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Steffen Klassert16295be2010-01-06 19:47:10 +11001/*
2 * padata.c - generic interface to process data streams in parallel
3 *
Steffen Klassert107f8bd2012-03-28 08:42:34 +02004 * See Documentation/padata.txt for an api documentation.
5 *
Steffen Klassert16295be2010-01-06 19:47:10 +11006 * 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
Paul Gortmaker9984de12011-05-23 14:51:41 -040023#include <linux/export.h>
Steffen Klassert16295be2010-01-06 19:47:10 +110024#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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090030#include <linux/slab.h>
Dan Kruchinin5e017dc2010-07-14 14:33:08 +040031#include <linux/sysfs.h>
Steffen Klassert16295be2010-01-06 19:47:10 +110032#include <linux/rcupdate.h>
Sebastian Andrzej Siewior30e92152016-09-06 19:04:49 +020033#include <linux/module.h>
Steffen Klassert16295be2010-01-06 19:47:10 +110034
Steffen Klassert97e3d942010-04-29 14:37:32 +020035#define MAX_OBJ_NUM 1000
Steffen Klassert16295be2010-01-06 19:47:10 +110036
37static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
38{
39 int cpu, target_cpu;
40
Dan Kruchinine15bacb2010-07-14 14:31:57 +040041 target_cpu = cpumask_first(pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +110042 for (cpu = 0; cpu < cpu_index; cpu++)
Dan Kruchinine15bacb2010-07-14 14:31:57 +040043 target_cpu = cpumask_next(target_cpu, pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +110044
45 return target_cpu;
46}
47
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +010048static int padata_cpu_hash(struct parallel_data *pd)
Steffen Klassert16295be2010-01-06 19:47:10 +110049{
Mathias Krause0b6b0982013-10-25 12:14:15 +020050 unsigned int seq_nr;
Steffen Klassert16295be2010-01-06 19:47:10 +110051 int cpu_index;
Steffen Klassert16295be2010-01-06 19:47:10 +110052
53 /*
54 * Hash the sequence numbers to the cpus by taking
55 * seq_nr mod. number of cpus in use.
56 */
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +010057
Mathias Krause0b6b0982013-10-25 12:14:15 +020058 seq_nr = atomic_inc_return(&pd->seq_nr);
59 cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +110060
61 return padata_index_to_cpu(pd, cpu_index);
62}
63
Dan Kruchinine15bacb2010-07-14 14:31:57 +040064static void padata_parallel_worker(struct work_struct *parallel_work)
Steffen Klassert16295be2010-01-06 19:47:10 +110065{
Dan Kruchinine15bacb2010-07-14 14:31:57 +040066 struct padata_parallel_queue *pqueue;
Steffen Klassert16295be2010-01-06 19:47:10 +110067 LIST_HEAD(local_list);
68
69 local_bh_disable();
Dan Kruchinine15bacb2010-07-14 14:31:57 +040070 pqueue = container_of(parallel_work,
71 struct padata_parallel_queue, work);
Steffen Klassert16295be2010-01-06 19:47:10 +110072
Dan Kruchinine15bacb2010-07-14 14:31:57 +040073 spin_lock(&pqueue->parallel.lock);
74 list_replace_init(&pqueue->parallel.list, &local_list);
75 spin_unlock(&pqueue->parallel.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +110076
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
Steffen Klassert0198ffd2010-05-19 13:44:27 +100091/**
Steffen Klassert16295be2010-01-06 19:47:10 +110092 * 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,
Dan Kruchinine15bacb2010-07-14 14:31:57 +040097 * must be in the serial cpumask of padata(i.e. cpumask.cbcpu).
