Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* CPU control. |
2 | * (C) 2001, 2002, 2003, 2004 Rusty Russell | |
3 | * | |
4 | * This code is licenced under the GPL. | |
5 | */ | |
6 | #include <linux/proc_fs.h> | |
7 | #include <linux/smp.h> | |
8 | #include <linux/init.h> | |
9 | #include <linux/notifier.h> | |
10 | #include <linux/sched.h> | |
11 | #include <linux/unistd.h> | |
12 | #include <linux/cpu.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/kthread.h> | |
15 | #include <linux/stop_machine.h> | |
81615b62 | 16 | #include <linux/mutex.h> |
5a0e3ad6 | 17 | #include <linux/gfp.h> |
1da177e4 | 18 | |
98a79d6a | 19 | #ifdef CONFIG_SMP |
b3199c02 | 20 | /* Serializes the updates to cpu_online_mask, cpu_present_mask */ |
aa953877 | 21 | static DEFINE_MUTEX(cpu_add_remove_lock); |
1da177e4 | 22 | |
79a6cdeb LJ |
23 | /* |
24 | * The following two API's must be used when attempting | |
25 | * to serialize the updates to cpu_online_mask, cpu_present_mask. | |
26 | */ | |
27 | void cpu_maps_update_begin(void) | |
28 | { | |
29 | mutex_lock(&cpu_add_remove_lock); | |
30 | } | |
31 | ||
32 | void cpu_maps_update_done(void) | |
33 | { | |
34 | mutex_unlock(&cpu_add_remove_lock); | |
35 | } | |
36 | ||
5c113fbe | 37 | static RAW_NOTIFIER_HEAD(cpu_chain); |
1da177e4 | 38 | |
e3920fb4 RW |
39 | /* If set, cpu_up and cpu_down will return -EBUSY and do nothing. |
40 | * Should always be manipulated under cpu_add_remove_lock | |
41 | */ | |
42 | static int cpu_hotplug_disabled; | |
43 | ||
79a6cdeb LJ |
44 | #ifdef CONFIG_HOTPLUG_CPU |
45 | ||
d221938c GS |
46 | static struct { |
47 | struct task_struct *active_writer; | |
48 | struct mutex lock; /* Synchronizes accesses to refcount, */ | |
49 | /* | |
50 | * Also blocks the new readers during | |
51 | * an ongoing cpu hotplug operation. | |
52 | */ | |
53 | int refcount; | |
31950eb6 LT |
54 | } cpu_hotplug = { |
55 | .active_writer = NULL, | |
56 | .lock = __MUTEX_INITIALIZER(cpu_hotplug.lock), | |
57 | .refcount = 0, | |
58 | }; | |
d221938c | 59 | |
86ef5c9a | 60 | void get_online_cpus(void) |
a9d9baa1 | 61 | { |
d221938c GS |
62 | might_sleep(); |
63 | if (cpu_hotplug.active_writer == current) | |
aa953877 | 64 | return; |
d221938c GS |
65 | mutex_lock(&cpu_hotplug.lock); |
66 | cpu_hotplug.refcount++; | |
67 | mutex_unlock(&cpu_hotplug.lock); | |
68 | ||
a9d9baa1 | 69 | } |
86ef5c9a | 70 | EXPORT_SYMBOL_GPL(get_online_cpus); |
90d45d17 | 71 | |
86ef5c9a | 72 | void put_online_cpus(void) |
a9d9baa1 | 73 | { |
d221938c | 74 | if (cpu_hotplug.active_writer == current) |
aa953877 | 75 | return; |
d221938c | 76 | mutex_lock(&cpu_hotplug.lock); |
d2ba7e2a ON |
77 | if (!--cpu_hotplug.refcount && unlikely(cpu_hotplug.active_writer)) |
78 | wake_up_process(cpu_hotplug.active_writer); | |
d221938c GS |
79 | mutex_unlock(&cpu_hotplug.lock); |
80 | ||
a9d9baa1 | 81 | } |
86ef5c9a | 82 | EXPORT_SYMBOL_GPL(put_online_cpus); |
a9d9baa1 | 83 | |
d221938c GS |
84 | /* |
85 | * This ensures that the hotplug operation can begin only when the | |
86 | * refcount goes to zero. | |
87 | * | |
88 | * Note that during a cpu-hotplug operation, the new readers, if any, | |
