Commit | Line | Data |
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16295bec SK |
1 | /* |
2 | * padata.c - generic interface to process data streams in parallel | |
3 | * | |
107f8bda SK |
4 | * See Documentation/padata.txt for an api documentation. |
5 | * | |
16295bec SK |
6 | * Copyright (C) 2008, 2009 secunet Security Networks AG |
7 | * Copyright (C) 2008, 2009 Steffen Klassert <steffen.klassert@secunet.com> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify it | |
10 | * under the terms and conditions of the GNU General Public License, | |
11 | * version 2, as published by the Free Software Foundation. | |
12 | * | |
13 | * This program is distributed in the hope it will be useful, but WITHOUT | |
14 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
16 | * more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License along with | |
19 | * this program; if not, write to the Free Software Foundation, Inc., | |
20 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
21 | */ | |
22 | ||
9984de1a | 23 | #include <linux/export.h> |
16295bec SK |
24 | #include <linux/cpumask.h> |
25 | #include <linux/err.h> | |
26 | #include <linux/cpu.h> | |
27 | #include <linux/padata.h> | |
28 | #include <linux/mutex.h> | |
29 | #include <linux/sched.h> | |
5a0e3ad6 | 30 | #include <linux/slab.h> |
5e017dc3 | 31 | #include <linux/sysfs.h> |
16295bec | 32 | #include <linux/rcupdate.h> |
30e92153 | 33 | #include <linux/module.h> |
16295bec | 34 | |
97e3d94a | 35 | #define MAX_OBJ_NUM 1000 |
16295bec SK |
36 | |
37 | static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index) | |
38 | { | |
39 | int cpu, target_cpu; | |
40 | ||
e15bacbe | 41 | target_cpu = cpumask_first(pd->cpumask.pcpu); |
16295bec | 42 | for (cpu = 0; cpu < cpu_index; cpu++) |
e15bacbe | 43 | target_cpu = cpumask_next(target_cpu, pd->cpumask.pcpu); |
16295bec SK |
44 | |
45 | return target_cpu; | |
46 | } | |
47 | ||
2dc9b5db | 48 | static int padata_cpu_hash(struct parallel_data *pd) |
16295bec | 49 | { |
0b6b098e | 50 | unsigned int seq_nr; |
16295bec | 51 | int cpu_index; |
16295bec SK |
52 | |
53 | /* | |
54 | * Hash the sequence numbers to the cpus by taking | |
55 | * seq_nr mod. number of cpus in use. | |
56 | */ | |
2dc9b5db | 57 | |
0b6b098e MK |
58 | seq_nr = atomic_inc_return(&pd->seq_nr); |
59 | cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu); | |
16295bec SK |
60 | |
61 | return padata_index_to_cpu(pd, cpu_index); | |
62 | } | |
63 | ||
e15bacbe | 64 | static void padata_parallel_worker(struct work_struct *parallel_work) |
16295bec | 65 | { |
e15bacbe | 66 | struct padata_parallel_queue *pqueue; |
16295bec SK |
67 | LIST_HEAD(local_list); |
68 | ||
69 | local_bh_disable(); | |
e15bacbe DK |
70 | pqueue = container_of(parallel_work, |
71 | struct padata_parallel_queue, work); | |
16295bec | 72 | |
e15bacbe DK |
73 | spin_lock(&pqueue->parallel.lock); |
74 | list_replace_init(&pqueue->parallel.list, &local_list); | |
75 | spin_unlock(&pqueue->parallel.lock); | |
16295bec SK |
76 | |
77 | while (!list_empty(&local_list)) { | |
78 | struct padata_priv *padata; | |
79 | ||
80 | padata = list_entry(local_list.next, | |
81 | struct padata_priv, list); | |
82 | ||
83 | list_del_init(&padata->list); | |
84 | ||
85 | padata->parallel(padata); | |
86 | } | |
87 | ||
88 | local_bh_enable(); | |
89 | } | |
90 | ||
0198ffd1 | 91 | /** |
16295bec SK |
92 | * padata_do_parallel - padata parallelization function |
93 | * | |
94 | * @pinst: padata instance | |
95 | * @padata: object to be parallelized | |
96 | * @cb_cpu: cpu the serialization callback function will run on, | |
e15bacbe | 97 | * must be in the serial cpumask of padata(i.e. cpumask.cbcpu). |
16295bec SK |
98 | * |
99 | * The parallelization callback function will run with BHs off. | |
100 | * Note: Every object which is parallelized by padata_do_parallel | |
101 | * must be seen by padata_do_serial. | |
102 | */ | |
103 | int padata_do_parallel(struct padata_instance *pinst, | |
104 | struct padata_priv *padata, int cb_cpu) | |
105 | { | |
106 | int target_cpu, err; | |
e15bacbe | 107 | struct padata_parallel_queue *queue; |
16295bec SK |
108 | struct parallel_data *pd; |
109 | ||
110 | rcu_read_lock_bh(); | |
111 | ||
c0e656b7 | 112 | pd = rcu_dereference_bh(pinst->pd); |
16295bec | 113 | |
83f619f3 | 114 | err = -EINVAL; |
7424713b | 115 | if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID) |
16295bec SK |
116 | goto out; |
117 | ||
e15bacbe | 118 | if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu)) |
16295bec SK |
119 | goto out; |
120 | ||
121 | err = -EBUSY; | |
122 | if ((pinst->flags & PADATA_RESET)) | |
123 | goto out; | |
124 | ||
125 | if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM) | |
126 | goto out; | |
127 | ||
83f619f3 | 128 | err = 0; |
16295bec SK |
129 | atomic_inc(&pd->refcnt); |
130 | padata->pd = pd; | |
131 | padata->cb_cpu = cb_cpu; | |
132 | ||
2dc9b5db | 133 | target_cpu = padata_cpu_hash(pd); |
