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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * pSeries NUMA support
4 *
5 * Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
6 */
7#define pr_fmt(fmt) "numa: " fmt
8
9#include <linux/threads.h>
10#include <linux/memblock.h>
11#include <linux/init.h>
12#include <linux/mm.h>
13#include <linux/mmzone.h>
14#include <linux/export.h>
15#include <linux/nodemask.h>
16#include <linux/cpu.h>
17#include <linux/notifier.h>
18#include <linux/of.h>
19#include <linux/of_address.h>
20#include <linux/pfn.h>
21#include <linux/cpuset.h>
22#include <linux/node.h>
23#include <linux/stop_machine.h>
24#include <linux/proc_fs.h>
25#include <linux/seq_file.h>
26#include <linux/uaccess.h>
27#include <linux/slab.h>
28#include <asm/cputhreads.h>
29#include <asm/sparsemem.h>
30#include <asm/smp.h>
31#include <asm/topology.h>
32#include <asm/firmware.h>
33#include <asm/paca.h>
34#include <asm/hvcall.h>
35#include <asm/setup.h>
36#include <asm/vdso.h>
37#include <asm/vphn.h>
38#include <asm/drmem.h>
39
40static int numa_enabled = 1;
41
42static char *cmdline __initdata;
43
44int numa_cpu_lookup_table[NR_CPUS];
45cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
46struct pglist_data *node_data[MAX_NUMNODES];
47
48EXPORT_SYMBOL(numa_cpu_lookup_table);
49EXPORT_SYMBOL(node_to_cpumask_map);
50EXPORT_SYMBOL(node_data);
51
52static int primary_domain_index;
53static int n_mem_addr_cells, n_mem_size_cells;
54
55#define FORM0_AFFINITY 0
56#define FORM1_AFFINITY 1
57#define FORM2_AFFINITY 2
58static int affinity_form;
59
60#define MAX_DISTANCE_REF_POINTS 4
61static int distance_ref_points_depth;
62static const __be32 *distance_ref_points;
63static int distance_lookup_table[MAX_NUMNODES][MAX_DISTANCE_REF_POINTS];
64static int numa_distance_table[MAX_NUMNODES][MAX_NUMNODES] = {
65 [0 ... MAX_NUMNODES - 1] = { [0 ... MAX_NUMNODES - 1] = -1 }
66};
67static int numa_id_index_table[MAX_NUMNODES] = { [0 ... MAX_NUMNODES - 1] = NUMA_NO_NODE };
68
69/*
70 * Allocate node_to_cpumask_map based on number of available nodes
71 * Requires node_possible_map to be valid.
72 *
73 * Note: cpumask_of_node() is not valid until after this is done.
74 */
75static void __init setup_node_to_cpumask_map(void)
76{
77 unsigned int node;
78
79 /* setup nr_node_ids if not done yet */
80 if (nr_node_ids == MAX_NUMNODES)
81 setup_nr_node_ids();
82
83 /* allocate the map */
84 for_each_node(node)
85 alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
86
87 /* cpumask_of_node() will now work */
88 pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
89}
90
91static int __init fake_numa_create_new_node(unsigned long end_pfn,
92 unsigned int *nid)
93{
94 unsigned long long mem;
95 char *p = cmdline;
96 static unsigned int fake_nid;
97 static unsigned long long curr_boundary;
98
99 /*
100 * Modify node id, iff we started creating NUMA nodes
101 * We want to continue from where we left of the last time
102 */
103 if (fake_nid)
104 *nid = fake_nid;
105 /*
106 * In case there are no more arguments to parse, the
107 * node_id should be the same as the last fake node id
108 * (we've handled this above).
109 */
110 if (!p)
111 return 0;
112
113 mem = memparse(p, &p);
114 if (!mem)
115 return 0;
116
117 if (mem < curr_boundary)
118 return 0;
119
120 curr_boundary = mem;
121
122 if ((end_pfn << PAGE_SHIFT) > mem) {
123 /*
124 * Skip commas and spaces
125 */
126 while (*p == ',' || *p == ' ' || *p == '\t')
127 p++;
128
129 cmdline = p;
130 fake_nid++;
131 *nid = fake_nid;
132 pr_debug("created new fake_node with id %d\n", fake_nid);
133 return 1;
134 }
135 return 0;
136}
137
138static void __init reset_numa_cpu_lookup_table(void)
139{
140 unsigned int cpu;
141
142 for_each_possible_cpu(cpu)
143 numa_cpu_lookup_table[cpu] = -1;
144}
145
146void map_cpu_to_node(int cpu, int node)
147{
148 update_numa_cpu_lookup_table(cpu, node);
149
150 if (!(cpumask_test_cpu(cpu, node_to_cpumask_map[node]))) {
151 pr_debug("adding cpu %d to node %d\n", cpu, node);
152 cpumask_set_cpu(cpu, node_to_cpumask_map[node]);
153 }
154}
155
156#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PPC_SPLPAR)
157void unmap_cpu_from_node(unsigned long cpu)
158{
159 int node = numa_cpu_lookup_table[cpu];
160
161 if (cpumask_test_cpu(cpu, node_to_cpumask_map[node])) {
162 cpumask_clear_cpu(cpu, node_to_cpumask_map[node]);
163 pr_debug("removing cpu %lu from node %d\n", cpu, node);
164 } else {
165 pr_warn("Warning: cpu %lu not found in node %d\n", cpu, node);
166 }
167}
168#endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */
169
170static int __associativity_to_nid(const __be32 *associativity,
171 int max_array_sz)
172{
173 int nid;
174 /*
175 * primary_domain_index is 1 based array index.
176 */
177 int index = primary_domain_index - 1;
178
179 if (!numa_enabled || index >= max_array_sz)
180 return NUMA_NO_NODE;
181
182 nid = of_read_number(&associativity[index], 1);
183
184 /* POWER4 LPAR uses 0xffff as invalid node */
185 if (nid == 0xffff || nid >= nr_node_ids)
186 nid = NUMA_NO_NODE;
187 return nid;
188}
189/*
190 * Returns nid in the range [0..nr_node_ids], or -1 if no useful NUMA
191 * info is found.
192 */
193static int associativity_to_nid(const __be32 *associativity)
194{
195 int array_sz = of_read_number(associativity, 1);
196
197 /* Skip the first element in the associativity array */
198 return __associativity_to_nid((associativity + 1), array_sz);
199}
200
201static int __cpu_form2_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
202{
203 int dist;
204 int node1, node2;
205
206 node1 = associativity_to_nid(cpu1_assoc);
207 node2 = associativity_to_nid(cpu2_assoc);
208
209 dist = numa_distance_table[node1][node2];
210 if (dist <= LOCAL_DISTANCE)
211 return 0;
212 else if (dist <= REMOTE_DISTANCE)
213 return 1;
214 else
215 return 2;
216}
217
218static int __cpu_form1_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
219{
220 int dist = 0;
221
222 int i, index;
223
224 for (i = 0; i < distance_ref_points_depth; i++) {
225 index = be32_to_cpu(distance_ref_points[i]);
226 if (cpu1_assoc[index] == cpu2_assoc[index])
227 break;
228 dist++;
229 }
230
231 return dist;
232}
233
234int cpu_relative_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
235{
236 /* We should not get called with FORM0 */
237 VM_WARN_ON(affinity_form == FORM0_AFFINITY);
238 if (affinity_form == FORM1_AFFINITY)
239 return __cpu_form1_relative_distance(cpu1_assoc, cpu2_assoc);
240 return __cpu_form2_relative_distance(cpu1_assoc, cpu2_assoc);
241}
242
243/* must hold reference to node during call */
244static const __be32 *of_get_associativity(struct device_node *dev)
245{
246 return of_get_property(dev, "ibm,associativity", NULL);
247}
248
249int __node_distance(int a, int b)
250{
251 int i;
252 int distance = LOCAL_DISTANCE;
253
254 if (affinity_form == FORM2_AFFINITY)
255 return numa_distance_table[a][b];
256 else if (affinity_form == FORM0_AFFINITY)
257 return ((a == b) ? LOCAL_DISTANCE : REMOTE_DISTANCE);
258
259 for (i = 0; i < distance_ref_points_depth; i++) {
260 if (distance_lookup_table[a][i] == distance_lookup_table[b][i])
261 break;
262
263 /* Double the distance for each NUMA level */
264 distance *= 2;
265 }
266
267 return distance;
268}
269EXPORT_SYMBOL(__node_distance);
270
271/* Returns the nid associated with the given device tree node,
272 * or -1 if not found.
273 */
274static int of_node_to_nid_single(struct device_node *device)
275{
276 int nid = NUMA_NO_NODE;
277 const __be32 *tmp;
278
279 tmp = of_get_associativity(device);
280 if (tmp)
281 nid = associativity_to_nid(tmp);
282 return nid;
283}
284
285/* Walk the device tree upwards, looking for an associativity id */
286int of_node_to_nid(struct device_node *device)
287{
288 int nid = NUMA_NO_NODE;
289
290 of_node_get(device);
291 while (device) {
292 nid = of_node_to_nid_single(device);
293 if (nid != -1)
294 break;
295
296 device = of_get_next_parent(device);
297 }
298 of_node_put(device);
299
300 return nid;
301}
302EXPORT_SYMBOL(of_node_to_nid);
303
304static void __initialize_form1_numa_distance(const __be32 *associativity,
305 int max_array_sz)
306{
307 int i, nid;
308
309 if (affinity_form != FORM1_AFFINITY)
310 return;
311
312 nid = __associativity_to_nid(associativity, max_array_sz);
313 if (nid != NUMA_NO_NODE) {
314 for (i = 0; i < distance_ref_points_depth; i++) {
315 const __be32 *entry;
316 int index = be32_to_cpu(distance_ref_points[i]) - 1;
317
318 /*
319 * broken hierarchy, return with broken distance table
320 */
321 if (WARN(index >= max_array_sz, "Broken ibm,associativity property"))
322 return;
323
324 entry = &associativity[index];
325 distance_lookup_table[nid][i] = of_read_number(entry, 1);
326 }
327 }
328}
329
330static void initialize_form1_numa_distance(const __be32 *associativity)
331{
332 int array_sz;
333
334 array_sz = of_read_number(associativity, 1);
335 /* Skip the first element in the associativity array */
336 __initialize_form1_numa_distance(associativity + 1, array_sz);
337}
338
339/*
340 * Used to update distance information w.r.t newly added node.
341 */
342void update_numa_distance(struct device_node *node)
343{
344 int nid;
345
346 if (affinity_form == FORM0_AFFINITY)
347 return;
348 else if (affinity_form == FORM1_AFFINITY) {
349 const __be32 *associativity;
350
351 associativity = of_get_associativity(node);
352 if (!associativity)
353 return;
354
355 initialize_form1_numa_distance(associativity);
356 return;
357 }
358
359 /* FORM2 affinity */
360 nid = of_node_to_nid_single(node);
361 if (nid == NUMA_NO_NODE)
362 return;
363
364 /*
365 * With FORM2 we expect NUMA distance of all possible NUMA
366 * nodes to be provided during boot.
