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> | |
3f07c014 | 10 | #include <linux/sched/signal.h> |
ef8bd77f | 11 | #include <linux/sched/hotplug.h> |
29930025 | 12 | #include <linux/sched/task.h> |
1da177e4 LT |
13 | #include <linux/unistd.h> |
14 | #include <linux/cpu.h> | |
cb79295e AV |
15 | #include <linux/oom.h> |
16 | #include <linux/rcupdate.h> | |
9984de1a | 17 | #include <linux/export.h> |
e4cc2f87 | 18 | #include <linux/bug.h> |
1da177e4 LT |
19 | #include <linux/kthread.h> |
20 | #include <linux/stop_machine.h> | |
81615b62 | 21 | #include <linux/mutex.h> |
5a0e3ad6 | 22 | #include <linux/gfp.h> |
79cfbdfa | 23 | #include <linux/suspend.h> |
a19423b9 | 24 | #include <linux/lockdep.h> |
345527b1 | 25 | #include <linux/tick.h> |
a8994181 | 26 | #include <linux/irq.h> |
941154bd | 27 | #include <linux/nmi.h> |
4cb28ced | 28 | #include <linux/smpboot.h> |
e6d4989a | 29 | #include <linux/relay.h> |
6731d4f1 | 30 | #include <linux/slab.h> |
fc8dffd3 | 31 | #include <linux/percpu-rwsem.h> |
cff7d378 | 32 | |
bb3632c6 | 33 | #include <trace/events/power.h> |
cff7d378 TG |
34 | #define CREATE_TRACE_POINTS |
35 | #include <trace/events/cpuhp.h> | |
1da177e4 | 36 | |
38498a67 TG |
37 | #include "smpboot.h" |
38 | ||
cff7d378 TG |
39 | /** |
40 | * cpuhp_cpu_state - Per cpu hotplug state storage | |
41 | * @state: The current cpu state | |
42 | * @target: The target state | |
4cb28ced TG |
43 | * @thread: Pointer to the hotplug thread |
44 | * @should_run: Thread should execute | |
3b9d6da6 | 45 | * @rollback: Perform a rollback |
a724632c TG |
46 | * @single: Single callback invocation |
47 | * @bringup: Single callback bringup or teardown selector | |
48 | * @cb_state: The state for a single callback (install/uninstall) | |
4cb28ced | 49 | * @result: Result of the operation |
5ebe7742 PZ |
50 | * @done_up: Signal completion to the issuer of the task for cpu-up |
51 | * @done_down: Signal completion to the issuer of the task for cpu-down | |
cff7d378 TG |
52 | */ |
53 | struct cpuhp_cpu_state { | |
54 | enum cpuhp_state state; | |
55 | enum cpuhp_state target; | |
1db49484 | 56 | enum cpuhp_state fail; |
4cb28ced TG |
57 | #ifdef CONFIG_SMP |
58 | struct task_struct *thread; | |
59 | bool should_run; | |
3b9d6da6 | 60 | bool rollback; |
a724632c TG |
61 | bool single; |
62 | bool bringup; | |
cf392d10 | 63 | struct hlist_node *node; |
4dddfb5f | 64 | struct hlist_node *last; |
4cb28ced | 65 | enum cpuhp_state cb_state; |
4cb28ced | 66 | int result; |
5ebe7742 PZ |
67 | struct completion done_up; |
68 | struct completion done_down; | |
4cb28ced | 69 | #endif |
cff7d378 TG |
70 | }; |
71 | ||
1db49484 PZ |
72 | static DEFINE_PER_CPU(struct cpuhp_cpu_state, cpuhp_state) = { |
73 | .fail = CPUHP_INVALID, | |
74 | }; | |
cff7d378 | 75 | |
49dfe2a6 | 76 | #if defined(CONFIG_LOCKDEP) && defined(CONFIG_SMP) |
5f4b55e1 PZ |
77 | static struct lockdep_map cpuhp_state_up_map = |
78 | STATIC_LOCKDEP_MAP_INIT("cpuhp_state-up", &cpuhp_state_up_map); | |
79 | static struct lockdep_map cpuhp_state_down_map = | |
80 | STATIC_LOCKDEP_MAP_INIT("cpuhp_state-down", &cpuhp_state_down_map); | |
81 | ||
82 | ||
76dc6c09 | 83 | static inline void cpuhp_lock_acquire(bool bringup) |
5f4b55e1 PZ |
84 | { |
85 | lock_map_acquire(bringup ? &cpuhp_state_up_map : &cpuhp_state_down_map); | |
86 | } | |
87 | ||
76dc6c09 | 88 | static inline void cpuhp_lock_release(bool bringup) |
5f4b55e1 PZ |
89 | { |
90 | lock_map_release(bringup ? &cpuhp_state_up_map : &cpuhp_state_down_map); | |
91 | } | |
92 | #else | |
93 | ||
76dc6c09 MM |
94 | static inline void cpuhp_lock_acquire(bool bringup) { } |
95 | static inline void cpuhp_lock_release(bool bringup) { } | |
5f4b55e1 | 96 | |
49dfe2a6 TG |
97 | #endif |
98 | ||
cff7d378 TG |
99 | /** |
100 | * cpuhp_step - Hotplug state machine step | |
101 | * @name: Name of the step | |
102 | * @startup: Startup function of the step | |
103 | * @teardown: Teardown function of the step | |
104 | * @skip_onerr: Do not invoke the functions on error rollback | |
105 | * Will go away once the notifiers are gone | |
757c989b | 106 | * @cant_stop: Bringup/teardown can't be stopped at this step |
cff7d378 TG |
107 | */ |
108 | struct cpuhp_step { | |
cf392d10 TG |
109 | const char *name; |
110 | union { | |
3c1627e9 TG |
111 | int (*single)(unsigned int cpu); |
112 | int (*multi)(unsigned int cpu, | |
113 | struct hlist_node *node); | |
114 | } startup; | |
cf392d10 | 115 | union { |
3c1627e9 TG |
116 | int (*single)(unsigned int cpu); |
117 | int (*multi)(unsigned int cpu, | |
118 | struct hlist_node *node); | |
119 | } teardown; | |
cf392d10 TG |
120 | struct hlist_head list; |
121 | bool skip_onerr; | |
122 | bool cant_stop; | |
123 | bool multi_instance; | |
cff7d378 TG |
124 | }; |
125 | ||
98f8cdce | 126 | static DEFINE_MUTEX(cpuhp_state_mutex); |
17a2f1ce | 127 | static struct cpuhp_step cpuhp_hp_states[]; |
cff7d378 | 128 | |
a724632c TG |
129 | static struct cpuhp_step *cpuhp_get_step(enum cpuhp_state state) |
130 | { | |
17a2f1ce | 131 | return cpuhp_hp_states + state; |
a724632c TG |
132 | } |
133 | ||
cff7d378 TG |
134 | /** |
135 | * cpuhp_invoke_callback _ Invoke the callbacks for a given state | |
136 | * @cpu: The cpu for which the callback should be invoked | |
96abb968 | 137 | * @state: The state to do callbacks for |
a724632c | 138 | * @bringup: True if the bringup callback should be invoked |
96abb968 PZ |
139 | * @node: For multi-instance, do a single entry callback for install/remove |
140 | * @lastp: For multi-instance rollback, remember how far we got | |
cff7d378 | 141 | * |
cf392d10 | 142 | * Called from cpu hotplug and from the state register machinery. |
cff7d378 | 143 | */ |
a724632c | 144 | static int cpuhp_invoke_callback(unsigned int cpu, enum cpuhp_state state, |
96abb968 PZ |
145 | bool bringup, struct hlist_node *node, |
146 | struct hlist_node **lastp) | |
cff7d378 TG |
147 | { |
148 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
a724632c | 149 | struct cpuhp_step *step = cpuhp_get_step(state); |
cf392d10 TG |
150 | int (*cbm)(unsigned int cpu, struct hlist_node *node); |
151 | int (*cb)(unsigned int cpu); | |
152 | int ret, cnt; | |
153 | ||
1db49484 PZ |
154 | if (st->fail == state) { |
155 | st->fail = CPUHP_INVALID; | |
156 | ||
157 | if (!(bringup ? step->startup.single : step->teardown.single)) | |
158 | return 0; | |
159 | ||
160 | return -EAGAIN; | |
161 | } | |
162 | ||
cf392d10 | 163 | if (!step->multi_instance) { |
96abb968 | 164 | WARN_ON_ONCE(lastp && *lastp); |
3c1627e9 | 165 | cb = bringup ? step->startup.single : step->teardown.single; |
cf392d10 TG |
166 | if (!cb) |
167 | return 0; | |
a724632c | 168 | trace_cpuhp_enter(cpu, st->target, state, cb); |
cff7d378 | 169 | ret = cb(cpu); |
a724632c | 170 | trace_cpuhp_exit(cpu, st->state, state, ret); |
cf392d10 TG |
171 | return ret; |
172 | } | |
3c1627e9 | 173 | cbm = bringup ? step->startup.multi : step->teardown.multi; |
cf392d10 TG |
174 | if (!cbm) |
175 | return 0; | |
176 | ||
177 | /* Single invocation for instance add/remove */ | |
178 | if (node) { | |
96abb968 | 179 | WARN_ON_ONCE(lastp && *lastp); |
cf392d10 TG |
180 | trace_cpuhp_multi_enter(cpu, st->target, state, cbm, node); |
181 | ret = cbm(cpu, node); | |
182 | trace_cpuhp_exit(cpu, st->state, state, ret); | |
183 | return ret; | |
184 | } | |
185 | ||
186 | /* State transition. Invoke on all instances */ | |
187 | cnt = 0; | |
188 | hlist_for_each(node, &step->list) { | |
96abb968 PZ |
189 | if (lastp && node == *lastp) |
190 | break; | |
191 | ||
cf392d10 TG |
192 | trace_cpuhp_multi_enter(cpu, st->target, state, cbm, node); |
193 | ret = cbm(cpu, node); | |
194 | trace_cpuhp_exit(cpu, st->state, state, ret); | |
96abb968 PZ |
195 | if (ret) { |
196 | if (!lastp) | |
197 | goto err; | |
198 | ||
199 | *lastp = node; | |
200 | return ret; | |
201 | } | |
cf392d10 TG |
202 | cnt++; |
203 | } | |
96abb968 PZ |
204 | if (lastp) |
205 | *lastp = NULL; | |
cf392d10 TG |
206 | return 0; |
207 | err: | |
208 | /* Rollback the instances if one failed */ | |
3c1627e9 | 209 | cbm = !bringup ? step->startup.multi : step->teardown.multi; |
cf392d10 TG |
210 | if (!cbm) |
211 | return ret; | |
212 | ||
213 | hlist_for_each(node, &step->list) { | |
214 | if (!cnt--) | |
215 | break; | |
724a8688 PZ |
216 | |
217 | trace_cpuhp_multi_enter(cpu, st->target, state, cbm, node); | |
218 | ret = cbm(cpu, node); | |
219 | trace_cpuhp_exit(cpu, st->state, state, ret); | |
220 | /* | |
221 | * Rollback must not fail, | |
222 | */ | |
223 | WARN_ON_ONCE(ret); | |
cff7d378 TG |
224 | } |
225 | return ret; | |
226 | } | |
227 | ||
98a79d6a | 228 | #ifdef CONFIG_SMP |
fcb3029a AB |
229 | static bool cpuhp_is_ap_state(enum cpuhp_state state) |
230 | { | |
231 | /* | |
232 | * The extra check for CPUHP_TEARDOWN_CPU is only for documentation | |
233 | * purposes as that state is handled explicitly in cpu_down. | |
234 | */ | |
235 | return state > CPUHP_BRINGUP_CPU && state != CPUHP_TEARDOWN_CPU; | |
236 | } | |
237 | ||
5ebe7742 PZ |
238 | static inline void wait_for_ap_thread(struct cpuhp_cpu_state *st, bool bringup) |
239 | { | |
240 | struct completion *done = bringup ? &st->done_up : &st->done_down; | |
241 | wait_for_completion(done); | |
242 | } | |
243 | ||
244 | static inline void complete_ap_thread(struct cpuhp_cpu_state *st, bool bringup) | |