e15bacbe | 134 | queue = per_cpu_ptr(pd->pqueue, target_cpu); |
16295bec SK |
135 | |
136 | spin_lock(&queue->parallel.lock); | |
137 | list_add_tail(&padata->list, &queue->parallel.list); | |
138 | spin_unlock(&queue->parallel.lock); | |
139 | ||
e15bacbe | 140 | queue_work_on(target_cpu, pinst->wq, &queue->work); |
16295bec SK |
141 | |
142 | out: | |
143 | rcu_read_unlock_bh(); | |
144 | ||
145 | return err; | |
146 | } | |
147 | EXPORT_SYMBOL(padata_do_parallel); | |
148 | ||
0198ffd1 SK |
149 | /* |
150 | * padata_get_next - Get the next object that needs serialization. | |
151 | * | |
152 | * Return values are: | |
153 | * | |
154 | * A pointer to the control struct of the next object that needs | |
155 | * serialization, if present in one of the percpu reorder queues. | |
156 | * | |
0198ffd1 SK |
157 | * -EINPROGRESS, if the next object that needs serialization will |
158 | * be parallel processed by another cpu and is not yet present in | |
159 | * the cpu's reorder queue. | |
160 | * | |
161 | * -ENODATA, if this cpu has to do the parallel processing for | |
162 | * the next object. | |
163 | */ | |
16295bec SK |
164 | static struct padata_priv *padata_get_next(struct parallel_data *pd) |
165 | { | |
5f1a8c1b | 166 | int cpu, num_cpus; |
2dc9b5db | 167 | unsigned int next_nr, next_index; |
f0fcf200 | 168 | struct padata_parallel_queue *next_queue; |
16295bec SK |
169 | struct padata_priv *padata; |
170 | struct padata_list *reorder; | |
171 | ||
e15bacbe | 172 | num_cpus = cpumask_weight(pd->cpumask.pcpu); |
16295bec | 173 | |
5f1a8c1b SK |
174 | /* |
175 | * Calculate the percpu reorder queue and the sequence | |
176 | * number of the next object. | |
177 | */ | |
178 | next_nr = pd->processed; | |
179 | next_index = next_nr % num_cpus; | |
180 | cpu = padata_index_to_cpu(pd, next_index); | |
e15bacbe | 181 | next_queue = per_cpu_ptr(pd->pqueue, cpu); |
5f1a8c1b | 182 | |
16295bec SK |
183 | reorder = &next_queue->reorder; |
184 | ||
de5540d0 | 185 | spin_lock(&reorder->lock); |
16295bec SK |
186 | if (!list_empty(&reorder->list)) { |
187 | padata = list_entry(reorder->list.next, | |
188 | struct padata_priv, list); | |
189 | ||
16295bec SK |
190 | list_del_init(&padata->list); |
191 | atomic_dec(&pd->reorder_objects); | |
16295bec | 192 | |
5f1a8c1b | 193 | pd->processed++; |
16295bec | 194 | |
de5540d0 | 195 | spin_unlock(&reorder->lock); |
16295bec SK |
196 | goto out; |
197 | } | |
de5540d0 | 198 | spin_unlock(&reorder->lock); |
16295bec | 199 | |
f0fcf200 | 200 | if (__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index) { |
16295bec SK |
201 | padata = ERR_PTR(-ENODATA); |
202 | goto out; | |
203 | } | |
204 | ||
205 | padata = ERR_PTR(-EINPROGRESS); | |
206 | out: | |
207 | return padata; | |
208 | } | |
209 | ||
210 | static void padata_reorder(struct parallel_data *pd) | |
211 | { | |
3047817b | 212 | int cb_cpu; |
16295bec | 213 | struct padata_priv *padata; |
e15bacbe | 214 | struct padata_serial_queue *squeue; |
16295bec SK |
215 | struct padata_instance *pinst = pd->pinst; |
216 | ||
0198ffd1 SK |
217 | /* |
218 | * We need to ensure that only one cpu can work on dequeueing of | |
219 | * the reorder queue the time. Calculating in which percpu reorder | |
220 | * queue the next object will arrive takes some time. A spinlock | |
221 | * would be highly contended. Also it is not clear in which order | |
222 | * the objects arrive to the reorder queues. So a cpu could wait to | |
223 | * get the lock just to notice that there is nothing to do at the | |
224 | * moment. Therefore we use a trylock and let the holder of the lock | |
225 | * care for all the objects enqueued during the holdtime of the lock. | |
226 | */ | |
16295bec | 227 | if (!spin_trylock_bh(&pd->lock)) |
d46a5ac7 | 228 | return; |
16295bec SK |
229 | |
230 | while (1) { | |
231 | padata = padata_get_next(pd); | |
232 | ||
0198ffd1 | 233 | /* |
69b34844 JD |
234 | * If the next object that needs serialization is parallel |
235 | * processed by another cpu and is still on it's way to the | |
236 | * cpu's reorder queue, nothing to do for now. | |
0198ffd1 | 237 | */ |
69b34844 | 238 | if (PTR_ERR(padata) == -EINPROGRESS) |
16295bec SK |
239 | break; |
240 | ||
0198ffd1 SK |
241 | /* |
242 | * This cpu has to do the parallel processing of the next | |
243 | * object. It's waiting in the cpu's parallelization queue, | |
25985edc | 244 | * so exit immediately. |
0198ffd1 | 245 | */ |
16295bec | 246 | if (PTR_ERR(padata) == -ENODATA) { |
d46a5ac7 | 247 | del_timer(&pd->timer); |
16295bec | 248 | spin_unlock_bh(&pd->lock); |
d46a5ac7 | 249 | return; |
16295bec SK |
250 | } |
251 | ||
3047817b SK |
252 | cb_cpu = padata->cb_cpu; |
253 | squeue = per_cpu_ptr(pd->squeue, cb_cpu); | |
16295bec | 254 | |
e15bacbe DK |
255 | spin_lock(&squeue->serial.lock); |
256 | list_add_tail(&padata->list, &squeue->serial.list); | |
257 | spin_unlock(&squeue->serial.lock); | |
16295bec | 258 | |