367 */
368 WARN(numa_distance_table[nid][nid] == -1,
369 "NUMA distance details for node %d not provided\n", nid);
370}
371EXPORT_SYMBOL_GPL(update_numa_distance);
372
373/*
374 * ibm,numa-lookup-index-table= {N, domainid1, domainid2, ..... domainidN}
375 * ibm,numa-distance-table = { N, 1, 2, 4, 5, 1, 6, .... N elements}
376 */
377static void __init initialize_form2_numa_distance_lookup_table(void)
378{
379 int i, j;
380 struct device_node *root;
381 const __u8 *form2_distances;
382 const __be32 *numa_lookup_index;
383 int form2_distances_length;
384 int max_numa_index, distance_index;
385
386 if (firmware_has_feature(FW_FEATURE_OPAL))
387 root = of_find_node_by_path("/ibm,opal");
388 else
389 root = of_find_node_by_path("/rtas");
390 if (!root)
391 root = of_find_node_by_path("/");
392
393 numa_lookup_index = of_get_property(root, "ibm,numa-lookup-index-table", NULL);
394 max_numa_index = of_read_number(&numa_lookup_index[0], 1);
395
396 /* first element of the array is the size and is encode-int */
397 form2_distances = of_get_property(root, "ibm,numa-distance-table", NULL);
398 form2_distances_length = of_read_number((const __be32 *)&form2_distances[0], 1);
399 /* Skip the size which is encoded int */
400 form2_distances += sizeof(__be32);
401
402 pr_debug("form2_distances_len = %d, numa_dist_indexes_len = %d\n",
403 form2_distances_length, max_numa_index);
404
405 for (i = 0; i < max_numa_index; i++)
406 /* +1 skip the max_numa_index in the property */
407 numa_id_index_table[i] = of_read_number(&numa_lookup_index[i + 1], 1);
408
409
410 if (form2_distances_length != max_numa_index * max_numa_index) {
411 WARN(1, "Wrong NUMA distance information\n");
412 form2_distances = NULL; // don't use it
413 }
414 distance_index = 0;
415 for (i = 0; i < max_numa_index; i++) {
416 for (j = 0; j < max_numa_index; j++) {
417 int nodeA = numa_id_index_table[i];
418 int nodeB = numa_id_index_table[j];
419 int dist;
420
421 if (form2_distances)
422 dist = form2_distances[distance_index++];
423 else if (nodeA == nodeB)
424 dist = LOCAL_DISTANCE;
425 else
426 dist = REMOTE_DISTANCE;
427 numa_distance_table[nodeA][nodeB] = dist;
428 pr_debug("dist[%d][%d]=%d ", nodeA, nodeB, dist);
429 }
430 }
431
432 of_node_put(root);
433}
434
435static int __init find_primary_domain_index(void)
436{
437 int index;
438 struct device_node *root;
439
440 /*
441 * Check for which form of affinity.
442 */
443 if (firmware_has_feature(FW_FEATURE_OPAL)) {
444 affinity_form = FORM1_AFFINITY;
445 } else if (firmware_has_feature(FW_FEATURE_FORM2_AFFINITY)) {
446 pr_debug("Using form 2 affinity\n");
447 affinity_form = FORM2_AFFINITY;
448 } else if (firmware_has_feature(FW_FEATURE_FORM1_AFFINITY)) {
449 pr_debug("Using form 1 affinity\n");
450 affinity_form = FORM1_AFFINITY;
451 } else
452 affinity_form = FORM0_AFFINITY;
453
454 if (firmware_has_feature(FW_FEATURE_OPAL))
455 root = of_find_node_by_path("/ibm,opal");
456 else
457 root = of_find_node_by_path("/rtas");
458 if (!root)
459 root = of_find_node_by_path("/");
460
461 /*
462 * This property is a set of 32-bit integers, each representing
463 * an index into the ibm,associativity nodes.
464 *
465 * With form 0 affinity the first integer is for an SMP configuration
466 * (should be all 0's) and the second is for a normal NUMA
467 * configuration. We have only one level of NUMA.
468 *
469 * With form 1 affinity the first integer is the most significant
470 * NUMA boundary and the following are progressively less significant
471 * boundaries. There can be more than one level of NUMA.
472 */
473 distance_ref_points = of_get_property(root,
474 "ibm,associativity-reference-points",
475 &distance_ref_points_depth);
476
477 if (!distance_ref_points) {
478 pr_debug("ibm,associativity-reference-points not found.\n");
479 goto err;
480 }
481
482 distance_ref_points_depth /= sizeof(int);
483 if (affinity_form == FORM0_AFFINITY) {
484 if (distance_ref_points_depth < 2) {
485 pr_warn("short ibm,associativity-reference-points\n");
486 goto err;
487 }
488
489 index = of_read_number(&distance_ref_points[1], 1);
490 } else {
491 /*
492 * Both FORM1 and FORM2 affinity find the primary domain details
493 * at the same offset.
494 */
495 index = of_read_number(distance_ref_points, 1);
496 }
497 /*
498 * Warn and cap if the hardware supports more than
499 * MAX_DISTANCE_REF_POINTS domains.
500 */
501 if (distance_ref_points_depth > MAX_DISTANCE_REF_POINTS) {
502 pr_warn("distance array capped at %d entries\n",
503 MAX_DISTANCE_REF_POINTS);
504 distance_ref_points_depth = MAX_DISTANCE_REF_POINTS;
505 }
506
507 of_node_put(root);
508 return index;
509
510err:
511 of_node_put(root);
512 return -1;
513}
514
515static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells)
516{
517 struct device_node *memory = NULL;
518
519 memory = of_find_node_by_type(memory, "memory");
520 if (!memory)
521 panic("numa.c: No memory nodes found!");
522
523 *n_addr_cells = of_n_addr_cells(memory);
524 *n_size_cells = of_n_size_cells(memory);
525 of_node_put(memory);
526}
527
528static unsigned long read_n_cells(int n, const __be32 **buf)
529{
530 unsigned long result = 0;
531
532 while (n--) {
533 result = (result << 32) | of_read_number(*buf, 1);
534 (*buf)++;
535 }
536 return result;
537}
538
539struct assoc_arrays {
540 u32 n_arrays;
541 u32 array_sz;
542 const __be32 *arrays;
543};
544
545/*
546 * Retrieve and validate the list of associativity arrays for drconf
547 * memory from the ibm,associativity-lookup-arrays property of the
548 * device tree..
549 *
550 * The layout of the ibm,associativity-lookup-arrays property is a number N
551 * indicating the number of associativity arrays, followed by a number M
552 * indicating the size of each associativity array, followed by a list
553 * of N associativity arrays.
554 */
555static int of_get_assoc_arrays(struct assoc_arrays *aa)
556{
557 struct device_node *memory;
558 const __be32 *prop;
559 u32 len;
560
561 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
562 if (!memory)
563 return -1;
564
565 prop = of_get_property(memory, "ibm,associativity-lookup-arrays", &len);
566 if (!prop || len < 2 * sizeof(unsigned int)) {
567 of_node_put(memory);
568 return -1;
569 }
570
571 aa->n_arrays = of_read_number(prop++, 1);
572 aa->array_sz = of_read_number(prop++, 1);
573
574 of_node_put(memory);
575
576 /* Now that we know the number of arrays and size of each array,
577 * revalidate the size of the property read in.
578 */
579 if (len < (aa->n_arrays * aa->array_sz + 2) * sizeof(unsigned int))
580 return -1;
581
582 aa->arrays = prop;
583 return 0;
584}
585
586static int __init get_nid_and_numa_distance(struct drmem_lmb *lmb)
587{
588 struct assoc_arrays aa = { .arrays = NULL };
589 int default_nid = NUMA_NO_NODE;
590 int nid = default_nid;
591 int rc, index;
592
593 if ((primary_domain_index < 0) || !numa_enabled)
594 return default_nid;
595
596 rc = of_get_assoc_arrays(&aa);
597 if (rc)
598 return default_nid;
599
600 if (primary_domain_index <= aa.array_sz &&
601 !(lmb->flags & DRCONF_MEM_AI_INVALID) && lmb->aa_index < aa.n_arrays) {
602 const __be32 *associativity;
603
604 index = lmb->aa_index * aa.array_sz;
605 associativity = &aa.arrays[index];
606 nid = __associativity_to_nid(associativity, aa.array_sz);
607 if (nid > 0 && affinity_form == FORM1_AFFINITY) {
608 /*
609 * lookup array associativity entries have
610 * no length of the array as the first element.
611 */
612 __initialize_form1_numa_distance(associativity, aa.array_sz);
613 }
614 }
615 return nid;
616}
617
618/*
619 * This is like of_node_to_nid_single() for memory represented in the
620 * ibm,dynamic-reconfiguration-memory node.
621 */
622int of_drconf_to_nid_single(struct drmem_lmb *lmb)
623{
624 struct assoc_arrays aa = { .arrays = NULL };
625 int default_nid = NUMA_NO_NODE;
626 int nid = default_nid;
627 int rc, index;
628
629 if ((primary_domain_index < 0) || !numa_enabled)
630 return default_nid;
631
632 rc = of_get_assoc_arrays(&aa);
633 if (rc)
634 return default_nid;
635
636 if (primary_domain_index <= aa.array_sz &&
637 !(lmb->flags & DRCONF_MEM_AI_INVALID) && lmb->aa_index < aa.n_arrays) {
638 const __be32 *associativity;
639
640 index = lmb->aa_index * aa.array_sz;
641 associativity = &aa.arrays[index];
642 nid = __associativity_to_nid(associativity, aa.array_sz);
643 }
644 return nid;
645}
646
647#ifdef CONFIG_PPC_SPLPAR
648
649static int __vphn_get_associativity(long lcpu, __be32 *associativity)
650{
651 long rc, hwid;
652
653 /*
654 * On a shared lpar, device tree will not have node associativity.
655 * At this time lppaca, or its __old_status field may not be
656 * updated. Hence kernel cannot detect if its on a shared lpar. So
657 * request an explicit associativity irrespective of whether the
658 * lpar is shared or dedicated. Use the device tree property as a
659 * fallback. cpu_to_phys_id is only valid between
660 * smp_setup_cpu_maps() and smp_setup_pacas().
661 */
662 if (firmware_has_feature(FW_FEATURE_VPHN)) {
663 if (cpu_to_phys_id)
664 hwid = cpu_to_phys_id[lcpu];
665 else
666 hwid = get_hard_smp_processor_id(lcpu);
667
668 rc = hcall_vphn(hwid, VPHN_FLAG_VCPU, associativity);
669 if (rc == H_SUCCESS)
670 return 0;
671 }
672
673 return -1;
674}
675
676static int vphn_get_nid(long lcpu)
677{
678 __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
679
680
681 if (!__vphn_get_associativity(lcpu, associativity))
682 return associativity_to_nid(associativity);
683
684 return NUMA_NO_NODE;
685
686}
687#else
688
689static int __vphn_get_associativity(long lcpu, __be32 *associativity)
690{
691 return -1;
692}
693
694static int vphn_get_nid(long unused)
695{
696 return NUMA_NO_NODE;
697}
698#endif /* CONFIG_PPC_SPLPAR */
699
700/*
701 * Figure out to which domain a cpu belongs and stick it there.
702 * Return the id of the domain used.
703 */
704static int numa_setup_cpu(unsigned long lcpu)
705{
706 struct device_node *cpu;
707 int fcpu = cpu_first_thread_sibling(lcpu);
708 int nid = NUMA_NO_NODE;
709
710 if (!cpu_present(lcpu)) {
711 set_cpu_numa_node(lcpu, first_online_node);
712 return first_online_node;
713 }
714
715 /*
716 * If a valid cpu-to-node mapping is already available, use it
717 * directly instead of querying the firmware, since it represents
718 * the most recent mapping notified to us by the platform (eg: VPHN).
719 * Since cpu_to_node binding remains the same for all threads in the
720 * core. If a valid cpu-to-node mapping is already available, for
721 * the first thread in the core, use it.
722 */
723 nid = numa_cpu_lookup_table[fcpu];
724 if (nid >= 0) {
725 map_cpu_to_node(lcpu, nid);
726 return nid;
727 }
728
729 nid = vphn_get_nid(lcpu);
730 if (nid != NUMA_NO_NODE)
731 goto out_present;
732
733 cpu = of_get_cpu_node(lcpu, NULL);
734
735 if (!cpu) {
736 WARN_ON(1);
737 if (cpu_present(lcpu))
738 goto out_present;
739 else
740 goto out;
741 }
742
743 nid = of_node_to_nid_single(cpu);
744 of_node_put(cpu);
745
746out_present:
747 if (nid < 0 || !node_possible(nid))
748 nid = first_online_node;
749
750 /*
751 * Update for the first thread of the core. All threads of a core
752 * have to be part of the same node. This not only avoids querying
753 * for every other thread in the core, but always avoids a case
754 * where virtual node associativity change causes subsequent threads
755 * of a core to be associated with different nid. However if first
756 * thread is already online, expect it to have a valid mapping.
