Commit | Line | Data |
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08b21fbf | 1 | // SPDX-License-Identifier: GPL-2.0 |
16295bec SK |
2 | /* |
3 | * padata.c - generic interface to process data streams in parallel | |
4 | * | |
bfcdcef8 | 5 | * See Documentation/core-api/padata.rst for more information. |
107f8bda | 6 | * |
16295bec SK |
7 | * Copyright (C) 2008, 2009 secunet Security Networks AG |
8 | * Copyright (C) 2008, 2009 Steffen Klassert <steffen.klassert@secunet.com> | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify it | |
11 | * under the terms and conditions of the GNU General Public License, | |
12 | * version 2, as published by the Free Software Foundation. | |
13 | * | |
14 | * This program is distributed in the hope it will be useful, but WITHOUT | |
15 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
16 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
17 | * more details. | |
18 | * | |
19 | * You should have received a copy of the GNU General Public License along with | |
20 | * this program; if not, write to the Free Software Foundation, Inc., | |
21 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
22 | */ | |
23 | ||
9984de1a | 24 | #include <linux/export.h> |
16295bec SK |
25 | #include <linux/cpumask.h> |
26 | #include <linux/err.h> | |
27 | #include <linux/cpu.h> | |
28 | #include <linux/padata.h> | |
29 | #include <linux/mutex.h> | |
30 | #include <linux/sched.h> | |
5a0e3ad6 | 31 | #include <linux/slab.h> |
5e017dc3 | 32 | #include <linux/sysfs.h> |
16295bec | 33 | #include <linux/rcupdate.h> |
30e92153 | 34 | #include <linux/module.h> |
16295bec | 35 | |
97e3d94a | 36 | #define MAX_OBJ_NUM 1000 |
16295bec | 37 | |
07928d9b HX |
38 | static void padata_free_pd(struct parallel_data *pd); |
39 | ||
16295bec SK |
40 | static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index) |
41 | { | |
42 | int cpu, target_cpu; | |
43 | ||
e15bacbe | 44 | target_cpu = cpumask_first(pd->cpumask.pcpu); |
16295bec | 45 | for (cpu = 0; cpu < cpu_index; cpu++) |
e15bacbe | 46 | target_cpu = cpumask_next(target_cpu, pd->cpumask.pcpu); |
16295bec SK |
47 | |
48 | return target_cpu; | |
49 | } | |
50 | ||
bfde23ce | 51 | static int padata_cpu_hash(struct parallel_data *pd, unsigned int seq_nr) |
16295bec | 52 | { |
16295bec SK |
53 | /* |
54 | * Hash the sequence numbers to the cpus by taking | |
55 | * seq_nr mod. number of cpus in use. | |
56 | */ | |
bfde23ce | 57 | int cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu); |
16295bec SK |
58 | |
59 | return padata_index_to_cpu(pd, cpu_index); | |
60 | } | |
61 | ||
e15bacbe | 62 | static void padata_parallel_worker(struct work_struct *parallel_work) |
16295bec | 63 | { |
e15bacbe | 64 | struct padata_parallel_queue *pqueue; |
16295bec SK |
65 | LIST_HEAD(local_list); |
66 | ||
67 | local_bh_disable(); | |
e15bacbe DK |
68 | pqueue = container_of(parallel_work, |
69 | struct padata_parallel_queue, work); | |
16295bec | 70 | |
e15bacbe DK |
71 | spin_lock(&pqueue->parallel.lock); |
72 | list_replace_init(&pqueue->parallel.list, &local_list); | |
73 | spin_unlock(&pqueue->parallel.lock); | |
16295bec SK |
74 | |
75 | while (!list_empty(&local_list)) { | |
76 | struct padata_priv *padata; | |
77 | ||
78 | padata = list_entry(local_list.next, | |
79 | struct padata_priv, list); | |
80 | ||
81 | list_del_init(&padata->list); | |
82 | ||
83 | padata->parallel(padata); | |
84 | } | |
85 | ||
86 | local_bh_enable(); | |
87 | } | |
88 | ||
0198ffd1 | 89 | /** |
16295bec SK |
90 | * padata_do_parallel - padata parallelization function |
91 | * | |
bbefa1dd | 92 | * @ps: padatashell |
16295bec | 93 | * @padata: object to be parallelized |
e6ce0e08 DJ |
94 | * @cb_cpu: pointer to the CPU that the serialization callback function should |
95 | * run on. If it's not in the serial cpumask of @pinst | |
96 | * (i.e. cpumask.cbcpu), this function selects a fallback CPU and if | |
97 | * none found, returns -EINVAL. | |
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. | |
bfcdcef8 DJ |
102 | * |
103 | * Return: 0 on success or else negative error code. | |
16295bec | 104 | */ |
bbefa1dd | 105 | int padata_do_parallel(struct padata_shell *ps, |
e6ce0e08 | 106 | struct padata_priv *padata, int *cb_cpu) |
16295bec | 107 | { |
bbefa1dd | 108 | struct padata_instance *pinst = ps->pinst; |
e6ce0e08 | 109 | int i, cpu, cpu_index, target_cpu, err; |
e15bacbe | 110 | struct padata_parallel_queue *queue; |
16295bec SK |
111 | struct parallel_data *pd; |
112 | ||
113 | rcu_read_lock_bh(); | |
114 | ||
bbefa1dd | 115 | pd = rcu_dereference_bh(ps->pd); |
16295bec | 116 | |
83f619f3 | 117 | err = -EINVAL; |
7424713b | 118 | if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID) |
16295bec SK |
119 | goto out; |
120 | ||
e6ce0e08 DJ |
121 | if (!cpumask_test_cpu(*cb_cpu, pd->cpumask.cbcpu)) { |
122 | if (!cpumask_weight(pd->cpumask.cbcpu)) | |
123 | goto out; | |
124 | ||
125 | /* Select an alternate fallback CPU and notify the caller. */ | |