3047817b | 259 | queue_work_on(cb_cpu, pinst->wq, &squeue->work); |
16295bec SK |
260 | } |
261 | ||
262 | spin_unlock_bh(&pd->lock); | |
263 | ||
0198ffd1 SK |
264 | /* |
265 | * The next object that needs serialization might have arrived to | |
266 | * the reorder queues in the meantime, we will be called again | |
25985edc | 267 | * from the timer function if no one else cares for it. |
0198ffd1 | 268 | */ |
d46a5ac7 SK |
269 | if (atomic_read(&pd->reorder_objects) |
270 | && !(pinst->flags & PADATA_RESET)) | |
271 | mod_timer(&pd->timer, jiffies + HZ); | |
272 | else | |
273 | del_timer(&pd->timer); | |
16295bec | 274 | |
16295bec SK |
275 | return; |
276 | } | |
277 | ||
cf5868c8 MK |
278 | static void invoke_padata_reorder(struct work_struct *work) |
279 | { | |
280 | struct padata_parallel_queue *pqueue; | |
281 | struct parallel_data *pd; | |
282 | ||
283 | local_bh_disable(); | |
284 | pqueue = container_of(work, struct padata_parallel_queue, reorder_work); | |
285 | pd = pqueue->pd; | |
286 | padata_reorder(pd); | |
287 | local_bh_enable(); | |
288 | } | |
289 | ||
d46a5ac7 SK |
290 | static void padata_reorder_timer(unsigned long arg) |
291 | { | |
292 | struct parallel_data *pd = (struct parallel_data *)arg; | |
cf5868c8 MK |
293 | unsigned int weight; |
294 | int target_cpu, cpu; | |
d46a5ac7 | 295 | |
cf5868c8 MK |
296 | cpu = get_cpu(); |
297 | ||
298 | /* We don't lock pd here to not interfere with parallel processing | |
299 | * padata_reorder() calls on other CPUs. We just need any CPU out of | |
300 | * the cpumask.pcpu set. It would be nice if it's the right one but | |
301 | * it doesn't matter if we're off to the next one by using an outdated | |
302 | * pd->processed value. | |
303 | */ | |
304 | weight = cpumask_weight(pd->cpumask.pcpu); | |
305 | target_cpu = padata_index_to_cpu(pd, pd->processed % weight); | |
306 | ||
307 | /* ensure to call the reorder callback on the correct CPU */ | |
308 | if (cpu != target_cpu) { | |
309 | struct padata_parallel_queue *pqueue; | |
310 | struct padata_instance *pinst; | |
311 | ||
312 | /* The timer function is serialized wrt itself -- no locking | |
313 | * needed. | |
314 | */ | |
315 | pinst = pd->pinst; | |
316 | pqueue = per_cpu_ptr(pd->pqueue, target_cpu); | |
317 | queue_work_on(target_cpu, pinst->wq, &pqueue->reorder_work); | |
318 | } else { | |
319 | padata_reorder(pd); | |
320 | } | |
321 | ||
322 | put_cpu(); | |
d46a5ac7 SK |
323 | } |
324 | ||
e15bacbe | 325 | static void padata_serial_worker(struct work_struct *serial_work) |
16295bec | 326 | { |
e15bacbe | 327 | struct padata_serial_queue *squeue; |
16295bec SK |
328 | struct parallel_data *pd; |
329 | LIST_HEAD(local_list); | |
330 | ||
331 | local_bh_disable(); | |
e15bacbe DK |
332 | squeue = container_of(serial_work, struct padata_serial_queue, work); |
333 | pd = squeue->pd; | |
16295bec | 334 | |
e15bacbe DK |
335 | spin_lock(&squeue->serial.lock); |
336 | list_replace_init(&squeue->serial.list, &local_list); | |
337 | spin_unlock(&squeue->serial.lock); | |
16295bec SK |
338 | |
339 | while (!list_empty(&local_list)) { | |
340 | struct padata_priv *padata; | |
341 | ||
342 | padata = list_entry(local_list.next, | |
343 | struct padata_priv, list); | |
344 | ||
345 | list_del_init(&padata->list); | |
346 | ||
347 | padata->serial(padata); | |
348 | atomic_dec(&pd->refcnt); | |
349 | } | |
350 | local_bh_enable(); | |
351 | } | |
352 | ||
0198ffd1 | 353 | /** |
16295bec SK |
354 | * padata_do_serial - padata serialization function |
355 | * | |
356 | * @padata: object to be serialized. | |
357 | * | |
358 | * padata_do_serial must be called for every parallelized object. | |
359 | * The serialization callback function will run with BHs off. | |
360 | */ | |
361 | void padata_do_serial(struct padata_priv *padata) | |
362 | { | |
363 | int cpu; | |
e15bacbe | 364 | struct padata_parallel_queue *pqueue; |
16295bec SK |
365 | struct parallel_data *pd; |
366 | ||
367 | pd = padata->pd; | |
368 | ||
369 | cpu = get_cpu(); | |
e15bacbe | 370 | pqueue = per_cpu_ptr(pd->pqueue, cpu); |
16295bec | 371 | |
e15bacbe | 372 | spin_lock(&pqueue->reorder.lock); |
16295bec | 373 | atomic_inc(&pd->reorder_objects); |
e15bacbe DK |
374 | list_add_tail(&padata->list, &pqueue->reorder.list); |
375 | spin_unlock(&pqueue->reorder.lock); | |
16295bec SK |
376 | |
377 | put_cpu(); | |
378 | ||
379 | padata_reorder(pd); | |
380 | } | |
381 | EXPORT_SYMBOL(padata_do_serial); | |
382 | ||
e15bacbe DK |
383 | static int padata_setup_cpumasks(struct parallel_data *pd, |
384 | const struct cpumask *pcpumask, | |
385 | const struct cpumask *cbcpumask) | |
16295bec | 386 | { |
e15bacbe DK |
387 | if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL)) |
388 | return -ENOMEM; | |
16295bec | 389 | |
13614e0f | 390 | cpumask_and(pd->cpumask.pcpu, pcpumask, cpu_online_mask); |
e15bacbe | 391 | if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) { |
07a77929 | 392 | free_cpumask_var(pd->cpumask.pcpu); |
e15bacbe DK |