757 */
758 if (fcpu != lcpu) {
759 WARN_ON(cpu_online(fcpu));
760 map_cpu_to_node(fcpu, nid);
761 }
762
763 map_cpu_to_node(lcpu, nid);
764out:
765 return nid;
766}
767
768static void verify_cpu_node_mapping(int cpu, int node)
769{
770 int base, sibling, i;
771
772 /* Verify that all the threads in the core belong to the same node */
773 base = cpu_first_thread_sibling(cpu);
774
775 for (i = 0; i < threads_per_core; i++) {
776 sibling = base + i;
777
778 if (sibling == cpu || cpu_is_offline(sibling))
779 continue;
780
781 if (cpu_to_node(sibling) != node) {
782 WARN(1, "CPU thread siblings %d and %d don't belong"
783 " to the same node!\n", cpu, sibling);
784 break;
785 }
786 }
787}
788
789/* Must run before sched domains notifier. */
790static int ppc_numa_cpu_prepare(unsigned int cpu)
791{
792 int nid;
793
794 nid = numa_setup_cpu(cpu);
795 verify_cpu_node_mapping(cpu, nid);
796 return 0;
797}
798
799static int ppc_numa_cpu_dead(unsigned int cpu)
800{
801 return 0;
802}
803
804/*
805 * Check and possibly modify a memory region to enforce the memory limit.
806 *
807 * Returns the size the region should have to enforce the memory limit.
808 * This will either be the original value of size, a truncated value,
809 * or zero. If the returned value of size is 0 the region should be
810 * discarded as it lies wholly above the memory limit.
811 */
812static unsigned long __init numa_enforce_memory_limit(unsigned long start,
813 unsigned long size)
814{
815 /*
816 * We use memblock_end_of_DRAM() in here instead of memory_limit because
817 * we've already adjusted it for the limit and it takes care of
818 * having memory holes below the limit. Also, in the case of
819 * iommu_is_off, memory_limit is not set but is implicitly enforced.
820 */
821
822 if (start + size <= memblock_end_of_DRAM())
823 return size;
824
825 if (start >= memblock_end_of_DRAM())
826 return 0;
827
828 return memblock_end_of_DRAM() - start;
829}
830
831/*
832 * Reads the counter for a given entry in
833 * linux,drconf-usable-memory property
834 */
835static inline int __init read_usm_ranges(const __be32 **usm)
836{
837 /*
838 * For each lmb in ibm,dynamic-memory a corresponding
839 * entry in linux,drconf-usable-memory property contains
840 * a counter followed by that many (base, size) duple.
841 * read the counter from linux,drconf-usable-memory
842 */
843 return read_n_cells(n_mem_size_cells, usm);
844}
845
846/*
847 * Extract NUMA information from the ibm,dynamic-reconfiguration-memory
848 * node. This assumes n_mem_{addr,size}_cells have been set.
849 */
850static int __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
851 const __be32 **usm,
852 void *data)
853{
854 unsigned int ranges, is_kexec_kdump = 0;
855 unsigned long base, size, sz;
856 int nid;
857
858 /*
859 * Skip this block if the reserved bit is set in flags (0x80)
860 * or if the block is not assigned to this partition (0x8)
861 */
862 if ((lmb->flags & DRCONF_MEM_RESERVED)
863 || !(lmb->flags & DRCONF_MEM_ASSIGNED))
864 return 0;
865
866 if (*usm)
867 is_kexec_kdump = 1;
868
869 base = lmb->base_addr;
870 size = drmem_lmb_size();
871 ranges = 1;
872
873 if (is_kexec_kdump) {
874 ranges = read_usm_ranges(usm);
875 if (!ranges) /* there are no (base, size) duple */
876 return 0;
877 }
878
879 do {
880 if (is_kexec_kdump) {
881 base = read_n_cells(n_mem_addr_cells, usm);
882 size = read_n_cells(n_mem_size_cells, usm);
883 }
884
885 nid = get_nid_and_numa_distance(lmb);
886 fake_numa_create_new_node(((base + size) >> PAGE_SHIFT),
887 &nid);
888 node_set_online(nid);
889 sz = numa_enforce_memory_limit(base, size);
890 if (sz)
891 memblock_set_node(base, sz, &memblock.memory, nid);
892 } while (--ranges);
893
894 return 0;
895}
896
897static int __init parse_numa_properties(void)
898{
899 struct device_node *memory;
900 int default_nid = 0;
901 unsigned long i;
902 const __be32 *associativity;
903
904 if (numa_enabled == 0) {
905 pr_warn("disabled by user\n");
906 return -1;
907 }
908
909 primary_domain_index = find_primary_domain_index();
910
911 if (primary_domain_index < 0) {
912 /*
913 * if we fail to parse primary_domain_index from device tree
914 * mark the numa disabled, boot with numa disabled.
915 */
916 numa_enabled = false;
917 return primary_domain_index;
918 }
919
920 pr_debug("associativity depth for CPU/Memory: %d\n", primary_domain_index);
921
922 /*
923 * If it is FORM2 initialize the distance table here.
924 */
925 if (affinity_form == FORM2_AFFINITY)
926 initialize_form2_numa_distance_lookup_table();
927
928 /*
929 * Even though we connect cpus to numa domains later in SMP
930 * init, we need to know the node ids now. This is because
931 * each node to be onlined must have NODE_DATA etc backing it.
932 */
933 for_each_present_cpu(i) {
934 __be32 vphn_assoc[VPHN_ASSOC_BUFSIZE];
935 struct device_node *cpu;
936 int nid = NUMA_NO_NODE;
937
938 memset(vphn_assoc, 0, VPHN_ASSOC_BUFSIZE * sizeof(__be32));
939
940 if (__vphn_get_associativity(i, vphn_assoc) == 0) {
941 nid = associativity_to_nid(vphn_assoc);
942 initialize_form1_numa_distance(vphn_assoc);
943 } else {
944
945 /*
946 * Don't fall back to default_nid yet -- we will plug
947 * cpus into nodes once the memory scan has discovered
948 * the topology.
949 */
950 cpu = of_get_cpu_node(i, NULL);
951 BUG_ON(!cpu);
952
953 associativity = of_get_associativity(cpu);
954 if (associativity) {
955 nid = associativity_to_nid(associativity);
956 initialize_form1_numa_distance(associativity);
957 }
958 of_node_put(cpu);
959 }
960
961 /* node_set_online() is an UB if 'nid' is negative */
962 if (likely(nid >= 0))
963 node_set_online(nid);
964 }
965
966 get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells);
967
968 for_each_node_by_type(memory, "memory") {
969 unsigned long start;
970 unsigned long size;
971 int nid;
972 int ranges;
973 const __be32 *memcell_buf;
974 unsigned int len;
975
976 memcell_buf = of_get_property(memory,
977 "linux,usable-memory", &len);
978 if (!memcell_buf || len <= 0)
979 memcell_buf = of_get_property(memory, "reg", &len);
980 if (!memcell_buf || len <= 0)
981 continue;
982
983 /* ranges in cell */
984 ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
985new_range:
986 /* these are order-sensitive, and modify the buffer pointer */
987 start = read_n_cells(n_mem_addr_cells, &memcell_buf);
988 size = read_n_cells(n_mem_size_cells, &memcell_buf);
989
990 /*
991 * Assumption: either all memory nodes or none will
992 * have associativity properties. If none, then
993 * everything goes to default_nid.
994 */
995 associativity = of_get_associativity(memory);
996 if (associativity) {
997 nid = associativity_to_nid(associativity);
998 initialize_form1_numa_distance(associativity);
999 } else
1000 nid = default_nid;
1001
1002 fake_numa_create_new_node(((start + size) >> PAGE_SHIFT), &nid);
1003 node_set_online(nid);
1004
1005 size = numa_enforce_memory_limit(start, size);
1006 if (size)
1007 memblock_set_node(start, size, &memblock.memory, nid);
1008
1009 if (--ranges)
1010 goto new_range;
1011 }
1012
1013 /*
1014 * Now do the same thing for each MEMBLOCK listed in the
1015 * ibm,dynamic-memory property in the
1016 * ibm,dynamic-reconfiguration-memory node.
1017 */
1018 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1019 if (memory) {
1020 walk_drmem_lmbs(memory, NULL, numa_setup_drmem_lmb);
1021 of_node_put(memory);
1022 }
1023
1024 return 0;
1025}
1026
1027static void __init setup_nonnuma(void)
1028{
1029 unsigned long top_of_ram = memblock_end_of_DRAM();
1030 unsigned long total_ram = memblock_phys_mem_size();
1031 unsigned long start_pfn, end_pfn;
1032 unsigned int nid = 0;
1033 int i;
1034
1035 pr_debug("Top of RAM: 0x%lx, Total RAM: 0x%lx\n", top_of_ram, total_ram);
1036 pr_debug("Memory hole size: %ldMB\n", (top_of_ram - total_ram) >> 20);
1037
1038 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
1039 fake_numa_create_new_node(end_pfn, &nid);
1040 memblock_set_node(PFN_PHYS(start_pfn),
1041 PFN_PHYS(end_pfn - start_pfn),
1042 &memblock.memory, nid);
1043 node_set_online(nid);
1044 }
1045}
1046
1047void __init dump_numa_cpu_topology(void)
1048{
1049 unsigned int node;
1050 unsigned int cpu, count;
1051
1052 if (!numa_enabled)
1053 return;
1054
1055 for_each_online_node(node) {
1056 pr_info("Node %d CPUs:", node);
1057
1058 count = 0;
1059 /*
1060 * If we used a CPU iterator here we would miss printing
1061 * the holes in the cpumap.
1062 */
1063 for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
1064 if (cpumask_test_cpu(cpu,
1065 node_to_cpumask_map[node])) {
1066 if (count == 0)
1067 pr_cont(" %u", cpu);
1068 ++count;
1069 } else {
1070 if (count > 1)
1071 pr_cont("-%u", cpu - 1);
1072 count = 0;
1073 }
1074 }
1075
1076 if (count > 1)
1077 pr_cont("-%u", nr_cpu_ids - 1);
1078 pr_cont("\n");
1079 }
1080}
1081
1082/* Initialize NODE_DATA for a node on the local memory */
1083static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
1084{
1085 u64 spanned_pages = end_pfn - start_pfn;
1086 const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
1087 u64 nd_pa;
1088 void *nd;
1089 int tnid;
1090
1091 nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
1092 if (!nd_pa)
1093 panic("Cannot allocate %zu bytes for node %d data\n",
1094 nd_size, nid);
1095
1096 nd = __va(nd_pa);
1097
1098 /* report and initialize */
1099 pr_info(" NODE_DATA [mem %#010Lx-%#010Lx]\n",
1100 nd_pa, nd_pa + nd_size - 1);
1101 tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
1102 if (tnid != nid)
1103 pr_info(" NODE_DATA(%d) on node %d\n", nid, tnid);
1104
1105 node_data[nid] = nd;
1106 memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
1107 NODE_DATA(nid)->node_id = nid;
1108 NODE_DATA(nid)->node_start_pfn = start_pfn;
1109 NODE_DATA(nid)->node_spanned_pages = spanned_pages;
1110}
1111
1112static void __init find_possible_nodes(void)
1113{
1114 struct device_node *rtas;
1115 const __be32 *domains = NULL;
1116 int prop_length, max_nodes;
1117 u32 i;
1118
1119 if (!numa_enabled)
1120 return;
1121
1122 rtas = of_find_node_by_path("/rtas");
1123 if (!rtas)
1124 return;
1125
1126 /*
1127 * ibm,current-associativity-domains is a fairly recent property. If
1128 * it doesn't exist, then fallback on ibm,max-associativity-domains.
1129 * Current denotes what the platform can support compared to max
1130 * which denotes what the Hypervisor can support.
