be32
*associativity
)
1478 rc
= hcall_vphn(cpu
, associativity
);
1483 "VPHN is not supported. Disabling polling...\n");
1484 stop_topology_update();
1488 "hcall_vphn() experienced a hardware fault "
1489 "preventing VPHN. Disabling polling...\n");
1490 stop_topology_update();
1497 * Update the CPU maps and sysfs entries for a single CPU when its NUMA
1498 * characteristics change. This function doesn't perform any locking and is
1499 * only safe to call from stop_machine().
1501 static int update_cpu_topology(void *data
)
1503 struct topology_update_data
*update
;
1509 cpu
= smp_processor_id();
1511 for (update
= data
; update
; update
= update
->next
) {
1512 int new_nid
= update
->new_nid
;
1513 if (cpu
!= update
->cpu
)
1516 unmap_cpu_from_node(cpu
);
1517 map_cpu_to_node(cpu
, new_nid
);
1518 set_cpu_numa_node(cpu
, new_nid
);
1519 set_cpu_numa_mem(cpu
, local_memory_node(new_nid
));
1526 static int update_lookup_table(void *data
)
1528 struct topology_update_data
*update
;
1534 * Upon topology update, the numa-cpu lookup table needs to be updated
1535 * for all threads in the core, including offline CPUs, to ensure that
1536 * future hotplug operations respect the cpu-to-node associativity
1539 for (update
= data
; update
; update
= update
->next
) {
1542 nid
= update
->new_nid
;
1543 base
= cpu_first_thread_sibling(update
->cpu
);
1545 for (j
= 0; j
< threads_per_core
; j
++) {
1546 update_numa_cpu_lookup_table(base
+ j
, nid
);
1554 * Update the node maps and sysfs entries for each cpu whose home node
1555 * has changed. Returns 1 when the topology has changed, and 0 otherwise.
1557 int arch_update_cpu_topology(void)
1559 unsigned int cpu
, sibling
, changed
= 0;
1560 struct topology_update_data
*updates
, *ud
;
1561 __be32 associativity
[VPHN_ASSOC_BUFSIZE
] = {0};
1562 cpumask_t updated_cpus
;
1564 int weight
, new_nid
, i
= 0;
1566 if (!prrn_enabled
&& !vphn_enabled
)
1569 weight
= cpumask_weight(&cpu_associativity_changes_mask
);
1573 updates
= kzalloc(weight
* (sizeof(*updates
)), GFP_KERNEL
);
1577 cpumask_clear(&updated_cpus
);
1579 for_each_cpu(cpu
, &cpu_associativity_changes_mask
) {
1581 * If siblings aren't flagged for changes, updates list
1582 * will be too short. Skip on this update and set for next
1585 if (!cpumask_subset(cpu_sibling_mask(cpu
),
1586 &cpu_associativity_changes_mask
)) {
1587 pr_info("Sibling bits not set for associativity "
1588 "change, cpu%d\n", cpu
);
1589 cpumask_or(&cpu_associativity_changes_mask
,
1590 &cpu_associativity_changes_mask
,
1591 cpu_sibling_mask(cpu
));
1592 cpu
= cpu_last_thread_sibling(cpu
);
1596 /* Use associativity from first thread for all siblings */
1597 vphn_get_associativity(cpu
, associativity
);
1598 new_nid
= associativity_to_nid(associativity
);
1599 if (new_nid
< 0 || !node_online(new_nid
))
1600 new_nid
= first_online_node
;
1602 if (new_nid
== numa_cpu_lookup_table
[cpu
]) {
1603 cpumask_andnot(&cpu_associativity_changes_mask
,
1604 &cpu_associativity_changes_mask
,
1605 cpu_sibling_mask(cpu
));
1606 cpu
= cpu_last_thread_sibling(cpu
);
1610 for_each_cpu(sibling
, cpu_sibling_mask(cpu
)) {
1613 ud
->new_nid
= new_nid
;
1614 ud
->old_nid
= numa_cpu_lookup_table
[sibling
];
1615 cpumask_set_cpu(sibling
, &updated_cpus
);
1617 ud
->next
= &updates
[i
];
1619 cpu
= cpu_last_thread_sibling(cpu
);
1622 pr_debug("Topology update for the following CPUs:\n");
1623 if (cpumask_weight(&updated_cpus
)) {
1624 for (ud
= &updates
[0]; ud
; ud
= ud
->next
) {
1625 pr_debug("cpu %d moving from node %d "
1627 ud
->old_nid
, ud
->new_nid
);
1632 * In cases where we have nothing to update (because the updates list
1633 * is too short or because the new topology is same as the old one),
1634 * skip invoking update_cpu_topology() via stop-machine(). This is
1635 * necessary (and not just a fast-path optimization) since stop-machine
1636 * can end up electing a random CPU to run update_cpu_topology(), and
1637 * thus trick us into setting up incorrect cpu-node mappings (since
1638 * 'updates' is kzalloc()'ed).
1640 * And for the similar reason, we will skip all the following updating.
