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 | |
bd5349cf | 23 | static __cpuinitdata RAW_NOTIFIER_HEAD(cpu_chain); |
1da177e4 | 24 | |
e3920fb4 RW |
25 | /* If set, cpu_up and cpu_down will return -EBUSY and do nothing. |
26 | * Should always be manipulated under cpu_add_remove_lock | |
27 | */ | |
28 | static int cpu_hotplug_disabled; | |
29 | ||
d221938c GS |
30 | static struct { |
31 | struct task_struct *active_writer; | |
32 | struct mutex lock; /* Synchronizes accesses to refcount, */ | |
33 | /* | |
34 | * Also blocks the new readers during | |
35 | * an ongoing cpu hotplug operation. | |
36 | */ | |
37 | int refcount; | |
31950eb6 LT |
38 | } cpu_hotplug = { |
39 | .active_writer = NULL, | |
40 | .lock = __MUTEX_INITIALIZER(cpu_hotplug.lock), | |
41 | .refcount = 0, | |
42 | }; | |
d221938c GS |
43 | |
44 | #ifdef CONFIG_HOTPLUG_CPU | |
90d45d17 | 45 | |
86ef5c9a | 46 | void get_online_cpus(void) |
a9d9baa1 | 47 | { |
d221938c GS |
48 | might_sleep(); |
49 | if (cpu_hotplug.active_writer == current) | |
aa953877 | 50 | return; |
d221938c GS |
51 | mutex_lock(&cpu_hotplug.lock); |
52 | cpu_hotplug.refcount++; | |
53 | mutex_unlock(&cpu_hotplug.lock); | |
54 | ||
a9d9baa1 | 55 | } |
86ef5c9a | 56 | EXPORT_SYMBOL_GPL(get_online_cpus); |
90d45d17 | 57 | |
86ef5c9a | 58 | void put_online_cpus(void) |
a9d9baa1 | 59 | { |
d221938c | 60 | if (cpu_hotplug.active_writer == current) |
aa953877 | 61 | return; |
d221938c | 62 | mutex_lock(&cpu_hotplug.lock); |
d2ba7e2a ON |
63 | if (!--cpu_hotplug.refcount && unlikely(cpu_hotplug.active_writer)) |
64 | wake_up_process(cpu_hotplug.active_writer); | |
d221938c GS |
65 | mutex_unlock(&cpu_hotplug.lock); |
66 | ||
a9d9baa1 | 67 | } |
86ef5c9a | 68 | EXPORT_SYMBOL_GPL(put_online_cpus); |
a9d9baa1 | 69 | |
a9d9baa1 | 70 | #endif /* CONFIG_HOTPLUG_CPU */ |
90d45d17 | 71 | |
d221938c GS |
72 | /* |
73 | * The following two API's must be used when attempting | |
b3199c02 | 74 | * to serialize the updates to cpu_online_mask, cpu_present_mask. |
d221938c GS |
75 | */ |
76 | void cpu_maps_update_begin(void) | |
77 | { | |
78 | mutex_lock(&cpu_add_remove_lock); | |
79 | } | |
80 | ||
81 | void cpu_maps_update_done(void) | |
82 | { | |
83 | mutex_unlock(&cpu_add_remove_lock); | |
84 | } | |
85 | ||
86 | /* | |
87 | * This ensures that the hotplug operation can begin only when the | |
88 | * refcount goes to zero. | |
89 | * | |
90 | * Note that during a cpu-hotplug operation, the new readers, if any, | |
91 | * will be blocked by the cpu_hotplug.lock | |
92 | * | |
d2ba7e2a ON |
93 | * Since cpu_hotplug_begin() is always called after invoking |
94 | * cpu_maps_update_begin(), we can be sure that only one writer is active. | |
d221938c GS |
95 | * |
96 | * Note that theoretically, there is a possibility of a livelock: | |
97 | * - Refcount goes to zero, last reader wakes up the sleeping | |
98 | * writer. | |
99 | * - Last reader unlocks the cpu_hotplug.lock. | |