245 | { | |
246 | struct completion *done = bringup ? &st->done_up : &st->done_down; | |
247 | complete(done); | |
248 | } | |
249 | ||
250 | /* | |
251 | * The former STARTING/DYING states, ran with IRQs disabled and must not fail. | |
252 | */ | |
253 | static bool cpuhp_is_atomic_state(enum cpuhp_state state) | |
254 | { | |
255 | return CPUHP_AP_IDLE_DEAD <= state && state < CPUHP_AP_ONLINE; | |
256 | } | |
257 | ||
b3199c02 | 258 | /* Serializes the updates to cpu_online_mask, cpu_present_mask */ |
aa953877 | 259 | static DEFINE_MUTEX(cpu_add_remove_lock); |
090e77c3 TG |
260 | bool cpuhp_tasks_frozen; |
261 | EXPORT_SYMBOL_GPL(cpuhp_tasks_frozen); | |
1da177e4 | 262 | |
79a6cdeb | 263 | /* |
93ae4f97 SB |
264 | * The following two APIs (cpu_maps_update_begin/done) must be used when |
265 | * attempting to serialize the updates to cpu_online_mask & cpu_present_mask. | |
79a6cdeb LJ |
266 | */ |
267 | void cpu_maps_update_begin(void) | |
268 | { | |
269 | mutex_lock(&cpu_add_remove_lock); | |
270 | } | |
271 | ||
272 | void cpu_maps_update_done(void) | |
273 | { | |
274 | mutex_unlock(&cpu_add_remove_lock); | |
275 | } | |
1da177e4 | 276 | |
fc8dffd3 TG |
277 | /* |
278 | * If set, cpu_up and cpu_down will return -EBUSY and do nothing. | |
e3920fb4 RW |
279 | * Should always be manipulated under cpu_add_remove_lock |
280 | */ | |
281 | static int cpu_hotplug_disabled; | |
282 | ||
79a6cdeb LJ |
283 | #ifdef CONFIG_HOTPLUG_CPU |
284 | ||
fc8dffd3 | 285 | DEFINE_STATIC_PERCPU_RWSEM(cpu_hotplug_lock); |
a19423b9 | 286 | |
8f553c49 | 287 | void cpus_read_lock(void) |
a9d9baa1 | 288 | { |
fc8dffd3 | 289 | percpu_down_read(&cpu_hotplug_lock); |
a9d9baa1 | 290 | } |
8f553c49 | 291 | EXPORT_SYMBOL_GPL(cpus_read_lock); |
90d45d17 | 292 | |
8f553c49 | 293 | void cpus_read_unlock(void) |
a9d9baa1 | 294 | { |
fc8dffd3 | 295 | percpu_up_read(&cpu_hotplug_lock); |
a9d9baa1 | 296 | } |
8f553c49 | 297 | EXPORT_SYMBOL_GPL(cpus_read_unlock); |
a9d9baa1 | 298 | |
8f553c49 | 299 | void cpus_write_lock(void) |
d221938c | 300 | { |
fc8dffd3 | 301 | percpu_down_write(&cpu_hotplug_lock); |
d221938c | 302 | } |
87af9e7f | 303 | |
8f553c49 | 304 | void cpus_write_unlock(void) |
d221938c | 305 | { |
fc8dffd3 | 306 | percpu_up_write(&cpu_hotplug_lock); |
d221938c GS |
307 | } |
308 | ||
fc8dffd3 | 309 | void lockdep_assert_cpus_held(void) |
d221938c | 310 | { |
fc8dffd3 | 311 | percpu_rwsem_assert_held(&cpu_hotplug_lock); |
d221938c | 312 | } |
79a6cdeb | 313 | |
16e53dbf SB |
314 | /* |
315 | * Wait for currently running CPU hotplug operations to complete (if any) and | |
316 | * disable future CPU hotplug (from sysfs). The 'cpu_add_remove_lock' protects | |
317 | * the 'cpu_hotplug_disabled' flag. The same lock is also acquired by the | |
318 | * hotplug path before performing hotplug operations. So acquiring that lock | |
319 | * guarantees mutual exclusion from any currently running hotplug operations. | |
320 | */ | |
321 | void cpu_hotplug_disable(void) | |
322 | { | |
323 | cpu_maps_update_begin(); | |
89af7ba5 | 324 | cpu_hotplug_disabled++; |
16e53dbf SB |
325 | cpu_maps_update_done(); |
326 | } | |
32145c46 | 327 | EXPORT_SYMBOL_GPL(cpu_hotplug_disable); |
16e53dbf | 328 | |
01b41159 LW |
329 | static void __cpu_hotplug_enable(void) |
330 | { | |
331 | if (WARN_ONCE(!cpu_hotplug_disabled, "Unbalanced cpu hotplug enable\n")) | |
332 | return; | |
333 | cpu_hotplug_disabled--; | |
334 | } | |
335 | ||
16e53dbf SB |
336 | void cpu_hotplug_enable(void) |
337 | { | |
338 | cpu_maps_update_begin(); | |
01b41159 | 339 | __cpu_hotplug_enable(); |
16e53dbf SB |
340 | cpu_maps_update_done(); |
341 | } | |
32145c46 | 342 | EXPORT_SYMBOL_GPL(cpu_hotplug_enable); |
b9d10be7 | 343 | #endif /* CONFIG_HOTPLUG_CPU */ |
79a6cdeb | 344 | |
4dddfb5f PZ |
345 | static inline enum cpuhp_state |
346 | cpuhp_set_state(struct cpuhp_cpu_state *st, enum cpuhp_state target) | |
347 | { | |
348 | enum cpuhp_state prev_state = st->state; | |
349 | ||
350 | st->rollback = false; | |
351 | st->last = NULL; | |
352 | ||
353 | st->target = target; | |
354 | st->single = false; | |
355 | st->bringup = st->state < target; | |
356 | ||
357 | return prev_state; | |
358 | } | |
359 | ||
360 | static inline void | |
361 | cpuhp_reset_state(struct cpuhp_cpu_state *st, enum cpuhp_state prev_state) | |
362 | { | |
363 | st->rollback = true; | |
364 | ||
365 | /* | |
366 | * If we have st->last we need to undo partial multi_instance of this | |
367 | * state first. Otherwise start undo at the previous state. | |
368 | */ | |
369 | if (!st->last) { | |
370 | if (st->bringup) | |
371 | st->state--; | |
372 | else | |
373 | st->state++; | |
374 | } | |
375 | ||
376 | st->target = prev_state; | |
377 | st->bringup = !st->bringup; | |
378 | } | |
379 | ||
380 | /* Regular hotplug invocation of the AP hotplug thread */ | |
381 | static void __cpuhp_kick_ap(struct cpuhp_cpu_state *st) | |
382 | { | |
383 | if (!st->single && st->state == st->target) | |
384 | return; | |
385 | ||
386 | st->result = 0; | |
387 | /* | |
388 | * Make sure the above stores are visible before should_run becomes | |
389 | * true. Paired with the mb() above in cpuhp_thread_fun() | |
390 | */ | |
391 | smp_mb(); | |
392 | st->should_run = true; | |
393 | wake_up_process(st->thread); | |
5ebe7742 | 394 | wait_for_ap_thread(st, st->bringup); |
4dddfb5f PZ |
395 | } |
396 | ||
397 | static int cpuhp_kick_ap(struct cpuhp_cpu_state *st, enum cpuhp_state target) | |
398 | { | |
399 | enum cpuhp_state prev_state; | |
400 | int ret; | |
401 | ||
402 | prev_state = cpuhp_set_state(st, target); | |
403 | __cpuhp_kick_ap(st); | |
404 | if ((ret = st->result)) { | |
405 | cpuhp_reset_state(st, prev_state); | |
406 | __cpuhp_kick_ap(st); | |
407 | } | |
408 | ||
409 | return ret; | |
410 | } | |
9cd4f1a4 | 411 | |
8df3e07e TG |
412 | static int bringup_wait_for_ap(unsigned int cpu) |
413 | { | |
414 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
415 | ||
9cd4f1a4 | 416 | /* Wait for the CPU to reach CPUHP_AP_ONLINE_IDLE */ |
5ebe7742 | 417 | wait_for_ap_thread(st, true); |
dea1d0f5 TG |
418 | if (WARN_ON_ONCE((!cpu_online(cpu)))) |
419 | return -ECANCELED; | |
9cd4f1a4 TG |
420 | |
421 | /* Unpark the stopper thread and the hotplug thread of the target cpu */ | |
422 | stop_machine_unpark(cpu); | |
423 | kthread_unpark(st->thread); | |
424 | ||
4dddfb5f PZ |
425 | if (st->target <= CPUHP_AP_ONLINE_IDLE) |
426 | return 0; | |
427 | ||
428 | return cpuhp_kick_ap(st, st->target); | |
8df3e07e TG |
429 | } |
430 | ||
ba997462 TG |
431 | static int bringup_cpu(unsigned int cpu) |
432 | { | |
433 | struct task_struct *idle = idle_thread_get(cpu); | |
434 | int ret; | |
435 | ||
aa877175 BO |
436 | /* |
437 | * Some architectures have to walk the irq descriptors to | |
438 | * setup the vector space for the cpu which comes online. | |
439 | * Prevent irq alloc/free across the bringup. | |
440 | */ | |
441 | irq_lock_sparse(); | |
442 | ||
ba997462 TG |
443 | /* Arch-specific enabling code. */ |
444 | ret = __cpu_up(cpu, idle); | |
aa877175 | 445 | irq_unlock_sparse(); |
530e9b76 | 446 | if (ret) |
ba997462 | 447 | return ret; |
9cd4f1a4 | 448 | return bringup_wait_for_ap(cpu); |
ba997462 TG |
449 | } |
450 | ||
2e1a3483 TG |
451 | /* |
452 | * Hotplug state machine related functions | |
453 | */ | |
2e1a3483 | 454 | |
a724632c | 455 | static void undo_cpu_up(unsigned int cpu, struct cpuhp_cpu_state *st) |
2e1a3483 TG |
456 | { |
457 | for (st->state--; st->state > st->target; st->state--) { | |
a724632c | 458 | struct cpuhp_step *step = cpuhp_get_step(st->state); |
2e1a3483 TG |
459 | |
460 | if (!step->skip_onerr) | |
96abb968 | 461 | cpuhp_invoke_callback(cpu, st->state, false, NULL, NULL); |
2e1a3483 TG |
462 | } |
463 | } | |
464 | ||
465 | static int cpuhp_up_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st, | |
a724632c | 466 | enum cpuhp_state target) |
2e1a3483 TG |
467 | { |
468 | enum cpuhp_state prev_state = st->state; | |
469 | int ret = 0; | |
470 | ||
471 | while (st->state < target) { | |
2e1a3483 | 472 | st->state++; |
96abb968 | 473 | ret = cpuhp_invoke_callback(cpu, st->state, true, NULL, NULL); |
2e1a3483 TG |
474 | if (ret) { |
475 | st->target = prev_state; | |
a724632c | 476 | undo_cpu_up(cpu, st); |
2e1a3483 TG |
477 | break; |
478 | } | |
479 | } | |
480 | return ret; | |
481 | } | |
482 | ||
4cb28ced TG |
483 | /* |
484 | * The cpu hotplug threads manage the bringup and teardown of the cpus | |
485 | */ | |
486 | static void cpuhp_create(unsigned int cpu) | |
487 | { | |
488 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
489 | ||
5ebe7742 PZ |
490 | init_completion(&st->done_up); |
491 | init_completion(&st->done_down); | |
4cb28ced TG |
492 | } |
493 | ||
494 | static int cpuhp_should_run(unsigned int cpu) | |
495 | { | |
496 | struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); | |
497 | ||
498 | return st->should_run; | |
499 | } | |
500 | ||
4cb28ced TG |
501 | /* |
502 | * Execute teardown/startup callbacks on the plugged cpu. Also used to invoke | |
503 | * callbacks when a state gets [un]installed at runtime. | |
4dddfb5f PZ |
504 | * |
505 | * Each invocation of this function by the smpboot thread does a single AP | |
506 | * state callback. | |
507 | * | |
508 | * It has 3 modes of operation: | |
509 | * - single: runs st->cb_state | |