Steffen Klassert16295be2010-01-06 19:47:10 +110098 *
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 */
103int padata_do_parallel(struct padata_instance *pinst,
104 struct padata_priv *padata, int cb_cpu)
105{
106 int target_cpu, err;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400107 struct padata_parallel_queue *queue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100108 struct parallel_data *pd;
109
110 rcu_read_lock_bh();
111
Mathias Krausec0e656b2013-11-28 19:20:05 +0100112 pd = rcu_dereference_bh(pinst->pd);
Steffen Klassert16295be2010-01-06 19:47:10 +1100113
Steffen Klassert83f619f2010-07-07 15:32:02 +0200114 err = -EINVAL;
Steffen Klassert74247132010-07-20 08:51:25 +0200115 if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID)
Steffen Klassert16295be2010-01-06 19:47:10 +1100116 goto out;
117
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400118 if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu))
Steffen Klassert16295be2010-01-06 19:47:10 +1100119 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
Steffen Klassert83f619f2010-07-07 15:32:02 +0200128 err = 0;
Steffen Klassert16295be2010-01-06 19:47:10 +1100129 atomic_inc(&pd->refcnt);
130 padata->pd = pd;
131 padata->cb_cpu = cb_cpu;
132
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100133 target_cpu = padata_cpu_hash(pd);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400134 queue = per_cpu_ptr(pd->pqueue, target_cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100135
136 spin_lock(&queue->parallel.lock);
137 list_add_tail(&padata->list, &queue->parallel.list);
138 spin_unlock(&queue->parallel.lock);
139
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400140 queue_work_on(target_cpu, pinst->wq, &queue->work);
Steffen Klassert16295be2010-01-06 19:47:10 +1100141
142out:
143 rcu_read_unlock_bh();
144
145 return err;
146}
147EXPORT_SYMBOL(padata_do_parallel);
148
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000149/*
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 *
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000157 * -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 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100164static struct padata_priv *padata_get_next(struct parallel_data *pd)
165{
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200166 int cpu, num_cpus;
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100167 unsigned int next_nr, next_index;
Shan Weif0fcf202012-12-06 17:16:23 +0800168 struct padata_parallel_queue *next_queue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100169 struct padata_priv *padata;
170 struct padata_list *reorder;
171
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400172 num_cpus = cpumask_weight(pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100173
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200174 /*
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);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400181 next_queue = per_cpu_ptr(pd->pqueue, cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100182
Steffen Klassert16295be2010-01-06 19:47:10 +1100183 reorder = &next_queue->reorder;
184
Jason A. Donenfeldde5540d2017-03-23 12:24:43 +0100185 spin_lock(&reorder->lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100186 if (!list_empty(&reorder->list)) {
187 padata = list_entry(reorder->list.next,
188 struct padata_priv, list);
189
Steffen Klassert16295be2010-01-06 19:47:10 +1100190 list_del_init(&padata->list);
191 atomic_dec(&pd->reorder_objects);
Steffen Klassert16295be2010-01-06 19:47:10 +1100192
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200193 pd->processed++;
Steffen Klassert16295be2010-01-06 19:47:10 +1100194
Jason A. Donenfeldde5540d2017-03-23 12:24:43 +0100195 spin_unlock(&reorder->lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100196 goto out;
197 }
Jason A. Donenfeldde5540d2017-03-23 12:24:43 +0100198 spin_unlock(&reorder->lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100199
Shan Weif0fcf202012-12-06 17:16:23 +0800200 if (__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index) {
Steffen Klassert16295be2010-01-06 19:47:10 +1100201 padata = ERR_PTR(-ENODATA);
202 goto out;
203 }
204
205 padata = ERR_PTR(-EINPROGRESS);
206out:
207 return padata;
208}
209
210static void padata_reorder(struct parallel_data *pd)
211{
Steffen Klassert30478172012-03-09 07:20:12 +0100212 int cb_cpu;
Steffen Klassert16295be2010-01-06 19:47:10 +1100213 struct padata_priv *padata;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400214 struct padata_serial_queue *squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100215 struct padata_instance *pinst = pd->pinst;
216
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000217 /*
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 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100227 if (!spin_trylock_bh(&pd->lock))
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000228 return;
Steffen Klassert16295be2010-01-06 19:47:10 +1100229
230 while (1) {
231 padata = padata_get_next(pd);
232
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000233 /*
Jason A. Donenfeld69b34842017-04-12 10:40:19 +0200234 * 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.