126 | cpu_index = *cb_cpu % cpumask_weight(pd->cpumask.cbcpu); | |
127 | ||
128 | cpu = cpumask_first(pd->cpumask.cbcpu); | |
129 | for (i = 0; i < cpu_index; i++) | |
130 | cpu = cpumask_next(cpu, pd->cpumask.cbcpu); | |
131 | ||
132 | *cb_cpu = cpu; | |
133 | } | |
16295bec SK |
134 | |
135 | err = -EBUSY; | |
136 | if ((pinst->flags & PADATA_RESET)) | |
137 | goto out; | |
138 | ||
139 | if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM) | |
140 | goto out; | |
141 | ||
83f619f3 | 142 | err = 0; |
16295bec SK |
143 | atomic_inc(&pd->refcnt); |
144 | padata->pd = pd; | |
e6ce0e08 | 145 | padata->cb_cpu = *cb_cpu; |
16295bec | 146 | |
bfde23ce DJ |
147 | padata->seq_nr = atomic_inc_return(&pd->seq_nr); |
148 | target_cpu = padata_cpu_hash(pd, padata->seq_nr); | |
350ef88e | 149 | padata->cpu = target_cpu; |
e15bacbe | 150 | queue = per_cpu_ptr(pd->pqueue, target_cpu); |
16295bec SK |
151 | |
152 | spin_lock(&queue->parallel.lock); | |
153 | list_add_tail(&padata->list, &queue->parallel.list); | |
154 | spin_unlock(&queue->parallel.lock); | |
155 | ||
bfde23ce | 156 | queue_work(pinst->parallel_wq, &queue->work); |
16295bec SK |
157 | |
158 | out: | |
159 | rcu_read_unlock_bh(); | |
160 | ||
161 | return err; | |
162 | } | |
163 | EXPORT_SYMBOL(padata_do_parallel); | |
164 | ||
0198ffd1 | 165 | /* |
bfde23ce | 166 | * padata_find_next - Find the next object that needs serialization. |
0198ffd1 | 167 | * |
bfcdcef8 DJ |
168 | * Return: |
169 | * * A pointer to the control struct of the next object that needs | |
170 | * serialization, if present in one of the percpu reorder queues. | |
171 | * * NULL, if the next object that needs serialization will | |
172 | * be parallel processed by another cpu and is not yet present in | |
173 | * the cpu's reorder queue. | |
0198ffd1 | 174 | */ |
bfde23ce DJ |
175 | static struct padata_priv *padata_find_next(struct parallel_data *pd, |
176 | bool remove_object) | |
16295bec | 177 | { |
f0fcf200 | 178 | struct padata_parallel_queue *next_queue; |
16295bec SK |
179 | struct padata_priv *padata; |
180 | struct padata_list *reorder; | |
6fc4dbcf | 181 | int cpu = pd->cpu; |
16295bec | 182 | |
e15bacbe | 183 | next_queue = per_cpu_ptr(pd->pqueue, cpu); |
16295bec SK |
184 | reorder = &next_queue->reorder; |
185 | ||
de5540d0 | 186 | spin_lock(&reorder->lock); |
bfde23ce DJ |
187 | if (list_empty(&reorder->list)) { |
188 | spin_unlock(&reorder->lock); | |
189 | return NULL; | |
190 | } | |
16295bec | 191 | |
bfde23ce | 192 | padata = list_entry(reorder->list.next, struct padata_priv, list); |
16295bec | 193 | |
bfde23ce DJ |
194 | /* |
195 | * Checks the rare case where two or more parallel jobs have hashed to | |
196 | * the same CPU and one of the later ones finishes first. | |
197 | */ | |
198 | if (padata->seq_nr != pd->processed) { | |
de5540d0 | 199 | spin_unlock(&reorder->lock); |
bfde23ce | 200 | return NULL; |
16295bec SK |
201 | } |
202 | ||
bfde23ce DJ |
203 | if (remove_object) { |
204 | list_del_init(&padata->list); | |
bfde23ce DJ |
205 | ++pd->processed; |
206 | pd->cpu = cpumask_next_wrap(cpu, pd->cpumask.pcpu, -1, false); | |
16295bec SK |
207 | } |
208 | ||
bfde23ce | 209 | spin_unlock(&reorder->lock); |
16295bec SK |
210 | return padata; |
211 | } | |
212 | ||
213 | static void padata_reorder(struct parallel_data *pd) | |
214 | { | |
bbefa1dd | 215 | struct padata_instance *pinst = pd->ps->pinst; |
3047817b | 216 | int cb_cpu; |
16295bec | 217 | struct padata_priv *padata; |
e15bacbe | 218 | struct padata_serial_queue *squeue; |
6fc4dbcf | 219 | struct padata_parallel_queue *next_queue; |
16295bec | 220 | |
0198ffd1 SK |
221 | /* |
222 | * We need to ensure that only one cpu can work on dequeueing of | |
223 | * the reorder queue the time. Calculating in which percpu reorder | |
224 | * queue the next object will arrive takes some time. A spinlock | |
225 | * would be highly contended. Also it is not clear in which order | |
226 | * the objects arrive to the reorder queues. So a cpu could wait to | |
227 | * get the lock just to notice that there is nothing to do at the | |
228 | * moment. Therefore we use a trylock and let the holder of the lock | |
229 | * care for all the objects enqueued during the holdtime of the lock. | |
230 | */ | |
16295bec | 231 | if (!spin_trylock_bh(&pd->lock)) |
d46a5ac7 | 232 | return; |
16295bec SK |
233 | |
234 | while (1) { | |
bfde23ce | 235 | padata = padata_find_next(pd, true); |
16295bec | 236 | |
0198ffd1 | 237 | /* |
69b34844 JD |
238 | * If the next object that needs serialization is parallel |
239 | * processed by another cpu and is still on it's way to the | |
240 | * cpu's reorder queue, nothing to do for now. | |
0198ffd1 | 241 | */ |
bfde23ce | 242 | if (!padata) |
16295bec SK |
243 | break; |
244 | ||
3047817b SK |
245 | cb_cpu = padata->cb_cpu; |
246 | squeue = per_cpu_ptr(pd->squeue, cb_cpu); | |
16295bec | 247 | |
e15bacbe DK |
248 | spin_lock(&squeue->serial.lock); |