393 | return -ENOMEM; |
394 | } | |
16295bec | 395 | |
13614e0f | 396 | cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_online_mask); |
e15bacbe DK |
397 | return 0; |
398 | } | |
16295bec | 399 | |
e15bacbe DK |
400 | static void __padata_list_init(struct padata_list *pd_list) |
401 | { | |
402 | INIT_LIST_HEAD(&pd_list->list); | |
403 | spin_lock_init(&pd_list->lock); | |
404 | } | |
16295bec | 405 | |
e15bacbe DK |
406 | /* Initialize all percpu queues used by serial workers */ |
407 | static void padata_init_squeues(struct parallel_data *pd) | |
408 | { | |
409 | int cpu; | |
410 | struct padata_serial_queue *squeue; | |
7b389b2c | 411 | |
e15bacbe DK |
412 | for_each_cpu(cpu, pd->cpumask.cbcpu) { |
413 | squeue = per_cpu_ptr(pd->squeue, cpu); | |
414 | squeue->pd = pd; | |
415 | __padata_list_init(&squeue->serial); | |
416 | INIT_WORK(&squeue->work, padata_serial_worker); | |
417 | } | |
418 | } | |
16295bec | 419 | |
e15bacbe DK |
420 | /* Initialize all percpu queues used by parallel workers */ |
421 | static void padata_init_pqueues(struct parallel_data *pd) | |
422 | { | |
2dc9b5db | 423 | int cpu_index, cpu; |
e15bacbe | 424 | struct padata_parallel_queue *pqueue; |
16295bec | 425 | |
e15bacbe | 426 | cpu_index = 0; |
1bd845bc | 427 | for_each_possible_cpu(cpu) { |
e15bacbe | 428 | pqueue = per_cpu_ptr(pd->pqueue, cpu); |
1bd845bc MK |
429 | |
430 | if (!cpumask_test_cpu(cpu, pd->cpumask.pcpu)) { | |
431 | pqueue->cpu_index = -1; | |
432 | continue; | |
433 | } | |
434 | ||
e15bacbe DK |
435 | pqueue->pd = pd; |
436 | pqueue->cpu_index = cpu_index; | |
7b389b2c | 437 | cpu_index++; |
16295bec | 438 | |
e15bacbe DK |
439 | __padata_list_init(&pqueue->reorder); |
440 | __padata_list_init(&pqueue->parallel); | |
441 | INIT_WORK(&pqueue->work, padata_parallel_worker); | |
cf5868c8 | 442 | INIT_WORK(&pqueue->reorder_work, invoke_padata_reorder); |
e15bacbe | 443 | atomic_set(&pqueue->num_obj, 0); |
16295bec | 444 | } |
e15bacbe | 445 | } |
16295bec | 446 | |
e15bacbe DK |
447 | /* Allocate and initialize the internal cpumask dependend resources. */ |
448 | static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst, | |
449 | const struct cpumask *pcpumask, | |
450 | const struct cpumask *cbcpumask) | |
451 | { | |
452 | struct parallel_data *pd; | |
16295bec | 453 | |
e15bacbe DK |
454 | pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL); |
455 | if (!pd) | |
456 | goto err; | |
16295bec | 457 | |
e15bacbe DK |
458 | pd->pqueue = alloc_percpu(struct padata_parallel_queue); |
459 | if (!pd->pqueue) | |
460 | goto err_free_pd; | |
461 | ||
462 | pd->squeue = alloc_percpu(struct padata_serial_queue); | |
463 | if (!pd->squeue) | |
464 | goto err_free_pqueue; | |
465 | if (padata_setup_cpumasks(pd, pcpumask, cbcpumask) < 0) | |
466 | goto err_free_squeue; | |
16295bec | 467 | |
e15bacbe DK |
468 | padata_init_pqueues(pd); |
469 | padata_init_squeues(pd); | |
d46a5ac7 | 470 | setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd); |
0b6b098e | 471 | atomic_set(&pd->seq_nr, -1); |
16295bec SK |
472 | atomic_set(&pd->reorder_objects, 0); |
473 | atomic_set(&pd->refcnt, 0); | |
474 | pd->pinst = pinst; | |
475 | spin_lock_init(&pd->lock); | |
476 | ||
477 | return pd; | |
478 | ||
e15bacbe DK |
479 | err_free_squeue: |
480 | free_percpu(pd->squeue); | |
481 | err_free_pqueue: | |
482 | free_percpu(pd->pqueue); | |
16295bec SK |
483 | err_free_pd: |
484 | kfree(pd); | |
485 | err: | |
486 | return NULL; | |
487 | } | |
488 | ||
489 | static void padata_free_pd(struct parallel_data *pd) | |
490 | { | |
e15bacbe DK |
491 | free_cpumask_var(pd->cpumask.pcpu); |
492 | free_cpumask_var(pd->cpumask.cbcpu); | |
493 | free_percpu(pd->pqueue); | |
494 | free_percpu(pd->squeue); | |
16295bec SK |
495 | kfree(pd); |
496 | } | |
497 | ||
0198ffd1 | 498 | /* Flush all objects out of the padata queues. */ |
2b73b07a SK |
499 | static void padata_flush_queues(struct parallel_data *pd) |
500 | { | |
501 | int cpu; | |
e15bacbe DK |
502 | struct padata_parallel_queue *pqueue; |
503 | struct padata_serial_queue *squeue; | |
2b73b07a | 504 | |
e15bacbe DK |
505 | for_each_cpu(cpu, pd->cpumask.pcpu) { |
506 | pqueue = per_cpu_ptr(pd->pqueue, cpu); | |
507 | flush_work(&pqueue->work); | |
2b73b07a SK |
508 | } |
509 | ||
510 | del_timer_sync(&pd->timer); | |
511 | ||
512 | if (atomic_read(&pd->reorder_objects)) | |
513 | padata_reorder(pd); | |
514 | ||
e15bacbe DK |
515 | for_each_cpu(cpu, pd->cpumask.cbcpu) { |
516 | squeue = per_cpu_ptr(pd->squeue, cpu); | |
517 | flush_work(&squeue->work); | |
2b73b07a SK |
518 | } |
519 | ||
520 | BUG_ON(atomic_read(&pd->refcnt) != 0); | |
521 | } | |
522 | ||
4c879170 SK |
523 | static void __padata_start(struct padata_instance *pinst) |
524 | { | |
525 | pinst->flags |= PADATA_INIT; | |
526 | } | |
527 | ||
ee836555 SK |
528 | static void __padata_stop(struct padata_instance *pinst) |
529 | { | |
530 | if (!(pinst->flags & PADATA_INIT)) | |
531 | return; | |