1642 if (!cpumask_weight(&updated_cpus
))
1645 stop_machine(update_cpu_topology
, &updates
[0], &updated_cpus
);
1648 * Update the numa-cpu lookup table with the new mappings, even for
1649 * offline CPUs. It is best to perform this update from the stop-
1652 stop_machine(update_lookup_table
, &updates
[0],
1653 cpumask_of(raw_smp_processor_id()));
1655 for (ud
= &updates
[0]; ud
; ud
= ud
->next
) {
1656 unregister_cpu_under_node(ud
->cpu
, ud
->old_nid
);
1657 register_cpu_under_node(ud
->cpu
, ud
->new_nid
);
1659 dev
= get_cpu_device(ud
->cpu
);
1661 kobject_uevent(&dev
->kobj
, KOBJ_CHANGE
);
1662 cpumask_clear_cpu(ud
->cpu
, &cpu_associativity_changes_mask
);
1671 static void topology_work_fn(struct work_struct
*work
)
1673 rebuild_sched_domains();
1675 static DECLARE_WORK(topology_work
, topology_work_fn
);
1677 static void topology_schedule_update(void)
1679 schedule_work(&topology_work
);
1682 static void topology_timer_fn(unsigned long ignored
)
1684 if (prrn_enabled
&& cpumask_weight(&cpu_associativity_changes_mask
))
1685 topology_schedule_update();
1686 else if (vphn_enabled
) {
1687 if (update_cpu_associativity_changes_mask() > 0)
1688 topology_schedule_update();
1689 reset_topology_timer();
1692 static struct timer_list topology_timer
=
1693 TIMER_INITIALIZER(topology_timer_fn
, 0, 0);
1695 static void reset_topology_timer(void)
1697 topology_timer
.data
= 0;
1698 topology_timer
.expires
= jiffies
+ 60 * HZ
;
1699 mod_timer(&topology_timer
, topology_timer
.expires
);
1704 static void stage_topology_update(int core_id
)
1706 cpumask_or(&cpu_associativity_changes_mask
,
1707 &cpu_associativity_changes_mask
, cpu_sibling_mask(core_id
));
1708 reset_topology_timer();
1711 static int dt_update_callback(struct notifier_block
*nb
,
1712 unsigned long action
, void *data
)
1714 struct of_prop_reconfig
*update
;
1715 int rc
= NOTIFY_DONE
;
1718 case OF_RECONFIG_UPDATE_PROPERTY
:
1719 update
= (struct of_prop_reconfig
*)data
;
1720 if (!of_prop_cmp(update
->dn
->type
, "cpu") &&
1721 !of_prop_cmp(update
->prop
->name
, "ibm,associativity")) {
1723 of_property_read_u32(update
->dn
, "reg", &core_id
);
1724 stage_topology_update(core_id
);
1733 static struct notifier_block dt_update_nb
= {
1734 .notifier_call
= dt_update_callback
,
1740 * Start polling for associativity changes.
1742 int start_topology_update(void)
1746 if (firmware_has_feature(FW_FEATURE_PRRN
)) {
1747 if (!prrn_enabled
) {
1751 rc
= of_reconfig_notifier_register(&dt_update_nb
);
1754 } else if (firmware_has_feature(FW_FEATURE_VPHN
) &&
1755 lppaca_shared_proc(get_lppaca())) {
1756 if (!vphn_enabled
) {
1759 setup_cpu_associativity_change_counters();
1760 init_timer_deferrable(&topology_timer
);
1761 reset_topology_timer();
1769 * Disable polling for VPHN associativity changes.
1771 int stop_topology_update(void)
1778 rc
= of_reconfig_notifier_unregister(&dt_update_nb
);
1780 } else if (vphn_enabled
) {
1782 rc
= del_timer_sync(&topology_timer
);
1788 int prrn_is_enabled(void)
1790 return prrn_enabled
;
1793 static int topology_read(struct seq_file
*file
, void *v
)
1795 if (vphn_enabled
|| prrn_enabled
)
1796 seq_puts(file
, "on\n");
1798 seq_puts(file
, "off\n");
1803 static int topology_open(struct inode
*inode
, struct file
*file
)
1805 return single_open(file
, topology_read
, NULL
);
1808 static ssize_t
topology_write(struct file
*file
, const char __user
*buf
,
1809 size_t count
, loff_t
*off
)
1811 char kbuf
[4]; /* "on" or "off" plus null. */
1814 read_len
= count
< 3 ? count
: 3;
1815 if (copy_from_user(kbuf
, buf
, read_len
))
1818 kbuf
[read_len
] = '\0';
1820 if (!strncmp(kbuf
, "on", 2))
1821 start_topology_update();
1822 else if (!strncmp(kbuf
, "off", 3))
1823 stop_topology_update();
1830 static const struct file_operations topology_ops
= {
1832 .write
= topology_write
,
1833 .open
= topology_open
,
1834 .release
= single_release
1837 static int topology_update_init(void)
1839 /* Do not poll for changes if disabled at boot */
1840 if (topology_updates_enabled
)
1841 start_topology_update();
1843 if (!proc_create("powerpc/topology_updates", 0644, NULL
, &topology_ops
))
1848 device_initcall(topology_update_init
);
1849 #endif /* CONFIG_PPC_SPLPAR */