89 | * will be blocked by the cpu_hotplug.lock | |
90 | * | |
d2ba7e2a ON |
91 | * Since cpu_hotplug_begin() is always called after invoking |
92 | * cpu_maps_update_begin(), we can be sure that only one writer is active. | |
d221938c GS |
93 | * |
94 | * Note that theoretically, there is a possibility of a livelock: | |
95 | * - Refcount goes to zero, last reader wakes up the sleeping | |
96 | * writer. | |
97 | * - Last reader unlocks the cpu_hotplug.lock. | |
98 | * - A new reader arrives at this moment, bumps up the refcount. | |
99 | * - The writer acquires the cpu_hotplug.lock finds the refcount | |
100 | * non zero and goes to sleep again. | |
101 | * | |
102 | * However, this is very difficult to achieve in practice since | |
86ef5c9a | 103 | * get_online_cpus() not an api which is called all that often. |
d221938c GS |
104 | * |
105 | */ | |
106 | static void cpu_hotplug_begin(void) | |
107 | { | |
d221938c | 108 | cpu_hotplug.active_writer = current; |
d2ba7e2a ON |
109 | |
110 | for (;;) { | |
111 | mutex_lock(&cpu_hotplug.lock); | |
112 | if (likely(!cpu_hotplug.refcount)) | |
113 | break; | |
114 | __set_current_state(TASK_UNINTERRUPTIBLE); | |
d221938c GS |
115 | mutex_unlock(&cpu_hotplug.lock); |
116 | schedule(); | |
d221938c | 117 | } |
d221938c GS |
118 | } |
119 | ||
120 | static void cpu_hotplug_done(void) | |
121 | { | |
122 | cpu_hotplug.active_writer = NULL; | |
123 | mutex_unlock(&cpu_hotplug.lock); | |
124 | } | |
79a6cdeb LJ |
125 | |
126 | #else /* #if CONFIG_HOTPLUG_CPU */ | |
127 | static void cpu_hotplug_begin(void) {} | |
128 | static void cpu_hotplug_done(void) {} | |
25985edc | 129 | #endif /* #else #if CONFIG_HOTPLUG_CPU */ |
79a6cdeb | 130 | |
1da177e4 | 131 | /* Need to know about CPUs going up/down? */ |
f7b16c10 | 132 | int __ref register_cpu_notifier(struct notifier_block *nb) |
1da177e4 | 133 | { |
bd5349cf | 134 | int ret; |
d221938c | 135 | cpu_maps_update_begin(); |
bd5349cf | 136 | ret = raw_notifier_chain_register(&cpu_chain, nb); |
d221938c | 137 | cpu_maps_update_done(); |
bd5349cf | 138 | return ret; |
1da177e4 | 139 | } |
65edc68c | 140 | |
e9fb7631 AM |
141 | static int __cpu_notify(unsigned long val, void *v, int nr_to_call, |
142 | int *nr_calls) | |
143 | { | |
e6bde73b AM |
144 | int ret; |
145 | ||
146 | ret = __raw_notifier_call_chain(&cpu_chain, val, v, nr_to_call, | |
e9fb7631 | 147 | nr_calls); |
e6bde73b AM |
148 | |
149 | return notifier_to_errno(ret); | |
e9fb7631 AM |
150 | } |
151 | ||
152 | static int cpu_notify(unsigned long val, void *v) | |
153 | { | |
154 | return __cpu_notify(val, v, -1, NULL); | |
155 | } | |
156 | ||
00b9b0af LT |
157 | #ifdef CONFIG_HOTPLUG_CPU |
158 | ||
e9fb7631 AM |
159 | static void cpu_notify_nofail(unsigned long val, void *v) |
160 | { | |
00b9b0af | 161 | BUG_ON(cpu_notify(val, v)); |
e9fb7631 | 162 | } |
1da177e4 LT |
163 | EXPORT_SYMBOL(register_cpu_notifier); |
164 | ||
9647155f | 165 | void __ref unregister_cpu_notifier(struct notifier_block *nb) |
1da177e4 | 166 | { |
d221938c | 167 | cpu_maps_update_begin(); |
bd5349cf | 168 | raw_notifier_chain_unregister(&cpu_chain, nb); |