100 | * - A new reader arrives at this moment, bumps up the refcount. | |
101 | * - The writer acquires the cpu_hotplug.lock finds the refcount | |
102 | * non zero and goes to sleep again. | |
103 | * | |
104 | * However, this is very difficult to achieve in practice since | |
86ef5c9a | 105 | * get_online_cpus() not an api which is called all that often. |
d221938c GS |
106 | * |
107 | */ | |
108 | static void cpu_hotplug_begin(void) | |
109 | { | |
d221938c | 110 | cpu_hotplug.active_writer = current; |
d2ba7e2a ON |
111 | |
112 | for (;;) { | |
113 | mutex_lock(&cpu_hotplug.lock); | |
114 | if (likely(!cpu_hotplug.refcount)) | |
115 | break; | |
116 | __set_current_state(TASK_UNINTERRUPTIBLE); | |
d221938c GS |
117 | mutex_unlock(&cpu_hotplug.lock); |
118 | schedule(); | |
d221938c | 119 | } |
d221938c GS |
120 | } |
121 | ||
122 | static void cpu_hotplug_done(void) | |
123 | { | |
124 | cpu_hotplug.active_writer = NULL; | |
125 | mutex_unlock(&cpu_hotplug.lock); | |
126 | } | |
1da177e4 | 127 | /* Need to know about CPUs going up/down? */ |
f7b16c10 | 128 | int __ref register_cpu_notifier(struct notifier_block *nb) |
1da177e4 | 129 | { |
bd5349cf | 130 | int ret; |
d221938c | 131 | cpu_maps_update_begin(); |
bd5349cf | 132 | ret = raw_notifier_chain_register(&cpu_chain, nb); |
d221938c | 133 | cpu_maps_update_done(); |
bd5349cf | 134 | return ret; |
1da177e4 | 135 | } |
65edc68c CS |
136 | |
137 | #ifdef CONFIG_HOTPLUG_CPU | |
138 | ||
1da177e4 LT |
139 | EXPORT_SYMBOL(register_cpu_notifier); |
140 | ||
9647155f | 141 | void __ref unregister_cpu_notifier(struct notifier_block *nb) |
1da177e4 | 142 | { |
d221938c | 143 | cpu_maps_update_begin(); |
bd5349cf | 144 | raw_notifier_chain_unregister(&cpu_chain, nb); |
d221938c | 145 | cpu_maps_update_done(); |
1da177e4 LT |
146 | } |
147 | EXPORT_SYMBOL(unregister_cpu_notifier); | |
148 | ||
1da177e4 LT |
149 | static inline void check_for_tasks(int cpu) |
150 | { | |
151 | struct task_struct *p; | |
152 | ||
153 | write_lock_irq(&tasklist_lock); | |
154 | for_each_process(p) { | |
11854247 | 155 | if (task_cpu(p) == cpu && p->state == TASK_RUNNING && |
1da177e4 LT |
156 | (!cputime_eq(p->utime, cputime_zero) || |
157 | !cputime_eq(p->stime, cputime_zero))) | |
9d3cfc4c FP |
158 | printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d " |
159 | "(state = %ld, flags = %x)\n", | |
160 | p->comm, task_pid_nr(p), cpu, | |
161 | p->state, p->flags); | |
1da177e4 LT |
162 | } |
163 | write_unlock_irq(&tasklist_lock); | |
164 | } | |
165 | ||
db912f96 | 166 | struct take_cpu_down_param { |
6a1bdc1b | 167 | struct task_struct *caller; |
db912f96 AK |
168 | unsigned long mod; |
169 | void *hcpu; | |
170 | }; | |
171 | ||
1da177e4 | 172 | /* Take this CPU down. */ |
514a20a5 | 173 | static int __ref take_cpu_down(void *_param) |
1da177e4 | 174 | { |
db912f96 | 175 | struct take_cpu_down_param *param = _param; |
6a1bdc1b | 176 | unsigned int cpu = (unsigned long)param->hcpu; |