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000237 */
Jason A. Donenfeld69b34842017-04-12 10:40:19 +0200238 if (PTR_ERR(padata) == -EINPROGRESS)
Steffen Klassert16295be2010-01-06 19:47:10 +1100239 break;
240
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000241 /*
242 * This cpu has to do the parallel processing of the next
243 * object. It's waiting in the cpu's parallelization queue,
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300244 * so exit immediately.
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000245 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100246 if (PTR_ERR(padata) == -ENODATA) {
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000247 del_timer(&pd->timer);
Steffen Klassert16295be2010-01-06 19:47:10 +1100248 spin_unlock_bh(&pd->lock);
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000249 return;
Steffen Klassert16295be2010-01-06 19:47:10 +1100250 }
251
Steffen Klassert30478172012-03-09 07:20:12 +0100252 cb_cpu = padata->cb_cpu;
253 squeue = per_cpu_ptr(pd->squeue, cb_cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100254
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400255 spin_lock(&squeue->serial.lock);
256 list_add_tail(&padata->list, &squeue->serial.list);
257 spin_unlock(&squeue->serial.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100258
Steffen Klassert30478172012-03-09 07:20:12 +0100259 queue_work_on(cb_cpu, pinst->wq, &squeue->work);
Steffen Klassert16295be2010-01-06 19:47:10 +1100260 }
261
262 spin_unlock_bh(&pd->lock);
263
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000264 /*
265 * The next object that needs serialization might have arrived to
266 * the reorder queues in the meantime, we will be called again
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300267 * from the timer function if no one else cares for it.
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000268 */
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000269 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);
Steffen Klassert16295be2010-01-06 19:47:10 +1100274
Steffen Klassert16295be2010-01-06 19:47:10 +1100275 return;
276}
277
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000278static void padata_reorder_timer(unsigned long arg)
279{
280 struct parallel_data *pd = (struct parallel_data *)arg;
281
282 padata_reorder(pd);
283}
284
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400285static void padata_serial_worker(struct work_struct *serial_work)
Steffen Klassert16295be2010-01-06 19:47:10 +1100286{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400287 struct padata_serial_queue *squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100288 struct parallel_data *pd;
289 LIST_HEAD(local_list);
290
291 local_bh_disable();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400292 squeue = container_of(serial_work, struct padata_serial_queue, work);
293 pd = squeue->pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100294
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400295 spin_lock(&squeue->serial.lock);
296 list_replace_init(&squeue->serial.list, &local_list);
297 spin_unlock(&squeue->serial.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100298
299 while (!list_empty(&local_list)) {
300 struct padata_priv *padata;
301
302 padata = list_entry(local_list.next,
303 struct padata_priv, list);
304
305 list_del_init(&padata->list);
306
307 padata->serial(padata);
308 atomic_dec(&pd->refcnt);
309 }
310 local_bh_enable();
311}
312
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000313/**
Steffen Klassert16295be2010-01-06 19:47:10 +1100314 * padata_do_serial - padata serialization function
315 *
316 * @padata: object to be serialized.
317 *
318 * padata_do_serial must be called for every parallelized object.
319 * The serialization callback function will run with BHs off.