510 | * - up: runs ++st->state, while st->state < st->target | |
511 | * - down: runs st->state--, while st->state > st->target | |
512 | * | |
513 | * When complete or on error, should_run is cleared and the completion is fired. | |
4cb28ced TG |
514 | */ |
515 | static void cpuhp_thread_fun(unsigned int cpu) | |
516 | { | |
517 | struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); | |
4dddfb5f PZ |
518 | bool bringup = st->bringup; |
519 | enum cpuhp_state state; | |
4cb28ced TG |
520 | |
521 | /* | |
4dddfb5f PZ |
522 | * ACQUIRE for the cpuhp_should_run() load of ->should_run. Ensures |
523 | * that if we see ->should_run we also see the rest of the state. | |
4cb28ced TG |
524 | */ |
525 | smp_mb(); | |
4cb28ced | 526 | |
4dddfb5f PZ |
527 | if (WARN_ON_ONCE(!st->should_run)) |
528 | return; | |
4cb28ced | 529 | |
5f4b55e1 | 530 | cpuhp_lock_acquire(bringup); |
4dddfb5f | 531 | |
a724632c | 532 | if (st->single) { |
4dddfb5f PZ |
533 | state = st->cb_state; |
534 | st->should_run = false; | |
535 | } else { | |
536 | if (bringup) { | |
537 | st->state++; | |
538 | state = st->state; | |
539 | st->should_run = (st->state < st->target); | |
540 | WARN_ON_ONCE(st->state > st->target); | |
4cb28ced | 541 | } else { |
4dddfb5f PZ |
542 | state = st->state; |
543 | st->state--; | |
544 | st->should_run = (st->state > st->target); | |
545 | WARN_ON_ONCE(st->state < st->target); | |
4cb28ced | 546 | } |
4dddfb5f PZ |
547 | } |
548 | ||
549 | WARN_ON_ONCE(!cpuhp_is_ap_state(state)); | |
550 | ||
551 | if (st->rollback) { | |
552 | struct cpuhp_step *step = cpuhp_get_step(state); | |
553 | if (step->skip_onerr) | |
554 | goto next; | |
555 | } | |
556 | ||
557 | if (cpuhp_is_atomic_state(state)) { | |
558 | local_irq_disable(); | |
559 | st->result = cpuhp_invoke_callback(cpu, state, bringup, st->node, &st->last); | |
560 | local_irq_enable(); | |
3b9d6da6 | 561 | |
4dddfb5f PZ |
562 | /* |
563 | * STARTING/DYING must not fail! | |
564 | */ | |
565 | WARN_ON_ONCE(st->result); | |
4cb28ced | 566 | } else { |
4dddfb5f PZ |
567 | st->result = cpuhp_invoke_callback(cpu, state, bringup, st->node, &st->last); |
568 | } | |
569 | ||
570 | if (st->result) { | |
571 | /* | |
572 | * If we fail on a rollback, we're up a creek without no | |
573 | * paddle, no way forward, no way back. We loose, thanks for | |
574 | * playing. | |
575 | */ | |
576 | WARN_ON_ONCE(st->rollback); | |
577 | st->should_run = false; | |
4cb28ced | 578 | } |
4dddfb5f PZ |
579 | |
580 | next: | |
5f4b55e1 | 581 | cpuhp_lock_release(bringup); |
4dddfb5f PZ |
582 | |
583 | if (!st->should_run) | |
5ebe7742 | 584 | complete_ap_thread(st, bringup); |
4cb28ced TG |
585 | } |
586 | ||
587 | /* Invoke a single callback on a remote cpu */ | |
a724632c | 588 | static int |
cf392d10 TG |
589 | cpuhp_invoke_ap_callback(int cpu, enum cpuhp_state state, bool bringup, |
590 | struct hlist_node *node) | |
4cb28ced TG |
591 | { |
592 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
4dddfb5f | 593 | int ret; |
4cb28ced TG |
594 | |
595 | if (!cpu_online(cpu)) | |
596 | return 0; | |
597 | ||
5f4b55e1 PZ |
598 | cpuhp_lock_acquire(false); |
599 | cpuhp_lock_release(false); | |
600 | ||
601 | cpuhp_lock_acquire(true); | |
602 | cpuhp_lock_release(true); | |
49dfe2a6 | 603 | |
6a4e2451 TG |
604 | /* |
605 | * If we are up and running, use the hotplug thread. For early calls | |
606 | * we invoke the thread function directly. | |
607 | */ | |
608 | if (!st->thread) | |
96abb968 | 609 | return cpuhp_invoke_callback(cpu, state, bringup, node, NULL); |
6a4e2451 | 610 | |
4dddfb5f PZ |
611 | st->rollback = false; |
612 | st->last = NULL; | |
613 | ||
614 | st->node = node; | |
615 | st->bringup = bringup; | |
4cb28ced | 616 | st->cb_state = state; |
a724632c | 617 | st->single = true; |
a724632c | 618 | |
4dddfb5f | 619 | __cpuhp_kick_ap(st); |
4cb28ced | 620 | |
4cb28ced | 621 | /* |
4dddfb5f | 622 | * If we failed and did a partial, do a rollback. |
4cb28ced | 623 | */ |
4dddfb5f PZ |
624 | if ((ret = st->result) && st->last) { |
625 | st->rollback = true; | |
626 | st->bringup = !bringup; | |
627 | ||
628 | __cpuhp_kick_ap(st); | |
629 | } | |
630 | ||
1f7c70d6 TG |
631 | /* |
632 | * Clean up the leftovers so the next hotplug operation wont use stale | |
633 | * data. | |
634 | */ | |
635 | st->node = st->last = NULL; | |
4dddfb5f | 636 | return ret; |
1cf4f629 TG |
637 | } |
638 | ||
639 | static int cpuhp_kick_ap_work(unsigned int cpu) | |
640 | { | |
641 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
4dddfb5f PZ |
642 | enum cpuhp_state prev_state = st->state; |
643 | int ret; | |
1cf4f629 | 644 | |
5f4b55e1 PZ |
645 | cpuhp_lock_acquire(false); |
646 | cpuhp_lock_release(false); | |
647 | ||
648 | cpuhp_lock_acquire(true); | |
649 | cpuhp_lock_release(true); | |
4dddfb5f PZ |
650 | |
651 | trace_cpuhp_enter(cpu, st->target, prev_state, cpuhp_kick_ap_work); | |
652 | ret = cpuhp_kick_ap(st, st->target); | |
653 | trace_cpuhp_exit(cpu, st->state, prev_state, ret); | |
654 | ||
655 | return ret; | |
4cb28ced TG |
656 | } |
657 | ||
658 | static struct smp_hotplug_thread cpuhp_threads = { | |
659 | .store = &cpuhp_state.thread, | |
660 | .create = &cpuhp_create, | |
661 | .thread_should_run = cpuhp_should_run, | |
662 | .thread_fn = cpuhp_thread_fun, | |
663 | .thread_comm = "cpuhp/%u", | |
664 | .selfparking = true, | |
665 | }; | |
666 | ||
667 | void __init cpuhp_threads_init(void) | |
668 | { | |
669 | BUG_ON(smpboot_register_percpu_thread(&cpuhp_threads)); | |
670 | kthread_unpark(this_cpu_read(cpuhp_state.thread)); | |
671 | } | |
672 | ||
777c6e0d | 673 | #ifdef CONFIG_HOTPLUG_CPU |
e4cc2f87 AV |
674 | /** |
675 | * clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU | |
676 | * @cpu: a CPU id | |
677 | * | |
678 | * This function walks all processes, finds a valid mm struct for each one and | |
679 | * then clears a corresponding bit in mm's cpumask. While this all sounds | |
680 | * trivial, there are various non-obvious corner cases, which this function | |
681 | * tries to solve in a safe manner. | |
682 | * | |
683 | * Also note that the function uses a somewhat relaxed locking scheme, so it may | |
684 | * be called only for an already offlined CPU. | |
685 | */ | |
cb79295e AV |
686 | void clear_tasks_mm_cpumask(int cpu) |
687 | { | |
688 | struct task_struct *p; | |
689 | ||
690 | /* | |
691 | * This function is called after the cpu is taken down and marked | |
692 | * offline, so its not like new tasks will ever get this cpu set in | |
693 | * their mm mask. -- Peter Zijlstra | |
694 | * Thus, we may use rcu_read_lock() here, instead of grabbing | |
695 | * full-fledged tasklist_lock. | |
696 | */ | |
e4cc2f87 | 697 | WARN_ON(cpu_online(cpu)); |
cb79295e AV |
698 | rcu_read_lock(); |
699 | for_each_process(p) { | |
700 | struct task_struct *t; | |
701 | ||
e4cc2f87 AV |
702 | /* |
703 | * Main thread might exit, but other threads may still have | |
704 | * a valid mm. Find one. | |
705 | */ | |
cb79295e AV |
706 | t = find_lock_task_mm(p); |
707 | if (!t) | |
708 | continue; | |
709 | cpumask_clear_cpu(cpu, mm_cpumask(t->mm)); | |
710 | task_unlock(t); | |
711 | } | |
712 | rcu_read_unlock(); | |
713 | } | |
714 | ||
1da177e4 | 715 | /* Take this CPU down. */ |
71cf5aee | 716 | static int take_cpu_down(void *_param) |
1da177e4 | 717 | { |
4baa0afc TG |
718 | struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); |
719 | enum cpuhp_state target = max((int)st->target, CPUHP_AP_OFFLINE); | |
090e77c3 | 720 | int err, cpu = smp_processor_id(); |
724a8688 | 721 | int ret; |
1da177e4 | 722 | |
1da177e4 LT |
723 | /* Ensure this CPU doesn't handle any more interrupts. */ |
724 | err = __cpu_disable(); | |
725 | if (err < 0) | |
f3705136 | 726 | return err; |
1da177e4 | 727 | |
a724632c TG |
728 | /* |
729 | * We get here while we are in CPUHP_TEARDOWN_CPU state and we must not | |
730 | * do this step again. | |
731 | */ | |
732 | WARN_ON(st->state != CPUHP_TEARDOWN_CPU); | |
733 | st->state--; | |
4baa0afc | 734 | /* Invoke the former CPU_DYING callbacks */ |
724a8688 PZ |
735 | for (; st->state > target; st->state--) { |
736 | ret = cpuhp_invoke_callback(cpu, st->state, false, NULL, NULL); | |
737 | /* | |
738 | * DYING must not fail! | |
739 | */ | |
740 | WARN_ON_ONCE(ret); | |
741 | } | |
4baa0afc | 742 | |
52c063d1 TG |
743 | /* Give up timekeeping duties */ |
744 | tick_handover_do_timer(); | |
14e568e7 | 745 | /* Park the stopper thread */ |
090e77c3 | 746 | stop_machine_park(cpu); |
f3705136 | 747 | return 0; |
1da177e4 LT |
748 | } |
749 | ||
98458172 | 750 | static int takedown_cpu(unsigned int cpu) |
1da177e4 | 751 | { |
e69aab13 | 752 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); |
98458172 | 753 | int err; |
1da177e4 | 754 | |
2a58c527 | 755 | /* Park the smpboot threads */ |
1cf4f629 TG |
756 | kthread_park(per_cpu_ptr(&cpuhp_state, cpu)->thread); |
757 | ||
6acce3ef | 758 | /* |
a8994181 TG |
759 | * Prevent irq alloc/free while the dying cpu reorganizes the |
760 | * interrupt affinities. | |
6acce3ef | 761 | */ |
a8994181 | 762 | irq_lock_sparse(); |
6acce3ef | 763 | |
a8994181 TG |
764 | /* |
765 | * So now all preempt/rcu users must observe !cpu_active(). | |
766 | */ | |
210e2133 | 767 | err = stop_machine_cpuslocked(take_cpu_down, NULL, cpumask_of(cpu)); |