1131 *
1132 * If the LPAR is migratable, new nodes might be activated after a LPM,
1133 * so we should consider the max number in that case.
1134 */
1135 if (!of_get_property(of_root, "ibm,migratable-partition", NULL))
1136 domains = of_get_property(rtas,
1137 "ibm,current-associativity-domains",
1138 &prop_length);
1139 if (!domains) {
1140 domains = of_get_property(rtas, "ibm,max-associativity-domains",
1141 &prop_length);
1142 if (!domains)
1143 goto out;
1144 }
1145
1146 max_nodes = of_read_number(&domains[primary_domain_index], 1);
1147 pr_info("Partition configured for %d NUMA nodes.\n", max_nodes);
1148
1149 for (i = 0; i < max_nodes; i++) {
1150 if (!node_possible(i))
1151 node_set(i, node_possible_map);
1152 }
1153
1154 prop_length /= sizeof(int);
1155 if (prop_length > primary_domain_index + 2)
1156 coregroup_enabled = 1;
1157
1158out:
1159 of_node_put(rtas);
1160}
1161
1162void __init mem_topology_setup(void)
1163{
1164 int cpu;
1165
1166 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
1167 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
1168
1169 /*
1170 * Linux/mm assumes node 0 to be online at boot. However this is not
1171 * true on PowerPC, where node 0 is similar to any other node, it
1172 * could be cpuless, memoryless node. So force node 0 to be offline
1173 * for now. This will prevent cpuless, memoryless node 0 showing up
1174 * unnecessarily as online. If a node has cpus or memory that need
1175 * to be online, then node will anyway be marked online.
1176 */
1177 node_set_offline(0);
1178
1179 if (parse_numa_properties())
1180 setup_nonnuma();
1181
1182 /*
1183 * Modify the set of possible NUMA nodes to reflect information
1184 * available about the set of online nodes, and the set of nodes
1185 * that we expect to make use of for this platform's affinity
1186 * calculations.
1187 */
1188 nodes_and(node_possible_map, node_possible_map, node_online_map);
1189
1190 find_possible_nodes();
1191
1192 setup_node_to_cpumask_map();
1193
1194 reset_numa_cpu_lookup_table();
1195
1196 for_each_possible_cpu(cpu) {
1197 /*
1198 * Powerpc with CONFIG_NUMA always used to have a node 0,
1199 * even if it was memoryless or cpuless. For all cpus that
1200 * are possible but not present, cpu_to_node() would point
1201 * to node 0. To remove a cpuless, memoryless dummy node,
1202 * powerpc need to make sure all possible but not present
1203 * cpu_to_node are set to a proper node.
1204 */
1205 numa_setup_cpu(cpu);
1206 }
1207}
1208
1209void __init initmem_init(void)
1210{
1211 int nid;
1212
1213 memblock_dump_all();
1214
1215 for_each_online_node(nid) {
1216 unsigned long start_pfn, end_pfn;
1217
1218 get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
1219 setup_node_data(nid, start_pfn, end_pfn);
1220 }
1221
1222 sparse_init();
1223
1224 /*
1225 * We need the numa_cpu_lookup_table to be accurate for all CPUs,
1226 * even before we online them, so that we can use cpu_to_{node,mem}
1227 * early in boot, cf. smp_prepare_cpus().
1228 * _nocalls() + manual invocation is used because cpuhp is not yet
1229 * initialized for the boot CPU.
1230 */
1231 cpuhp_setup_state_nocalls(CPUHP_POWER_NUMA_PREPARE, "powerpc/numa:prepare",
1232 ppc_numa_cpu_prepare, ppc_numa_cpu_dead);
1233}
1234
1235static int __init early_numa(char *p)
1236{
1237 if (!p)
1238 return 0;
1239
1240 if (strstr(p, "off"))
1241 numa_enabled = 0;
1242
1243 p = strstr(p, "fake=");
1244 if (p)
1245 cmdline = p + strlen("fake=");
1246
1247 return 0;
1248}
1249early_param("numa", early_numa);
1250
1251#ifdef CONFIG_MEMORY_HOTPLUG
1252/*
1253 * Find the node associated with a hot added memory section for
1254 * memory represented in the device tree by the property
1255 * ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory.
1256 */
1257static int hot_add_drconf_scn_to_nid(unsigned long scn_addr)
1258{
1259 struct drmem_lmb *lmb;
1260 unsigned long lmb_size;
1261 int nid = NUMA_NO_NODE;
1262
1263 lmb_size = drmem_lmb_size();
1264
1265 for_each_drmem_lmb(lmb) {
1266 /* skip this block if it is reserved or not assigned to
1267 * this partition */
1268 if ((lmb->flags & DRCONF_MEM_RESERVED)
1269 || !(lmb->flags & DRCONF_MEM_ASSIGNED))
1270 continue;
1271
1272 if ((scn_addr < lmb->base_addr)
1273 || (scn_addr >= (lmb->base_addr + lmb_size)))
1274 continue;
1275
1276 nid = of_drconf_to_nid_single(lmb);
1277 break;
1278 }
1279
1280 return nid;
1281}
1282
1283/*
1284 * Find the node associated with a hot added memory section for memory
1285 * represented in the device tree as a node (i.e. memory@XXXX) for
1286 * each memblock.
1287 */
1288static int hot_add_node_scn_to_nid(unsigned long scn_addr)
1289{
1290 struct device_node *memory;
1291 int nid = NUMA_NO_NODE;
1292
1293 for_each_node_by_type(memory, "memory") {
1294 int i = 0;
1295
1296 while (1) {
1297 struct resource res;
1298
1299 if (of_address_to_resource(memory, i++, &res))
1300 break;
1301
1302 if ((scn_addr < res.start) || (scn_addr > res.end))
1303 continue;
1304
1305 nid = of_node_to_nid_single(memory);
1306 break;
1307 }
1308
1309 if (nid >= 0)
1310 break;
1311 }
1312
1313 of_node_put(memory);
1314
1315 return nid;
1316}
1317
1318/*
1319 * Find the node associated with a hot added memory section. Section
1320 * corresponds to a SPARSEMEM section, not an MEMBLOCK. It is assumed that
1321 * sections are fully contained within a single MEMBLOCK.
1322 */
1323int hot_add_scn_to_nid(unsigned long scn_addr)
1324{
1325 struct device_node *memory = NULL;
1326 int nid;
1327
1328 if (!numa_enabled)
1329 return first_online_node;
1330
1331 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1332 if (memory) {
1333 nid = hot_add_drconf_scn_to_nid(scn_addr);
1334 of_node_put(memory);
1335 } else {
1336 nid = hot_add_node_scn_to_nid(scn_addr);
1337 }
1338
1339 if (nid < 0 || !node_possible(nid))
1340 nid = first_online_node;
1341
1342 return nid;
1343}
1344
1345static u64 hot_add_drconf_memory_max(void)
1346{
1347 struct device_node *memory = NULL;
1348 struct device_node *dn = NULL;
1349 const __be64 *lrdr = NULL;
1350
1351 dn = of_find_node_by_path("/rtas");
1352 if (dn) {
1353 lrdr = of_get_property(dn, "ibm,lrdr-capacity", NULL);
1354 of_node_put(dn);
1355 if (lrdr)
1356 return be64_to_cpup(lrdr);
1357 }
1358
1359 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1360 if (memory) {
1361 of_node_put(memory);
1362 return drmem_lmb_memory_max();
1363 }
1364 return 0;
1365}
1366
1367/*
1368 * memory_hotplug_max - return max address of memory that may be added
1369 *
1370 * This is currently only used on systems that support drconfig memory
1371 * hotplug.
1372 */
1373u64 memory_hotplug_max(void)
1374{
1375 return max(hot_add_drconf_memory_max(), memblock_end_of_DRAM());
1376}
1377#endif /* CONFIG_MEMORY_HOTPLUG */
1378
1379/* Virtual Processor Home Node (VPHN) support */
1380#ifdef CONFIG_PPC_SPLPAR
1381static int topology_inited;
1382
1383/*
1384 * Retrieve the new associativity information for a virtual processor's
1385 * home node.
1386 */
1387static long vphn_get_associativity(unsigned long cpu,
1388 __be32 *associativity)
1389{
1390 long rc;
1391
1392 rc = hcall_vphn(get_hard_smp_processor_id(cpu),
1393 VPHN_FLAG_VCPU, associativity);
1394
1395 switch (rc) {
1396 case H_SUCCESS:
1397 pr_debug("VPHN hcall succeeded. Reset polling...\n");
1398 goto out;
1399
1400 case H_FUNCTION:
1401 pr_err_ratelimited("VPHN unsupported. Disabling polling...\n");
1402 break;
1403 case H_HARDWARE:
1404 pr_err_ratelimited("hcall_vphn() experienced a hardware fault "
1405 "preventing VPHN. Disabling polling...\n");
1406 break;
1407 case H_PARAMETER:
1408 pr_err_ratelimited("hcall_vphn() was passed an invalid parameter. "
1409 "Disabling polling...\n");
1410 break;
1411 default:
1412 pr_err_ratelimited("hcall_vphn() returned %ld. Disabling polling...\n"
1413 , rc);
1414 break;
1415 }
1416out:
1417 return rc;
1418}
1419
1420void find_and_update_cpu_nid(int cpu)
1421{
1422 __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
1423 int new_nid;
1424
1425 /* Use associativity from first thread for all siblings */
1426 if (vphn_get_associativity(cpu, associativity))
1427 return;
1428
1429 /* Do not have previous associativity, so find it now. */
1430 new_nid = associativity_to_nid(associativity);
1431
1432 if (new_nid < 0 || !node_possible(new_nid))
1433 new_nid = first_online_node;
1434 else
1435 // Associate node <-> cpu, so cpu_up() calls
1436 // try_online_node() on the right node.
1437 set_cpu_numa_node(cpu, new_nid);
1438
1439 pr_debug("%s:%d cpu %d nid %d\n", __func__, __LINE__, cpu, new_nid);
1440}
1441
1442int cpu_to_coregroup_id(int cpu)
1443{
1444 __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
1445 int index;
1446
1447 if (cpu < 0 || cpu > nr_cpu_ids)
1448 return -1;
1449
1450 if (!coregroup_enabled)
1451 goto out;
1452
1453 if (!firmware_has_feature(FW_FEATURE_VPHN))
1454 goto out;
1455
1456 if (vphn_get_associativity(cpu, associativity))
1457 goto out;
1458
1459 index = of_read_number(associativity, 1);
1460 if (index > primary_domain_index + 1)
1461 return of_read_number(&associativity[index - 1], 1);
1462
1463out:
1464 return cpu_to_core_id(cpu);
1465}
1466
1467static int topology_update_init(void)
1468{
1469 topology_inited = 1;
1470 return 0;
1471}
1472device_initcall(topology_update_init);
1473#endif /* CONFIG_PPC_SPLPAR */
1/*
2 * pSeries NUMA support
3 *
4 * Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
5 *
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.
10 */
11#define pr_fmt(fmt) "numa: " fmt
12
13#include <linux/threads.h>
14#include <linux/bootmem.h>
15#include <linux/init.h>
16#include <linux/mm.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>
23#include <linux/of.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>
34#include <asm/prom.h>
35#include <asm/smp.h>
36#include <asm/cputhreads.h>
37#include <asm/topology.h>
38#include <asm/firmware.h>
39#include <asm/paca.h>
40#include <asm/hvcall.h>
41#include <asm/setup.h>
42#include <asm/vdso.h>
43#include <asm/drmem.h>
44
45static int numa_enabled = 1;
46
47static char *cmdline __initdata;
48
49static int numa_debug;
50#define dbg(args...) if (numa_debug) { printk(KERN_INFO args); }
51
52int numa_cpu_lookup_table[NR_CPUS];
53cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
54struct pglist_data *node_data[MAX_NUMNODES];
55
56EXPORT_SYMBOL(numa_cpu_lookup_table);
57EXPORT_SYMBOL(node_to_cpumask_map);
58EXPORT_SYMBOL(node_data);
59
60static int min_common_depth;
61static int n_mem_addr_cells, n_mem_size_cells;
62static int form1_affinity;
63
64#define MAX_DISTANCE_REF_POINTS 4
65static int distance_ref_points_depth;
66static const __be32 *distance_ref_points;
67static int distance_lookup_table[MAX_NUMNODES][MAX_DISTANCE_REF_POINTS];
68
69/*
70 * Allocate node_to_cpumask_map based on number of available nodes
71 * Requires node_possible_map to be valid.