532 | ||
533 | pinst->flags &= ~PADATA_INIT; | |
534 | ||
535 | synchronize_rcu(); | |
536 | ||
537 | get_online_cpus(); | |
538 | padata_flush_queues(pinst->pd); | |
539 | put_online_cpus(); | |
540 | } | |
541 | ||
25985edc | 542 | /* Replace the internal control structure with a new one. */ |
16295bec SK |
543 | static void padata_replace(struct padata_instance *pinst, |
544 | struct parallel_data *pd_new) | |
545 | { | |
546 | struct parallel_data *pd_old = pinst->pd; | |
e15bacbe | 547 | int notification_mask = 0; |
16295bec SK |
548 | |
549 | pinst->flags |= PADATA_RESET; | |
550 | ||
551 | rcu_assign_pointer(pinst->pd, pd_new); | |
552 | ||
553 | synchronize_rcu(); | |
554 | ||
e15bacbe DK |
555 | if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu)) |
556 | notification_mask |= PADATA_CPU_PARALLEL; | |
557 | if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu)) | |
558 | notification_mask |= PADATA_CPU_SERIAL; | |
559 | ||
2b73b07a | 560 | padata_flush_queues(pd_old); |
16295bec SK |
561 | padata_free_pd(pd_old); |
562 | ||
e15bacbe DK |
563 | if (notification_mask) |
564 | blocking_notifier_call_chain(&pinst->cpumask_change_notifier, | |
c635696c SK |
565 | notification_mask, |
566 | &pd_new->cpumask); | |
16295bec SK |
567 | |
568 | pinst->flags &= ~PADATA_RESET; | |
569 | } | |
570 | ||
0198ffd1 | 571 | /** |
e15bacbe DK |
572 | * padata_register_cpumask_notifier - Registers a notifier that will be called |
573 | * if either pcpu or cbcpu or both cpumasks change. | |
16295bec | 574 | * |
e15bacbe DK |
575 | * @pinst: A poineter to padata instance |
576 | * @nblock: A pointer to notifier block. | |
16295bec | 577 | */ |
e15bacbe DK |
578 | int padata_register_cpumask_notifier(struct padata_instance *pinst, |
579 | struct notifier_block *nblock) | |
16295bec | 580 | { |
e15bacbe DK |
581 | return blocking_notifier_chain_register(&pinst->cpumask_change_notifier, |
582 | nblock); | |
583 | } | |
584 | EXPORT_SYMBOL(padata_register_cpumask_notifier); | |
585 | ||
586 | /** | |
587 | * padata_unregister_cpumask_notifier - Unregisters cpumask notifier | |
588 | * registered earlier using padata_register_cpumask_notifier | |
589 | * | |
590 | * @pinst: A pointer to data instance. | |
591 | * @nlock: A pointer to notifier block. | |
592 | */ | |
593 | int padata_unregister_cpumask_notifier(struct padata_instance *pinst, | |
594 | struct notifier_block *nblock) | |
595 | { | |
596 | return blocking_notifier_chain_unregister( | |
597 | &pinst->cpumask_change_notifier, | |
598 | nblock); | |
599 | } | |
600 | EXPORT_SYMBOL(padata_unregister_cpumask_notifier); | |
601 | ||
602 | ||
33e54450 SK |
603 | /* If cpumask contains no active cpu, we mark the instance as invalid. */ |
604 | static bool padata_validate_cpumask(struct padata_instance *pinst, | |
605 | const struct cpumask *cpumask) | |
606 | { | |
13614e0f | 607 | if (!cpumask_intersects(cpumask, cpu_online_mask)) { |
33e54450 SK |
608 | pinst->flags |= PADATA_INVALID; |
609 | return false; | |
610 | } | |
611 | ||
612 | pinst->flags &= ~PADATA_INVALID; | |
613 | return true; | |
614 | } | |
615 | ||
65ff577e SK |
616 | static int __padata_set_cpumasks(struct padata_instance *pinst, |
617 | cpumask_var_t pcpumask, | |
618 | cpumask_var_t cbcpumask) | |
619 | { | |
620 | int valid; | |
16295bec | 621 | struct parallel_data *pd; |
65ff577e SK |
622 | |
623 | valid = padata_validate_cpumask(pinst, pcpumask); | |
624 | if (!valid) { | |
625 | __padata_stop(pinst); | |
626 | goto out_replace; | |
627 | } | |
628 | ||
629 | valid = padata_validate_cpumask(pinst, cbcpumask); | |
630 | if (!valid) | |
631 | __padata_stop(pinst); | |
632 | ||
633 | out_replace: | |
634 | pd = padata_alloc_pd(pinst, pcpumask, cbcpumask); | |
635 | if (!pd) | |
636 | return -ENOMEM; | |
637 | ||
638 | cpumask_copy(pinst->cpumask.pcpu, pcpumask); | |
639 | cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); | |
640 | ||
641 | padata_replace(pinst, pd); | |
642 | ||
643 | if (valid) | |
644 | __padata_start(pinst); | |
645 | ||
646 | return 0; | |
647 | } | |
648 | ||
e15bacbe DK |
649 | /** |
650 | * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value | |
651 | * equivalent to @cpumask. | |
16295bec SK |
652 | * |
653 | * @pinst: padata instance | |
e15bacbe DK |
654 | * @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding |
655 | * to parallel and serial cpumasks respectively. | |
16295bec SK |
656 | * @cpumask: the cpumask to use |
657 | */ | |
e15bacbe DK |
658 | int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type, |
659 | cpumask_var_t cpumask) | |
660 | { | |
661 | struct cpumask *serial_mask, *parallel_mask; | |
65ff577e SK |
662 | int err = -EINVAL; |
663 | ||
664 | mutex_lock(&pinst->lock); | |
6751fb3c SK |
665 | get_online_cpus(); |
666 | ||
e15bacbe DK |
667 | switch (cpumask_type) { |
668 | case PADATA_CPU_PARALLEL: | |
669 | serial_mask = pinst->cpumask.cbcpu; | |
670 | parallel_mask = cpumask; | |
671 | break; | |