249 | list_add_tail(&padata->list, &squeue->serial.list); | |
250 | spin_unlock(&squeue->serial.lock); | |
16295bec | 251 | |
45d153c0 | 252 | queue_work_on(cb_cpu, pinst->serial_wq, &squeue->work); |
16295bec SK |
253 | } |
254 | ||
255 | spin_unlock_bh(&pd->lock); | |
256 | ||
0198ffd1 SK |
257 | /* |
258 | * The next object that needs serialization might have arrived to | |
6fc4dbcf | 259 | * the reorder queues in the meantime. |
cf144f81 | 260 | * |
6fc4dbcf HX |
261 | * Ensure reorder queue is read after pd->lock is dropped so we see |
262 | * new objects from another task in padata_do_serial. Pairs with | |
cf144f81 | 263 | * smp_mb__after_atomic in padata_do_serial. |
0198ffd1 | 264 | */ |
cf144f81 | 265 | smp_mb(); |
16295bec | 266 | |
6fc4dbcf | 267 | next_queue = per_cpu_ptr(pd->pqueue, pd->cpu); |
bfde23ce DJ |
268 | if (!list_empty(&next_queue->reorder.list) && |
269 | padata_find_next(pd, false)) | |
45d153c0 | 270 | queue_work(pinst->serial_wq, &pd->reorder_work); |
16295bec SK |
271 | } |
272 | ||
cf5868c8 MK |
273 | static void invoke_padata_reorder(struct work_struct *work) |
274 | { | |
cf5868c8 MK |
275 | struct parallel_data *pd; |
276 | ||
277 | local_bh_disable(); | |
6fc4dbcf | 278 | pd = container_of(work, struct parallel_data, reorder_work); |
cf5868c8 MK |
279 | padata_reorder(pd); |
280 | local_bh_enable(); | |
281 | } | |
282 | ||
e15bacbe | 283 | static void padata_serial_worker(struct work_struct *serial_work) |
16295bec | 284 | { |
e15bacbe | 285 | struct padata_serial_queue *squeue; |
16295bec SK |
286 | struct parallel_data *pd; |
287 | LIST_HEAD(local_list); | |
07928d9b | 288 | int cnt; |
16295bec SK |
289 | |
290 | local_bh_disable(); | |
e15bacbe DK |
291 | squeue = container_of(serial_work, struct padata_serial_queue, work); |
292 | pd = squeue->pd; | |
16295bec | 293 | |
e15bacbe DK |
294 | spin_lock(&squeue->serial.lock); |
295 | list_replace_init(&squeue->serial.list, &local_list); | |
296 | spin_unlock(&squeue->serial.lock); | |
16295bec | 297 | |
07928d9b HX |
298 | cnt = 0; |
299 | ||
16295bec SK |
300 | while (!list_empty(&local_list)) { |
301 | struct padata_priv *padata; | |
302 | ||
303 | padata = list_entry(local_list.next, | |
304 | struct padata_priv, list); | |
305 | ||
306 | list_del_init(&padata->list); | |
307 | ||
308 | padata->serial(padata); | |
07928d9b | 309 | cnt++; |
16295bec SK |
310 | } |
311 | local_bh_enable(); | |
07928d9b HX |
312 | |
313 | if (atomic_sub_and_test(cnt, &pd->refcnt)) | |
314 | padata_free_pd(pd); | |
16295bec SK |
315 | } |
316 | ||
0198ffd1 | 317 | /** |
16295bec SK |
318 | * padata_do_serial - padata serialization function |
319 | * | |
320 | * @padata: object to be serialized. | |
321 | * | |
322 | * padata_do_serial must be called for every parallelized object. | |
323 | * The serialization callback function will run with BHs off. | |
324 | */ | |
325 | void padata_do_serial(struct padata_priv *padata) | |
326 | { | |
065cf577 DJ |
327 | struct parallel_data *pd = padata->pd; |
328 | struct padata_parallel_queue *pqueue = per_cpu_ptr(pd->pqueue, | |
329 | padata->cpu); | |
bfde23ce | 330 | struct padata_priv *cur; |
16295bec | 331 | |
e15bacbe | 332 | spin_lock(&pqueue->reorder.lock); |
bfde23ce DJ |
333 | /* Sort in ascending order of sequence number. */ |
334 | list_for_each_entry_reverse(cur, &pqueue->reorder.list, list) | |
335 | if (cur->seq_nr < padata->seq_nr) | |
336 | break; | |
337 | list_add(&padata->list, &cur->list); | |
e15bacbe | 338 | spin_unlock(&pqueue->reorder.lock); |
16295bec | 339 | |
cf144f81 | 340 | /* |
6fc4dbcf | 341 | * Ensure the addition to the reorder list is ordered correctly |
cf144f81 DJ |
342 | * with the trylock of pd->lock in padata_reorder. Pairs with smp_mb |
343 | * in padata_reorder. | |
344 | */ | |
345 | smp_mb__after_atomic(); | |
346 | ||
6fc4dbcf | 347 | padata_reorder(pd); |
16295bec SK |
348 | } |
349 | EXPORT_SYMBOL(padata_do_serial); | |
350 | ||
bbefa1dd | 351 | static int padata_setup_cpumasks(struct padata_instance *pinst) |
16295bec | 352 | { |
bfde23ce | 353 | struct workqueue_attrs *attrs; |
bbefa1dd HX |
354 | int err; |
355 | ||
356 | attrs = alloc_workqueue_attrs(); | |
357 | if (!attrs) | |
358 | return -ENOMEM; | |
359 | ||
360 | /* Restrict parallel_wq workers to pd->cpumask.pcpu. */ | |
361 | cpumask_copy(attrs->cpumask, pinst->cpumask.pcpu); | |
362 | err = apply_workqueue_attrs(pinst->parallel_wq, attrs); | |
363 | free_workqueue_attrs(attrs); | |
364 | ||
365 | return err; | |
366 | } | |
367 | ||
368 | static int pd_setup_cpumasks(struct parallel_data *pd, | |
369 | const struct cpumask *pcpumask, | |
370 | const struct cpumask *cbcpumask) | |
371 | { | |
bfde23ce | 372 | int err = -ENOMEM; |
16295bec | 373 | |
bfde23ce DJ |
374 | if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL)) |
375 | goto out; | |
bfde23ce DJ |
376 | if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) |
377 | goto free_pcpu_mask; | |
bfde23ce | 378 | |
bbefa1dd HX |
379 | cpumask_copy(pd->cpumask.pcpu, pcpumask); |