04321587 | 768 | if (err) { |
3b9d6da6 | 769 | /* CPU refused to die */ |
a8994181 | 770 | irq_unlock_sparse(); |
3b9d6da6 SAS |
771 | /* Unpark the hotplug thread so we can rollback there */ |
772 | kthread_unpark(per_cpu_ptr(&cpuhp_state, cpu)->thread); | |
98458172 | 773 | return err; |
8fa1d7d3 | 774 | } |
04321587 | 775 | BUG_ON(cpu_online(cpu)); |
1da177e4 | 776 | |
48c5ccae | 777 | /* |
5b1ead68 BJ |
778 | * The teardown callback for CPUHP_AP_SCHED_STARTING will have removed |
779 | * all runnable tasks from the CPU, there's only the idle task left now | |
48c5ccae | 780 | * that the migration thread is done doing the stop_machine thing. |
51a96c77 PZ |
781 | * |
782 | * Wait for the stop thread to go away. | |
48c5ccae | 783 | */ |
5ebe7742 | 784 | wait_for_ap_thread(st, false); |
e69aab13 | 785 | BUG_ON(st->state != CPUHP_AP_IDLE_DEAD); |
1da177e4 | 786 | |
a8994181 TG |
787 | /* Interrupts are moved away from the dying cpu, reenable alloc/free */ |
788 | irq_unlock_sparse(); | |
789 | ||
345527b1 | 790 | hotplug_cpu__broadcast_tick_pull(cpu); |
1da177e4 LT |
791 | /* This actually kills the CPU. */ |
792 | __cpu_die(cpu); | |
793 | ||
a49b116d | 794 | tick_cleanup_dead_cpu(cpu); |
a58163d8 | 795 | rcutree_migrate_callbacks(cpu); |
98458172 TG |
796 | return 0; |
797 | } | |
1da177e4 | 798 | |
71f87b2f TG |
799 | static void cpuhp_complete_idle_dead(void *arg) |
800 | { | |
801 | struct cpuhp_cpu_state *st = arg; | |
802 | ||
5ebe7742 | 803 | complete_ap_thread(st, false); |
71f87b2f TG |
804 | } |
805 | ||
e69aab13 TG |
806 | void cpuhp_report_idle_dead(void) |
807 | { | |
808 | struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); | |
809 | ||
810 | BUG_ON(st->state != CPUHP_AP_OFFLINE); | |
27d50c7e | 811 | rcu_report_dead(smp_processor_id()); |
71f87b2f TG |
812 | st->state = CPUHP_AP_IDLE_DEAD; |
813 | /* | |
814 | * We cannot call complete after rcu_report_dead() so we delegate it | |
815 | * to an online cpu. | |
816 | */ | |
817 | smp_call_function_single(cpumask_first(cpu_online_mask), | |
818 | cpuhp_complete_idle_dead, st, 0); | |
e69aab13 TG |
819 | } |
820 | ||
4dddfb5f PZ |
821 | static void undo_cpu_down(unsigned int cpu, struct cpuhp_cpu_state *st) |
822 | { | |
823 | for (st->state++; st->state < st->target; st->state++) { | |
824 | struct cpuhp_step *step = cpuhp_get_step(st->state); | |
cff7d378 | 825 | |
4dddfb5f PZ |
826 | if (!step->skip_onerr) |
827 | cpuhp_invoke_callback(cpu, st->state, true, NULL, NULL); | |
828 | } | |
829 | } | |
830 | ||
831 | static int cpuhp_down_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st, | |
832 | enum cpuhp_state target) | |
833 | { | |
834 | enum cpuhp_state prev_state = st->state; | |
835 | int ret = 0; | |
836 | ||
837 | for (; st->state > target; st->state--) { | |
838 | ret = cpuhp_invoke_callback(cpu, st->state, false, NULL, NULL); | |
839 | if (ret) { | |
840 | st->target = prev_state; | |
841 | undo_cpu_down(cpu, st); | |
842 | break; | |
843 | } | |
844 | } | |
845 | return ret; | |
846 | } | |
cff7d378 | 847 | |
98458172 | 848 | /* Requires cpu_add_remove_lock to be held */ |
af1f4045 TG |
849 | static int __ref _cpu_down(unsigned int cpu, int tasks_frozen, |
850 | enum cpuhp_state target) | |
98458172 | 851 | { |
cff7d378 TG |
852 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); |
853 | int prev_state, ret = 0; | |
98458172 TG |
854 | |
855 | if (num_online_cpus() == 1) | |
856 | return -EBUSY; | |
857 | ||
757c989b | 858 | if (!cpu_present(cpu)) |
98458172 TG |
859 | return -EINVAL; |
860 | ||
8f553c49 | 861 | cpus_write_lock(); |
98458172 TG |
862 | |
863 | cpuhp_tasks_frozen = tasks_frozen; | |
864 | ||
4dddfb5f | 865 | prev_state = cpuhp_set_state(st, target); |
1cf4f629 TG |
866 | /* |
867 | * If the current CPU state is in the range of the AP hotplug thread, | |
868 | * then we need to kick the thread. | |
869 | */ | |
8df3e07e | 870 | if (st->state > CPUHP_TEARDOWN_CPU) { |
4dddfb5f | 871 | st->target = max((int)target, CPUHP_TEARDOWN_CPU); |
1cf4f629 TG |
872 | ret = cpuhp_kick_ap_work(cpu); |
873 | /* | |
874 | * The AP side has done the error rollback already. Just | |
875 | * return the error code.. | |
876 | */ | |
877 | if (ret) | |
878 | goto out; | |
879 | ||
880 | /* | |
881 | * We might have stopped still in the range of the AP hotplug | |
882 | * thread. Nothing to do anymore. | |
883 | */ | |
8df3e07e | 884 | if (st->state > CPUHP_TEARDOWN_CPU) |
1cf4f629 | 885 | goto out; |
4dddfb5f PZ |
886 | |
887 | st->target = target; | |
1cf4f629 TG |
888 | } |
889 | /* | |
8df3e07e | 890 | * The AP brought itself down to CPUHP_TEARDOWN_CPU. So we need |
1cf4f629 TG |
891 | * to do the further cleanups. |
892 | */ | |
a724632c | 893 | ret = cpuhp_down_callbacks(cpu, st, target); |
3b9d6da6 | 894 | if (ret && st->state > CPUHP_TEARDOWN_CPU && st->state < prev_state) { |
4dddfb5f PZ |
895 | cpuhp_reset_state(st, prev_state); |
896 | __cpuhp_kick_ap(st); | |
3b9d6da6 | 897 | } |
98458172 | 898 | |
1cf4f629 | 899 | out: |
8f553c49 | 900 | cpus_write_unlock(); |
941154bd TG |
901 | /* |
902 | * Do post unplug cleanup. This is still protected against | |
903 | * concurrent CPU hotplug via cpu_add_remove_lock. | |
904 | */ | |
905 | lockup_detector_cleanup(); | |
cff7d378 | 906 | return ret; |
e3920fb4 RW |
907 | } |
908 | ||
cc1fe215 TG |
909 | static int cpu_down_maps_locked(unsigned int cpu, enum cpuhp_state target) |
910 | { | |
911 | if (cpu_hotplug_disabled) | |
912 | return -EBUSY; | |
913 | return _cpu_down(cpu, 0, target); | |
914 | } | |
915 | ||
af1f4045 | 916 | static int do_cpu_down(unsigned int cpu, enum cpuhp_state target) |
e3920fb4 | 917 | { |
9ea09af3 | 918 | int err; |
e3920fb4 | 919 | |
d221938c | 920 | cpu_maps_update_begin(); |
cc1fe215 | 921 | err = cpu_down_maps_locked(cpu, target); |
d221938c | 922 | cpu_maps_update_done(); |
1da177e4 LT |
923 | return err; |
924 | } | |
4dddfb5f | 925 | |
af1f4045 TG |
926 | int cpu_down(unsigned int cpu) |
927 | { | |
928 | return do_cpu_down(cpu, CPUHP_OFFLINE); | |
929 | } | |
b62b8ef9 | 930 | EXPORT_SYMBOL(cpu_down); |
4dddfb5f PZ |
931 | |
932 | #else | |
933 | #define takedown_cpu NULL | |
1da177e4 LT |
934 | #endif /*CONFIG_HOTPLUG_CPU*/ |
935 | ||
4baa0afc | 936 | /** |
ee1e714b | 937 | * notify_cpu_starting(cpu) - Invoke the callbacks on the starting CPU |
4baa0afc TG |
938 | * @cpu: cpu that just started |
939 | * | |
4baa0afc TG |
940 | * It must be called by the arch code on the new cpu, before the new cpu |
941 | * enables interrupts and before the "boot" cpu returns from __cpu_up(). | |
942 | */ | |
943 | void notify_cpu_starting(unsigned int cpu) | |
944 | { | |
945 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
946 | enum cpuhp_state target = min((int)st->target, CPUHP_AP_ONLINE); | |
724a8688 | 947 | int ret; |
4baa0afc | 948 | |
0c6d4576 | 949 | rcu_cpu_starting(cpu); /* Enables RCU usage on this CPU. */ |
4baa0afc | 950 | while (st->state < target) { |
4baa0afc | 951 | st->state++; |
724a8688 PZ |
952 | ret = cpuhp_invoke_callback(cpu, st->state, true, NULL, NULL); |
953 | /* | |
954 | * STARTING must not fail! | |
955 | */ | |
956 | WARN_ON_ONCE(ret); | |
4baa0afc TG |
957 | } |
958 | } | |
959 | ||
949338e3 | 960 | /* |
9cd4f1a4 TG |
961 | * Called from the idle task. Wake up the controlling task which brings the |
962 | * stopper and the hotplug thread of the upcoming CPU up and then delegates | |
963 | * the rest of the online bringup to the hotplug thread. | |
949338e3 | 964 | */ |
8df3e07e | 965 | void cpuhp_online_idle(enum cpuhp_state state) |
949338e3 | 966 | { |
8df3e07e | 967 | struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); |
8df3e07e TG |
968 | |
969 | /* Happens for the boot cpu */ | |
970 | if (state != CPUHP_AP_ONLINE_IDLE) | |
971 | return; | |
972 | ||
973 | st->state = CPUHP_AP_ONLINE_IDLE; | |
5ebe7742 | 974 | complete_ap_thread(st, true); |
949338e3 TG |
975 | } |
976 | ||
e3920fb4 | 977 | /* Requires cpu_add_remove_lock to be held */ |
af1f4045 | 978 | static int _cpu_up(unsigned int cpu, int tasks_frozen, enum cpuhp_state target) |
1da177e4 | 979 | { |
cff7d378 | 980 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); |
3bb5d2ee | 981 | struct task_struct *idle; |
2e1a3483 | 982 | int ret = 0; |
1da177e4 | 983 | |
8f553c49 | 984 | cpus_write_lock(); |
38498a67 | 985 | |
757c989b | 986 | if (!cpu_present(cpu)) { |
5e5041f3 YI |
987 | ret = -EINVAL; |
988 | goto out; | |
989 | } | |
990 | ||
757c989b TG |
991 | /* |
992 | * The caller of do_cpu_up might have raced with another | |
993 | * caller. Ignore it for now. | |
994 | */ | |
995 | if (st->state >= target) | |
38498a67 | 996 | goto out; |
757c989b TG |
997 | |
998 | if (st->state == CPUHP_OFFLINE) { | |
999 | /* Let it fail before we try to bring the cpu up */ | |
1000 | idle = idle_thread_get(cpu); | |
1001 | if (IS_ERR(idle)) { | |
1002 | ret = PTR_ERR(idle); | |
1003 | goto out; | |
1004 | } | |
3bb5d2ee | 1005 | } |
38498a67 | 1006 | |
ba997462 TG |
1007 | cpuhp_tasks_frozen = tasks_frozen; |
1008 | ||
4dddfb5f | 1009 | cpuhp_set_state(st, target); |
1cf4f629 TG |
1010 | /* |
1011 | * If the current CPU state is in the range of the AP hotplug thread, | |
1012 | * then we need to kick the thread once more. | |
1013 | */ | |
8df3e07e | 1014 | if (st->state > CPUHP_BRINGUP_CPU) { |
1cf4f629 TG |