d221938c | 169 | cpu_maps_update_done(); |
1da177e4 LT |
170 | } |
171 | EXPORT_SYMBOL(unregister_cpu_notifier); | |
172 | ||
1da177e4 LT |
173 | static inline void check_for_tasks(int cpu) |
174 | { | |
175 | struct task_struct *p; | |
176 | ||
177 | write_lock_irq(&tasklist_lock); | |
178 | for_each_process(p) { | |
11854247 | 179 | if (task_cpu(p) == cpu && p->state == TASK_RUNNING && |
1da177e4 LT |
180 | (!cputime_eq(p->utime, cputime_zero) || |
181 | !cputime_eq(p->stime, cputime_zero))) | |
9d3cfc4c FP |
182 | printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d " |
183 | "(state = %ld, flags = %x)\n", | |
184 | p->comm, task_pid_nr(p), cpu, | |
185 | p->state, p->flags); | |
1da177e4 LT |
186 | } |
187 | write_unlock_irq(&tasklist_lock); | |
188 | } | |
189 | ||
db912f96 AK |
190 | struct take_cpu_down_param { |
191 | unsigned long mod; | |
192 | void *hcpu; | |
193 | }; | |
194 | ||
1da177e4 | 195 | /* Take this CPU down. */ |
514a20a5 | 196 | static int __ref take_cpu_down(void *_param) |
1da177e4 | 197 | { |
db912f96 | 198 | struct take_cpu_down_param *param = _param; |
1da177e4 LT |
199 | int err; |
200 | ||
1da177e4 LT |
201 | /* Ensure this CPU doesn't handle any more interrupts. */ |
202 | err = __cpu_disable(); | |
203 | if (err < 0) | |
f3705136 | 204 | return err; |
1da177e4 | 205 | |
e9fb7631 | 206 | cpu_notify(CPU_DYING | param->mod, param->hcpu); |
f3705136 | 207 | return 0; |
1da177e4 LT |
208 | } |
209 | ||
e3920fb4 | 210 | /* Requires cpu_add_remove_lock to be held */ |
514a20a5 | 211 | static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) |
1da177e4 | 212 | { |
e7407dcc | 213 | int err, nr_calls = 0; |
e7407dcc | 214 | void *hcpu = (void *)(long)cpu; |
8bb78442 | 215 | unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; |
db912f96 AK |
216 | struct take_cpu_down_param tcd_param = { |
217 | .mod = mod, | |
218 | .hcpu = hcpu, | |
219 | }; | |
1da177e4 | 220 | |
e3920fb4 RW |
221 | if (num_online_cpus() == 1) |
222 | return -EBUSY; | |
1da177e4 | 223 | |
e3920fb4 RW |
224 | if (!cpu_online(cpu)) |
225 | return -EINVAL; | |
1da177e4 | 226 | |
d221938c | 227 | cpu_hotplug_begin(); |
4d51985e | 228 | |
e9fb7631 | 229 | err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls); |
e6bde73b | 230 | if (err) { |
a0d8cdb6 | 231 | nr_calls--; |
e9fb7631 | 232 | __cpu_notify(CPU_DOWN_FAILED | mod, hcpu, nr_calls, NULL); |
1da177e4 | 233 | printk("%s: attempt to take down CPU %u failed\n", |
af1f16d0 | 234 | __func__, cpu); |
baaca49f | 235 | goto out_release; |
1da177e4 LT |
236 | } |
237 | ||
e0b582ec | 238 | err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu)); |
04321587 | 239 | if (err) { |
1da177e4 | 240 | /* CPU didn't die: tell everyone. Can't complain. */ |
e9fb7631 | 241 | cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu); |
1da177e4 | 242 | |
6a1bdc1b | 243 | goto out_release; |
8fa1d7d3 | 244 | } |
04321587 | 245 | BUG_ON(cpu_online(cpu)); |
1da177e4 | 246 | |
48c5ccae PZ |
247 | /* |
248 | * The migration_call() CPU_DYING callback will have removed all | |
249 | * runnable tasks from the cpu, there's only the idle task left now | |