380 | cpumask_copy(pd->cpumask.cbcpu, cbcpumask); | |
bfde23ce | 381 | |
e15bacbe | 382 | return 0; |
bfde23ce | 383 | |
bfde23ce DJ |
384 | free_pcpu_mask: |
385 | free_cpumask_var(pd->cpumask.pcpu); | |
386 | out: | |
387 | return err; | |
e15bacbe | 388 | } |
16295bec | 389 | |
e15bacbe DK |
390 | static void __padata_list_init(struct padata_list *pd_list) |
391 | { | |
392 | INIT_LIST_HEAD(&pd_list->list); | |
393 | spin_lock_init(&pd_list->lock); | |
394 | } | |
16295bec | 395 | |
e15bacbe DK |
396 | /* Initialize all percpu queues used by serial workers */ |
397 | static void padata_init_squeues(struct parallel_data *pd) | |
398 | { | |
399 | int cpu; | |
400 | struct padata_serial_queue *squeue; | |
7b389b2c | 401 | |
e15bacbe DK |
402 | for_each_cpu(cpu, pd->cpumask.cbcpu) { |
403 | squeue = per_cpu_ptr(pd->squeue, cpu); | |
404 | squeue->pd = pd; | |
405 | __padata_list_init(&squeue->serial); | |
406 | INIT_WORK(&squeue->work, padata_serial_worker); | |
407 | } | |
408 | } | |
16295bec | 409 | |
e15bacbe DK |
410 | /* Initialize all percpu queues used by parallel workers */ |
411 | static void padata_init_pqueues(struct parallel_data *pd) | |
412 | { | |
c51636a3 | 413 | int cpu; |
e15bacbe | 414 | struct padata_parallel_queue *pqueue; |
16295bec | 415 | |
c51636a3 | 416 | for_each_cpu(cpu, pd->cpumask.pcpu) { |
e15bacbe | 417 | pqueue = per_cpu_ptr(pd->pqueue, cpu); |
1bd845bc | 418 | |
e15bacbe DK |
419 | __padata_list_init(&pqueue->reorder); |
420 | __padata_list_init(&pqueue->parallel); | |
421 | INIT_WORK(&pqueue->work, padata_parallel_worker); | |
422 | atomic_set(&pqueue->num_obj, 0); | |
16295bec | 423 | } |
e15bacbe | 424 | } |
16295bec | 425 | |
e15bacbe | 426 | /* Allocate and initialize the internal cpumask dependend resources. */ |
bbefa1dd | 427 | static struct parallel_data *padata_alloc_pd(struct padata_shell *ps) |
e15bacbe | 428 | { |
bbefa1dd HX |
429 | struct padata_instance *pinst = ps->pinst; |
430 | const struct cpumask *cbcpumask; | |
431 | const struct cpumask *pcpumask; | |
e15bacbe | 432 | struct parallel_data *pd; |
16295bec | 433 | |
bbefa1dd HX |
434 | cbcpumask = pinst->rcpumask.cbcpu; |
435 | pcpumask = pinst->rcpumask.pcpu; | |
436 | ||
e15bacbe DK |
437 | pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL); |
438 | if (!pd) | |
439 | goto err; | |
16295bec | 440 | |
e15bacbe DK |
441 | pd->pqueue = alloc_percpu(struct padata_parallel_queue); |
442 | if (!pd->pqueue) | |
443 | goto err_free_pd; | |
444 | ||
445 | pd->squeue = alloc_percpu(struct padata_serial_queue); | |
446 | if (!pd->squeue) | |
447 | goto err_free_pqueue; | |
bfde23ce | 448 | |
bbefa1dd HX |
449 | pd->ps = ps; |
450 | if (pd_setup_cpumasks(pd, pcpumask, cbcpumask)) | |
e15bacbe | 451 | goto err_free_squeue; |
16295bec | 452 | |
e15bacbe DK |
453 | padata_init_pqueues(pd); |
454 | padata_init_squeues(pd); | |
0b6b098e | 455 | atomic_set(&pd->seq_nr, -1); |
07928d9b | 456 | atomic_set(&pd->refcnt, 1); |
16295bec | 457 | spin_lock_init(&pd->lock); |
ec9c7d19 | 458 | pd->cpu = cpumask_first(pd->cpumask.pcpu); |
6fc4dbcf | 459 | INIT_WORK(&pd->reorder_work, invoke_padata_reorder); |
16295bec SK |
460 | |
461 | return pd; | |
462 | ||
e15bacbe DK |
463 | err_free_squeue: |
464 | free_percpu(pd->squeue); | |
465 | err_free_pqueue: | |
466 | free_percpu(pd->pqueue); | |
16295bec SK |
467 | err_free_pd: |
468 | kfree(pd); | |
469 | err: | |
470 | return NULL; | |
471 | } | |
472 | ||
473 | static void padata_free_pd(struct parallel_data *pd) | |
474 | { | |
e15bacbe DK |
475 | free_cpumask_var(pd->cpumask.pcpu); |
476 | free_cpumask_var(pd->cpumask.cbcpu); | |
477 | free_percpu(pd->pqueue); | |
478 | free_percpu(pd->squeue); | |
16295bec SK |
479 | kfree(pd); |
480 | } | |
481 | ||
4c879170 SK |
482 | static void __padata_start(struct padata_instance *pinst) |
483 | { | |
484 | pinst->flags |= PADATA_INIT; | |
485 | } | |
486 | ||
ee836555 SK |
487 | static void __padata_stop(struct padata_instance *pinst) |
488 | { | |
489 | if (!(pinst->flags & PADATA_INIT)) | |
490 | return; | |
491 | ||
492 | pinst->flags &= ~PADATA_INIT; | |
493 | ||
494 | synchronize_rcu(); | |
ee836555 SK |
495 | } |
496 | ||
25985edc | 497 | /* Replace the internal control structure with a new one. */ |
bbefa1dd | 498 | static int padata_replace_one(struct padata_shell *ps) |
16295bec | 499 | { |
bbefa1dd | 500 | struct parallel_data *pd_new; |
16295bec | 501 | |
bbefa1dd HX |
502 | pd_new = padata_alloc_pd(ps); |
503 | if (!pd_new) | |
504 | return -ENOMEM; | |
16295bec | 505 | |
bbefa1dd HX |
506 | ps->opd = rcu_dereference_protected(ps->pd, 1); |
507 | rcu_assign_pointer(ps->pd, pd_new); | |
16295bec | 508 | |
bbefa1dd HX |
509 | return 0; |
510 | } | |
511 | ||
894c9ef9 | 512 | static int padata_replace(struct padata_instance *pinst) |
bbefa1dd | 513 | { |
bbefa1dd HX |
514 | struct padata_shell *ps; |
515 | int err; | |
516 | ||
517 | pinst->flags |= PADATA_RESET; | |
16295bec | 518 | |
bbefa1dd HX |