72 *
73 * Note: cpumask_of_node() is not valid until after this is done.
74 */
75static void __init setup_node_to_cpumask_map(void)
76{
77 unsigned int node;
78
79 /* setup nr_node_ids if not done yet */
80 if (nr_node_ids == MAX_NUMNODES)
81 setup_nr_node_ids();
82
83 /* allocate the map */
84 for_each_node(node)
85 alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
86
87 /* cpumask_of_node() will now work */
88 dbg("Node to cpumask map for %d nodes\n", nr_node_ids);
89}
90
91static int __init fake_numa_create_new_node(unsigned long end_pfn,
92 unsigned int *nid)
93{
94 unsigned long long mem;
95 char *p = cmdline;
96 static unsigned int fake_nid;
97 static unsigned long long curr_boundary;
98
99 /*
100 * Modify node id, iff we started creating NUMA nodes
101 * We want to continue from where we left of the last time
102 */
103 if (fake_nid)
104 *nid = fake_nid;
105 /*
106 * In case there are no more arguments to parse, the
107 * node_id should be the same as the last fake node id
108 * (we've handled this above).
109 */
110 if (!p)
111 return 0;
112
113 mem = memparse(p, &p);
114 if (!mem)
115 return 0;
116
117 if (mem < curr_boundary)
118 return 0;
119
120 curr_boundary = mem;
121
122 if ((end_pfn << PAGE_SHIFT) > mem) {
123 /*
124 * Skip commas and spaces
125 */
126 while (*p == ',' || *p == ' ' || *p == '\t')
127 p++;
128
129 cmdline = p;
130 fake_nid++;
131 *nid = fake_nid;
132 dbg("created new fake_node with id %d\n", fake_nid);
133 return 1;
134 }
135 return 0;
136}
137
138static void reset_numa_cpu_lookup_table(void)
139{
140 unsigned int cpu;
141
142 for_each_possible_cpu(cpu)
143 numa_cpu_lookup_table[cpu] = -1;
144}
145
146static void map_cpu_to_node(int cpu, int node)
147{
148 update_numa_cpu_lookup_table(cpu, node);
149
150 dbg("adding cpu %d to node %d\n", cpu, node);
151
152 if (!(cpumask_test_cpu(cpu, node_to_cpumask_map[node])))
153 cpumask_set_cpu(cpu, node_to_cpumask_map[node]);
154}
155
156#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PPC_SPLPAR)
157static void unmap_cpu_from_node(unsigned long cpu)
158{
159 int node = numa_cpu_lookup_table[cpu];
160
161 dbg("removing cpu %lu from node %d\n", cpu, node);
162
163 if (cpumask_test_cpu(cpu, node_to_cpumask_map[node])) {
164 cpumask_clear_cpu(cpu, node_to_cpumask_map[node]);
165 } else {
166 printk(KERN_ERR "WARNING: cpu %lu not found in node %d\n",
167 cpu, node);
168 }
169}
170#endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */
171
172/* must hold reference to node during call */
173static const __be32 *of_get_associativity(struct device_node *dev)
174{
175 return of_get_property(dev, "ibm,associativity", NULL);
176}
177
178int __node_distance(int a, int b)
179{
180 int i;
181 int distance = LOCAL_DISTANCE;
182
183 if (!form1_affinity)
184 return ((a == b) ? LOCAL_DISTANCE : REMOTE_DISTANCE);
185
186 for (i = 0; i < distance_ref_points_depth; i++) {
187 if (distance_lookup_table[a][i] == distance_lookup_table[b][i])
188 break;
189
190 /* Double the distance for each NUMA level */
191 distance *= 2;
192 }
193
194 return distance;
195}
196EXPORT_SYMBOL(__node_distance);
197
198static void initialize_distance_lookup_table(int nid,
199 const __be32 *associativity)
200{
201 int i;
202
203 if (!form1_affinity)
204 return;
205
206 for (i = 0; i < distance_ref_points_depth; i++) {
207 const __be32 *entry;
208
209 entry = &associativity[be32_to_cpu(distance_ref_points[i]) - 1];
210 distance_lookup_table[nid][i] = of_read_number(entry, 1);
211 }
212}
213
214/* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
215 * info is found.
216 */
217static int associativity_to_nid(const __be32 *associativity)
218{
219 int nid = -1;
220
221 if (min_common_depth == -1)
222 goto out;
223
224 if (of_read_number(associativity, 1) >= min_common_depth)
225 nid = of_read_number(&associativity[min_common_depth], 1);
226
227 /* POWER4 LPAR uses 0xffff as invalid node */
228 if (nid == 0xffff || nid >= MAX_NUMNODES)
229 nid = -1;
230
231 if (nid > 0 &&
232 of_read_number(associativity, 1) >= distance_ref_points_depth) {
233 /*
234 * Skip the length field and send start of associativity array
235 */
236 initialize_distance_lookup_table(nid, associativity + 1);
237 }
238
239out:
240 return nid;
241}
242
243/* Returns the nid associated with the given device tree node,
244 * or -1 if not found.
245 */
246static int of_node_to_nid_single(struct device_node *device)
247{
248 int nid = -1;
249 const __be32 *tmp;
250
251 tmp = of_get_associativity(device);
252 if (tmp)
253 nid = associativity_to_nid(tmp);
254 return nid;
255}
256
257/* Walk the device tree upwards, looking for an associativity id */
258int of_node_to_nid(struct device_node *device)
259{
260 int nid = -1;
261
262 of_node_get(device);
263 while (device) {
264 nid = of_node_to_nid_single(device);
265 if (nid != -1)
266 break;
267
268 device = of_get_next_parent(device);
269 }
270 of_node_put(device);
271
272 return nid;
273}
274EXPORT_SYMBOL(of_node_to_nid);
275
276static int __init find_min_common_depth(void)
277{
278 int depth;
279 struct device_node *root;
280
281 if (firmware_has_feature(FW_FEATURE_OPAL))
282 root = of_find_node_by_path("/ibm,opal");
283 else
284 root = of_find_node_by_path("/rtas");
285 if (!root)
286 root = of_find_node_by_path("/");
287
288 /*
289 * This property is a set of 32-bit integers, each representing
290 * an index into the ibm,associativity nodes.
291 *
292 * With form 0 affinity the first integer is for an SMP configuration
293 * (should be all 0's) and the second is for a normal NUMA
294 * configuration. We have only one level of NUMA.
295 *
296 * With form 1 affinity the first integer is the most significant
297 * NUMA boundary and the following are progressively less significant
298 * boundaries. There can be more than one level of NUMA.
299 */
300 distance_ref_points = of_get_property(root,
301 "ibm,associativity-reference-points",
302 &distance_ref_points_depth);
303
304 if (!distance_ref_points) {
305 dbg("NUMA: ibm,associativity-reference-points not found.\n");
306 goto err;
307 }
308
309 distance_ref_points_depth /= sizeof(int);
310
311 if (firmware_has_feature(FW_FEATURE_OPAL) ||
312 firmware_has_feature(FW_FEATURE_TYPE1_AFFINITY)) {
313 dbg("Using form 1 affinity\n");
314 form1_affinity = 1;
315 }
316
317 if (form1_affinity) {
318 depth = of_read_number(distance_ref_points, 1);
319 } else {
320 if (distance_ref_points_depth < 2) {
321 printk(KERN_WARNING "NUMA: "
322 "short ibm,associativity-reference-points\n");
323 goto err;
324 }
325
326 depth = of_read_number(&distance_ref_points[1], 1);
327 }
328
329 /*
330 * Warn and cap if the hardware supports more than
331 * MAX_DISTANCE_REF_POINTS domains.
332 */
333 if (distance_ref_points_depth > MAX_DISTANCE_REF_POINTS) {
334 printk(KERN_WARNING "NUMA: distance array capped at "
335 "%d entries\n", MAX_DISTANCE_REF_POINTS);
336 distance_ref_points_depth = MAX_DISTANCE_REF_POINTS;
337 }
338
339 of_node_put(root);
340 return depth;
341
342err:
343 of_node_put(root);
344 return -1;
345}
346
347static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells)
348{
349 struct device_node *memory = NULL;
350
351 memory = of_find_node_by_type(memory, "memory");
352 if (!memory)
353 panic("numa.c: No memory nodes found!");
354
355 *n_addr_cells = of_n_addr_cells(memory);
356 *n_size_cells = of_n_size_cells(memory);
357 of_node_put(memory);
358}
359
360static unsigned long read_n_cells(int n, const __be32 **buf)
361{
362 unsigned long result = 0;
363
364 while (n--) {
365 result = (result << 32) | of_read_number(*buf, 1);
366 (*buf)++;
367 }
368 return result;
369}
370
371struct assoc_arrays {
372 u32 n_arrays;
373 u32 array_sz;
374 const __be32 *arrays;
375};
376
377/*
378 * Retrieve and validate the list of associativity arrays for drconf
379 * memory from the ibm,associativity-lookup-arrays property of the
380 * device tree..
381 *
382 * The layout of the ibm,associativity-lookup-arrays property is a number N
383 * indicating the number of associativity arrays, followed by a number M
384 * indicating the size of each associativity array, followed by a list
385 * of N associativity arrays.
386 */
387static int of_get_assoc_arrays(struct assoc_arrays *aa)
388{
389 struct device_node *memory;
390 const __be32 *prop;
391 u32 len;
392
393 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
394 if (!memory)
395 return -1;
396
397 prop = of_get_property(memory, "ibm,associativity-lookup-arrays", &len);
398 if (!prop || len < 2 * sizeof(unsigned int)) {
399 of_node_put(memory);
400 return -1;
401 }
402
403 aa->n_arrays = of_read_number(prop++, 1);
404 aa->array_sz = of_read_number(prop++, 1);
405
406 of_node_put(memory);
407
408 /* Now that we know the number of arrays and size of each array,
409 * revalidate the size of the property read in.
410 */
411 if (len < (aa->n_arrays * aa->array_sz + 2) * sizeof(unsigned int))
412 return -1;
413
414 aa->arrays = prop;
415 return 0;
416}
417
418/*
419 * This is like of_node_to_nid_single() for memory represented in the
420 * ibm,dynamic-reconfiguration-memory node.
421 */
422static int of_drconf_to_nid_single(struct drmem_lmb *lmb)
423{
424 struct assoc_arrays aa = { .arrays = NULL };
425 int default_nid = 0;
426 int nid = default_nid;
427 int rc, index;
428
429 rc = of_get_assoc_arrays(&aa);
430 if (rc)
431 return default_nid;
432
433 if (min_common_depth > 0 && min_common_depth <= aa.array_sz &&
434 !(lmb->flags & DRCONF_MEM_AI_INVALID) &&
435 lmb->aa_index < aa.n_arrays) {
436 index = lmb->aa_index * aa.array_sz + min_common_depth - 1;
437 nid = of_read_number(&aa.arrays[index], 1);
438
439 if (nid == 0xffff || nid >= MAX_NUMNODES)
440 nid = default_nid;
441
442 if (nid > 0) {
443 index = lmb->aa_index * aa.array_sz;
444 initialize_distance_lookup_table(nid,
445 &aa.arrays[index]);
446 }
447 }
448
449 return nid;
450}
451
452/*
453 * Figure out to which domain a cpu belongs and stick it there.
454 * Return the id of the domain used.
455 */
456static int numa_setup_cpu(unsigned long lcpu)
457{
458 int nid = -1;
459 struct device_node *cpu;
460
461 /*
462 * If a valid cpu-to-node mapping is already available, use it
463 * directly instead of querying the firmware, since it represents
464 * the most recent mapping notified to us by the platform (eg: VPHN).