672 | case PADATA_CPU_SERIAL: | |
673 | parallel_mask = pinst->cpumask.pcpu; | |
674 | serial_mask = cpumask; | |
675 | break; | |
676 | default: | |
65ff577e | 677 | goto out; |
16295bec SK |
678 | } |
679 | ||
65ff577e | 680 | err = __padata_set_cpumasks(pinst, parallel_mask, serial_mask); |
16295bec SK |
681 | |
682 | out: | |
6751fb3c | 683 | put_online_cpus(); |
16295bec SK |
684 | mutex_unlock(&pinst->lock); |
685 | ||
686 | return err; | |
687 | } | |
688 | EXPORT_SYMBOL(padata_set_cpumask); | |
689 | ||
19d795b6 AB |
690 | /** |
691 | * padata_start - start the parallel processing | |
692 | * | |
693 | * @pinst: padata instance to start | |
694 | */ | |
695 | int padata_start(struct padata_instance *pinst) | |
696 | { | |
697 | int err = 0; | |
698 | ||
699 | mutex_lock(&pinst->lock); | |
700 | ||
701 | if (pinst->flags & PADATA_INVALID) | |
702 | err = -EINVAL; | |
703 | ||
704 | __padata_start(pinst); | |
705 | ||
706 | mutex_unlock(&pinst->lock); | |
707 | ||
708 | return err; | |
709 | } | |
710 | EXPORT_SYMBOL(padata_start); | |
711 | ||
712 | /** | |
713 | * padata_stop - stop the parallel processing | |
714 | * | |
715 | * @pinst: padata instance to stop | |
716 | */ | |
717 | void padata_stop(struct padata_instance *pinst) | |
718 | { | |
719 | mutex_lock(&pinst->lock); | |
720 | __padata_stop(pinst); | |
721 | mutex_unlock(&pinst->lock); | |
722 | } | |
723 | EXPORT_SYMBOL(padata_stop); | |
724 | ||
725 | #ifdef CONFIG_HOTPLUG_CPU | |
726 | ||
16295bec SK |
727 | static int __padata_add_cpu(struct padata_instance *pinst, int cpu) |
728 | { | |
729 | struct parallel_data *pd; | |
730 | ||
13614e0f | 731 | if (cpumask_test_cpu(cpu, cpu_online_mask)) { |
e15bacbe DK |
732 | pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu, |
733 | pinst->cpumask.cbcpu); | |
16295bec SK |
734 | if (!pd) |
735 | return -ENOMEM; | |
736 | ||
737 | padata_replace(pinst, pd); | |
33e54450 | 738 | |
e15bacbe DK |
739 | if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) && |
740 | padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) | |
33e54450 | 741 | __padata_start(pinst); |
16295bec SK |
742 | } |
743 | ||
744 | return 0; | |
745 | } | |
746 | ||
16295bec SK |
747 | static int __padata_remove_cpu(struct padata_instance *pinst, int cpu) |
748 | { | |
33e54450 | 749 | struct parallel_data *pd = NULL; |
16295bec SK |
750 | |
751 | if (cpumask_test_cpu(cpu, cpu_online_mask)) { | |
33e54450 | 752 | |
e15bacbe | 753 | if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) || |
b89661df | 754 | !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) |
33e54450 | 755 | __padata_stop(pinst); |
33e54450 | 756 | |
e15bacbe DK |
757 | pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu, |
758 | pinst->cpumask.cbcpu); | |
16295bec SK |
759 | if (!pd) |
760 | return -ENOMEM; | |
761 | ||
762 | padata_replace(pinst, pd); | |
96120905 SK |
763 | |
764 | cpumask_clear_cpu(cpu, pd->cpumask.cbcpu); | |
765 | cpumask_clear_cpu(cpu, pd->cpumask.pcpu); | |
16295bec SK |
766 | } |
767 | ||
768 | return 0; | |
769 | } | |
770 | ||
e15bacbe | 771 | /** |
25985edc | 772 | * padata_remove_cpu - remove a cpu from the one or both(serial and parallel) |
e15bacbe | 773 | * padata cpumasks. |
16295bec SK |
774 | * |
775 | * @pinst: padata instance | |
776 | * @cpu: cpu to remove | |
e15bacbe DK |
777 | * @mask: bitmask specifying from which cpumask @cpu should be removed |
778 | * The @mask may be any combination of the following flags: | |
779 | * PADATA_CPU_SERIAL - serial cpumask | |
780 | * PADATA_CPU_PARALLEL - parallel cpumask | |
16295bec | 781 | */ |
e15bacbe | 782 | int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask) |
16295bec SK |
783 | { |
784 | int err; | |
785 | ||
e15bacbe DK |
786 | if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL))) |
787 | return -EINVAL; | |
788 | ||
16295bec SK |
789 | mutex_lock(&pinst->lock); |
790 | ||
6751fb3c | 791 | get_online_cpus(); |
e15bacbe DK |
792 | if (mask & PADATA_CPU_SERIAL) |
793 | cpumask_clear_cpu(cpu, pinst->cpumask.cbcpu); | |
794 | if (mask & PADATA_CPU_PARALLEL) | |
795 | cpumask_clear_cpu(cpu, pinst->cpumask.pcpu); | |
796 | ||
16295bec | 797 | err = __padata_remove_cpu(pinst, cpu); |
6751fb3c | 798 | put_online_cpus(); |
16295bec SK |
799 | |
800 | mutex_unlock(&pinst->lock); | |
801 | ||
802 | return err; | |
803 | } | |
804 | EXPORT_SYMBOL(padata_remove_cpu); | |
805 | ||
e15bacbe DK |
806 | static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu) |
807 | { | |
808 | return cpumask_test_cpu(cpu, pinst->cpumask.pcpu) || | |
809 | cpumask_test_cpu(cpu, pinst->cpumask.cbcpu); | |
810 | } | |
811 | ||
30e92153 | 812 | static int padata_cpu_online(unsigned int cpu, struct hlist_node *node) |
16295bec | 813 | { |
16295bec | 814 | struct padata_instance *pinst; |
30e92153 | 815 | int ret; |
16295bec | 816 | |
30e92153 SAS |
817 | pinst = hlist_entry_safe(node, struct padata_instance, node); |
818 | if (!pinst_has_cpu(pinst, cpu)) | |