519 | cpumask_and(pinst->rcpumask.pcpu, pinst->cpumask.pcpu, |
520 | cpu_online_mask); | |
bbefa1dd | 521 | |
bbefa1dd HX |
522 | cpumask_and(pinst->rcpumask.cbcpu, pinst->cpumask.cbcpu, |
523 | cpu_online_mask); | |
e15bacbe | 524 | |
bbefa1dd HX |
525 | list_for_each_entry(ps, &pinst->pslist, list) { |
526 | err = padata_replace_one(ps); | |
527 | if (err) | |
528 | break; | |
529 | } | |
530 | ||
531 | synchronize_rcu(); | |
532 | ||
533 | list_for_each_entry_continue_reverse(ps, &pinst->pslist, list) | |
534 | if (atomic_dec_and_test(&ps->opd->refcnt)) | |
535 | padata_free_pd(ps->opd); | |
16295bec SK |
536 | |
537 | pinst->flags &= ~PADATA_RESET; | |
bbefa1dd HX |
538 | |
539 | return err; | |
16295bec SK |
540 | } |
541 | ||
33e54450 SK |
542 | /* If cpumask contains no active cpu, we mark the instance as invalid. */ |
543 | static bool padata_validate_cpumask(struct padata_instance *pinst, | |
544 | const struct cpumask *cpumask) | |
545 | { | |
13614e0f | 546 | if (!cpumask_intersects(cpumask, cpu_online_mask)) { |
33e54450 SK |
547 | pinst->flags |= PADATA_INVALID; |
548 | return false; | |
549 | } | |
550 | ||
551 | pinst->flags &= ~PADATA_INVALID; | |
552 | return true; | |
553 | } | |
554 | ||
65ff577e SK |
555 | static int __padata_set_cpumasks(struct padata_instance *pinst, |
556 | cpumask_var_t pcpumask, | |
557 | cpumask_var_t cbcpumask) | |
558 | { | |
559 | int valid; | |
bbefa1dd | 560 | int err; |
65ff577e SK |
561 | |
562 | valid = padata_validate_cpumask(pinst, pcpumask); | |
563 | if (!valid) { | |
564 | __padata_stop(pinst); | |
565 | goto out_replace; | |
566 | } | |
567 | ||
568 | valid = padata_validate_cpumask(pinst, cbcpumask); | |
569 | if (!valid) | |
570 | __padata_stop(pinst); | |
571 | ||
572 | out_replace: | |
65ff577e SK |
573 | cpumask_copy(pinst->cpumask.pcpu, pcpumask); |
574 | cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); | |
575 | ||
894c9ef9 | 576 | err = padata_setup_cpumasks(pinst) ?: padata_replace(pinst); |
65ff577e SK |
577 | |
578 | if (valid) | |
579 | __padata_start(pinst); | |
580 | ||
bbefa1dd | 581 | return err; |
65ff577e SK |
582 | } |
583 | ||
e15bacbe | 584 | /** |
bfcdcef8 DJ |
585 | * padata_set_cpumask - Sets specified by @cpumask_type cpumask to the value |
586 | * equivalent to @cpumask. | |
16295bec | 587 | * @pinst: padata instance |
e15bacbe DK |
588 | * @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding |
589 | * to parallel and serial cpumasks respectively. | |
16295bec | 590 | * @cpumask: the cpumask to use |
bfcdcef8 DJ |
591 | * |
592 | * Return: 0 on success or negative error code | |
16295bec | 593 | */ |
e15bacbe DK |
594 | int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type, |
595 | cpumask_var_t cpumask) | |
596 | { | |
597 | struct cpumask *serial_mask, *parallel_mask; | |
65ff577e SK |
598 | int err = -EINVAL; |
599 | ||
6751fb3c | 600 | get_online_cpus(); |
38228e88 | 601 | mutex_lock(&pinst->lock); |
6751fb3c | 602 | |
e15bacbe DK |
603 | switch (cpumask_type) { |
604 | case PADATA_CPU_PARALLEL: | |
605 | serial_mask = pinst->cpumask.cbcpu; | |
606 | parallel_mask = cpumask; | |
607 | break; | |
608 | case PADATA_CPU_SERIAL: | |
609 | parallel_mask = pinst->cpumask.pcpu; | |
610 | serial_mask = cpumask; | |
611 | break; | |
612 | default: | |
65ff577e | 613 | goto out; |
16295bec SK |
614 | } |
615 | ||
65ff577e | 616 | err = __padata_set_cpumasks(pinst, parallel_mask, serial_mask); |
16295bec SK |
617 | |
618 | out: | |
619 | mutex_unlock(&pinst->lock); | |
38228e88 | 620 | put_online_cpus(); |
16295bec SK |
621 | |
622 | return err; | |
623 | } | |
624 | EXPORT_SYMBOL(padata_set_cpumask); | |
625 | ||
19d795b6 AB |
626 | /** |
627 | * padata_start - start the parallel processing | |
628 | * | |
629 | * @pinst: padata instance to start | |
bfcdcef8 DJ |
630 | * |
631 | * Return: 0 on success or negative error code | |
19d795b6 AB |
632 | */ |
633 | int padata_start(struct padata_instance *pinst) | |
634 | { | |
635 | int err = 0; | |
636 | ||
637 | mutex_lock(&pinst->lock); | |
638 | ||
639 | if (pinst->flags & PADATA_INVALID) | |
640 | err = -EINVAL; | |
641 | ||
8ddab428 | 642 | __padata_start(pinst); |
19d795b6 AB |
643 | |
644 | mutex_unlock(&pinst->lock); | |
645 | ||
646 | return err; | |
647 | } | |
648 | EXPORT_SYMBOL(padata_start); | |
649 | ||
650 | /** | |
651 | * padata_stop - stop the parallel processing | |
652 | * | |
653 | * @pinst: padata instance to stop | |
654 | */ | |
655 | void padata_stop(struct padata_instance *pinst) | |
656 | { | |
657 | mutex_lock(&pinst->lock); | |
658 | __padata_stop(pinst); | |
659 | mutex_unlock(&pinst->lock); | |
660 | } | |
661 | EXPORT_SYMBOL(padata_stop); | |
662 | ||
663 | #ifdef CONFIG_HOTPLUG_CPU | |
664 | ||
16295bec SK |
665 | static int __padata_add_cpu(struct padata_instance *pinst, int cpu) |
666 | { | |
bbefa1dd | 667 | int err = 0; |
16295bec | 668 | |
13614e0f | 669 | if (cpumask_test_cpu(cpu, cpu_online_mask)) { |
894c9ef9 | 670 | err = padata_replace(pinst); |