465 */
466 if ((nid = numa_cpu_lookup_table[lcpu]) >= 0) {
467 map_cpu_to_node(lcpu, nid);
468 return nid;
469 }
470
471 cpu = of_get_cpu_node(lcpu, NULL);
472
473 if (!cpu) {
474 WARN_ON(1);
475 if (cpu_present(lcpu))
476 goto out_present;
477 else
478 goto out;
479 }
480
481 nid = of_node_to_nid_single(cpu);
482
483out_present:
484 if (nid < 0 || !node_possible(nid))
485 nid = first_online_node;
486
487 map_cpu_to_node(lcpu, nid);
488 of_node_put(cpu);
489out:
490 return nid;
491}
492
493static void verify_cpu_node_mapping(int cpu, int node)
494{
495 int base, sibling, i;
496
497 /* Verify that all the threads in the core belong to the same node */
498 base = cpu_first_thread_sibling(cpu);
499
500 for (i = 0; i < threads_per_core; i++) {
501 sibling = base + i;
502
503 if (sibling == cpu || cpu_is_offline(sibling))
504 continue;
505
506 if (cpu_to_node(sibling) != node) {
507 WARN(1, "CPU thread siblings %d and %d don't belong"
508 " to the same node!\n", cpu, sibling);
509 break;
510 }
511 }
512}
513
514/* Must run before sched domains notifier. */
515static int ppc_numa_cpu_prepare(unsigned int cpu)
516{
517 int nid;
518
519 nid = numa_setup_cpu(cpu);
520 verify_cpu_node_mapping(cpu, nid);
521 return 0;
522}
523
524static int ppc_numa_cpu_dead(unsigned int cpu)
525{
526#ifdef CONFIG_HOTPLUG_CPU
527 unmap_cpu_from_node(cpu);
528#endif
529 return 0;
530}
531
532/*
533 * Check and possibly modify a memory region to enforce the memory limit.
534 *
535 * Returns the size the region should have to enforce the memory limit.
536 * This will either be the original value of size, a truncated value,
537 * or zero. If the returned value of size is 0 the region should be
538 * discarded as it lies wholly above the memory limit.
539 */
540static unsigned long __init numa_enforce_memory_limit(unsigned long start,
541 unsigned long size)
542{
543 /*
544 * We use memblock_end_of_DRAM() in here instead of memory_limit because
545 * we've already adjusted it for the limit and it takes care of
546 * having memory holes below the limit. Also, in the case of
547 * iommu_is_off, memory_limit is not set but is implicitly enforced.
548 */
549
550 if (start + size <= memblock_end_of_DRAM())
551 return size;
552
553 if (start >= memblock_end_of_DRAM())
554 return 0;
555
556 return memblock_end_of_DRAM() - start;
557}
558
559/*
560 * Reads the counter for a given entry in
561 * linux,drconf-usable-memory property
562 */
563static inline int __init read_usm_ranges(const __be32 **usm)
564{
565 /*
566 * For each lmb in ibm,dynamic-memory a corresponding
567 * entry in linux,drconf-usable-memory property contains
568 * a counter followed by that many (base, size) duple.
569 * read the counter from linux,drconf-usable-memory
570 */
571 return read_n_cells(n_mem_size_cells, usm);
572}
573
574/*
575 * Extract NUMA information from the ibm,dynamic-reconfiguration-memory
576 * node. This assumes n_mem_{addr,size}_cells have been set.
577 */
578static void __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
579 const __be32 **usm)
580{
581 unsigned int ranges, is_kexec_kdump = 0;
582 unsigned long base, size, sz;
583 int nid;
584
585 /*
586 * Skip this block if the reserved bit is set in flags (0x80)
587 * or if the block is not assigned to this partition (0x8)
588 */
589 if ((lmb->flags & DRCONF_MEM_RESERVED)
590 || !(lmb->flags & DRCONF_MEM_ASSIGNED))
591 return;
592
593 if (*usm)
594 is_kexec_kdump = 1;
595
596 base = lmb->base_addr;
597 size = drmem_lmb_size();
598 ranges = 1;
599
600 if (is_kexec_kdump) {
601 ranges = read_usm_ranges(usm);
602 if (!ranges) /* there are no (base, size) duple */
603 return;
604 }
605
606 do {
607 if (is_kexec_kdump) {
608 base = read_n_cells(n_mem_addr_cells, usm);
609 size = read_n_cells(n_mem_size_cells, usm);
610 }
611
612 nid = of_drconf_to_nid_single(lmb);
613 fake_numa_create_new_node(((base + size) >> PAGE_SHIFT),
614 &nid);
615 node_set_online(nid);
616 sz = numa_enforce_memory_limit(base, size);
617 if (sz)
618 memblock_set_node(base, sz, &memblock.memory, nid);
619 } while (--ranges);
620}
621
622static int __init parse_numa_properties(void)
623{
624 struct device_node *memory;
625 int default_nid = 0;
626 unsigned long i;
627
628 if (numa_enabled == 0) {
629 printk(KERN_WARNING "NUMA disabled by user\n");
630 return -1;
631 }
632
633 min_common_depth = find_min_common_depth();
634
635 if (min_common_depth < 0)
636 return min_common_depth;
637
638 dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth);
639
640 /*
641 * Even though we connect cpus to numa domains later in SMP
642 * init, we need to know the node ids now. This is because
643 * each node to be onlined must have NODE_DATA etc backing it.
644 */
645 for_each_present_cpu(i) {
646 struct device_node *cpu;
647 int nid;
648
649 cpu = of_get_cpu_node(i, NULL);
650 BUG_ON(!cpu);
651 nid = of_node_to_nid_single(cpu);
652 of_node_put(cpu);
653
654 /*
655 * Don't fall back to default_nid yet -- we will plug
656 * cpus into nodes once the memory scan has discovered
657 * the topology.
658 */
659 if (nid < 0)
660 continue;
661 node_set_online(nid);
662 }
663
664 get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells);
665
666 for_each_node_by_type(memory, "memory") {
667 unsigned long start;
668 unsigned long size;
669 int nid;
670 int ranges;
671 const __be32 *memcell_buf;
672 unsigned int len;
673
674 memcell_buf = of_get_property(memory,
675 "linux,usable-memory", &len);
676 if (!memcell_buf || len <= 0)
677 memcell_buf = of_get_property(memory, "reg", &len);
678 if (!memcell_buf || len <= 0)
679 continue;
680
681 /* ranges in cell */
682 ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
683new_range:
684 /* these are order-sensitive, and modify the buffer pointer */
685 start = read_n_cells(n_mem_addr_cells, &memcell_buf);
686 size = read_n_cells(n_mem_size_cells, &memcell_buf);
687
688 /*
689 * Assumption: either all memory nodes or none will
690 * have associativity properties. If none, then
691 * everything goes to default_nid.
692 */
693 nid = of_node_to_nid_single(memory);
694 if (nid < 0)
695 nid = default_nid;
696
697 fake_numa_create_new_node(((start + size) >> PAGE_SHIFT), &nid);
698 node_set_online(nid);
699
700 size = numa_enforce_memory_limit(start, size);
701 if (size)
702 memblock_set_node(start, size, &memblock.memory, nid);
703
704 if (--ranges)
705 goto new_range;
706 }
707
708 /*
709 * Now do the same thing for each MEMBLOCK listed in the
710 * ibm,dynamic-memory property in the
711 * ibm,dynamic-reconfiguration-memory node.
712 */
713 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
714 if (memory) {
715 walk_drmem_lmbs(memory, numa_setup_drmem_lmb);
716 of_node_put(memory);
717 }
718
719 return 0;
720}
721
722static void __init setup_nonnuma(void)
723{
724 unsigned long top_of_ram = memblock_end_of_DRAM();
725 unsigned long total_ram = memblock_phys_mem_size();
726 unsigned long start_pfn, end_pfn;
727 unsigned int nid = 0;
728 struct memblock_region *reg;
729
730 printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
731 top_of_ram, total_ram);
732 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
733 (top_of_ram - total_ram) >> 20);
734
735 for_each_memblock(memory, reg) {
736 start_pfn = memblock_region_memory_base_pfn(reg);
737 end_pfn = memblock_region_memory_end_pfn(reg);
738
739 fake_numa_create_new_node(end_pfn, &nid);
740 memblock_set_node(PFN_PHYS(start_pfn),
741 PFN_PHYS(end_pfn - start_pfn),
742 &memblock.memory, nid);
743 node_set_online(nid);
744 }
745}
746
747void __init dump_numa_cpu_topology(void)
748{
749 unsigned int node;
750 unsigned int cpu, count;
751
752 if (min_common_depth == -1 || !numa_enabled)
753 return;
754
755 for_each_online_node(node) {
756 pr_info("Node %d CPUs:", node);
757
758 count = 0;
759 /*
760 * If we used a CPU iterator here we would miss printing
761 * the holes in the cpumap.
762 */
763 for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
764 if (cpumask_test_cpu(cpu,
765 node_to_cpumask_map[node])) {
766 if (count == 0)
767 pr_cont(" %u", cpu);
768 ++count;
769 } else {
770 if (count > 1)
771 pr_cont("-%u", cpu - 1);
772 count = 0;
773 }
774 }
775
776 if (count > 1)
777 pr_cont("-%u", nr_cpu_ids - 1);
778 pr_cont("\n");
779 }
780}
781
782/* Initialize NODE_DATA for a node on the local memory */
783static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
784{
785 u64 spanned_pages = end_pfn - start_pfn;
786 const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
787 u64 nd_pa;
788 void *nd;
789 int tnid;
790
791 nd_pa = memblock_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
792 nd = __va(nd_pa);
793
794 /* report and initialize */
795 pr_info(" NODE_DATA [mem %#010Lx-%#010Lx]\n",
796 nd_pa, nd_pa + nd_size - 1);
797 tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
798 if (tnid != nid)
799 pr_info(" NODE_DATA(%d) on node %d\n", nid, tnid);
800
801 node_data[nid] = nd;
802 memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
803 NODE_DATA(nid)->node_id = nid;
804 NODE_DATA(nid)->node_start_pfn = start_pfn;
805 NODE_DATA(nid)->node_spanned_pages = spanned_pages;
806}
807
808static void __init find_possible_nodes(void)
809{
810 struct device_node *rtas;
811 u32 numnodes, i;
812
813 if (min_common_depth <= 0)
814 return;
815
816 rtas = of_find_node_by_path("/rtas");
817 if (!rtas)
818 return;
819
820 if (of_property_read_u32_index(rtas,
821 "ibm,max-associativity-domains",
822 min_common_depth, &numnodes))
823 goto out;
824
825 for (i = 0; i < numnodes; i++) {
826 if (!node_possible(i))
827 node_set(i, node_possible_map);
828 }
829
830out:
831 of_node_put(rtas);
832}
833
834void __init mem_topology_setup(void)
835{
836 int cpu;
837
838 if (parse_numa_properties())
839 setup_nonnuma();
840
841 /*
842 * Modify the set of possible NUMA nodes to reflect information
843 * available about the set of online nodes, and the set of nodes
844 * that we expect to make use of for this platform's affinity
845 * calculations.
846 */
847 nodes_and(node_possible_map, node_possible_map, node_online_map);
848
849 find_possible_nodes();
850
851 setup_node_to_cpumask_map();
852
853 reset_numa_cpu_lookup_table();
854
855 for_each_present_cpu(cpu)
856 numa_setup_cpu(cpu);
857}
858
859void __init initmem_init(void)
860{
861 int nid;
862
863 max_low_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
864 max_pfn = max_low_pfn;
865
866 memblock_dump_all();
867
868 for_each_online_node(nid) {
869 unsigned long start_pfn, end_pfn;
870
871 get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
872 setup_node_data(nid, start_pfn, end_pfn);
873 sparse_memory_present_with_active_regions(nid);
874 }
875
876 sparse_init();
877
878 /*
879 * We need the numa_cpu_lookup_table to be accurate for all CPUs,
880 * even before we online them, so that we can use cpu_to_{node,mem}
881 * early in boot, cf. smp_prepare_cpus().