1da177e4 LT |
177 | int err; |
178 | ||
1da177e4 LT |
179 | /* Ensure this CPU doesn't handle any more interrupts. */ |
180 | err = __cpu_disable(); | |
181 | if (err < 0) | |
f3705136 | 182 | return err; |
1da177e4 | 183 | |
3ba35573 MS |
184 | raw_notifier_call_chain(&cpu_chain, CPU_DYING | param->mod, |
185 | param->hcpu); | |
186 | ||
6a1bdc1b ON |
187 | if (task_cpu(param->caller) == cpu) |
188 | move_task_off_dead_cpu(cpu, param->caller); | |
f3705136 ZM |
189 | /* Force idle task to run as soon as we yield: it should |
190 | immediately notice cpu is offline and die quickly. */ | |
191 | sched_idle_next(); | |
192 | return 0; | |
1da177e4 LT |
193 | } |
194 | ||
e3920fb4 | 195 | /* Requires cpu_add_remove_lock to be held */ |
514a20a5 | 196 | static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) |
1da177e4 | 197 | { |
e7407dcc | 198 | int err, nr_calls = 0; |
e7407dcc | 199 | void *hcpu = (void *)(long)cpu; |
8bb78442 | 200 | unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; |
db912f96 | 201 | struct take_cpu_down_param tcd_param = { |
6a1bdc1b | 202 | .caller = current, |
db912f96 AK |
203 | .mod = mod, |
204 | .hcpu = hcpu, | |
205 | }; | |
1da177e4 | 206 | |
e3920fb4 RW |
207 | if (num_online_cpus() == 1) |
208 | return -EBUSY; | |
1da177e4 | 209 | |
e3920fb4 RW |
210 | if (!cpu_online(cpu)) |
211 | return -EINVAL; | |
1da177e4 | 212 | |
d221938c | 213 | cpu_hotplug_begin(); |
9ee349ad | 214 | set_cpu_active(cpu, false); |
8bb78442 | 215 | err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod, |
e7407dcc | 216 | hcpu, -1, &nr_calls); |
1da177e4 | 217 | if (err == NOTIFY_BAD) { |
6ad4c188 PZ |
218 | set_cpu_active(cpu, true); |
219 | ||
a0d8cdb6 | 220 | nr_calls--; |
8bb78442 RW |
221 | __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod, |
222 | hcpu, nr_calls, NULL); | |
1da177e4 | 223 | printk("%s: attempt to take down CPU %u failed\n", |
af1f16d0 | 224 | __func__, cpu); |
baaca49f GS |
225 | err = -EINVAL; |
226 | goto out_release; | |
1da177e4 LT |
227 | } |
228 | ||
e0b582ec | 229 | err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu)); |
04321587 | 230 | if (err) { |
6ad4c188 | 231 | set_cpu_active(cpu, true); |
1da177e4 | 232 | /* CPU didn't die: tell everyone. Can't complain. */ |
8bb78442 | 233 | if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod, |
e7407dcc | 234 | hcpu) == NOTIFY_BAD) |
1da177e4 LT |
235 | BUG(); |
236 | ||
6a1bdc1b | 237 | goto out_release; |
8fa1d7d3 | 238 | } |
04321587 | 239 | BUG_ON(cpu_online(cpu)); |
1da177e4 LT |
240 | |
241 | /* Wait for it to sleep (leaving idle task). */ | |
242 | while (!idle_cpu(cpu)) | |
243 | yield(); | |
244 | ||
245 | /* This actually kills the CPU. */ | |
246 | __cpu_die(cpu); | |
247 | ||
1da177e4 | 248 | /* CPU is completely dead: tell everyone. Too late to complain. */ |
8bb78442 RW |
249 | if (raw_notifier_call_chain(&cpu_chain, CPU_DEAD | mod, |
250 | hcpu) == NOTIFY_BAD) | |
1da177e4 LT |
251 | BUG(); |