320 */
321void padata_do_serial(struct padata_priv *padata)
322{
323 int cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400324 struct padata_parallel_queue *pqueue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100325 struct parallel_data *pd;
326
327 pd = padata->pd;
328
329 cpu = get_cpu();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400330 pqueue = per_cpu_ptr(pd->pqueue, cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100331
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400332 spin_lock(&pqueue->reorder.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100333 atomic_inc(&pd->reorder_objects);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400334 list_add_tail(&padata->list, &pqueue->reorder.list);
335 spin_unlock(&pqueue->reorder.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100336
337 put_cpu();
338
339 padata_reorder(pd);
340}
341EXPORT_SYMBOL(padata_do_serial);
342
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400343static int padata_setup_cpumasks(struct parallel_data *pd,
344 const struct cpumask *pcpumask,
345 const struct cpumask *cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100346{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400347 if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL))
348 return -ENOMEM;
349
Steffen Klassert13614e02012-03-28 08:43:21 +0200350 cpumask_and(pd->cpumask.pcpu, pcpumask, cpu_online_mask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400351 if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) {
Jason A. Donenfeld07a77922017-04-07 02:33:30 +0200352 free_cpumask_var(pd->cpumask.pcpu);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400353 return -ENOMEM;
354 }
355
Steffen Klassert13614e02012-03-28 08:43:21 +0200356 cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_online_mask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400357 return 0;
358}
359
360static void __padata_list_init(struct padata_list *pd_list)
361{
362 INIT_LIST_HEAD(&pd_list->list);
363 spin_lock_init(&pd_list->lock);
364}
365
366/* Initialize all percpu queues used by serial workers */
367static void padata_init_squeues(struct parallel_data *pd)
368{
369 int cpu;
370 struct padata_serial_queue *squeue;
371
372 for_each_cpu(cpu, pd->cpumask.cbcpu) {
373 squeue = per_cpu_ptr(pd->squeue, cpu);
374 squeue->pd = pd;
375 __padata_list_init(&squeue->serial);
376 INIT_WORK(&squeue->work, padata_serial_worker);
377 }
378}
379
380/* Initialize all percpu queues used by parallel workers */
381static void padata_init_pqueues(struct parallel_data *pd)
382{
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100383 int cpu_index, cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400384 struct padata_parallel_queue *pqueue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100385
386 cpu_index = 0;
Mathias Krause1bd845b2017-09-08 20:57:09 +0200387 for_each_possible_cpu(cpu) {
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400388 pqueue = per_cpu_ptr(pd->pqueue, cpu);
Mathias Krause1bd845b2017-09-08 20:57:09 +0200389
390 if (!cpumask_test_cpu(cpu, pd->cpumask.pcpu)) {
391 pqueue->cpu_index = -1;
392 continue;
393 }
394
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400395 pqueue->pd = pd;
396 pqueue->cpu_index = cpu_index;
Steffen Klassertfad3a902010-07-20 08:48:34 +0200397 cpu_index++;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400398
399 __padata_list_init(&pqueue->reorder);
400 __padata_list_init(&pqueue->parallel);
401 INIT_WORK(&pqueue->work, padata_parallel_worker);
402 atomic_set(&pqueue->num_obj, 0);
403 }
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400404}
405
406/* Allocate and initialize the internal cpumask dependend resources. */
407static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
408 const struct cpumask *pcpumask,
409 const struct cpumask *cbcpumask)
410{
411 struct parallel_data *pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100412
413 pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL);
414 if (!pd)
415 goto err;
416
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400417 pd->pqueue = alloc_percpu(struct padata_parallel_queue);
418 if (!pd->pqueue)
Steffen Klassert16295be2010-01-06 19:47:10 +1100419 goto err_free_pd;
420
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400421 pd->squeue = alloc_percpu(struct padata_serial_queue);
422 if (!pd->squeue)
423 goto err_free_pqueue;
424 if (padata_setup_cpumasks(pd, pcpumask, cbcpumask) < 0)
425 goto err_free_squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100426
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400427 padata_init_pqueues(pd);
428 padata_init_squeues(pd);
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000429 setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd);
Mathias Krause0b6b0982013-10-25 12:14:15 +0200430 atomic_set(&pd->seq_nr, -1);