882 * _nocalls() + manual invocation is used because cpuhp is not yet
883 * initialized for the boot CPU.
884 */
885 cpuhp_setup_state_nocalls(CPUHP_POWER_NUMA_PREPARE, "powerpc/numa:prepare",
886 ppc_numa_cpu_prepare, ppc_numa_cpu_dead);
887}
888
889static int __init early_numa(char *p)
890{
891 if (!p)
892 return 0;
893
894 if (strstr(p, "off"))
895 numa_enabled = 0;
896
897 if (strstr(p, "debug"))
898 numa_debug = 1;
899
900 p = strstr(p, "fake=");
901 if (p)
902 cmdline = p + strlen("fake=");
903
904 return 0;
905}
906early_param("numa", early_numa);
907
908static bool topology_updates_enabled = true;
909
910static int __init early_topology_updates(char *p)
911{
912 if (!p)
913 return 0;
914
915 if (!strcmp(p, "off")) {
916 pr_info("Disabling topology updates\n");
917 topology_updates_enabled = false;
918 }
919
920 return 0;
921}
922early_param("topology_updates", early_topology_updates);
923
924#ifdef CONFIG_MEMORY_HOTPLUG
925/*
926 * Find the node associated with a hot added memory section for
927 * memory represented in the device tree by the property
928 * ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory.
929 */
930static int hot_add_drconf_scn_to_nid(unsigned long scn_addr)
931{
932 struct drmem_lmb *lmb;
933 unsigned long lmb_size;
934 int nid = -1;
935
936 lmb_size = drmem_lmb_size();
937
938 for_each_drmem_lmb(lmb) {
939 /* skip this block if it is reserved or not assigned to
940 * this partition */
941 if ((lmb->flags & DRCONF_MEM_RESERVED)
942 || !(lmb->flags & DRCONF_MEM_ASSIGNED))
943 continue;
944
945 if ((scn_addr < lmb->base_addr)
946 || (scn_addr >= (lmb->base_addr + lmb_size)))
947 continue;
948
949 nid = of_drconf_to_nid_single(lmb);
950 break;
951 }
952
953 return nid;
954}
955
956/*
957 * Find the node associated with a hot added memory section for memory
958 * represented in the device tree as a node (i.e. memory@XXXX) for
959 * each memblock.
960 */
961static int hot_add_node_scn_to_nid(unsigned long scn_addr)
962{
963 struct device_node *memory;
964 int nid = -1;
965
966 for_each_node_by_type(memory, "memory") {
967 unsigned long start, size;
968 int ranges;
969 const __be32 *memcell_buf;
970 unsigned int len;
971
972 memcell_buf = of_get_property(memory, "reg", &len);
973 if (!memcell_buf || len <= 0)
974 continue;
975
976 /* ranges in cell */
977 ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
978
979 while (ranges--) {
980 start = read_n_cells(n_mem_addr_cells, &memcell_buf);
981 size = read_n_cells(n_mem_size_cells, &memcell_buf);
982
983 if ((scn_addr < start) || (scn_addr >= (start + size)))
984 continue;
985
986 nid = of_node_to_nid_single(memory);
987 break;
988 }
989
990 if (nid >= 0)
991 break;
992 }
993
994 of_node_put(memory);
995
996 return nid;
997}
998
999/*
1000 * Find the node associated with a hot added memory section. Section
1001 * corresponds to a SPARSEMEM section, not an MEMBLOCK. It is assumed that
1002 * sections are fully contained within a single MEMBLOCK.
1003 */
1004int hot_add_scn_to_nid(unsigned long scn_addr)
1005{
1006 struct device_node *memory = NULL;
1007 int nid;
1008
1009 if (!numa_enabled || (min_common_depth < 0))
1010 return first_online_node;
1011
1012 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1013 if (memory) {
1014 nid = hot_add_drconf_scn_to_nid(scn_addr);
1015 of_node_put(memory);
1016 } else {
1017 nid = hot_add_node_scn_to_nid(scn_addr);
1018 }
1019
1020 if (nid < 0 || !node_possible(nid))
1021 nid = first_online_node;
1022
1023 return nid;
1024}
1025
1026static u64 hot_add_drconf_memory_max(void)
1027{
1028 struct device_node *memory = NULL;
1029 struct device_node *dn = NULL;
1030 const __be64 *lrdr = NULL;
1031
1032 dn = of_find_node_by_path("/rtas");
1033 if (dn) {
1034 lrdr = of_get_property(dn, "ibm,lrdr-capacity", NULL);
1035 of_node_put(dn);
1036 if (lrdr)
1037 return be64_to_cpup(lrdr);
1038 }
1039
1040 memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1041 if (memory) {
1042 of_node_put(memory);
1043 return drmem_lmb_memory_max();
1044 }
1045 return 0;
1046}
1047
1048/*
1049 * memory_hotplug_max - return max address of memory that may be added
1050 *
1051 * This is currently only used on systems that support drconfig memory
1052 * hotplug.
1053 */
1054u64 memory_hotplug_max(void)
1055{
1056 return max(hot_add_drconf_memory_max(), memblock_end_of_DRAM());
1057}
1058#endif /* CONFIG_MEMORY_HOTPLUG */
1059
1060/* Virtual Processor Home Node (VPHN) support */
1061#ifdef CONFIG_PPC_SPLPAR
1062
1063#include "vphn.h"
1064
1065struct topology_update_data {
1066 struct topology_update_data *next;
1067 unsigned int cpu;
1068 int old_nid;
1069 int new_nid;
1070};
1071
1072#define TOPOLOGY_DEF_TIMER_SECS 60
1073
1074static u8 vphn_cpu_change_counts[NR_CPUS][MAX_DISTANCE_REF_POINTS];
1075static cpumask_t cpu_associativity_changes_mask;
1076static int vphn_enabled;
1077static int prrn_enabled;
1078static void reset_topology_timer(void);
1079static int topology_timer_secs = 1;
1080static int topology_inited;
1081static int topology_update_needed;
1082
1083/*
1084 * Change polling interval for associativity changes.
1085 */
1086int timed_topology_update(int nsecs)
1087{
1088 if (vphn_enabled) {
1089 if (nsecs > 0)
1090 topology_timer_secs = nsecs;
1091 else
1092 topology_timer_secs = TOPOLOGY_DEF_TIMER_SECS;
1093
1094 reset_topology_timer();
1095 }
1096
1097 return 0;
1098}
1099
1100/*
1101 * Store the current values of the associativity change counters in the
1102 * hypervisor.
1103 */
1104static void setup_cpu_associativity_change_counters(void)
1105{
1106 int cpu;
1107
1108 /* The VPHN feature supports a maximum of 8 reference points */
1109 BUILD_BUG_ON(MAX_DISTANCE_REF_POINTS > 8);
1110
1111 for_each_possible_cpu(cpu) {
1112 int i;
1113 u8 *counts = vphn_cpu_change_counts[cpu];
1114 volatile u8 *hypervisor_counts = lppaca_of(cpu).vphn_assoc_counts;
1115
1116 for (i = 0; i < distance_ref_points_depth; i++)
1117 counts[i] = hypervisor_counts[i];
1118 }
1119}
1120
1121/*
1122 * The hypervisor maintains a set of 8 associativity change counters in
1123 * the VPA of each cpu that correspond to the associativity levels in the
1124 * ibm,associativity-reference-points property. When an associativity
1125 * level changes, the corresponding counter is incremented.
1126 *
1127 * Set a bit in cpu_associativity_changes_mask for each cpu whose home
1128 * node associativity levels have changed.
1129 *
1130 * Returns the number of cpus with unhandled associativity changes.
1131 */
1132static int update_cpu_associativity_changes_mask(void)
1133{
1134 int cpu;
1135 cpumask_t *changes = &cpu_associativity_changes_mask;
1136
1137 for_each_possible_cpu(cpu) {
1138 int i, changed = 0;
1139 u8 *counts = vphn_cpu_change_counts[cpu];
1140 volatile u8 *hypervisor_counts = lppaca_of(cpu).vphn_assoc_counts;
1141
1142 for (i = 0; i < distance_ref_points_depth; i++) {
1143 if (hypervisor_counts[i] != counts[i]) {
1144 counts[i] = hypervisor_counts[i];
1145 changed = 1;
1146 }
1147 }
1148 if (changed) {
1149 cpumask_or(changes, changes, cpu_sibling_mask(cpu));
1150 cpu = cpu_last_thread_sibling(cpu);
1151 }
1152 }
1153
1154 return cpumask_weight(changes);
1155}
1156
1157/*
1158 * Retrieve the new associativity information for a virtual processor's
1159 * home node.
1160 */
1161static long hcall_vphn(unsigned long cpu, __be32 *associativity)
1162{
1163 long rc;
1164 long retbuf[PLPAR_HCALL9_BUFSIZE] = {0};
1165 u64 flags = 1;
1166 int hwcpu = get_hard_smp_processor_id(cpu);
1167
1168 rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, retbuf, flags, hwcpu);
1169 vphn_unpack_associativity(retbuf, associativity);
1170
1171 return rc;
1172}
1173
1174static long vphn_get_associativity(unsigned long cpu,
1175 __be32 *associativity)
1176{
1177 long rc;
1178
1179 rc = hcall_vphn(cpu, associativity);
1180
1181 switch (rc) {
1182 case H_FUNCTION:
1183 printk(KERN_INFO
1184 "VPHN is not supported. Disabling polling...\n");
1185 stop_topology_update();
1186 break;
1187 case H_HARDWARE:
1188 printk(KERN_ERR
1189 "hcall_vphn() experienced a hardware fault "
1190 "preventing VPHN. Disabling polling...\n");
1191 stop_topology_update();
1192 break;
1193 case H_SUCCESS:
1194 dbg("VPHN hcall succeeded. Reset polling...\n");
1195 timed_topology_update(0);
1196 break;
1197 }
1198
1199 return rc;
1200}
1201
1202int find_and_online_cpu_nid(int cpu)
1203{
1204 __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
1205 int new_nid;
1206
1207 /* Use associativity from first thread for all siblings */
1208 vphn_get_associativity(cpu, associativity);
1209 new_nid = associativity_to_nid(associativity);
1210 if (new_nid < 0 || !node_possible(new_nid))
1211 new_nid = first_online_node;
1212
1213 if (NODE_DATA(new_nid) == NULL) {
1214#ifdef CONFIG_MEMORY_HOTPLUG
1215 /*
1216 * Need to ensure that NODE_DATA is initialized for a node from
1217 * available memory (see memblock_alloc_try_nid). If unable to
1218 * init the node, then default to nearest node that has memory
1219 * installed.
1220 */
1221 if (try_online_node(new_nid))
1222 new_nid = first_online_node;
1223#else
1224 /*
1225 * Default to using the nearest node that has memory installed.
1226 * Otherwise, it would be necessary to patch the kernel MM code
1227 * to deal with more memoryless-node error conditions.
1228 */
1229 new_nid = first_online_node;
1230#endif
1231 }
1232
1233 pr_debug("%s:%d cpu %d nid %d\n", __FUNCTION__, __LINE__,
1234 cpu, new_nid);
1235 return new_nid;
1236}
1237
1238/*
1239 * Update the CPU maps and sysfs entries for a single CPU when its NUMA
1240 * characteristics change. This function doesn't perform any locking and is
1241 * only safe to call from stop_machine().