252 | ||
253 | check_for_tasks(cpu); | |
254 | ||
baaca49f | 255 | out_release: |
d221938c | 256 | cpu_hotplug_done(); |
3da1c84c ON |
257 | if (!err) { |
258 | if (raw_notifier_call_chain(&cpu_chain, CPU_POST_DEAD | mod, | |
259 | hcpu) == NOTIFY_BAD) | |
260 | BUG(); | |
261 | } | |
e3920fb4 RW |
262 | return err; |
263 | } | |
264 | ||
514a20a5 | 265 | int __ref cpu_down(unsigned int cpu) |
e3920fb4 | 266 | { |
9ea09af3 | 267 | int err; |
e3920fb4 | 268 | |
d221938c | 269 | cpu_maps_update_begin(); |
e761b772 MK |
270 | |
271 | if (cpu_hotplug_disabled) { | |
e3920fb4 | 272 | err = -EBUSY; |
e761b772 MK |
273 | goto out; |
274 | } | |
275 | ||
e761b772 | 276 | err = _cpu_down(cpu, 0); |
e3920fb4 | 277 | |
e761b772 | 278 | out: |
d221938c | 279 | cpu_maps_update_done(); |
1da177e4 LT |
280 | return err; |
281 | } | |
b62b8ef9 | 282 | EXPORT_SYMBOL(cpu_down); |
1da177e4 LT |
283 | #endif /*CONFIG_HOTPLUG_CPU*/ |
284 | ||
e3920fb4 | 285 | /* Requires cpu_add_remove_lock to be held */ |
8bb78442 | 286 | static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) |
1da177e4 | 287 | { |
baaca49f | 288 | int ret, nr_calls = 0; |
1da177e4 | 289 | void *hcpu = (void *)(long)cpu; |
8bb78442 | 290 | unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; |
1da177e4 | 291 | |
e3920fb4 RW |
292 | if (cpu_online(cpu) || !cpu_present(cpu)) |
293 | return -EINVAL; | |
90d45d17 | 294 | |
d221938c | 295 | cpu_hotplug_begin(); |
8bb78442 | 296 | ret = __raw_notifier_call_chain(&cpu_chain, CPU_UP_PREPARE | mod, hcpu, |
baaca49f | 297 | -1, &nr_calls); |
1da177e4 | 298 | if (ret == NOTIFY_BAD) { |
a0d8cdb6 | 299 | nr_calls--; |
1da177e4 | 300 | printk("%s: attempt to bring up CPU %u failed\n", |
af1f16d0 | 301 | __func__, cpu); |
1da177e4 LT |
302 | ret = -EINVAL; |
303 | goto out_notify; | |
304 | } | |
305 | ||
306 | /* Arch-specific enabling code. */ | |
307 | ret = __cpu_up(cpu); | |
308 | if (ret != 0) | |
309 | goto out_notify; | |
6978c705 | 310 | BUG_ON(!cpu_online(cpu)); |
1da177e4 | 311 | |
2b17fa50 | 312 | set_cpu_active(cpu, true); |
279ef6bb | 313 | |
1da177e4 | 314 | /* Now call notifier in preparation. */ |
8bb78442 | 315 | raw_notifier_call_chain(&cpu_chain, CPU_ONLINE | mod, hcpu); |
1da177e4 LT |
316 | |
317 | out_notify: | |
318 | if (ret != 0) | |
baaca49f | 319 | __raw_notifier_call_chain(&cpu_chain, |
8bb78442 | 320 | CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL); |
d221938c | 321 | cpu_hotplug_done(); |
e3920fb4 RW |
322 | |
323 | return ret; | |
324 | } | |
325 | ||
b282b6f8 | 326 | int __cpuinit cpu_up(unsigned int cpu) |
e3920fb4 RW |
327 | { |
328 | int err = 0; | |
cf23422b | 329 | |
330 | #ifdef CONFIG_MEMORY_HOTPLUG | |
331 | int nid; | |
332 | pg_data_t *pgdat; | |
333 | #endif | |
334 | ||
e0b582ec | 335 | if (!cpu_possible(cpu)) { |
73e753a5 KH |
336 | printk(KERN_ERR "can't online cpu %d because it is not " |
337 | "configured as may-hotadd at boot time\n", cpu); | |
87d5e023 | 338 | #if defined(CONFIG_IA64) |