250 | * that the migration thread is done doing the stop_machine thing. | |
51a96c77 PZ |
251 | * |
252 | * Wait for the stop thread to go away. | |
48c5ccae | 253 | */ |
51a96c77 PZ |
254 | while (!idle_cpu(cpu)) |
255 | cpu_relax(); | |
1da177e4 LT |
256 | |
257 | /* This actually kills the CPU. */ | |
258 | __cpu_die(cpu); | |
259 | ||
1da177e4 | 260 | /* CPU is completely dead: tell everyone. Too late to complain. */ |
e9fb7631 | 261 | cpu_notify_nofail(CPU_DEAD | mod, hcpu); |
1da177e4 LT |
262 | |
263 | check_for_tasks(cpu); | |
264 | ||
baaca49f | 265 | out_release: |
d221938c | 266 | cpu_hotplug_done(); |
e9fb7631 AM |
267 | if (!err) |
268 | cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu); | |
e3920fb4 RW |
269 | return err; |
270 | } | |
271 | ||
514a20a5 | 272 | int __ref cpu_down(unsigned int cpu) |
e3920fb4 | 273 | { |
9ea09af3 | 274 | int err; |
e3920fb4 | 275 | |
d221938c | 276 | cpu_maps_update_begin(); |
e761b772 MK |
277 | |
278 | if (cpu_hotplug_disabled) { | |
e3920fb4 | 279 | err = -EBUSY; |
e761b772 MK |
280 | goto out; |
281 | } | |
282 | ||
e761b772 | 283 | err = _cpu_down(cpu, 0); |
e3920fb4 | 284 | |
e761b772 | 285 | out: |
d221938c | 286 | cpu_maps_update_done(); |
1da177e4 LT |
287 | return err; |
288 | } | |
b62b8ef9 | 289 | EXPORT_SYMBOL(cpu_down); |
1da177e4 LT |
290 | #endif /*CONFIG_HOTPLUG_CPU*/ |
291 | ||
e3920fb4 | 292 | /* Requires cpu_add_remove_lock to be held */ |
8bb78442 | 293 | static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) |
1da177e4 | 294 | { |
baaca49f | 295 | int ret, nr_calls = 0; |
1da177e4 | 296 | void *hcpu = (void *)(long)cpu; |
8bb78442 | 297 | unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; |
1da177e4 | 298 | |
e3920fb4 RW |
299 | if (cpu_online(cpu) || !cpu_present(cpu)) |
300 | return -EINVAL; | |
90d45d17 | 301 | |
d221938c | 302 | cpu_hotplug_begin(); |
e9fb7631 | 303 | ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls); |
e6bde73b | 304 | if (ret) { |
a0d8cdb6 | 305 | nr_calls--; |
4d51985e | 306 | printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n", |
af1f16d0 | 307 | __func__, cpu); |
1da177e4 LT |
308 | goto out_notify; |
309 | } | |
310 | ||
311 | /* Arch-specific enabling code. */ | |
312 | ret = __cpu_up(cpu); | |
313 | if (ret != 0) | |
314 | goto out_notify; | |
6978c705 | 315 | BUG_ON(!cpu_online(cpu)); |
1da177e4 LT |
316 | |
317 | /* Now call notifier in preparation. */ | |
e9fb7631 | 318 | cpu_notify(CPU_ONLINE | mod, hcpu); |
1da177e4 LT |
319 | |
320 | out_notify: | |
321 | if (ret != 0) | |
e9fb7631 | 322 | __cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL); |
d221938c | 323 | cpu_hotplug_done(); |
e3920fb4 RW |
324 | |
325 | return ret; | |
326 | } | |
327 | ||
b282b6f8 | 328 | int __cpuinit cpu_up(unsigned int cpu) |
e3920fb4 RW |
329 | { |
330 | int err = 0; | |
cf23422b | 331 | |
332 | #ifdef CONFIG_MEMORY_HOTPLUG | |
333 | int nid; | |
334 | pg_data_t *pgdat; | |
335 | #endif | |
336 | ||
e0b582ec | 337 | if (!cpu_possible(cpu)) { |
73e753a5 KH |
338 | printk(KERN_ERR "can't online cpu %d because it is not " |
339 | "configured as may-hotadd at boot time\n", cpu); | |