1015 | ret = cpuhp_kick_ap_work(cpu); |
1016 | /* | |
1017 | * The AP side has done the error rollback already. Just | |
1018 | * return the error code.. | |
1019 | */ | |
1020 | if (ret) | |
1021 | goto out; | |
1022 | } | |
1023 | ||
1024 | /* | |
1025 | * Try to reach the target state. We max out on the BP at | |
8df3e07e | 1026 | * CPUHP_BRINGUP_CPU. After that the AP hotplug thread is |
1cf4f629 TG |
1027 | * responsible for bringing it up to the target state. |
1028 | */ | |
8df3e07e | 1029 | target = min((int)target, CPUHP_BRINGUP_CPU); |
a724632c | 1030 | ret = cpuhp_up_callbacks(cpu, st, target); |
38498a67 | 1031 | out: |
8f553c49 | 1032 | cpus_write_unlock(); |
e3920fb4 RW |
1033 | return ret; |
1034 | } | |
1035 | ||
af1f4045 | 1036 | static int do_cpu_up(unsigned int cpu, enum cpuhp_state target) |
e3920fb4 RW |
1037 | { |
1038 | int err = 0; | |
cf23422b | 1039 | |
e0b582ec | 1040 | if (!cpu_possible(cpu)) { |
84117da5 FF |
1041 | pr_err("can't online cpu %d because it is not configured as may-hotadd at boot time\n", |
1042 | cpu); | |
87d5e023 | 1043 | #if defined(CONFIG_IA64) |
84117da5 | 1044 | pr_err("please check additional_cpus= boot parameter\n"); |
73e753a5 KH |
1045 | #endif |
1046 | return -EINVAL; | |
1047 | } | |
e3920fb4 | 1048 | |
01b0f197 TK |
1049 | err = try_online_node(cpu_to_node(cpu)); |
1050 | if (err) | |
1051 | return err; | |
cf23422b | 1052 | |
d221938c | 1053 | cpu_maps_update_begin(); |
e761b772 MK |
1054 | |
1055 | if (cpu_hotplug_disabled) { | |
e3920fb4 | 1056 | err = -EBUSY; |
e761b772 MK |
1057 | goto out; |
1058 | } | |
1059 | ||
af1f4045 | 1060 | err = _cpu_up(cpu, 0, target); |
e761b772 | 1061 | out: |
d221938c | 1062 | cpu_maps_update_done(); |
e3920fb4 RW |
1063 | return err; |
1064 | } | |
af1f4045 TG |
1065 | |
1066 | int cpu_up(unsigned int cpu) | |
1067 | { | |
1068 | return do_cpu_up(cpu, CPUHP_ONLINE); | |
1069 | } | |
a513f6ba | 1070 | EXPORT_SYMBOL_GPL(cpu_up); |
e3920fb4 | 1071 | |
f3de4be9 | 1072 | #ifdef CONFIG_PM_SLEEP_SMP |
e0b582ec | 1073 | static cpumask_var_t frozen_cpus; |
e3920fb4 | 1074 | |
d391e552 | 1075 | int freeze_secondary_cpus(int primary) |
e3920fb4 | 1076 | { |
d391e552 | 1077 | int cpu, error = 0; |
e3920fb4 | 1078 | |
d221938c | 1079 | cpu_maps_update_begin(); |
d391e552 JM |
1080 | if (!cpu_online(primary)) |
1081 | primary = cpumask_first(cpu_online_mask); | |
9ee349ad XF |
1082 | /* |
1083 | * We take down all of the non-boot CPUs in one shot to avoid races | |
e3920fb4 RW |
1084 | * with the userspace trying to use the CPU hotplug at the same time |
1085 | */ | |
e0b582ec | 1086 | cpumask_clear(frozen_cpus); |
6ad4c188 | 1087 | |
84117da5 | 1088 | pr_info("Disabling non-boot CPUs ...\n"); |
e3920fb4 | 1089 | for_each_online_cpu(cpu) { |
d391e552 | 1090 | if (cpu == primary) |
e3920fb4 | 1091 | continue; |
bb3632c6 | 1092 | trace_suspend_resume(TPS("CPU_OFF"), cpu, true); |
af1f4045 | 1093 | error = _cpu_down(cpu, 1, CPUHP_OFFLINE); |
bb3632c6 | 1094 | trace_suspend_resume(TPS("CPU_OFF"), cpu, false); |
feae3203 | 1095 | if (!error) |
e0b582ec | 1096 | cpumask_set_cpu(cpu, frozen_cpus); |
feae3203 | 1097 | else { |
84117da5 | 1098 | pr_err("Error taking CPU%d down: %d\n", cpu, error); |
e3920fb4 RW |
1099 | break; |
1100 | } | |
1101 | } | |
86886e55 | 1102 | |
89af7ba5 | 1103 | if (!error) |
e3920fb4 | 1104 | BUG_ON(num_online_cpus() > 1); |
89af7ba5 | 1105 | else |
84117da5 | 1106 | pr_err("Non-boot CPUs are not disabled\n"); |
89af7ba5 VK |
1107 | |
1108 | /* | |
1109 | * Make sure the CPUs won't be enabled by someone else. We need to do | |
1110 | * this even in case of failure as all disable_nonboot_cpus() users are | |
1111 | * supposed to do enable_nonboot_cpus() on the failure path. | |
1112 | */ | |
1113 | cpu_hotplug_disabled++; | |
1114 | ||
d221938c | 1115 | cpu_maps_update_done(); |
e3920fb4 RW |
1116 | return error; |
1117 | } | |
1118 | ||
d0af9eed SS |
1119 | void __weak arch_enable_nonboot_cpus_begin(void) |
1120 | { | |
1121 | } | |
1122 | ||
1123 | void __weak arch_enable_nonboot_cpus_end(void) | |
1124 | { | |
1125 | } | |
1126 | ||
71cf5aee | 1127 | void enable_nonboot_cpus(void) |
e3920fb4 RW |
1128 | { |
1129 | int cpu, error; | |
1130 | ||
1131 | /* Allow everyone to use the CPU hotplug again */ | |
d221938c | 1132 | cpu_maps_update_begin(); |
01b41159 | 1133 | __cpu_hotplug_enable(); |
e0b582ec | 1134 | if (cpumask_empty(frozen_cpus)) |
1d64b9cb | 1135 | goto out; |
e3920fb4 | 1136 | |
84117da5 | 1137 | pr_info("Enabling non-boot CPUs ...\n"); |
d0af9eed SS |
1138 | |
1139 | arch_enable_nonboot_cpus_begin(); | |
1140 | ||
e0b582ec | 1141 | for_each_cpu(cpu, frozen_cpus) { |
bb3632c6 | 1142 | trace_suspend_resume(TPS("CPU_ON"), cpu, true); |
af1f4045 | 1143 | error = _cpu_up(cpu, 1, CPUHP_ONLINE); |
bb3632c6 | 1144 | trace_suspend_resume(TPS("CPU_ON"), cpu, false); |
e3920fb4 | 1145 | if (!error) { |
84117da5 | 1146 | pr_info("CPU%d is up\n", cpu); |
e3920fb4 RW |
1147 | continue; |
1148 | } | |
84117da5 | 1149 | pr_warn("Error taking CPU%d up: %d\n", cpu, error); |
e3920fb4 | 1150 | } |
d0af9eed SS |
1151 | |
1152 | arch_enable_nonboot_cpus_end(); | |
1153 | ||
e0b582ec | 1154 | cpumask_clear(frozen_cpus); |
1d64b9cb | 1155 | out: |
d221938c | 1156 | cpu_maps_update_done(); |
1da177e4 | 1157 | } |
e0b582ec | 1158 | |
d7268a31 | 1159 | static int __init alloc_frozen_cpus(void) |
e0b582ec RR |
1160 | { |
1161 | if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO)) | |
1162 | return -ENOMEM; | |
1163 | return 0; | |
1164 | } | |
1165 | core_initcall(alloc_frozen_cpus); | |
79cfbdfa | 1166 | |
79cfbdfa SB |
1167 | /* |
1168 | * When callbacks for CPU hotplug notifications are being executed, we must | |
1169 | * ensure that the state of the system with respect to the tasks being frozen | |
1170 | * or not, as reported by the notification, remains unchanged *throughout the | |
1171 | * duration* of the execution of the callbacks. | |
1172 | * Hence we need to prevent the freezer from racing with regular CPU hotplug. | |
1173 | * | |
1174 | * This synchronization is implemented by mutually excluding regular CPU | |
1175 | * hotplug and Suspend/Hibernate call paths by hooking onto the Suspend/ | |
1176 | * Hibernate notifications. | |
1177 | */ | |
1178 | static int | |
1179 | cpu_hotplug_pm_callback(struct notifier_block *nb, | |
1180 | unsigned long action, void *ptr) | |
1181 | { | |
1182 | switch (action) { | |
1183 | ||
1184 | case PM_SUSPEND_PREPARE: | |
1185 | case PM_HIBERNATION_PREPARE: | |
16e53dbf | 1186 | cpu_hotplug_disable(); |
79cfbdfa SB |
1187 | break; |
1188 | ||
1189 | case PM_POST_SUSPEND: | |
1190 | case PM_POST_HIBERNATION: | |
16e53dbf | 1191 | cpu_hotplug_enable(); |
79cfbdfa SB |
1192 | break; |
1193 | ||
1194 | default: | |
1195 | return NOTIFY_DONE; | |
1196 | } | |
1197 | ||
1198 | return NOTIFY_OK; | |
1199 | } | |
1200 | ||
1201 | ||
d7268a31 | 1202 | static int __init cpu_hotplug_pm_sync_init(void) |
79cfbdfa | 1203 | { |
6e32d479 FY |
1204 | /* |
1205 | * cpu_hotplug_pm_callback has higher priority than x86 | |
1206 | * bsp_pm_callback which depends on cpu_hotplug_pm_callback | |
1207 | * to disable cpu hotplug to avoid cpu hotplug race. | |
1208 | */ | |
79cfbdfa SB |
1209 | pm_notifier(cpu_hotplug_pm_callback, 0); |
1210 | return 0; | |
1211 | } | |
1212 | core_initcall(cpu_hotplug_pm_sync_init); | |
1213 | ||
f3de4be9 | 1214 | #endif /* CONFIG_PM_SLEEP_SMP */ |
68f4f1ec | 1215 | |
8ce371f9 PZ |
1216 | int __boot_cpu_id; |
1217 | ||
68f4f1ec | 1218 | #endif /* CONFIG_SMP */ |
b8d317d1 | 1219 | |
cff7d378 | 1220 | /* Boot processor state steps */ |
17a2f1ce | 1221 | static struct cpuhp_step cpuhp_hp_states[] = { |
cff7d378 TG |
1222 | [CPUHP_OFFLINE] = { |
1223 | .name = "offline", | |
3c1627e9 TG |
1224 | .startup.single = NULL, |
1225 | .teardown.single = NULL, | |
cff7d378 TG |
1226 | }, |
1227 | #ifdef CONFIG_SMP | |
1228 | [CPUHP_CREATE_THREADS]= { | |
677f6646 | 1229 | .name = "threads:prepare", |
3c1627e9 TG |
1230 | .startup.single = smpboot_create_threads, |
1231 | .teardown.single = NULL, | |
757c989b | 1232 | .cant_stop = true, |
cff7d378 | 1233 | }, |
00e16c3d | 1234 | [CPUHP_PERF_PREPARE] = { |
3c1627e9 TG |
1235 | .name = "perf:prepare", |
1236 | .startup.single = perf_event_init_cpu, | |
1237 | .teardown.single = perf_event_exit_cpu, | |
00e16c3d | 1238 | }, |
7ee681b2 | 1239 | [CPUHP_WORKQUEUE_PREP] = { |
3c1627e9 TG |
1240 | .name = "workqueue:prepare", |
1241 | .startup.single = workqueue_prepare_cpu, | |
1242 | .teardown.single = NULL, | |
7ee681b2 | 1243 | }, |
27590dc1 | 1244 | [CPUHP_HRTIMERS_PREPARE] = { |
3c1627e9 TG |
1245 | .name = "hrtimers:prepare", |
1246 | .startup.single = hrtimers_prepare_cpu, | |
1247 | .teardown.single = hrtimers_dead_cpu, | |
27590dc1 | 1248 | }, |
31487f83 | 1249 | [CPUHP_SMPCFD_PREPARE] = { |
677f6646 | 1250 | .name = "smpcfd:prepare", |
3c1627e9 TG |
1251 | .startup.single = smpcfd_prepare_cpu, |
1252 | .teardown.single = smpcfd_dead_cpu, | |
31487f83 | 1253 | }, |
e6d4989a RW |
1254 | [CPUHP_RELAY_PREPARE] = { |
1255 | .name = "relay:prepare", | |
1256 | .startup.single = relay_prepare_cpu, | |
1257 | .teardown.single = NULL, | |
1258 | }, | |
6731d4f1 SAS |
1259 | [CPUHP_SLAB_PREPARE] = { |
1260 | .name = "slab:prepare", | |
1261 | .startup.single = slab_prepare_cpu, | |
1262 | .teardown.single = slab_dead_cpu, | |