73e753a5 KH |
339 | printk(KERN_ERR "please check additional_cpus= boot " |
340 | "parameter\n"); | |
341 | #endif | |
342 | return -EINVAL; | |
343 | } | |
e3920fb4 | 344 | |
cf23422b | 345 | #ifdef CONFIG_MEMORY_HOTPLUG |
346 | nid = cpu_to_node(cpu); | |
347 | if (!node_online(nid)) { | |
348 | err = mem_online_node(nid); | |
349 | if (err) | |
350 | return err; | |
351 | } | |
352 | ||
353 | pgdat = NODE_DATA(nid); | |
354 | if (!pgdat) { | |
355 | printk(KERN_ERR | |
356 | "Can't online cpu %d due to NULL pgdat\n", cpu); | |
357 | return -ENOMEM; | |
358 | } | |
359 | ||
360 | if (pgdat->node_zonelists->_zonerefs->zone == NULL) | |
1f522509 | 361 | build_all_zonelists(NULL); |
cf23422b | 362 | #endif |
363 | ||
d221938c | 364 | cpu_maps_update_begin(); |
e761b772 MK |
365 | |
366 | if (cpu_hotplug_disabled) { | |
e3920fb4 | 367 | err = -EBUSY; |
e761b772 MK |
368 | goto out; |
369 | } | |
370 | ||
371 | err = _cpu_up(cpu, 0); | |
372 | ||
e761b772 | 373 | out: |
d221938c | 374 | cpu_maps_update_done(); |
e3920fb4 RW |
375 | return err; |
376 | } | |
377 | ||
f3de4be9 | 378 | #ifdef CONFIG_PM_SLEEP_SMP |
e0b582ec | 379 | static cpumask_var_t frozen_cpus; |
e3920fb4 RW |
380 | |
381 | int disable_nonboot_cpus(void) | |
382 | { | |
69575d38 | 383 | int cpu, first_cpu, error; |
e3920fb4 | 384 | |
d221938c | 385 | cpu_maps_update_begin(); |
e0b582ec | 386 | first_cpu = cpumask_first(cpu_online_mask); |
9ee349ad XF |
387 | /* |
388 | * We take down all of the non-boot CPUs in one shot to avoid races | |
e3920fb4 RW |
389 | * with the userspace trying to use the CPU hotplug at the same time |
390 | */ | |
e0b582ec | 391 | cpumask_clear(frozen_cpus); |
6ad4c188 | 392 | |
e3920fb4 RW |
393 | printk("Disabling non-boot CPUs ...\n"); |
394 | for_each_online_cpu(cpu) { | |
395 | if (cpu == first_cpu) | |
396 | continue; | |
8bb78442 | 397 | error = _cpu_down(cpu, 1); |
feae3203 | 398 | if (!error) |
e0b582ec | 399 | cpumask_set_cpu(cpu, frozen_cpus); |
feae3203 | 400 | else { |
e3920fb4 RW |
401 | printk(KERN_ERR "Error taking CPU%d down: %d\n", |
402 | cpu, error); | |
403 | break; | |
404 | } | |
405 | } | |
86886e55 | 406 | |
e3920fb4 RW |
407 | if (!error) { |
408 | BUG_ON(num_online_cpus() > 1); | |
409 | /* Make sure the CPUs won't be enabled by someone else */ | |
410 | cpu_hotplug_disabled = 1; | |
411 | } else { | |
e1d9fd2e | 412 | printk(KERN_ERR "Non-boot CPUs are not disabled\n"); |
e3920fb4 | 413 | } |
d221938c | 414 | cpu_maps_update_done(); |
e3920fb4 RW |
415 | return error; |
416 | } | |
417 | ||
d0af9eed SS |
418 | void __weak arch_enable_nonboot_cpus_begin(void) |
419 | { | |
420 | } | |
421 | ||
422 | void __weak arch_enable_nonboot_cpus_end(void) | |
423 | { | |
424 | } | |
425 | ||
fa7303e2 | 426 | void __ref enable_nonboot_cpus(void) |
e3920fb4 RW |
427 | { |
428 | int cpu, error; | |
429 | ||
430 | /* Allow everyone to use the CPU hotplug again */ | |
d221938c | 431 | cpu_maps_update_begin(); |