33e54450 | 671 | |
e15bacbe DK |
672 | if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) && |
673 | padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) | |
33e54450 | 674 | __padata_start(pinst); |
16295bec SK |
675 | } |
676 | ||
bbefa1dd | 677 | return err; |
16295bec SK |
678 | } |
679 | ||
16295bec SK |
680 | static int __padata_remove_cpu(struct padata_instance *pinst, int cpu) |
681 | { | |
bbefa1dd | 682 | int err = 0; |
16295bec | 683 | |
894c9ef9 | 684 | if (!cpumask_test_cpu(cpu, cpu_online_mask)) { |
e15bacbe | 685 | if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) || |
b89661df | 686 | !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) |
33e54450 | 687 | __padata_stop(pinst); |
33e54450 | 688 | |
894c9ef9 | 689 | err = padata_replace(pinst); |
16295bec SK |
690 | } |
691 | ||
bbefa1dd | 692 | return err; |
16295bec SK |
693 | } |
694 | ||
e15bacbe DK |
695 | static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu) |
696 | { | |
697 | return cpumask_test_cpu(cpu, pinst->cpumask.pcpu) || | |
698 | cpumask_test_cpu(cpu, pinst->cpumask.cbcpu); | |
699 | } | |
700 | ||
30e92153 | 701 | static int padata_cpu_online(unsigned int cpu, struct hlist_node *node) |
16295bec | 702 | { |
16295bec | 703 | struct padata_instance *pinst; |
30e92153 | 704 | int ret; |
16295bec | 705 | |
30e92153 SAS |
706 | pinst = hlist_entry_safe(node, struct padata_instance, node); |
707 | if (!pinst_has_cpu(pinst, cpu)) | |
708 | return 0; | |
16295bec | 709 | |
30e92153 SAS |
710 | mutex_lock(&pinst->lock); |
711 | ret = __padata_add_cpu(pinst, cpu); | |
712 | mutex_unlock(&pinst->lock); | |
713 | return ret; | |
714 | } | |
16295bec | 715 | |
894c9ef9 | 716 | static int padata_cpu_dead(unsigned int cpu, struct hlist_node *node) |
30e92153 SAS |
717 | { |
718 | struct padata_instance *pinst; | |
719 | int ret; | |
720 | ||
721 | pinst = hlist_entry_safe(node, struct padata_instance, node); | |
722 | if (!pinst_has_cpu(pinst, cpu)) | |
723 | return 0; | |
16295bec | 724 | |
30e92153 SAS |
725 | mutex_lock(&pinst->lock); |
726 | ret = __padata_remove_cpu(pinst, cpu); | |
727 | mutex_unlock(&pinst->lock); | |
728 | return ret; | |
16295bec | 729 | } |
30e92153 SAS |
730 | |
731 | static enum cpuhp_state hp_online; | |
e2cb2f1c | 732 | #endif |
16295bec | 733 | |
5e017dc3 DK |
734 | static void __padata_free(struct padata_instance *pinst) |
735 | { | |
736 | #ifdef CONFIG_HOTPLUG_CPU | |
894c9ef9 | 737 | cpuhp_state_remove_instance_nocalls(CPUHP_PADATA_DEAD, &pinst->node); |
30e92153 | 738 | cpuhp_state_remove_instance_nocalls(hp_online, &pinst->node); |
5e017dc3 DK |
739 | #endif |
740 | ||
bbefa1dd HX |
741 | WARN_ON(!list_empty(&pinst->pslist)); |
742 | ||
5e017dc3 | 743 | padata_stop(pinst); |
bbefa1dd HX |
744 | free_cpumask_var(pinst->rcpumask.cbcpu); |
745 | free_cpumask_var(pinst->rcpumask.pcpu); | |
5e017dc3 DK |
746 | free_cpumask_var(pinst->cpumask.pcpu); |
747 | free_cpumask_var(pinst->cpumask.cbcpu); | |
45d153c0 DJ |
748 | destroy_workqueue(pinst->serial_wq); |
749 | destroy_workqueue(pinst->parallel_wq); | |
5e017dc3 DK |
750 | kfree(pinst); |
751 | } | |
752 | ||
753 | #define kobj2pinst(_kobj) \ | |
754 | container_of(_kobj, struct padata_instance, kobj) | |
755 | #define attr2pentry(_attr) \ | |
756 | container_of(_attr, struct padata_sysfs_entry, attr) | |
757 | ||
758 | static void padata_sysfs_release(struct kobject *kobj) | |
759 | { | |
760 | struct padata_instance *pinst = kobj2pinst(kobj); | |
761 | __padata_free(pinst); | |
762 | } | |
763 | ||
764 | struct padata_sysfs_entry { | |
765 | struct attribute attr; | |
766 | ssize_t (*show)(struct padata_instance *, struct attribute *, char *); | |
767 | ssize_t (*store)(struct padata_instance *, struct attribute *, | |
768 | const char *, size_t); | |
769 | }; | |
770 | ||
771 | static ssize_t show_cpumask(struct padata_instance *pinst, | |
772 | struct attribute *attr, char *buf) | |
773 | { | |
774 | struct cpumask *cpumask; | |
775 | ssize_t len; | |
776 | ||
777 | mutex_lock(&pinst->lock); | |
778 | if (!strcmp(attr->name, "serial_cpumask")) | |
779 | cpumask = pinst->cpumask.cbcpu; | |
780 | else | |
781 | cpumask = pinst->cpumask.pcpu; | |
782 | ||
4497da6f TH |
783 | len = snprintf(buf, PAGE_SIZE, "%*pb\n", |
784 | nr_cpu_ids, cpumask_bits(cpumask)); | |
5e017dc3 | 785 | mutex_unlock(&pinst->lock); |
4497da6f | 786 | return len < PAGE_SIZE ? len : -EINVAL; |
5e017dc3 DK |
787 | } |
788 | ||
789 | static ssize_t store_cpumask(struct padata_instance *pinst, | |
790 | struct attribute *attr, | |
791 | const char *buf, size_t count) | |
792 | { | |
793 | cpumask_var_t new_cpumask; | |
794 | ssize_t ret; | |
795 | int mask_type; | |
796 | ||
797 | if (!alloc_cpumask_var(&new_cpumask, GFP_KERNEL)) | |
798 | return -ENOMEM; | |
799 | ||
800 | ret = bitmap_parse(buf, count, cpumask_bits(new_cpumask), | |
801 | nr_cpumask_bits); | |
802 | if (ret < 0) | |
803 | goto out; | |
804 | ||
