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-rw-r--r--kernel/cpu.c145
1 files changed, 100 insertions, 45 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 8ea32e8d68b..47fff3b63cb 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -15,29 +15,8 @@
15#include <linux/stop_machine.h> 15#include <linux/stop_machine.h>
16#include <linux/mutex.h> 16#include <linux/mutex.h>
17 17
18/* 18#ifdef CONFIG_SMP
19 * Represents all cpu's present in the system 19/* Serializes the updates to cpu_online_mask, cpu_present_mask */
20 * In systems capable of hotplug, this map could dynamically grow
21 * as new cpu's are detected in the system via any platform specific
22 * method, such as ACPI for e.g.
23 */
24cpumask_t cpu_present_map __read_mostly;
25EXPORT_SYMBOL(cpu_present_map);
26
27#ifndef CONFIG_SMP
28
29/*
30 * Represents all cpu's that are currently online.
31 */
32cpumask_t cpu_online_map __read_mostly = CPU_MASK_ALL;
33EXPORT_SYMBOL(cpu_online_map);
34
35cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL;
36EXPORT_SYMBOL(cpu_possible_map);
37
38#else /* CONFIG_SMP */
39
40/* Serializes the updates to cpu_online_map, cpu_present_map */
41static DEFINE_MUTEX(cpu_add_remove_lock); 20static DEFINE_MUTEX(cpu_add_remove_lock);
42 21
43static __cpuinitdata RAW_NOTIFIER_HEAD(cpu_chain); 22static __cpuinitdata RAW_NOTIFIER_HEAD(cpu_chain);
@@ -64,8 +43,6 @@ void __init cpu_hotplug_init(void)
64 cpu_hotplug.refcount = 0; 43 cpu_hotplug.refcount = 0;
65} 44}
66 45
67cpumask_t cpu_active_map;
68
69#ifdef CONFIG_HOTPLUG_CPU 46#ifdef CONFIG_HOTPLUG_CPU
70 47
71void get_online_cpus(void) 48void get_online_cpus(void)
@@ -96,7 +73,7 @@ EXPORT_SYMBOL_GPL(put_online_cpus);
96 73
97/* 74/*
98 * The following two API's must be used when attempting 75 * The following two API's must be used when attempting
99 * to serialize the updates to cpu_online_map, cpu_present_map. 76 * to serialize the updates to cpu_online_mask, cpu_present_mask.
100 */ 77 */
101void cpu_maps_update_begin(void) 78void cpu_maps_update_begin(void)
102{ 79{
@@ -217,7 +194,7 @@ static int __ref take_cpu_down(void *_param)
217static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) 194static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
218{ 195{
219 int err, nr_calls = 0; 196 int err, nr_calls = 0;
220 cpumask_t old_allowed, tmp; 197 cpumask_var_t old_allowed;
221 void *hcpu = (void *)(long)cpu; 198 void *hcpu = (void *)(long)cpu;
222 unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; 199 unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
223 struct take_cpu_down_param tcd_param = { 200 struct take_cpu_down_param tcd_param = {
@@ -231,6 +208,9 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
231 if (!cpu_online(cpu)) 208 if (!cpu_online(cpu))
232 return -EINVAL; 209 return -EINVAL;
233 210
211 if (!alloc_cpumask_var(&old_allowed, GFP_KERNEL))
212 return -ENOMEM;
213
234 cpu_hotplug_begin(); 214 cpu_hotplug_begin();
235 err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod, 215 err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod,
236 hcpu, -1, &nr_calls); 216 hcpu, -1, &nr_calls);
@@ -245,13 +225,11 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
245 } 225 }
246 226
247 /* Ensure that we are not runnable on dying cpu */ 227 /* Ensure that we are not runnable on dying cpu */
248 old_allowed = current->cpus_allowed; 228 cpumask_copy(old_allowed, &current->cpus_allowed);
249 cpus_setall(tmp); 229 set_cpus_allowed_ptr(current,
250 cpu_clear(cpu, tmp); 230 cpumask_of(cpumask_any_but(cpu_online_mask, cpu)));
251 set_cpus_allowed_ptr(current, &tmp);
252 tmp = cpumask_of_cpu(cpu);
253 231
254 err = __stop_machine(take_cpu_down, &tcd_param, &tmp); 232 err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu));
255 if (err) { 233 if (err) {
256 /* CPU didn't die: tell everyone. Can't complain. */ 234 /* CPU didn't die: tell everyone. Can't complain. */
257 if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod, 235 if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
@@ -277,7 +255,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
277 check_for_tasks(cpu); 255 check_for_tasks(cpu);
278 256
279out_allowed: 257out_allowed:
280 set_cpus_allowed_ptr(current, &old_allowed); 258 set_cpus_allowed_ptr(current, old_allowed);
281out_release: 259out_release:
282 cpu_hotplug_done(); 260 cpu_hotplug_done();
283 if (!err) { 261 if (!err) {
@@ -285,6 +263,7 @@ out_release:
285 hcpu) == NOTIFY_BAD) 263 hcpu) == NOTIFY_BAD)
286 BUG(); 264 BUG();
287 } 265 }
266 free_cpumask_var(old_allowed);
288 return err; 267 return err;
289} 268}
290 269
@@ -303,7 +282,7 @@ int __ref cpu_down(unsigned int cpu)
303 282
304 /* 283 /*
305 * Make sure the all cpus did the reschedule and are not 284 * Make sure the all cpus did the reschedule and are not
306 * using stale version of the cpu_active_map. 285 * using stale version of the cpu_active_mask.