1242 */
1243static int update_cpu_topology(void *data)
1244{
1245 struct topology_update_data *update;
1246 unsigned long cpu;
1247
1248 if (!data)
1249 return -EINVAL;
1250
1251 cpu = smp_processor_id();
1252
1253 for (update = data; update; update = update->next) {
1254 int new_nid = update->new_nid;
1255 if (cpu != update->cpu)
1256 continue;
1257
1258 unmap_cpu_from_node(cpu);
1259 map_cpu_to_node(cpu, new_nid);
1260 set_cpu_numa_node(cpu, new_nid);
1261 set_cpu_numa_mem(cpu, local_memory_node(new_nid));
1262 vdso_getcpu_init();
1263 }
1264
1265 return 0;
1266}
1267
1268static int update_lookup_table(void *data)
1269{
1270 struct topology_update_data *update;
1271
1272 if (!data)
1273 return -EINVAL;
1274
1275 /*
1276 * Upon topology update, the numa-cpu lookup table needs to be updated
1277 * for all threads in the core, including offline CPUs, to ensure that
1278 * future hotplug operations respect the cpu-to-node associativity
1279 * properly.
1280 */
1281 for (update = data; update; update = update->next) {
1282 int nid, base, j;
1283
1284 nid = update->new_nid;
1285 base = cpu_first_thread_sibling(update->cpu);
1286
1287 for (j = 0; j < threads_per_core; j++) {
1288 update_numa_cpu_lookup_table(base + j, nid);
1289 }
1290 }
1291
1292 return 0;
1293}
1294
1295/*
1296 * Update the node maps and sysfs entries for each cpu whose home node
1297 * has changed. Returns 1 when the topology has changed, and 0 otherwise.
1298 *
1299 * cpus_locked says whether we already hold cpu_hotplug_lock.
1300 */
1301int numa_update_cpu_topology(bool cpus_locked)
1302{
1303 unsigned int cpu, sibling, changed = 0;
1304 struct topology_update_data *updates, *ud;
1305 cpumask_t updated_cpus;
1306 struct device *dev;
1307 int weight, new_nid, i = 0;
1308
1309 if (!prrn_enabled && !vphn_enabled) {
1310 if (!topology_inited)
1311 topology_update_needed = 1;
1312 return 0;
1313 }
1314
1315 weight = cpumask_weight(&cpu_associativity_changes_mask);
1316 if (!weight)
1317 return 0;
1318
1319 updates = kzalloc(weight * (sizeof(*updates)), GFP_KERNEL);
1320 if (!updates)
1321 return 0;
1322
1323 cpumask_clear(&updated_cpus);
1324
1325 for_each_cpu(cpu, &cpu_associativity_changes_mask) {
1326 /*
1327 * If siblings aren't flagged for changes, updates list
1328 * will be too short. Skip on this update and set for next
1329 * update.
1330 */
1331 if (!cpumask_subset(cpu_sibling_mask(cpu),
1332 &cpu_associativity_changes_mask)) {
1333 pr_info("Sibling bits not set for associativity "
1334 "change, cpu%d\n", cpu);
1335 cpumask_or(&cpu_associativity_changes_mask,
1336 &cpu_associativity_changes_mask,
1337 cpu_sibling_mask(cpu));
1338 cpu = cpu_last_thread_sibling(cpu);
1339 continue;
1340 }
1341
1342 new_nid = find_and_online_cpu_nid(cpu);
1343
1344 if (new_nid == numa_cpu_lookup_table[cpu]) {
1345 cpumask_andnot(&cpu_associativity_changes_mask,
1346 &cpu_associativity_changes_mask,
1347 cpu_sibling_mask(cpu));
1348 dbg("Assoc chg gives same node %d for cpu%d\n",
1349 new_nid, cpu);
1350 cpu = cpu_last_thread_sibling(cpu);
1351 continue;
1352 }
1353
1354 for_each_cpu(sibling, cpu_sibling_mask(cpu)) {
1355 ud = &updates[i++];
1356 ud->next = &updates[i];
1357 ud->cpu = sibling;
1358 ud->new_nid = new_nid;
1359 ud->old_nid = numa_cpu_lookup_table[sibling];
1360 cpumask_set_cpu(sibling, &updated_cpus);
1361 }
1362 cpu = cpu_last_thread_sibling(cpu);
1363 }
1364
1365 /*
1366 * Prevent processing of 'updates' from overflowing array
1367 * where last entry filled in a 'next' pointer.
1368 */
1369 if (i)
1370 updates[i-1].next = NULL;
1371
1372 pr_debug("Topology update for the following CPUs:\n");
1373 if (cpumask_weight(&updated_cpus)) {
1374 for (ud = &updates[0]; ud; ud = ud->next) {
1375 pr_debug("cpu %d moving from node %d "
1376 "to %d\n", ud->cpu,
1377 ud->old_nid, ud->new_nid);
1378 }
1379 }
1380
1381 /*
1382 * In cases where we have nothing to update (because the updates list
1383 * is too short or because the new topology is same as the old one),
1384 * skip invoking update_cpu_topology() via stop-machine(). This is
1385 * necessary (and not just a fast-path optimization) since stop-machine
1386 * can end up electing a random CPU to run update_cpu_topology(), and
1387 * thus trick us into setting up incorrect cpu-node mappings (since
1388 * 'updates' is kzalloc()'ed).
1389 *
1390 * And for the similar reason, we will skip all the following updating.
1391 */
1392 if (!cpumask_weight(&updated_cpus))
1393 goto out;
1394
1395 if (cpus_locked)
1396 stop_machine_cpuslocked(update_cpu_topology, &updates[0],
1397 &updated_cpus);
1398 else
1399 stop_machine(update_cpu_topology, &updates[0], &updated_cpus);
1400
1401 /*
1402 * Update the numa-cpu lookup table with the new mappings, even for
1403 * offline CPUs. It is best to perform this update from the stop-
1404 * machine context.
1405 */
1406 if (cpus_locked)
1407 stop_machine_cpuslocked(update_lookup_table, &updates[0],
1408 cpumask_of(raw_smp_processor_id()));
1409 else
1410 stop_machine(update_lookup_table, &updates[0],
1411 cpumask_of(raw_smp_processor_id()));
1412
1413 for (ud = &updates[0]; ud; ud = ud->next) {
1414 unregister_cpu_under_node(ud->cpu, ud->old_nid);
1415 register_cpu_under_node(ud->cpu, ud->new_nid);
1416
1417 dev = get_cpu_device(ud->cpu);
1418 if (dev)
1419 kobject_uevent(&dev->kobj, KOBJ_CHANGE);
1420 cpumask_clear_cpu(ud->cpu, &cpu_associativity_changes_mask);
1421 changed = 1;
1422 }
1423
1424out:
1425 kfree(updates);
1426 topology_update_needed = 0;
1427 return changed;
1428}
1429
1430int arch_update_cpu_topology(void)
1431{
1432 return numa_update_cpu_topology(true);
1433}
1434
1435static void topology_work_fn(struct work_struct *work)
1436{
1437 rebuild_sched_domains();
1438}
1439static DECLARE_WORK(topology_work, topology_work_fn);
1440
1441static void topology_schedule_update(void)
1442{
1443 schedule_work(&topology_work);
1444}
1445
1446static void topology_timer_fn(struct timer_list *unused)
1447{
1448 if (prrn_enabled && cpumask_weight(&cpu_associativity_changes_mask))
1449 topology_schedule_update();
1450 else if (vphn_enabled) {
1451 if (update_cpu_associativity_changes_mask() > 0)
1452 topology_schedule_update();
1453 reset_topology_timer();
1454 }
1455}
1456static struct timer_list topology_timer;
1457
1458static void reset_topology_timer(void)
1459{
1460 mod_timer(&topology_timer, jiffies + topology_timer_secs * HZ);
1461}
1462
1463#ifdef CONFIG_SMP
1464
1465static void stage_topology_update(int core_id)
1466{
1467 cpumask_or(&cpu_associativity_changes_mask,
1468 &cpu_associativity_changes_mask, cpu_sibling_mask(core_id));
1469 reset_topology_timer();
1470}
1471
1472static int dt_update_callback(struct notifier_block *nb,
1473 unsigned long action, void *data)
1474{
1475 struct of_reconfig_data *update = data;
1476 int rc = NOTIFY_DONE;
1477
1478 switch (action) {
1479 case OF_RECONFIG_UPDATE_PROPERTY:
1480 if (!of_prop_cmp(update->dn->type, "cpu") &&
1481 !of_prop_cmp(update->prop->name, "ibm,associativity")) {
1482 u32 core_id;
1483 of_property_read_u32(update->dn, "reg", &core_id);
1484 stage_topology_update(core_id);
1485 rc = NOTIFY_OK;
1486 }
1487 break;
1488 }
1489
1490 return rc;
1491}
1492
1493static struct notifier_block dt_update_nb = {
1494 .notifier_call = dt_update_callback,
1495};
1496
1497#endif
1498
1499/*
1500 * Start polling for associativity changes.
1501 */
1502int start_topology_update(void)
1503{
1504 int rc = 0;
1505
1506 if (firmware_has_feature(FW_FEATURE_PRRN)) {
1507 if (!prrn_enabled) {
1508 prrn_enabled = 1;
1509#ifdef CONFIG_SMP
1510 rc = of_reconfig_notifier_register(&dt_update_nb);
1511#endif
1512 }
1513 }
1514 if (firmware_has_feature(FW_FEATURE_VPHN) &&
1515 lppaca_shared_proc(get_lppaca())) {
1516 if (!vphn_enabled) {
1517 vphn_enabled = 1;
1518 setup_cpu_associativity_change_counters();
1519 timer_setup(&topology_timer, topology_timer_fn,
1520 TIMER_DEFERRABLE);
1521 reset_topology_timer();
1522 }
1523 }
1524
1525 return rc;
1526}
1527
1528/*
1529 * Disable polling for VPHN associativity changes.
1530 */
1531int stop_topology_update(void)
1532{
1533 int rc = 0;
1534
1535 if (prrn_enabled) {
1536 prrn_enabled = 0;
1537#ifdef CONFIG_SMP
1538 rc = of_reconfig_notifier_unregister(&dt_update_nb);
1539#endif
1540 }
1541 if (vphn_enabled) {
1542 vphn_enabled = 0;
1543 rc = del_timer_sync(&topology_timer);
1544 }
1545
1546 return rc;
1547}
1548
1549int prrn_is_enabled(void)
1550{
1551 return prrn_enabled;
1552}
1553
1554static int topology_read(struct seq_file *file, void *v)
1555{
1556 if (vphn_enabled || prrn_enabled)
1557 seq_puts(file, "on\n");
1558 else
1559 seq_puts(file, "off\n");
1560
1561 return 0;
1562}
1563
1564static int topology_open(struct inode *inode, struct file *file)
1565{
1566 return single_open(file, topology_read, NULL);
1567}
1568
1569static ssize_t topology_write(struct file *file, const char __user *buf,
1570 size_t count, loff_t *off)
1571{
1572 char kbuf[4]; /* "on" or "off" plus null. */
1573 int read_len;
1574
1575 read_len = count < 3 ? count : 3;
1576 if (copy_from_user(kbuf, buf, read_len))
1577 return -EINVAL;
1578
1579 kbuf[read_len] = '\0';
1580
1581 if (!strncmp(kbuf, "on", 2))
1582 start_topology_update();
1583 else if (!strncmp(kbuf, "off", 3))
1584 stop_topology_update();
1585 else
1586 return -EINVAL;
1587
1588 return count;
1589}
1590
1591static const struct file_operations topology_ops = {
1592 .read = seq_read,
1593 .write = topology_write,
1594 .open = topology_open,
1595 .release = single_release
1596};
1597
1598static int topology_update_init(void)
1599{
1600 /* Do not poll for changes if disabled at boot */
1601 if (topology_updates_enabled)
1602 start_topology_update();
1603
1604 if (vphn_enabled)
1605 topology_schedule_update();
1606
1607 if (!proc_create("powerpc/topology_updates", 0644, NULL, &topology_ops))
1608 return -ENOMEM;
1609
1610 topology_inited = 1;
1611 if (topology_update_needed)
1612 bitmap_fill(cpumask_bits(&cpu_associativity_changes_mask),
1613 nr_cpumask_bits);
1614
1615 return 0;
1616}
1617device_initcall(topology_update_init);
1618#endif /* CONFIG_PPC_SPLPAR */