805 | mask_type = !strcmp(attr->name, "serial_cpumask") ? | |
806 | PADATA_CPU_SERIAL : PADATA_CPU_PARALLEL; | |
807 | ret = padata_set_cpumask(pinst, mask_type, new_cpumask); | |
808 | if (!ret) | |
809 | ret = count; | |
810 | ||
811 | out: | |
812 | free_cpumask_var(new_cpumask); | |
813 | return ret; | |
814 | } | |
815 | ||
816 | #define PADATA_ATTR_RW(_name, _show_name, _store_name) \ | |
817 | static struct padata_sysfs_entry _name##_attr = \ | |
818 | __ATTR(_name, 0644, _show_name, _store_name) | |
819 | #define PADATA_ATTR_RO(_name, _show_name) \ | |
820 | static struct padata_sysfs_entry _name##_attr = \ | |
821 | __ATTR(_name, 0400, _show_name, NULL) | |
822 | ||
823 | PADATA_ATTR_RW(serial_cpumask, show_cpumask, store_cpumask); | |
824 | PADATA_ATTR_RW(parallel_cpumask, show_cpumask, store_cpumask); | |
825 | ||
826 | /* | |
827 | * Padata sysfs provides the following objects: | |
828 | * serial_cpumask [RW] - cpumask for serial workers | |
829 | * parallel_cpumask [RW] - cpumask for parallel workers | |
830 | */ | |
831 | static struct attribute *padata_default_attrs[] = { | |
832 | &serial_cpumask_attr.attr, | |
833 | ¶llel_cpumask_attr.attr, | |
834 | NULL, | |
835 | }; | |
2064fbc7 | 836 | ATTRIBUTE_GROUPS(padata_default); |
5e017dc3 DK |
837 | |
838 | static ssize_t padata_sysfs_show(struct kobject *kobj, | |
839 | struct attribute *attr, char *buf) | |
840 | { | |
841 | struct padata_instance *pinst; | |
842 | struct padata_sysfs_entry *pentry; | |
843 | ssize_t ret = -EIO; | |
844 | ||
845 | pinst = kobj2pinst(kobj); | |
846 | pentry = attr2pentry(attr); | |
847 | if (pentry->show) | |
848 | ret = pentry->show(pinst, attr, buf); | |
849 | ||
850 | return ret; | |
851 | } | |
852 | ||
853 | static ssize_t padata_sysfs_store(struct kobject *kobj, struct attribute *attr, | |
854 | const char *buf, size_t count) | |
855 | { | |
856 | struct padata_instance *pinst; | |
857 | struct padata_sysfs_entry *pentry; | |
858 | ssize_t ret = -EIO; | |
859 | ||
860 | pinst = kobj2pinst(kobj); | |
861 | pentry = attr2pentry(attr); | |
862 | if (pentry->show) | |
863 | ret = pentry->store(pinst, attr, buf, count); | |
864 | ||
865 | return ret; | |
866 | } | |
867 | ||
868 | static const struct sysfs_ops padata_sysfs_ops = { | |
869 | .show = padata_sysfs_show, | |
870 | .store = padata_sysfs_store, | |
871 | }; | |
872 | ||
873 | static struct kobj_type padata_attr_type = { | |
874 | .sysfs_ops = &padata_sysfs_ops, | |
2064fbc7 | 875 | .default_groups = padata_default_groups, |
5e017dc3 DK |
876 | .release = padata_sysfs_release, |
877 | }; | |
878 | ||
e15bacbe | 879 | /** |
e6cc1170 SK |
880 | * padata_alloc - allocate and initialize a padata instance and specify |
881 | * cpumasks for serial and parallel workers. | |
16295bec | 882 | * |
b128a304 | 883 | * @name: used to identify the instance |
e15bacbe DK |
884 | * @pcpumask: cpumask that will be used for padata parallelization |
885 | * @cbcpumask: cpumask that will be used for padata serialization | |
bfcdcef8 DJ |
886 | * |
887 | * Return: new instance on success, NULL on error | |
16295bec | 888 | */ |
b128a304 | 889 | static struct padata_instance *padata_alloc(const char *name, |
9596695e TG |
890 | const struct cpumask *pcpumask, |
891 | const struct cpumask *cbcpumask) | |
16295bec | 892 | { |
16295bec | 893 | struct padata_instance *pinst; |
16295bec SK |
894 | |
895 | pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL); | |
896 | if (!pinst) | |
897 | goto err; | |
898 | ||
bfde23ce DJ |
899 | pinst->parallel_wq = alloc_workqueue("%s_parallel", WQ_UNBOUND, 0, |
900 | name); | |
45d153c0 | 901 | if (!pinst->parallel_wq) |
16295bec | 902 | goto err_free_inst; |
b128a304 | 903 | |
cc491d8e DJ |
904 | get_online_cpus(); |
905 | ||
45d153c0 DJ |
906 | pinst->serial_wq = alloc_workqueue("%s_serial", WQ_MEM_RECLAIM | |
907 | WQ_CPU_INTENSIVE, 1, name); | |
908 | if (!pinst->serial_wq) | |
cc491d8e | 909 | goto err_put_cpus; |
45d153c0 DJ |
910 | |
911 | if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL)) | |
912 | goto err_free_serial_wq; | |
e15bacbe DK |
913 | if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) { |
914 | free_cpumask_var(pinst->cpumask.pcpu); | |
45d153c0 | 915 | goto err_free_serial_wq; |
33e54450 | 916 | } |
e15bacbe DK |
917 | if (!padata_validate_cpumask(pinst, pcpumask) || |
918 | !padata_validate_cpumask(pinst, cbcpumask)) | |
919 | goto err_free_masks; | |
16295bec | 920 | |
bbefa1dd | 921 | if (!alloc_cpumask_var(&pinst->rcpumask.pcpu, GFP_KERNEL)) |
e15bacbe | 922 | goto err_free_masks; |
bbefa1dd HX |
923 | if (!alloc_cpumask_var(&pinst->rcpumask.cbcpu, GFP_KERNEL)) |
924 | goto err_free_rcpumask_pcpu; | |
74781387 | 925 | |
bbefa1dd | 926 | INIT_LIST_HEAD(&pinst->pslist); |
16295bec | 927 | |
e15bacbe DK |
928 | cpumask_copy(pinst->cpumask.pcpu, pcpumask); |
929 | cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); | |
bbefa1dd HX |
930 | cpumask_and(pinst->rcpumask.pcpu, pcpumask, cpu_online_mask); |