307 * This is not strictly necessary becuase stop_machine() 286 * This is not strictly necessary becuase stop_machine()
308 * that we run down the line already provides the required 287 * that we run down the line already provides the required
309 * synchronization. But it's really a side effect and we do not 288 * synchronization. But it's really a side effect and we do not
@@ -367,7 +346,7 @@ out_notify:
367int __cpuinit cpu_up(unsigned int cpu) 346int __cpuinit cpu_up(unsigned int cpu)
368{ 347{
369 int err = 0; 348 int err = 0;
370 if (!cpu_isset(cpu, cpu_possible_map)) { 349 if (!cpu_possible(cpu)) {
371 printk(KERN_ERR "can't online cpu %d because it is not " 350 printk(KERN_ERR "can't online cpu %d because it is not "
372 "configured as may-hotadd at boot time\n", cpu); 351 "configured as may-hotadd at boot time\n", cpu);
373#if defined(CONFIG_IA64) || defined(CONFIG_X86_64) 352#if defined(CONFIG_IA64) || defined(CONFIG_X86_64)
@@ -392,25 +371,25 @@ out:
392} 371}
393 372
394#ifdef CONFIG_PM_SLEEP_SMP 373#ifdef CONFIG_PM_SLEEP_SMP
395static cpumask_t frozen_cpus; 374static cpumask_var_t frozen_cpus;
396 375
397int disable_nonboot_cpus(void) 376int disable_nonboot_cpus(void)
398{ 377{
399 int cpu, first_cpu, error = 0; 378 int cpu, first_cpu, error = 0;
400 379
401 cpu_maps_update_begin(); 380 cpu_maps_update_begin();
402 first_cpu = first_cpu(cpu_online_map); 381 first_cpu = cpumask_first(cpu_online_mask);
403 /* We take down all of the non-boot CPUs in one shot to avoid races 382 /* We take down all of the non-boot CPUs in one shot to avoid races
404 * with the userspace trying to use the CPU hotplug at the same time 383 * with the userspace trying to use the CPU hotplug at the same time
405 */ 384 */
406 cpus_clear(frozen_cpus); 385 cpumask_clear(frozen_cpus);
407 printk("Disabling non-boot CPUs ...\n"); 386 printk("Disabling non-boot CPUs ...\n");
408 for_each_online_cpu(cpu) { 387 for_each_online_cpu(cpu) {
409 if (cpu == first_cpu) 388 if (cpu == first_cpu)
410 continue; 389 continue;
411 error = _cpu_down(cpu, 1); 390 error = _cpu_down(cpu, 1);
412 if (!error) { 391 if (!error) {
413 cpu_set(cpu, frozen_cpus); 392 cpumask_set_cpu(cpu, frozen_cpus);
414 printk("CPU%d is down\n", cpu); 393 printk("CPU%d is down\n", cpu);
415 } else { 394 } else {
416 printk(KERN_ERR "Error taking CPU%d down: %d\n", 395 printk(KERN_ERR "Error taking CPU%d down: %d\n",
@@ -436,11 +415,11 @@ void __ref enable_nonboot_cpus(void)
436 /* Allow everyone to use the CPU hotplug again */ 415 /* Allow everyone to use the CPU hotplug again */
437 cpu_maps_update_begin(); 416 cpu_maps_update_begin();
438 cpu_hotplug_disabled = 0; 417 cpu_hotplug_disabled = 0;
439 if (cpus_empty(frozen_cpus)) 418 if (cpumask_empty(frozen_cpus))
440 goto out; 419 goto out;
441 420
442 printk("Enabling non-boot CPUs ...\n"); 421 printk("Enabling non-boot CPUs ...\n");
443 for_each_cpu_mask_nr(cpu, frozen_cpus) { 422 for_each_cpu(cpu, frozen_cpus) {
444 error = _cpu_up(cpu, 1); 423 error = _cpu_up(cpu, 1);
445 if (!error) { 424 if (!error) {
446 printk("CPU%d is up\n", cpu); 425 printk("CPU%d is up\n", cpu);
@@ -448,10 +427,18 @@ void __ref enable_nonboot_cpus(void)
448 } 427 }
449 printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error); 428 printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error);
450 } 429 }
451 cpus_clear(frozen_cpus); 430 cpumask_clear(frozen_cpus);
452out: 431out:
453 cpu_maps_update_done(); 432 cpu_maps_update_done();
454} 433}
434
435static int alloc_frozen_cpus(void)
436{
437 if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO))
438 return -ENOMEM;
439 return 0;
440}
441core_initcall(alloc_frozen_cpus);