87d5e023 | 340 | #if defined(CONFIG_IA64) |
73e753a5 KH |
341 | printk(KERN_ERR "please check additional_cpus= boot " |
342 | "parameter\n"); | |
343 | #endif | |
344 | return -EINVAL; | |
345 | } | |
e3920fb4 | 346 | |
cf23422b | 347 | #ifdef CONFIG_MEMORY_HOTPLUG |
348 | nid = cpu_to_node(cpu); | |
349 | if (!node_online(nid)) { | |
350 | err = mem_online_node(nid); | |
351 | if (err) | |
352 | return err; | |
353 | } | |
354 | ||
355 | pgdat = NODE_DATA(nid); | |
356 | if (!pgdat) { | |
357 | printk(KERN_ERR | |
358 | "Can't online cpu %d due to NULL pgdat\n", cpu); | |
359 | return -ENOMEM; | |
360 | } | |
361 | ||
4eaf3f64 HL |
362 | if (pgdat->node_zonelists->_zonerefs->zone == NULL) { |
363 | mutex_lock(&zonelists_mutex); | |
1f522509 | 364 | build_all_zonelists(NULL); |
4eaf3f64 HL |
365 | mutex_unlock(&zonelists_mutex); |
366 | } | |
cf23422b | 367 | #endif |
368 | ||
d221938c | 369 | cpu_maps_update_begin(); |
e761b772 MK |
370 | |
371 | if (cpu_hotplug_disabled) { | |
e3920fb4 | 372 | err = -EBUSY; |
e761b772 MK |
373 | goto out; |
374 | } | |
375 | ||
376 | err = _cpu_up(cpu, 0); | |
377 | ||
e761b772 | 378 | out: |
d221938c | 379 | cpu_maps_update_done(); |
e3920fb4 RW |
380 | return err; |
381 | } | |
382 | ||
f3de4be9 | 383 | #ifdef CONFIG_PM_SLEEP_SMP |
e0b582ec | 384 | static cpumask_var_t frozen_cpus; |
e3920fb4 | 385 | |
3fb82d56 SS |
386 | void __weak arch_disable_nonboot_cpus_begin(void) |
387 | { | |
388 | } | |
389 | ||
390 | void __weak arch_disable_nonboot_cpus_end(void) | |
391 | { | |
392 | } | |
393 | ||
e3920fb4 RW |
394 | int disable_nonboot_cpus(void) |
395 | { | |
e9a5f426 | 396 | int cpu, first_cpu, error = 0; |
e3920fb4 | 397 | |
d221938c | 398 | cpu_maps_update_begin(); |
e0b582ec | 399 | first_cpu = cpumask_first(cpu_online_mask); |
9ee349ad XF |
400 | /* |
401 | * We take down all of the non-boot CPUs in one shot to avoid races | |
e3920fb4 RW |
402 | * with the userspace trying to use the CPU hotplug at the same time |
403 | */ | |
e0b582ec | 404 | cpumask_clear(frozen_cpus); |
3fb82d56 | 405 | arch_disable_nonboot_cpus_begin(); |
6ad4c188 | 406 | |
e3920fb4 RW |
407 | printk("Disabling non-boot CPUs ...\n"); |
408 | for_each_online_cpu(cpu) { | |
409 | if (cpu == first_cpu) | |
410 | continue; | |
8bb78442 | 411 | error = _cpu_down(cpu, 1); |
feae3203 | 412 | if (!error) |
e0b582ec | 413 | cpumask_set_cpu(cpu, frozen_cpus); |
feae3203 | 414 | else { |
e3920fb4 RW |
415 | printk(KERN_ERR "Error taking CPU%d down: %d\n", |
416 | cpu, error); | |
417 | break; | |
418 | } | |
419 | } | |
86886e55 | 420 | |
3fb82d56 SS |
421 | arch_disable_nonboot_cpus_end(); |
422 | ||
e3920fb4 RW |
423 | if (!error) { |
424 | BUG_ON(num_online_cpus() > 1); | |
425 | /* Make sure the CPUs won't be enabled by someone else */ | |
426 | cpu_hotplug_disabled = 1; | |
427 | } else { | |
e1d9fd2e | 428 | printk(KERN_ERR "Non-boot CPUs are not disabled\n"); |
e3920fb4 | 429 | } |
d221938c | 430 | cpu_maps_update_done(); |
e3920fb4 RW |
431 | return error; |
432 | } | |
433 | ||
d0af9eed SS |
434 | void __weak arch_enable_nonboot_cpus_begin(void) |
435 | { | |
436 | } | |