e3920fb4 | 432 | cpu_hotplug_disabled = 0; |
e0b582ec | 433 | if (cpumask_empty(frozen_cpus)) |
1d64b9cb | 434 | goto out; |
e3920fb4 RW |
435 | |
436 | printk("Enabling non-boot CPUs ...\n"); | |
d0af9eed SS |
437 | |
438 | arch_enable_nonboot_cpus_begin(); | |
439 | ||
e0b582ec | 440 | for_each_cpu(cpu, frozen_cpus) { |
8bb78442 | 441 | error = _cpu_up(cpu, 1); |
e3920fb4 RW |
442 | if (!error) { |
443 | printk("CPU%d is up\n", cpu); | |
444 | continue; | |
445 | } | |
1d64b9cb | 446 | printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error); |
e3920fb4 | 447 | } |
d0af9eed SS |
448 | |
449 | arch_enable_nonboot_cpus_end(); | |
450 | ||
e0b582ec | 451 | cpumask_clear(frozen_cpus); |
1d64b9cb | 452 | out: |
d221938c | 453 | cpu_maps_update_done(); |
1da177e4 | 454 | } |
e0b582ec RR |
455 | |
456 | static int alloc_frozen_cpus(void) | |
457 | { | |
458 | if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO)) | |
459 | return -ENOMEM; | |
460 | return 0; | |
461 | } | |
462 | core_initcall(alloc_frozen_cpus); | |
f3de4be9 | 463 | #endif /* CONFIG_PM_SLEEP_SMP */ |
68f4f1ec | 464 | |
e545a614 MS |
465 | /** |
466 | * notify_cpu_starting(cpu) - call the CPU_STARTING notifiers | |
467 | * @cpu: cpu that just started | |
468 | * | |
469 | * This function calls the cpu_chain notifiers with CPU_STARTING. | |
470 | * It must be called by the arch code on the new cpu, before the new cpu | |
471 | * enables interrupts and before the "boot" cpu returns from __cpu_up(). | |
472 | */ | |
84196414 | 473 | void __cpuinit notify_cpu_starting(unsigned int cpu) |
e545a614 MS |
474 | { |
475 | unsigned long val = CPU_STARTING; | |
476 | ||
477 | #ifdef CONFIG_PM_SLEEP_SMP | |
e0b582ec | 478 | if (frozen_cpus != NULL && cpumask_test_cpu(cpu, frozen_cpus)) |
e545a614 MS |
479 | val = CPU_STARTING_FROZEN; |
480 | #endif /* CONFIG_PM_SLEEP_SMP */ | |
481 | raw_notifier_call_chain(&cpu_chain, val, (void *)(long)cpu); | |
482 | } | |
483 | ||
68f4f1ec | 484 | #endif /* CONFIG_SMP */ |
b8d317d1 | 485 | |
e56b3bc7 LT |
486 | /* |
487 | * cpu_bit_bitmap[] is a special, "compressed" data structure that | |
488 | * represents all NR_CPUS bits binary values of 1<<nr. | |
489 | * | |
e0b582ec | 490 | * It is used by cpumask_of() to get a constant address to a CPU |
e56b3bc7 LT |
491 | * mask value that has a single bit set only. |
492 | */ | |
b8d317d1 | 493 | |
e56b3bc7 LT |
494 | /* cpu_bit_bitmap[0] is empty - so we can back into it */ |
495 | #define MASK_DECLARE_1(x) [x+1][0] = 1UL << (x) | |
496 | #define MASK_DECLARE_2(x) MASK_DECLARE_1(x), MASK_DECLARE_1(x+1) | |
497 | #define MASK_DECLARE_4(x) MASK_DECLARE_2(x), MASK_DECLARE_2(x+2) | |
498 | #define MASK_DECLARE_8(x) MASK_DECLARE_4(x), MASK_DECLARE_4(x+4) | |
b8d317d1 | 499 | |
e56b3bc7 LT |
500 | const unsigned long cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)] = { |
501 | ||
502 | MASK_DECLARE_8(0), MASK_DECLARE_8(8), | |