931 | cpumask_and(pinst->rcpumask.cbcpu, cbcpumask, cpu_online_mask); | |
932 | ||
933 | if (padata_setup_cpumasks(pinst)) | |
91a71d61 | 934 | goto err_free_rcpumask_cbcpu; |
16295bec SK |
935 | |
936 | pinst->flags = 0; | |
937 | ||
5e017dc3 | 938 | kobject_init(&pinst->kobj, &padata_attr_type); |
16295bec SK |
939 | mutex_init(&pinst->lock); |
940 | ||
b8b4a416 | 941 | #ifdef CONFIG_HOTPLUG_CPU |
c5a81c8f | 942 | cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node); |
894c9ef9 DJ |
943 | cpuhp_state_add_instance_nocalls_cpuslocked(CPUHP_PADATA_DEAD, |
944 | &pinst->node); | |
b8b4a416 | 945 | #endif |
cc491d8e DJ |
946 | |
947 | put_online_cpus(); | |
948 | ||
16295bec SK |
949 | return pinst; |
950 | ||
bbefa1dd HX |
951 | err_free_rcpumask_cbcpu: |
952 | free_cpumask_var(pinst->rcpumask.cbcpu); | |
953 | err_free_rcpumask_pcpu: | |
954 | free_cpumask_var(pinst->rcpumask.pcpu); | |
e15bacbe DK |
955 | err_free_masks: |
956 | free_cpumask_var(pinst->cpumask.pcpu); | |
957 | free_cpumask_var(pinst->cpumask.cbcpu); | |
45d153c0 DJ |
958 | err_free_serial_wq: |
959 | destroy_workqueue(pinst->serial_wq); | |
cc491d8e DJ |
960 | err_put_cpus: |
961 | put_online_cpus(); | |
45d153c0 | 962 | destroy_workqueue(pinst->parallel_wq); |
16295bec SK |
963 | err_free_inst: |
964 | kfree(pinst); | |
965 | err: | |
966 | return NULL; | |
967 | } | |
16295bec | 968 | |
9596695e TG |
969 | /** |
970 | * padata_alloc_possible - Allocate and initialize padata instance. | |
971 | * Use the cpu_possible_mask for serial and | |
972 | * parallel workers. | |
973 | * | |
b128a304 | 974 | * @name: used to identify the instance |
bfcdcef8 DJ |
975 | * |
976 | * Return: new instance on success, NULL on error | |
9596695e | 977 | */ |
b128a304 | 978 | struct padata_instance *padata_alloc_possible(const char *name) |
9596695e | 979 | { |
b128a304 | 980 | return padata_alloc(name, cpu_possible_mask, cpu_possible_mask); |
9596695e TG |
981 | } |
982 | EXPORT_SYMBOL(padata_alloc_possible); | |
983 | ||
0198ffd1 | 984 | /** |
16295bec SK |
985 | * padata_free - free a padata instance |
986 | * | |
bfcdcef8 | 987 | * @pinst: padata instance to free |
16295bec SK |
988 | */ |
989 | void padata_free(struct padata_instance *pinst) | |
990 | { | |
5e017dc3 | 991 | kobject_put(&pinst->kobj); |
16295bec SK |
992 | } |
993 | EXPORT_SYMBOL(padata_free); | |
30e92153 | 994 | |
bbefa1dd HX |
995 | /** |
996 | * padata_alloc_shell - Allocate and initialize padata shell. | |
997 | * | |
998 | * @pinst: Parent padata_instance object. | |
bfcdcef8 DJ |
999 | * |
1000 | * Return: new shell on success, NULL on error | |
bbefa1dd HX |
1001 | */ |
1002 | struct padata_shell *padata_alloc_shell(struct padata_instance *pinst) | |
1003 | { | |
1004 | struct parallel_data *pd; | |
1005 | struct padata_shell *ps; | |
1006 | ||
1007 | ps = kzalloc(sizeof(*ps), GFP_KERNEL); | |
1008 | if (!ps) | |
1009 | goto out; | |
1010 | ||
1011 | ps->pinst = pinst; | |
1012 | ||
1013 | get_online_cpus(); | |
1014 | pd = padata_alloc_pd(ps); | |
1015 | put_online_cpus(); | |
1016 | ||
1017 | if (!pd) | |
1018 | goto out_free_ps; | |
1019 | ||
1020 | mutex_lock(&pinst->lock); | |
1021 | RCU_INIT_POINTER(ps->pd, pd); | |
1022 | list_add(&ps->list, &pinst->pslist); | |
1023 | mutex_unlock(&pinst->lock); | |
1024 | ||
1025 | return ps; | |
1026 | ||
1027 | out_free_ps: | |
1028 | kfree(ps); | |
1029 | out: | |
1030 | return NULL; | |
1031 | } | |
1032 | EXPORT_SYMBOL(padata_alloc_shell); | |
1033 | ||
1034 | /** | |
1035 | * padata_free_shell - free a padata shell | |
1036 | * | |
1037 | * @ps: padata shell to free | |
1038 | */ | |
1039 | void padata_free_shell(struct padata_shell *ps) | |
1040 | { | |
1041 | struct padata_instance *pinst = ps->pinst; | |
1042 | ||
1043 | mutex_lock(&pinst->lock); | |
1044 | list_del(&ps->list); | |
1045 | padata_free_pd(rcu_dereference_protected(ps->pd, 1)); | |
1046 | mutex_unlock(&pinst->lock); | |
1047 | ||
1048 | kfree(ps); | |
1049 | } | |
1050 | EXPORT_SYMBOL(padata_free_shell); | |
1051 | ||
30e92153 SAS |
1052 | #ifdef CONFIG_HOTPLUG_CPU |
1053 | ||
1054 | static __init int padata_driver_init(void) | |
1055 | { | |
1056 | int ret; | |
1057 | ||
1058 | ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "padata:online", | |
894c9ef9 | 1059 | padata_cpu_online, NULL); |
30e92153 SAS |
1060 | if (ret < 0) |
1061 | return ret; | |
1062 | hp_online = ret; | |
894c9ef9 DJ |
1063 | |
1064 | ret = cpuhp_setup_state_multi(CPUHP_PADATA_DEAD, "padata:dead", | |
1065 | NULL, padata_cpu_dead); | |
1066 | if (ret < 0) { | |
1067 | cpuhp_remove_multi_state(hp_online); | |
1068 | return ret; | |
1069 | } | |
30e92153 SAS |
1070 | return 0; |
1071 | } | |
1072 | module_init(padata_driver_init); | |
1073 | ||
1074 | static __exit void padata_driver_exit(void) | |
1075 | { | |
894c9ef9 | 1076 | cpuhp_remove_multi_state(CPUHP_PADATA_DEAD); |
30e92153 SAS |
1077 | cpuhp_remove_multi_state(hp_online); |
1078 | } | |
1079 | module_exit(padata_driver_exit); | |
1080 | #endif |