31487f83 | 1263 | }, |
4df83742 | 1264 | [CPUHP_RCUTREE_PREP] = { |
677f6646 | 1265 | .name = "RCU/tree:prepare", |
3c1627e9 TG |
1266 | .startup.single = rcutree_prepare_cpu, |
1267 | .teardown.single = rcutree_dead_cpu, | |
4df83742 | 1268 | }, |
4fae16df RC |
1269 | /* |
1270 | * On the tear-down path, timers_dead_cpu() must be invoked | |
1271 | * before blk_mq_queue_reinit_notify() from notify_dead(), | |
1272 | * otherwise a RCU stall occurs. | |
1273 | */ | |
26456f87 | 1274 | [CPUHP_TIMERS_PREPARE] = { |
3c1627e9 | 1275 | .name = "timers:dead", |
26456f87 | 1276 | .startup.single = timers_prepare_cpu, |
3c1627e9 | 1277 | .teardown.single = timers_dead_cpu, |
4fae16df | 1278 | }, |
d10ef6f9 | 1279 | /* Kicks the plugged cpu into life */ |
cff7d378 TG |
1280 | [CPUHP_BRINGUP_CPU] = { |
1281 | .name = "cpu:bringup", | |
3c1627e9 TG |
1282 | .startup.single = bringup_cpu, |
1283 | .teardown.single = NULL, | |
757c989b | 1284 | .cant_stop = true, |
4baa0afc | 1285 | }, |
d10ef6f9 TG |
1286 | /* Final state before CPU kills itself */ |
1287 | [CPUHP_AP_IDLE_DEAD] = { | |
1288 | .name = "idle:dead", | |
1289 | }, | |
1290 | /* | |
1291 | * Last state before CPU enters the idle loop to die. Transient state | |
1292 | * for synchronization. | |
1293 | */ | |
1294 | [CPUHP_AP_OFFLINE] = { | |
1295 | .name = "ap:offline", | |
1296 | .cant_stop = true, | |
1297 | }, | |
9cf7243d TG |
1298 | /* First state is scheduler control. Interrupts are disabled */ |
1299 | [CPUHP_AP_SCHED_STARTING] = { | |
1300 | .name = "sched:starting", | |
3c1627e9 TG |
1301 | .startup.single = sched_cpu_starting, |
1302 | .teardown.single = sched_cpu_dying, | |
9cf7243d | 1303 | }, |
4df83742 | 1304 | [CPUHP_AP_RCUTREE_DYING] = { |
677f6646 | 1305 | .name = "RCU/tree:dying", |
3c1627e9 TG |
1306 | .startup.single = NULL, |
1307 | .teardown.single = rcutree_dying_cpu, | |
4baa0afc | 1308 | }, |
46febd37 LJ |
1309 | [CPUHP_AP_SMPCFD_DYING] = { |
1310 | .name = "smpcfd:dying", | |
1311 | .startup.single = NULL, | |
1312 | .teardown.single = smpcfd_dying_cpu, | |
1313 | }, | |
d10ef6f9 TG |
1314 | /* Entry state on starting. Interrupts enabled from here on. Transient |
1315 | * state for synchronsization */ | |
1316 | [CPUHP_AP_ONLINE] = { | |
1317 | .name = "ap:online", | |
1318 | }, | |
17a2f1ce LJ |
1319 | /* |
1320 | * Handled on controll processor until the plugged processor manages | |
1321 | * this itself. | |
1322 | */ | |
1323 | [CPUHP_TEARDOWN_CPU] = { | |
1324 | .name = "cpu:teardown", | |
1325 | .startup.single = NULL, | |
1326 | .teardown.single = takedown_cpu, | |
1327 | .cant_stop = true, | |
1328 | }, | |
d10ef6f9 | 1329 | /* Handle smpboot threads park/unpark */ |
1cf4f629 | 1330 | [CPUHP_AP_SMPBOOT_THREADS] = { |
677f6646 | 1331 | .name = "smpboot/threads:online", |
3c1627e9 | 1332 | .startup.single = smpboot_unpark_threads, |
c4de6569 | 1333 | .teardown.single = smpboot_park_threads, |
1cf4f629 | 1334 | }, |
c5cb83bb TG |
1335 | [CPUHP_AP_IRQ_AFFINITY_ONLINE] = { |
1336 | .name = "irq/affinity:online", | |
1337 | .startup.single = irq_affinity_online_cpu, | |
1338 | .teardown.single = NULL, | |
1339 | }, | |
00e16c3d | 1340 | [CPUHP_AP_PERF_ONLINE] = { |
3c1627e9 TG |
1341 | .name = "perf:online", |
1342 | .startup.single = perf_event_init_cpu, | |
1343 | .teardown.single = perf_event_exit_cpu, | |
00e16c3d | 1344 | }, |
7ee681b2 | 1345 | [CPUHP_AP_WORKQUEUE_ONLINE] = { |
3c1627e9 TG |
1346 | .name = "workqueue:online", |
1347 | .startup.single = workqueue_online_cpu, | |
1348 | .teardown.single = workqueue_offline_cpu, | |
7ee681b2 | 1349 | }, |
4df83742 | 1350 | [CPUHP_AP_RCUTREE_ONLINE] = { |
677f6646 | 1351 | .name = "RCU/tree:online", |
3c1627e9 TG |
1352 | .startup.single = rcutree_online_cpu, |
1353 | .teardown.single = rcutree_offline_cpu, | |
4df83742 | 1354 | }, |
4baa0afc | 1355 | #endif |
d10ef6f9 TG |
1356 | /* |
1357 | * The dynamically registered state space is here | |
1358 | */ | |
1359 | ||
aaddd7d1 TG |
1360 | #ifdef CONFIG_SMP |
1361 | /* Last state is scheduler control setting the cpu active */ | |
1362 | [CPUHP_AP_ACTIVE] = { | |
1363 | .name = "sched:active", | |
3c1627e9 TG |
1364 | .startup.single = sched_cpu_activate, |
1365 | .teardown.single = sched_cpu_deactivate, | |
aaddd7d1 TG |
1366 | }, |
1367 | #endif | |
1368 | ||
d10ef6f9 | 1369 | /* CPU is fully up and running. */ |
4baa0afc TG |
1370 | [CPUHP_ONLINE] = { |
1371 | .name = "online", | |
3c1627e9 TG |
1372 | .startup.single = NULL, |
1373 | .teardown.single = NULL, | |
4baa0afc TG |
1374 | }, |
1375 | }; | |
1376 | ||
5b7aa87e TG |
1377 | /* Sanity check for callbacks */ |
1378 | static int cpuhp_cb_check(enum cpuhp_state state) | |
1379 | { | |
1380 | if (state <= CPUHP_OFFLINE || state >= CPUHP_ONLINE) | |
1381 | return -EINVAL; | |
1382 | return 0; | |
1383 | } | |
1384 | ||
dc280d93 TG |
1385 | /* |
1386 | * Returns a free for dynamic slot assignment of the Online state. The states | |
1387 | * are protected by the cpuhp_slot_states mutex and an empty slot is identified | |
1388 | * by having no name assigned. | |
1389 | */ | |
1390 | static int cpuhp_reserve_state(enum cpuhp_state state) | |
1391 | { | |
4205e478 TG |
1392 | enum cpuhp_state i, end; |
1393 | struct cpuhp_step *step; | |
dc280d93 | 1394 | |
4205e478 TG |
1395 | switch (state) { |
1396 | case CPUHP_AP_ONLINE_DYN: | |
17a2f1ce | 1397 | step = cpuhp_hp_states + CPUHP_AP_ONLINE_DYN; |
4205e478 TG |
1398 | end = CPUHP_AP_ONLINE_DYN_END; |
1399 | break; | |
1400 | case CPUHP_BP_PREPARE_DYN: | |
17a2f1ce | 1401 | step = cpuhp_hp_states + CPUHP_BP_PREPARE_DYN; |
4205e478 TG |
1402 | end = CPUHP_BP_PREPARE_DYN_END; |
1403 | break; | |
1404 | default: | |
1405 | return -EINVAL; | |
1406 | } | |
1407 | ||
1408 | for (i = state; i <= end; i++, step++) { | |
1409 | if (!step->name) | |
dc280d93 TG |
1410 | return i; |
1411 | } | |
1412 | WARN(1, "No more dynamic states available for CPU hotplug\n"); | |
1413 | return -ENOSPC; | |
1414 | } | |
1415 | ||
1416 | static int cpuhp_store_callbacks(enum cpuhp_state state, const char *name, | |
1417 | int (*startup)(unsigned int cpu), | |
1418 | int (*teardown)(unsigned int cpu), | |
1419 | bool multi_instance) | |
5b7aa87e TG |
1420 | { |
1421 | /* (Un)Install the callbacks for further cpu hotplug operations */ | |
1422 | struct cpuhp_step *sp; | |
dc280d93 | 1423 | int ret = 0; |
5b7aa87e | 1424 | |
0c96b273 EB |
1425 | /* |
1426 | * If name is NULL, then the state gets removed. | |
1427 | * | |
1428 | * CPUHP_AP_ONLINE_DYN and CPUHP_BP_PREPARE_DYN are handed out on | |
1429 | * the first allocation from these dynamic ranges, so the removal | |
1430 | * would trigger a new allocation and clear the wrong (already | |
1431 | * empty) state, leaving the callbacks of the to be cleared state | |
1432 | * dangling, which causes wreckage on the next hotplug operation. | |
1433 | */ | |
1434 | if (name && (state == CPUHP_AP_ONLINE_DYN || | |
1435 | state == CPUHP_BP_PREPARE_DYN)) { | |
dc280d93 TG |
1436 | ret = cpuhp_reserve_state(state); |
1437 | if (ret < 0) | |
dc434e05 | 1438 | return ret; |
dc280d93 TG |
1439 | state = ret; |
1440 | } | |
5b7aa87e | 1441 | sp = cpuhp_get_step(state); |
dc434e05 SAS |
1442 | if (name && sp->name) |
1443 | return -EBUSY; | |
1444 | ||
3c1627e9 TG |
1445 | sp->startup.single = startup; |
1446 | sp->teardown.single = teardown; | |
5b7aa87e | 1447 | sp->name = name; |
cf392d10 TG |
1448 | sp->multi_instance = multi_instance; |
1449 | INIT_HLIST_HEAD(&sp->list); | |
dc280d93 | 1450 | return ret; |
5b7aa87e TG |
1451 | } |
1452 | ||
1453 | static void *cpuhp_get_teardown_cb(enum cpuhp_state state) | |
1454 | { | |
3c1627e9 | 1455 | return cpuhp_get_step(state)->teardown.single; |
5b7aa87e TG |
1456 | } |
1457 | ||
5b7aa87e TG |
1458 | /* |
1459 | * Call the startup/teardown function for a step either on the AP or | |
1460 | * on the current CPU. | |
1461 | */ | |
cf392d10 TG |
1462 | static int cpuhp_issue_call(int cpu, enum cpuhp_state state, bool bringup, |
1463 | struct hlist_node *node) | |
5b7aa87e | 1464 | { |
a724632c | 1465 | struct cpuhp_step *sp = cpuhp_get_step(state); |
5b7aa87e TG |
1466 | int ret; |
1467 | ||
4dddfb5f PZ |
1468 | /* |
1469 | * If there's nothing to do, we done. | |
1470 | * Relies on the union for multi_instance. | |
1471 | */ | |
3c1627e9 TG |
1472 | if ((bringup && !sp->startup.single) || |
1473 | (!bringup && !sp->teardown.single)) | |
5b7aa87e | 1474 | return 0; |
5b7aa87e TG |
1475 | /* |
1476 | * The non AP bound callbacks can fail on bringup. On teardown | |
1477 | * e.g. module removal we crash for now. | |
1478 | */ | |
1cf4f629 TG |
1479 | #ifdef CONFIG_SMP |
1480 | if (cpuhp_is_ap_state(state)) | |
cf392d10 | 1481 | ret = cpuhp_invoke_ap_callback(cpu, state, bringup, node); |
1cf4f629 | 1482 | else |
96abb968 | 1483 | ret = cpuhp_invoke_callback(cpu, state, bringup, node, NULL); |
1cf4f629 | 1484 | #else |
96abb968 | 1485 | ret = cpuhp_invoke_callback(cpu, state, bringup, node, NULL); |
1cf4f629 | 1486 | #endif |
5b7aa87e TG |
1487 | BUG_ON(ret && !bringup); |
1488 | return ret; | |
1489 | } | |
1490 | ||
1491 | /* | |
1492 | * Called from __cpuhp_setup_state on a recoverable failure. | |
1493 | * | |
1494 | * Note: The teardown callbacks for rollback are not allowed to fail! | |
1495 | */ | |
1496 | static void cpuhp_rollback_install(int failedcpu, enum cpuhp_state state, | |