455#endif /* CONFIG_PM_SLEEP_SMP */ 442#endif /* CONFIG_PM_SLEEP_SMP */
456 443
457/** 444/**
@@ -467,7 +454,7 @@ void __cpuinit notify_cpu_starting(unsigned int cpu)
467 unsigned long val = CPU_STARTING; 454 unsigned long val = CPU_STARTING;
468 455
469#ifdef CONFIG_PM_SLEEP_SMP 456#ifdef CONFIG_PM_SLEEP_SMP
470 if (cpu_isset(cpu, frozen_cpus)) 457 if (frozen_cpus != NULL && cpumask_test_cpu(cpu, frozen_cpus))
471 val = CPU_STARTING_FROZEN; 458 val = CPU_STARTING_FROZEN;
472#endif /* CONFIG_PM_SLEEP_SMP */ 459#endif /* CONFIG_PM_SLEEP_SMP */
473 raw_notifier_call_chain(&cpu_chain, val, (void *)(long)cpu); 460 raw_notifier_call_chain(&cpu_chain, val, (void *)(long)cpu);
@@ -479,7 +466,7 @@ void __cpuinit notify_cpu_starting(unsigned int cpu)
479 * cpu_bit_bitmap[] is a special, "compressed" data structure that 466 * cpu_bit_bitmap[] is a special, "compressed" data structure that
480 * represents all NR_CPUS bits binary values of 1<<nr. 467 * represents all NR_CPUS bits binary values of 1<<nr.
481 * 468 *
482 * It is used by cpumask_of_cpu() to get a constant address to a CPU 469 * It is used by cpumask_of() to get a constant address to a CPU
483 * mask value that has a single bit set only. 470 * mask value that has a single bit set only.
484 */ 471 */
485 472
@@ -502,3 +489,71 @@ EXPORT_SYMBOL_GPL(cpu_bit_bitmap);
502 489
503const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL; 490const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL;
504EXPORT_SYMBOL(cpu_all_bits); 491EXPORT_SYMBOL(cpu_all_bits);
492
493#ifdef CONFIG_INIT_ALL_POSSIBLE
494static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly
495 = CPU_BITS_ALL;
496#else
497static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly;
498#endif
499const struct cpumask *const cpu_possible_mask = to_cpumask(cpu_possible_bits);
500EXPORT_SYMBOL(cpu_possible_mask);
501
502static DECLARE_BITMAP(cpu_online_bits, CONFIG_NR_CPUS) __read_mostly;
503const struct cpumask *const cpu_online_mask = to_cpumask(cpu_online_bits);
504EXPORT_SYMBOL(cpu_online_mask);
505
506static DECLARE_BITMAP(cpu_present_bits, CONFIG_NR_CPUS) __read_mostly;
507const struct cpumask *const cpu_present_mask = to_cpumask(cpu_present_bits);
508EXPORT_SYMBOL(cpu_present_mask);
509
510static DECLARE_BITMAP(cpu_active_bits, CONFIG_NR_CPUS) __read_mostly;
511const struct cpumask *const cpu_active_mask = to_cpumask(cpu_active_bits);
512EXPORT_SYMBOL(cpu_active_mask);
513
514void set_cpu_possible(unsigned int cpu, bool possible)
515{
516 if (possible)
517 cpumask_set_cpu(cpu, to_cpumask(cpu_possible_bits));
518 else
519 cpumask_clear_cpu(cpu, to_cpumask(cpu_possible_bits));
520}
521
522void set_cpu_present(unsigned int cpu, bool present)
523{
524 if (present)
525 cpumask_set_cpu(cpu, to_cpumask(cpu_present_bits));
526 else
527 cpumask_clear_cpu(cpu, to_cpumask(cpu_present_bits));
528}
529
530void set_cpu_online(unsigned int cpu, bool online)
531{
532 if (online)
533 cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits));
534 else
535 cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits));
536}
537
538void set_cpu_active(unsigned int cpu, bool active)
539{
540 if (active)
541 cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits));
542 else
543 cpumask_clear_cpu(cpu, to_cpumask(cpu_active_bits));
544}
545
546void init_cpu_present(const struct cpumask *src)
547{
548 cpumask_copy(to_cpumask(cpu_present_bits), src);
549}
550
551void init_cpu_possible(const struct cpumask *src)
552{
553 cpumask_copy(to_cpumask(cpu_possible_bits), src);
554}
555
556void init_cpu_online(const struct cpumask *src)
557{
558 cpumask_copy(to_cpumask(cpu_online_bits), src);
559}