819 | return 0; | |
16295bec | 820 | |
30e92153 SAS |
821 | mutex_lock(&pinst->lock); |
822 | ret = __padata_add_cpu(pinst, cpu); | |
823 | mutex_unlock(&pinst->lock); | |
824 | return ret; | |
825 | } | |
16295bec | 826 | |
30e92153 SAS |
827 | static int padata_cpu_prep_down(unsigned int cpu, struct hlist_node *node) |
828 | { | |
829 | struct padata_instance *pinst; | |
830 | int ret; | |
831 | ||
832 | pinst = hlist_entry_safe(node, struct padata_instance, node); | |
833 | if (!pinst_has_cpu(pinst, cpu)) | |
834 | return 0; | |
16295bec | 835 | |
30e92153 SAS |
836 | mutex_lock(&pinst->lock); |
837 | ret = __padata_remove_cpu(pinst, cpu); | |
838 | mutex_unlock(&pinst->lock); | |
839 | return ret; | |
16295bec | 840 | } |
30e92153 SAS |
841 | |
842 | static enum cpuhp_state hp_online; | |
e2cb2f1c | 843 | #endif |
16295bec | 844 | |
5e017dc3 DK |
845 | static void __padata_free(struct padata_instance *pinst) |
846 | { | |
847 | #ifdef CONFIG_HOTPLUG_CPU | |
30e92153 | 848 | cpuhp_state_remove_instance_nocalls(hp_online, &pinst->node); |
5e017dc3 DK |
849 | #endif |
850 | ||
851 | padata_stop(pinst); | |
852 | padata_free_pd(pinst->pd); | |
853 | free_cpumask_var(pinst->cpumask.pcpu); | |
854 | free_cpumask_var(pinst->cpumask.cbcpu); | |
855 | kfree(pinst); | |
856 | } | |
857 | ||
858 | #define kobj2pinst(_kobj) \ | |
859 | container_of(_kobj, struct padata_instance, kobj) | |
860 | #define attr2pentry(_attr) \ | |
861 | container_of(_attr, struct padata_sysfs_entry, attr) | |
862 | ||
863 | static void padata_sysfs_release(struct kobject *kobj) | |
864 | { | |
865 | struct padata_instance *pinst = kobj2pinst(kobj); | |
866 | __padata_free(pinst); | |
867 | } | |
868 | ||
869 | struct padata_sysfs_entry { | |
870 | struct attribute attr; | |
871 | ssize_t (*show)(struct padata_instance *, struct attribute *, char *); | |
872 | ssize_t (*store)(struct padata_instance *, struct attribute *, | |
873 | const char *, size_t); | |
874 | }; | |
875 | ||
876 | static ssize_t show_cpumask(struct padata_instance *pinst, | |
877 | struct attribute *attr, char *buf) | |
878 | { | |
879 | struct cpumask *cpumask; | |
880 | ssize_t len; | |
881 | ||
882 | mutex_lock(&pinst->lock); | |
883 | if (!strcmp(attr->name, "serial_cpumask")) | |
884 | cpumask = pinst->cpumask.cbcpu; | |
885 | else | |
886 | cpumask = pinst->cpumask.pcpu; | |
887 | ||
4497da6f TH |
888 | len = snprintf(buf, PAGE_SIZE, "%*pb\n", |
889 | nr_cpu_ids, cpumask_bits(cpumask)); | |
5e017dc3 | 890 | mutex_unlock(&pinst->lock); |
4497da6f | 891 | return len < PAGE_SIZE ? len : -EINVAL; |
5e017dc3 DK |
892 | } |
893 | ||
894 | static ssize_t store_cpumask(struct padata_instance *pinst, | |
895 | struct attribute *attr, | |
896 | const char *buf, size_t count) | |
897 | { | |
898 | cpumask_var_t new_cpumask; | |
899 | ssize_t ret; | |
900 | int mask_type; | |
901 | ||
902 | if (!alloc_cpumask_var(&new_cpumask, GFP_KERNEL)) | |
903 | return -ENOMEM; | |
904 | ||
905 | ret = bitmap_parse(buf, count, cpumask_bits(new_cpumask), | |
906 | nr_cpumask_bits); | |
907 | if (ret < 0) | |
908 | goto out; | |
909 | ||
910 | mask_type = !strcmp(attr->name, "serial_cpumask") ? | |
911 | PADATA_CPU_SERIAL : PADATA_CPU_PARALLEL; | |
912 | ret = padata_set_cpumask(pinst, mask_type, new_cpumask); | |
913 | if (!ret) | |
914 | ret = count; | |
915 | ||
916 | out: | |
917 | free_cpumask_var(new_cpumask); | |
918 | return ret; | |
919 | } | |
920 | ||
921 | #define PADATA_ATTR_RW(_name, _show_name, _store_name) \ | |
922 | static struct padata_sysfs_entry _name##_attr = \ | |
923 | __ATTR(_name, 0644, _show_name, _store_name) | |
924 | #define PADATA_ATTR_RO(_name, _show_name) \ | |
925 | static struct padata_sysfs_entry _name##_attr = \ | |
926 | __ATTR(_name, 0400, _show_name, NULL) | |
927 | ||
928 | PADATA_ATTR_RW(serial_cpumask, show_cpumask, store_cpumask); | |
929 | PADATA_ATTR_RW(parallel_cpumask, show_cpumask, store_cpumask); | |
930 | ||
931 | /* | |
932 | * Padata sysfs provides the following objects: | |
933 | * serial_cpumask [RW] - cpumask for serial workers | |
934 | * parallel_cpumask [RW] - cpumask for parallel workers | |
935 | */ | |
936 | static struct attribute *padata_default_attrs[] = { | |
937 | &serial_cpumask_attr.attr, | |
938 | ¶llel_cpumask_attr.attr, | |
939 | NULL, | |
940 | }; | |
941 | ||
942 | static ssize_t padata_sysfs_show(struct kobject *kobj, | |
943 | struct attribute *attr, char *buf) | |
944 | { | |
945 | struct padata_instance *pinst; | |
946 | struct padata_sysfs_entry *pentry; | |
947 | ssize_t ret = -EIO; | |
948 | ||
949 | pinst = kobj2pinst(kobj); | |
950 | pentry = attr2pentry(attr); | |
951 | if (pentry->show) | |
952 | ret = pentry->show(pinst, attr, buf); | |
953 | ||
954 | return ret; | |
955 | } | |
956 | ||
957 | static ssize_t padata_sysfs_store(struct kobject *kobj, struct attribute *attr, | |
958 | const char *buf, size_t count) | |
959 | { | |
960 | struct padata_instance *pinst; | |