cf392d10 | 1497 | struct hlist_node *node) |
5b7aa87e TG |
1498 | { |
1499 | int cpu; | |
1500 | ||
5b7aa87e TG |
1501 | /* Roll back the already executed steps on the other cpus */ |
1502 | for_each_present_cpu(cpu) { | |
1503 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
1504 | int cpustate = st->state; | |
1505 | ||
1506 | if (cpu >= failedcpu) | |
1507 | break; | |
1508 | ||
1509 | /* Did we invoke the startup call on that cpu ? */ | |
1510 | if (cpustate >= state) | |
cf392d10 | 1511 | cpuhp_issue_call(cpu, state, false, node); |
5b7aa87e TG |
1512 | } |
1513 | } | |
1514 | ||
9805c673 TG |
1515 | int __cpuhp_state_add_instance_cpuslocked(enum cpuhp_state state, |
1516 | struct hlist_node *node, | |
1517 | bool invoke) | |
cf392d10 TG |
1518 | { |
1519 | struct cpuhp_step *sp; | |
1520 | int cpu; | |
1521 | int ret; | |
1522 | ||
9805c673 TG |
1523 | lockdep_assert_cpus_held(); |
1524 | ||
cf392d10 TG |
1525 | sp = cpuhp_get_step(state); |
1526 | if (sp->multi_instance == false) | |
1527 | return -EINVAL; | |
1528 | ||
dc434e05 | 1529 | mutex_lock(&cpuhp_state_mutex); |
cf392d10 | 1530 | |
3c1627e9 | 1531 | if (!invoke || !sp->startup.multi) |
cf392d10 TG |
1532 | goto add_node; |
1533 | ||
1534 | /* | |
1535 | * Try to call the startup callback for each present cpu | |
1536 | * depending on the hotplug state of the cpu. | |
1537 | */ | |
1538 | for_each_present_cpu(cpu) { | |
1539 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
1540 | int cpustate = st->state; | |
1541 | ||
1542 | if (cpustate < state) | |
1543 | continue; | |
1544 | ||
1545 | ret = cpuhp_issue_call(cpu, state, true, node); | |
1546 | if (ret) { | |
3c1627e9 | 1547 | if (sp->teardown.multi) |
cf392d10 | 1548 | cpuhp_rollback_install(cpu, state, node); |
dc434e05 | 1549 | goto unlock; |
cf392d10 TG |
1550 | } |
1551 | } | |
1552 | add_node: | |
1553 | ret = 0; | |
cf392d10 | 1554 | hlist_add_head(node, &sp->list); |
dc434e05 | 1555 | unlock: |
cf392d10 | 1556 | mutex_unlock(&cpuhp_state_mutex); |
9805c673 TG |
1557 | return ret; |
1558 | } | |
1559 | ||
1560 | int __cpuhp_state_add_instance(enum cpuhp_state state, struct hlist_node *node, | |
1561 | bool invoke) | |
1562 | { | |
1563 | int ret; | |
1564 | ||
1565 | cpus_read_lock(); | |
1566 | ret = __cpuhp_state_add_instance_cpuslocked(state, node, invoke); | |
8f553c49 | 1567 | cpus_read_unlock(); |
cf392d10 TG |
1568 | return ret; |
1569 | } | |
1570 | EXPORT_SYMBOL_GPL(__cpuhp_state_add_instance); | |
1571 | ||
5b7aa87e | 1572 | /** |
71def423 | 1573 | * __cpuhp_setup_state_cpuslocked - Setup the callbacks for an hotplug machine state |
dc280d93 TG |
1574 | * @state: The state to setup |
1575 | * @invoke: If true, the startup function is invoked for cpus where | |
1576 | * cpu state >= @state | |
1577 | * @startup: startup callback function | |
1578 | * @teardown: teardown callback function | |
1579 | * @multi_instance: State is set up for multiple instances which get | |
1580 | * added afterwards. | |
5b7aa87e | 1581 | * |
71def423 | 1582 | * The caller needs to hold cpus read locked while calling this function. |
512f0980 BO |
1583 | * Returns: |
1584 | * On success: | |
1585 | * Positive state number if @state is CPUHP_AP_ONLINE_DYN | |
1586 | * 0 for all other states | |
1587 | * On failure: proper (negative) error code | |
5b7aa87e | 1588 | */ |
71def423 SAS |
1589 | int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, |
1590 | const char *name, bool invoke, | |
1591 | int (*startup)(unsigned int cpu), | |
1592 | int (*teardown)(unsigned int cpu), | |
1593 | bool multi_instance) | |
5b7aa87e TG |
1594 | { |
1595 | int cpu, ret = 0; | |
b9d9d691 | 1596 | bool dynstate; |
5b7aa87e | 1597 | |
71def423 SAS |
1598 | lockdep_assert_cpus_held(); |
1599 | ||
5b7aa87e TG |
1600 | if (cpuhp_cb_check(state) || !name) |
1601 | return -EINVAL; | |
1602 | ||
dc434e05 | 1603 | mutex_lock(&cpuhp_state_mutex); |
5b7aa87e | 1604 | |
dc280d93 TG |
1605 | ret = cpuhp_store_callbacks(state, name, startup, teardown, |
1606 | multi_instance); | |
5b7aa87e | 1607 | |
b9d9d691 TG |
1608 | dynstate = state == CPUHP_AP_ONLINE_DYN; |
1609 | if (ret > 0 && dynstate) { | |
1610 | state = ret; | |
1611 | ret = 0; | |
1612 | } | |
1613 | ||
dc280d93 | 1614 | if (ret || !invoke || !startup) |
5b7aa87e TG |
1615 | goto out; |
1616 | ||
1617 | /* | |
1618 | * Try to call the startup callback for each present cpu | |
1619 | * depending on the hotplug state of the cpu. | |
1620 | */ | |
1621 | for_each_present_cpu(cpu) { | |
1622 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
1623 | int cpustate = st->state; | |
1624 | ||
1625 | if (cpustate < state) | |
1626 | continue; | |
1627 | ||
cf392d10 | 1628 | ret = cpuhp_issue_call(cpu, state, true, NULL); |
5b7aa87e | 1629 | if (ret) { |
a724632c | 1630 | if (teardown) |
cf392d10 TG |
1631 | cpuhp_rollback_install(cpu, state, NULL); |
1632 | cpuhp_store_callbacks(state, NULL, NULL, NULL, false); | |
5b7aa87e TG |
1633 | goto out; |
1634 | } | |
1635 | } | |
1636 | out: | |
dc434e05 | 1637 | mutex_unlock(&cpuhp_state_mutex); |
dc280d93 TG |
1638 | /* |
1639 | * If the requested state is CPUHP_AP_ONLINE_DYN, return the | |
1640 | * dynamically allocated state in case of success. | |
1641 | */ | |
b9d9d691 | 1642 | if (!ret && dynstate) |
5b7aa87e TG |
1643 | return state; |
1644 | return ret; | |
1645 | } | |
71def423 SAS |
1646 | EXPORT_SYMBOL(__cpuhp_setup_state_cpuslocked); |
1647 | ||
1648 | int __cpuhp_setup_state(enum cpuhp_state state, | |
1649 | const char *name, bool invoke, | |
1650 | int (*startup)(unsigned int cpu), | |
1651 | int (*teardown)(unsigned int cpu), | |
1652 | bool multi_instance) | |
1653 | { | |
1654 | int ret; | |
1655 | ||
1656 | cpus_read_lock(); | |
1657 | ret = __cpuhp_setup_state_cpuslocked(state, name, invoke, startup, | |
1658 | teardown, multi_instance); | |
1659 | cpus_read_unlock(); | |
1660 | return ret; | |
1661 | } | |
5b7aa87e TG |
1662 | EXPORT_SYMBOL(__cpuhp_setup_state); |
1663 | ||
cf392d10 TG |
1664 | int __cpuhp_state_remove_instance(enum cpuhp_state state, |
1665 | struct hlist_node *node, bool invoke) | |
1666 | { | |
1667 | struct cpuhp_step *sp = cpuhp_get_step(state); | |
1668 | int cpu; | |
1669 | ||
1670 | BUG_ON(cpuhp_cb_check(state)); | |
1671 | ||
1672 | if (!sp->multi_instance) | |
1673 | return -EINVAL; | |
1674 | ||
8f553c49 | 1675 | cpus_read_lock(); |
dc434e05 SAS |
1676 | mutex_lock(&cpuhp_state_mutex); |
1677 | ||
cf392d10 TG |
1678 | if (!invoke || !cpuhp_get_teardown_cb(state)) |
1679 | goto remove; | |
1680 | /* | |
1681 | * Call the teardown callback for each present cpu depending | |
1682 | * on the hotplug state of the cpu. This function is not | |
1683 | * allowed to fail currently! | |
1684 | */ | |
1685 | for_each_present_cpu(cpu) { | |
1686 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
1687 | int cpustate = st->state; | |
1688 | ||
1689 | if (cpustate >= state) | |
1690 | cpuhp_issue_call(cpu, state, false, node); | |
1691 | } | |
1692 | ||
1693 | remove: | |
cf392d10 TG |
1694 | hlist_del(node); |
1695 | mutex_unlock(&cpuhp_state_mutex); | |
8f553c49 | 1696 | cpus_read_unlock(); |
cf392d10 TG |
1697 | |
1698 | return 0; | |
1699 | } | |
1700 | EXPORT_SYMBOL_GPL(__cpuhp_state_remove_instance); | |
dc434e05 | 1701 | |
5b7aa87e | 1702 | /** |
71def423 | 1703 | * __cpuhp_remove_state_cpuslocked - Remove the callbacks for an hotplug machine state |
5b7aa87e TG |
1704 | * @state: The state to remove |
1705 | * @invoke: If true, the teardown function is invoked for cpus where | |
1706 | * cpu state >= @state | |
1707 | * | |
71def423 | 1708 | * The caller needs to hold cpus read locked while calling this function. |
5b7aa87e TG |
1709 | * The teardown callback is currently not allowed to fail. Think |
1710 | * about module removal! | |
1711 | */ | |
71def423 | 1712 | void __cpuhp_remove_state_cpuslocked(enum cpuhp_state state, bool invoke) |
5b7aa87e | 1713 | { |
cf392d10 | 1714 | struct cpuhp_step *sp = cpuhp_get_step(state); |
5b7aa87e TG |
1715 | int cpu; |
1716 | ||
1717 | BUG_ON(cpuhp_cb_check(state)); | |
1718 | ||
71def423 | 1719 | lockdep_assert_cpus_held(); |
5b7aa87e | 1720 | |
dc434e05 | 1721 | mutex_lock(&cpuhp_state_mutex); |
cf392d10 TG |
1722 | if (sp->multi_instance) { |
1723 | WARN(!hlist_empty(&sp->list), | |
1724 | "Error: Removing state %d which has instances left.\n", | |
1725 | state); | |
1726 | goto remove; | |
1727 | } | |
1728 | ||
a724632c | 1729 | if (!invoke || !cpuhp_get_teardown_cb(state)) |
5b7aa87e TG |
1730 | goto remove; |
1731 | ||
1732 | /* | |
1733 | * Call the teardown callback for each present cpu depending | |
1734 | * on the hotplug state of the cpu. This function is not | |
1735 | * allowed to fail currently! | |
1736 | */ | |
1737 | for_each_present_cpu(cpu) { | |
1738 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); | |
1739 | int cpustate = st->state; | |
1740 | ||
1741 | if (cpustate >= state) | |
cf392d10 | 1742 | cpuhp_issue_call(cpu, state, false, NULL); |
5b7aa87e TG |
1743 | } |
1744 | remove: | |
cf392d10 | 1745 | cpuhp_store_callbacks(state, NULL, NULL, NULL, false); |
dc434e05 | 1746 | mutex_unlock(&cpuhp_state_mutex); |
71def423 SAS |
1747 | } |
1748 | EXPORT_SYMBOL(__cpuhp_remove_state_cpuslocked); | |
1749 | ||
1750 | void __cpuhp_remove_state(enum cpuhp_state state, bool invoke) | |