437 | ||
438 | void __weak arch_enable_nonboot_cpus_end(void) | |
439 | { | |
440 | } | |
441 | ||
fa7303e2 | 442 | void __ref enable_nonboot_cpus(void) |
e3920fb4 RW |
443 | { |
444 | int cpu, error; | |
445 | ||
446 | /* Allow everyone to use the CPU hotplug again */ | |
d221938c | 447 | cpu_maps_update_begin(); |
e3920fb4 | 448 | cpu_hotplug_disabled = 0; |
e0b582ec | 449 | if (cpumask_empty(frozen_cpus)) |
1d64b9cb | 450 | goto out; |
e3920fb4 | 451 | |
4d51985e | 452 | printk(KERN_INFO "Enabling non-boot CPUs ...\n"); |
d0af9eed SS |
453 | |
454 | arch_enable_nonboot_cpus_begin(); | |
455 | ||
e0b582ec | 456 | for_each_cpu(cpu, frozen_cpus) { |
8bb78442 | 457 | error = _cpu_up(cpu, 1); |
e3920fb4 | 458 | if (!error) { |
4d51985e | 459 | printk(KERN_INFO "CPU%d is up\n", cpu); |
e3920fb4 RW |
460 | continue; |
461 | } | |
1d64b9cb | 462 | printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error); |
e3920fb4 | 463 | } |
d0af9eed SS |
464 | |
465 | arch_enable_nonboot_cpus_end(); | |
466 | ||
e0b582ec | 467 | cpumask_clear(frozen_cpus); |
1d64b9cb | 468 | out: |
d221938c | 469 | cpu_maps_update_done(); |
1da177e4 | 470 | } |
e0b582ec RR |
471 | |
472 | static int alloc_frozen_cpus(void) | |
473 | { | |
474 | if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO)) | |
475 | return -ENOMEM; | |
476 | return 0; | |
477 | } | |
478 | core_initcall(alloc_frozen_cpus); | |
f3de4be9 | 479 | #endif /* CONFIG_PM_SLEEP_SMP */ |
68f4f1ec | 480 | |
e545a614 MS |
481 | /** |
482 | * notify_cpu_starting(cpu) - call the CPU_STARTING notifiers | |
483 | * @cpu: cpu that just started | |
484 | * | |
485 | * This function calls the cpu_chain notifiers with CPU_STARTING. | |
486 | * It must be called by the arch code on the new cpu, before the new cpu | |
487 | * enables interrupts and before the "boot" cpu returns from __cpu_up(). | |
488 | */ | |
84196414 | 489 | void __cpuinit notify_cpu_starting(unsigned int cpu) |
e545a614 MS |
490 | { |
491 | unsigned long val = CPU_STARTING; | |
492 | ||
493 | #ifdef CONFIG_PM_SLEEP_SMP | |
e0b582ec | 494 | if (frozen_cpus != NULL && cpumask_test_cpu(cpu, frozen_cpus)) |
e545a614 MS |
495 | val = CPU_STARTING_FROZEN; |
496 | #endif /* CONFIG_PM_SLEEP_SMP */ | |
e9fb7631 | 497 | cpu_notify(val, (void *)(long)cpu); |
e545a614 MS |
498 | } |
499 | ||
68f4f1ec | 500 | #endif /* CONFIG_SMP */ |
b8d317d1 | 501 | |
e56b3bc7 LT |
502 | /* |
503 | * cpu_bit_bitmap[] is a special, "compressed" data structure that | |
504 | * represents all NR_CPUS bits binary values of 1<<nr. | |
505 | * | |
e0b582ec | 506 | * It is used by cpumask_of() to get a constant address to a CPU |
e56b3bc7 LT |
507 | * mask value that has a single bit set only. |
508 | */ | |
b8d317d1 | 509 | |
e56b3bc7 | 510 | /* cpu_bit_bitmap[0] is empty - so we can back into it */ |
4d51985e | 511 | #define MASK_DECLARE_1(x) [x+1][0] = (1UL << (x)) |
e56b3bc7 LT |
512 | #define MASK_DECLARE_2(x) MASK_DECLARE_1(x), MASK_DECLARE_1(x+1) |
513 | #define MASK_DECLARE_4(x) MASK_DECLARE_2(x), MASK_DECLARE_2(x+2) | |
514 | #define MASK_DECLARE_8(x) MASK_DECLARE_4(x), MASK_DECLARE_4(x+4) | |
b8d317d1 | 515 | |