961 | struct padata_sysfs_entry *pentry; | |
962 | ssize_t ret = -EIO; | |
963 | ||
964 | pinst = kobj2pinst(kobj); | |
965 | pentry = attr2pentry(attr); | |
966 | if (pentry->show) | |
967 | ret = pentry->store(pinst, attr, buf, count); | |
968 | ||
969 | return ret; | |
970 | } | |
971 | ||
972 | static const struct sysfs_ops padata_sysfs_ops = { | |
973 | .show = padata_sysfs_show, | |
974 | .store = padata_sysfs_store, | |
975 | }; | |
976 | ||
977 | static struct kobj_type padata_attr_type = { | |
978 | .sysfs_ops = &padata_sysfs_ops, | |
979 | .default_attrs = padata_default_attrs, | |
980 | .release = padata_sysfs_release, | |
981 | }; | |
982 | ||
e15bacbe | 983 | /** |
e6cc1170 SK |
984 | * padata_alloc - allocate and initialize a padata instance and specify |
985 | * cpumasks for serial and parallel workers. | |
16295bec | 986 | * |
16295bec | 987 | * @wq: workqueue to use for the allocated padata instance |
e15bacbe DK |
988 | * @pcpumask: cpumask that will be used for padata parallelization |
989 | * @cbcpumask: cpumask that will be used for padata serialization | |
c5a81c8f SAS |
990 | * |
991 | * Must be called from a cpus_read_lock() protected region | |
16295bec | 992 | */ |
9596695e TG |
993 | static struct padata_instance *padata_alloc(struct workqueue_struct *wq, |
994 | const struct cpumask *pcpumask, | |
995 | const struct cpumask *cbcpumask) | |
16295bec | 996 | { |
16295bec | 997 | struct padata_instance *pinst; |
33e54450 | 998 | struct parallel_data *pd = NULL; |
16295bec SK |
999 | |
1000 | pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL); | |
1001 | if (!pinst) | |
1002 | goto err; | |
1003 | ||
e15bacbe | 1004 | if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL)) |
16295bec | 1005 | goto err_free_inst; |
e15bacbe DK |
1006 | if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) { |
1007 | free_cpumask_var(pinst->cpumask.pcpu); | |
16295bec | 1008 | goto err_free_inst; |
33e54450 | 1009 | } |
e15bacbe DK |
1010 | if (!padata_validate_cpumask(pinst, pcpumask) || |
1011 | !padata_validate_cpumask(pinst, cbcpumask)) | |
1012 | goto err_free_masks; | |
16295bec | 1013 | |
e15bacbe DK |
1014 | pd = padata_alloc_pd(pinst, pcpumask, cbcpumask); |
1015 | if (!pd) | |
1016 | goto err_free_masks; | |
74781387 | 1017 | |
16295bec SK |
1018 | rcu_assign_pointer(pinst->pd, pd); |
1019 | ||
1020 | pinst->wq = wq; | |
1021 | ||
e15bacbe DK |
1022 | cpumask_copy(pinst->cpumask.pcpu, pcpumask); |
1023 | cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); | |
16295bec SK |
1024 | |
1025 | pinst->flags = 0; | |
1026 | ||
e15bacbe | 1027 | BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier); |
5e017dc3 | 1028 | kobject_init(&pinst->kobj, &padata_attr_type); |
16295bec SK |
1029 | mutex_init(&pinst->lock); |
1030 | ||
b8b4a416 | 1031 | #ifdef CONFIG_HOTPLUG_CPU |
c5a81c8f | 1032 | cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node); |
b8b4a416 | 1033 | #endif |
16295bec SK |
1034 | return pinst; |
1035 | ||
e15bacbe DK |
1036 | err_free_masks: |
1037 | free_cpumask_var(pinst->cpumask.pcpu); | |
1038 | free_cpumask_var(pinst->cpumask.cbcpu); | |
16295bec SK |
1039 | err_free_inst: |
1040 | kfree(pinst); | |
1041 | err: | |
1042 | return NULL; | |
1043 | } | |
16295bec | 1044 | |
9596695e TG |
1045 | /** |
1046 | * padata_alloc_possible - Allocate and initialize padata instance. | |
1047 | * Use the cpu_possible_mask for serial and | |
1048 | * parallel workers. | |
1049 | * | |
1050 | * @wq: workqueue to use for the allocated padata instance | |
c5a81c8f SAS |
1051 | * |
1052 | * Must be called from a cpus_read_lock() protected region | |
9596695e TG |
1053 | */ |
1054 | struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq) | |
1055 | { | |
c5a81c8f | 1056 | lockdep_assert_cpus_held(); |
9596695e TG |
1057 | return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask); |
1058 | } | |
1059 | EXPORT_SYMBOL(padata_alloc_possible); | |
1060 | ||
0198ffd1 | 1061 | /** |
16295bec SK |
1062 | * padata_free - free a padata instance |
1063 | * | |
0198ffd1 | 1064 | * @padata_inst: padata instance to free |
16295bec SK |
1065 | */ |
1066 | void padata_free(struct padata_instance *pinst) | |
1067 | { | |
5e017dc3 | 1068 | kobject_put(&pinst->kobj); |
16295bec SK |
1069 | } |
1070 | EXPORT_SYMBOL(padata_free); | |
30e92153 SAS |
1071 | |
1072 | #ifdef CONFIG_HOTPLUG_CPU | |
1073 | ||
1074 | static __init int padata_driver_init(void) | |
1075 | { | |
1076 | int ret; | |
1077 | ||
1078 | ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "padata:online", | |
1079 | padata_cpu_online, | |
1080 | padata_cpu_prep_down); | |
1081 | if (ret < 0) | |
1082 | return ret; | |
1083 | hp_online = ret; | |
1084 | return 0; | |
1085 | } | |
1086 | module_init(padata_driver_init); | |
1087 | ||
1088 | static __exit void padata_driver_exit(void) | |
1089 | { | |
1090 | cpuhp_remove_multi_state(hp_online); | |
1091 | } | |
1092 | module_exit(padata_driver_exit); | |
1093 | #endif |