1751 | { | |
1752 | cpus_read_lock(); | |
1753 | __cpuhp_remove_state_cpuslocked(state, invoke); | |
8f553c49 | 1754 | cpus_read_unlock(); |
5b7aa87e TG |
1755 | } |
1756 | EXPORT_SYMBOL(__cpuhp_remove_state); | |
1757 | ||
98f8cdce TG |
1758 | #if defined(CONFIG_SYSFS) && defined(CONFIG_HOTPLUG_CPU) |
1759 | static ssize_t show_cpuhp_state(struct device *dev, | |
1760 | struct device_attribute *attr, char *buf) | |
1761 | { | |
1762 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id); | |
1763 | ||
1764 | return sprintf(buf, "%d\n", st->state); | |
1765 | } | |
1766 | static DEVICE_ATTR(state, 0444, show_cpuhp_state, NULL); | |
1767 | ||
757c989b TG |
1768 | static ssize_t write_cpuhp_target(struct device *dev, |
1769 | struct device_attribute *attr, | |
1770 | const char *buf, size_t count) | |
1771 | { | |
1772 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id); | |
1773 | struct cpuhp_step *sp; | |
1774 | int target, ret; | |
1775 | ||
1776 | ret = kstrtoint(buf, 10, &target); | |
1777 | if (ret) | |
1778 | return ret; | |
1779 | ||
1780 | #ifdef CONFIG_CPU_HOTPLUG_STATE_CONTROL | |
1781 | if (target < CPUHP_OFFLINE || target > CPUHP_ONLINE) | |
1782 | return -EINVAL; | |
1783 | #else | |
1784 | if (target != CPUHP_OFFLINE && target != CPUHP_ONLINE) | |
1785 | return -EINVAL; | |
1786 | #endif | |
1787 | ||
1788 | ret = lock_device_hotplug_sysfs(); | |
1789 | if (ret) | |
1790 | return ret; | |
1791 | ||
1792 | mutex_lock(&cpuhp_state_mutex); | |
1793 | sp = cpuhp_get_step(target); | |
1794 | ret = !sp->name || sp->cant_stop ? -EINVAL : 0; | |
1795 | mutex_unlock(&cpuhp_state_mutex); | |
1796 | if (ret) | |
40da1b11 | 1797 | goto out; |
757c989b TG |
1798 | |
1799 | if (st->state < target) | |
1800 | ret = do_cpu_up(dev->id, target); | |
1801 | else | |
1802 | ret = do_cpu_down(dev->id, target); | |
40da1b11 | 1803 | out: |
757c989b TG |
1804 | unlock_device_hotplug(); |
1805 | return ret ? ret : count; | |
1806 | } | |
1807 | ||
98f8cdce TG |
1808 | static ssize_t show_cpuhp_target(struct device *dev, |
1809 | struct device_attribute *attr, char *buf) | |
1810 | { | |
1811 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id); | |
1812 | ||
1813 | return sprintf(buf, "%d\n", st->target); | |
1814 | } | |
757c989b | 1815 | static DEVICE_ATTR(target, 0644, show_cpuhp_target, write_cpuhp_target); |
98f8cdce | 1816 | |
1db49484 PZ |
1817 | |
1818 | static ssize_t write_cpuhp_fail(struct device *dev, | |
1819 | struct device_attribute *attr, | |
1820 | const char *buf, size_t count) | |
1821 | { | |
1822 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id); | |
1823 | struct cpuhp_step *sp; | |
1824 | int fail, ret; | |
1825 | ||
1826 | ret = kstrtoint(buf, 10, &fail); | |
1827 | if (ret) | |
1828 | return ret; | |
1829 | ||
1830 | /* | |
1831 | * Cannot fail STARTING/DYING callbacks. | |
1832 | */ | |
1833 | if (cpuhp_is_atomic_state(fail)) | |
1834 | return -EINVAL; | |
1835 | ||
1836 | /* | |
1837 | * Cannot fail anything that doesn't have callbacks. | |
1838 | */ | |
1839 | mutex_lock(&cpuhp_state_mutex); | |
1840 | sp = cpuhp_get_step(fail); | |
1841 | if (!sp->startup.single && !sp->teardown.single) | |
1842 | ret = -EINVAL; | |
1843 | mutex_unlock(&cpuhp_state_mutex); | |
1844 | if (ret) | |
1845 | return ret; | |
1846 | ||
1847 | st->fail = fail; | |
1848 | ||
1849 | return count; | |
1850 | } | |
1851 | ||
1852 | static ssize_t show_cpuhp_fail(struct device *dev, | |
1853 | struct device_attribute *attr, char *buf) | |
1854 | { | |
1855 | struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id); | |
1856 | ||
1857 | return sprintf(buf, "%d\n", st->fail); | |
1858 | } | |
1859 | ||
1860 | static DEVICE_ATTR(fail, 0644, show_cpuhp_fail, write_cpuhp_fail); | |
1861 | ||
98f8cdce TG |
1862 | static struct attribute *cpuhp_cpu_attrs[] = { |
1863 | &dev_attr_state.attr, | |
1864 | &dev_attr_target.attr, | |
1db49484 | 1865 | &dev_attr_fail.attr, |
98f8cdce TG |
1866 | NULL |
1867 | }; | |
1868 | ||
993647a2 | 1869 | static const struct attribute_group cpuhp_cpu_attr_group = { |
98f8cdce TG |
1870 | .attrs = cpuhp_cpu_attrs, |
1871 | .name = "hotplug", | |
1872 | NULL | |
1873 | }; | |
1874 | ||
1875 | static ssize_t show_cpuhp_states(struct device *dev, | |
1876 | struct device_attribute *attr, char *buf) | |
1877 | { | |
1878 | ssize_t cur, res = 0; | |
1879 | int i; | |
1880 | ||
1881 | mutex_lock(&cpuhp_state_mutex); | |
757c989b | 1882 | for (i = CPUHP_OFFLINE; i <= CPUHP_ONLINE; i++) { |
98f8cdce TG |
1883 | struct cpuhp_step *sp = cpuhp_get_step(i); |
1884 | ||
1885 | if (sp->name) { | |
1886 | cur = sprintf(buf, "%3d: %s\n", i, sp->name); | |
1887 | buf += cur; | |
1888 | res += cur; | |
1889 | } | |
1890 | } | |
1891 | mutex_unlock(&cpuhp_state_mutex); | |
1892 | return res; | |
1893 | } | |
1894 | static DEVICE_ATTR(states, 0444, show_cpuhp_states, NULL); | |
1895 | ||
1896 | static struct attribute *cpuhp_cpu_root_attrs[] = { | |
1897 | &dev_attr_states.attr, | |
1898 | NULL | |
1899 | }; | |
1900 | ||
993647a2 | 1901 | static const struct attribute_group cpuhp_cpu_root_attr_group = { |
98f8cdce TG |
1902 | .attrs = cpuhp_cpu_root_attrs, |
1903 | .name = "hotplug", | |
1904 | NULL | |
1905 | }; | |
1906 | ||
1907 | static int __init cpuhp_sysfs_init(void) | |
1908 | { | |
1909 | int cpu, ret; | |
1910 | ||
1911 | ret = sysfs_create_group(&cpu_subsys.dev_root->kobj, | |
1912 | &cpuhp_cpu_root_attr_group); | |
1913 | if (ret) | |
1914 | return ret; | |
1915 | ||
1916 | for_each_possible_cpu(cpu) { | |
1917 | struct device *dev = get_cpu_device(cpu); | |
1918 | ||
1919 | if (!dev) | |
1920 | continue; | |
1921 | ret = sysfs_create_group(&dev->kobj, &cpuhp_cpu_attr_group); | |
1922 | if (ret) | |
1923 | return ret; | |
1924 | } | |
1925 | return 0; | |
1926 | } | |
1927 | device_initcall(cpuhp_sysfs_init); | |
1928 | #endif | |
1929 | ||
e56b3bc7 LT |
1930 | /* |
1931 | * cpu_bit_bitmap[] is a special, "compressed" data structure that | |
1932 | * represents all NR_CPUS bits binary values of 1<<nr. | |
1933 | * | |
e0b582ec | 1934 | * It is used by cpumask_of() to get a constant address to a CPU |
e56b3bc7 LT |
1935 | * mask value that has a single bit set only. |
1936 | */ | |
b8d317d1 | 1937 | |
e56b3bc7 | 1938 | /* cpu_bit_bitmap[0] is empty - so we can back into it */ |
4d51985e | 1939 | #define MASK_DECLARE_1(x) [x+1][0] = (1UL << (x)) |
e56b3bc7 LT |
1940 | #define MASK_DECLARE_2(x) MASK_DECLARE_1(x), MASK_DECLARE_1(x+1) |
1941 | #define MASK_DECLARE_4(x) MASK_DECLARE_2(x), MASK_DECLARE_2(x+2) | |
1942 | #define MASK_DECLARE_8(x) MASK_DECLARE_4(x), MASK_DECLARE_4(x+4) | |
b8d317d1 | 1943 | |
e56b3bc7 LT |
1944 | const unsigned long cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)] = { |
1945 | ||
1946 | MASK_DECLARE_8(0), MASK_DECLARE_8(8), | |
1947 | MASK_DECLARE_8(16), MASK_DECLARE_8(24), | |
1948 | #if BITS_PER_LONG > 32 | |
1949 | MASK_DECLARE_8(32), MASK_DECLARE_8(40), | |
1950 | MASK_DECLARE_8(48), MASK_DECLARE_8(56), | |
b8d317d1 MT |
1951 | #endif |
1952 | }; | |
e56b3bc7 | 1953 | EXPORT_SYMBOL_GPL(cpu_bit_bitmap); |
2d3854a3 RR |
1954 | |
1955 | const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL; | |
1956 | EXPORT_SYMBOL(cpu_all_bits); | |
b3199c02 RR |
1957 | |
1958 | #ifdef CONFIG_INIT_ALL_POSSIBLE | |
4b804c85 | 1959 | struct cpumask __cpu_possible_mask __read_mostly |
c4c54dd1 | 1960 | = {CPU_BITS_ALL}; |
b3199c02 | 1961 | #else |
4b804c85 | 1962 | struct cpumask __cpu_possible_mask __read_mostly; |
b3199c02 | 1963 | #endif |
4b804c85 | 1964 | EXPORT_SYMBOL(__cpu_possible_mask); |
b3199c02 | 1965 | |
4b804c85 RV |
1966 | struct cpumask __cpu_online_mask __read_mostly; |
1967 | EXPORT_SYMBOL(__cpu_online_mask); | |
b3199c02 | 1968 | |
4b804c85 RV |
1969 | struct cpumask __cpu_present_mask __read_mostly; |
1970 | EXPORT_SYMBOL(__cpu_present_mask); | |
b3199c02 | 1971 | |
4b804c85 RV |
1972 | struct cpumask __cpu_active_mask __read_mostly; |
1973 | EXPORT_SYMBOL(__cpu_active_mask); | |
3fa41520 | 1974 | |
3fa41520 RR |
1975 | void init_cpu_present(const struct cpumask *src) |
1976 | { | |
c4c54dd1 | 1977 | cpumask_copy(&__cpu_present_mask, src); |
3fa41520 RR |
1978 | } |
1979 | ||
1980 | void init_cpu_possible(const struct cpumask *src) | |
1981 | { | |
c4c54dd1 | 1982 | cpumask_copy(&__cpu_possible_mask, src); |
3fa41520 RR |
1983 | } |
1984 | ||
1985 | void init_cpu_online(const struct cpumask *src) | |
1986 | { | |
c4c54dd1 | 1987 | cpumask_copy(&__cpu_online_mask, src); |
3fa41520 | 1988 | } |
cff7d378 TG |
1989 | |
1990 | /* | |
1991 | * Activate the first processor. | |
1992 | */ | |
1993 | void __init boot_cpu_init(void) | |
1994 | { | |
1995 | int cpu = smp_processor_id(); | |
1996 | ||
1997 | /* Mark the boot cpu "present", "online" etc for SMP and UP case */ | |
1998 | set_cpu_online(cpu, true); | |
1999 | set_cpu_active(cpu, true); | |
2000 | set_cpu_present(cpu, true); | |
2001 | set_cpu_possible(cpu, true); | |
8ce371f9 PZ |
2002 | |
2003 | #ifdef CONFIG_SMP | |
2004 | __boot_cpu_id = cpu; | |
2005 | #endif | |
cff7d378 TG |
2006 | } |
2007 | ||
2008 | /* | |
2009 | * Must be called _AFTER_ setting up the per_cpu areas | |
2010 | */ | |
2011 | void __init boot_cpu_state_init(void) | |
2012 | { | |
2013 | per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE; | |
2014 | } |