e56b3bc7 LT |
516 | const unsigned long cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)] = { |
517 | ||
518 | MASK_DECLARE_8(0), MASK_DECLARE_8(8), | |
519 | MASK_DECLARE_8(16), MASK_DECLARE_8(24), | |
520 | #if BITS_PER_LONG > 32 | |
521 | MASK_DECLARE_8(32), MASK_DECLARE_8(40), | |
522 | MASK_DECLARE_8(48), MASK_DECLARE_8(56), | |
b8d317d1 MT |
523 | #endif |
524 | }; | |
e56b3bc7 | 525 | EXPORT_SYMBOL_GPL(cpu_bit_bitmap); |
2d3854a3 RR |
526 | |
527 | const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL; | |
528 | EXPORT_SYMBOL(cpu_all_bits); | |
b3199c02 RR |
529 | |
530 | #ifdef CONFIG_INIT_ALL_POSSIBLE | |
531 | static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly | |
532 | = CPU_BITS_ALL; | |
533 | #else | |
534 | static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly; | |
535 | #endif | |
536 | const struct cpumask *const cpu_possible_mask = to_cpumask(cpu_possible_bits); | |
537 | EXPORT_SYMBOL(cpu_possible_mask); | |
538 | ||
539 | static DECLARE_BITMAP(cpu_online_bits, CONFIG_NR_CPUS) __read_mostly; | |
540 | const struct cpumask *const cpu_online_mask = to_cpumask(cpu_online_bits); | |
541 | EXPORT_SYMBOL(cpu_online_mask); | |
542 | ||
543 | static DECLARE_BITMAP(cpu_present_bits, CONFIG_NR_CPUS) __read_mostly; | |
544 | const struct cpumask *const cpu_present_mask = to_cpumask(cpu_present_bits); | |
545 | EXPORT_SYMBOL(cpu_present_mask); | |
546 | ||
547 | static DECLARE_BITMAP(cpu_active_bits, CONFIG_NR_CPUS) __read_mostly; | |
548 | const struct cpumask *const cpu_active_mask = to_cpumask(cpu_active_bits); | |
549 | EXPORT_SYMBOL(cpu_active_mask); | |
3fa41520 RR |
550 | |
551 | void set_cpu_possible(unsigned int cpu, bool possible) | |
552 | { | |
553 | if (possible) | |
554 | cpumask_set_cpu(cpu, to_cpumask(cpu_possible_bits)); | |
555 | else | |
556 | cpumask_clear_cpu(cpu, to_cpumask(cpu_possible_bits)); | |
557 | } | |
558 | ||
559 | void set_cpu_present(unsigned int cpu, bool present) | |
560 | { | |
561 | if (present) | |
562 | cpumask_set_cpu(cpu, to_cpumask(cpu_present_bits)); | |
563 | else | |
564 | cpumask_clear_cpu(cpu, to_cpumask(cpu_present_bits)); | |
565 | } | |
566 | ||
567 | void set_cpu_online(unsigned int cpu, bool online) | |
568 | { | |
569 | if (online) | |
570 | cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits)); | |
571 | else | |
572 | cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits)); | |
573 | } | |
574 | ||
575 | void set_cpu_active(unsigned int cpu, bool active) | |
576 | { | |
577 | if (active) | |
578 | cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits)); | |
579 | else | |
580 | cpumask_clear_cpu(cpu, to_cpumask(cpu_active_bits)); | |
581 | } | |
582 | ||
583 | void init_cpu_present(const struct cpumask *src) | |
584 | { | |
585 | cpumask_copy(to_cpumask(cpu_present_bits), src); | |
586 | } | |
587 | ||
588 | void init_cpu_possible(const struct cpumask *src) | |
589 | { | |
590 | cpumask_copy(to_cpumask(cpu_possible_bits), src); | |
591 | } | |
592 | ||
593 | void init_cpu_online(const struct cpumask *src) | |
594 | { | |
595 | cpumask_copy(to_cpumask(cpu_online_bits), src); | |
596 | } |