503 | MASK_DECLARE_8(16), MASK_DECLARE_8(24), | |
504 | #if BITS_PER_LONG > 32 | |
505 | MASK_DECLARE_8(32), MASK_DECLARE_8(40), | |
506 | MASK_DECLARE_8(48), MASK_DECLARE_8(56), | |
b8d317d1 MT |
507 | #endif |
508 | }; | |
e56b3bc7 | 509 | EXPORT_SYMBOL_GPL(cpu_bit_bitmap); |
2d3854a3 RR |
510 | |
511 | const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL; | |
512 | EXPORT_SYMBOL(cpu_all_bits); | |
b3199c02 RR |
513 | |
514 | #ifdef CONFIG_INIT_ALL_POSSIBLE | |
515 | static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly | |
516 | = CPU_BITS_ALL; | |
517 | #else | |
518 | static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly; | |
519 | #endif | |
520 | const struct cpumask *const cpu_possible_mask = to_cpumask(cpu_possible_bits); | |
521 | EXPORT_SYMBOL(cpu_possible_mask); | |
522 | ||
523 | static DECLARE_BITMAP(cpu_online_bits, CONFIG_NR_CPUS) __read_mostly; | |
524 | const struct cpumask *const cpu_online_mask = to_cpumask(cpu_online_bits); | |
525 | EXPORT_SYMBOL(cpu_online_mask); | |
526 | ||
527 | static DECLARE_BITMAP(cpu_present_bits, CONFIG_NR_CPUS) __read_mostly; | |
528 | const struct cpumask *const cpu_present_mask = to_cpumask(cpu_present_bits); | |
529 | EXPORT_SYMBOL(cpu_present_mask); | |
530 | ||
531 | static DECLARE_BITMAP(cpu_active_bits, CONFIG_NR_CPUS) __read_mostly; | |
532 | const struct cpumask *const cpu_active_mask = to_cpumask(cpu_active_bits); | |
533 | EXPORT_SYMBOL(cpu_active_mask); | |
3fa41520 RR |
534 | |
535 | void set_cpu_possible(unsigned int cpu, bool possible) | |
536 | { | |
537 | if (possible) | |
538 | cpumask_set_cpu(cpu, to_cpumask(cpu_possible_bits)); | |
539 | else | |
540 | cpumask_clear_cpu(cpu, to_cpumask(cpu_possible_bits)); | |
541 | } | |
542 | ||
543 | void set_cpu_present(unsigned int cpu, bool present) | |
544 | { | |
545 | if (present) | |
546 | cpumask_set_cpu(cpu, to_cpumask(cpu_present_bits)); | |
547 | else | |
548 | cpumask_clear_cpu(cpu, to_cpumask(cpu_present_bits)); | |
549 | } | |
550 | ||
551 | void set_cpu_online(unsigned int cpu, bool online) | |
552 | { | |
553 | if (online) | |
554 | cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits)); | |
555 | else | |
556 | cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits)); | |
557 | } | |
558 | ||
559 | void set_cpu_active(unsigned int cpu, bool active) | |
560 | { | |
561 | if (active) | |
562 | cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits)); | |
563 | else | |
564 | cpumask_clear_cpu(cpu, to_cpumask(cpu_active_bits)); | |
565 | } | |
566 | ||
567 | void init_cpu_present(const struct cpumask *src) | |
568 | { | |
569 | cpumask_copy(to_cpumask(cpu_present_bits), src); | |
570 | } | |
571 | ||
572 | void init_cpu_possible(const struct cpumask *src) | |
573 | { | |
574 | cpumask_copy(to_cpumask(cpu_possible_bits), src); | |
575 | } | |
576 | ||
577 | void init_cpu_online(const struct cpumask *src) | |
578 | { | |
579 | cpumask_copy(to_cpumask(cpu_online_bits), src); | |
580 | } |