Steffen Klassert16295be2010-01-06 19:47:10 +1100431 atomic_set(&pd->reorder_objects, 0);
432 atomic_set(&pd->refcnt, 0);
433 pd->pinst = pinst;
434 spin_lock_init(&pd->lock);
435
436 return pd;
437
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400438err_free_squeue:
439 free_percpu(pd->squeue);
440err_free_pqueue:
441 free_percpu(pd->pqueue);
Steffen Klassert16295be2010-01-06 19:47:10 +1100442err_free_pd:
443 kfree(pd);
444err:
445 return NULL;
446}
447
448static void padata_free_pd(struct parallel_data *pd)
449{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400450 free_cpumask_var(pd->cpumask.pcpu);
451 free_cpumask_var(pd->cpumask.cbcpu);
452 free_percpu(pd->pqueue);
453 free_percpu(pd->squeue);
Steffen Klassert16295be2010-01-06 19:47:10 +1100454 kfree(pd);
455}
456
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000457/* Flush all objects out of the padata queues. */
Steffen Klassert2b73b072010-05-19 13:43:46 +1000458static void padata_flush_queues(struct parallel_data *pd)
459{
460 int cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400461 struct padata_parallel_queue *pqueue;
462 struct padata_serial_queue *squeue;
Steffen Klassert2b73b072010-05-19 13:43:46 +1000463
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400464 for_each_cpu(cpu, pd->cpumask.pcpu) {
465 pqueue = per_cpu_ptr(pd->pqueue, cpu);
466 flush_work(&pqueue->work);
Steffen Klassert2b73b072010-05-19 13:43:46 +1000467 }
468
469 del_timer_sync(&pd->timer);
470
471 if (atomic_read(&pd->reorder_objects))
472 padata_reorder(pd);
473
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400474 for_each_cpu(cpu, pd->cpumask.cbcpu) {
475 squeue = per_cpu_ptr(pd->squeue, cpu);
476 flush_work(&squeue->work);
Steffen Klassert2b73b072010-05-19 13:43:46 +1000477 }
478
479 BUG_ON(atomic_read(&pd->refcnt) != 0);
480}
481
Steffen Klassert4c879172010-07-07 15:30:10 +0200482static void __padata_start(struct padata_instance *pinst)
483{
484 pinst->flags |= PADATA_INIT;
485}
486
Steffen Klassertee836552010-07-07 15:30:47 +0200487static 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();
495
496 get_online_cpus();
497 padata_flush_queues(pinst->pd);
498 put_online_cpus();
499}
500
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300501/* Replace the internal control structure with a new one. */
Steffen Klassert16295be2010-01-06 19:47:10 +1100502static void padata_replace(struct padata_instance *pinst,
503 struct parallel_data *pd_new)
504{
505 struct parallel_data *pd_old = pinst->pd;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400506 int notification_mask = 0;
Steffen Klassert16295be2010-01-06 19:47:10 +1100507
508 pinst->flags |= PADATA_RESET;
509
510 rcu_assign_pointer(pinst->pd, pd_new);
511
512 synchronize_rcu();
513
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400514 if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu))
515 notification_mask |= PADATA_CPU_PARALLEL;
516 if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu))
517 notification_mask |= PADATA_CPU_SERIAL;
Steffen Klassert16295be2010-01-06 19:47:10 +1100518
Steffen Klassert16295be2010-01-06 19:47:10 +1100519 padata_flush_queues(pd_old);
520 padata_free_pd(pd_old);
521
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400522 if (notification_mask)
523 blocking_notifier_call_chain(&pinst->cpumask_change_notifier,
Steffen Klassertc6356962010-07-27 07:15:50 +0200524 notification_mask,
525 &pd_new->cpumask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400526
Steffen Klassert16295be2010-01-06 19:47:10 +1100527 pinst->flags &= ~PADATA_RESET;
528}
529
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000530/**
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400531 * padata_register_cpumask_notifier - Registers a notifier that will be called
532 * if either pcpu or cbcpu or both cpumasks change.
Steffen Klassert16295be2010-01-06 19:47:10 +1100533 *
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400534 * @pinst: A poineter to padata instance
535 * @nblock: A pointer to notifier block.
Steffen Klassert16295be2010-01-06 19:47:10 +1100536 */
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400537int padata_register_cpumask_notifier(struct padata_instance *pinst,
538 struct notifier_block *nblock)
Steffen Klassert16295be2010-01-06 19:47:10 +1100539{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400540 return blocking_notifier_chain_register(&pinst->cpumask_change_notifier,
541 nblock);
542}
543EXPORT_SYMBOL(padata_register_cpumask_notifier);
Steffen Klassert16295be2010-01-06 19:47:10 +1100544
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400545/**
546 * padata_unregister_cpumask_notifier - Unregisters cpumask notifier
547 * registered earlier using padata_register_cpumask_notifier
548 *
549 * @pinst: A pointer to data instance.
550 * @nlock: A pointer to notifier block.
551 */
552int padata_unregister_cpumask_notifier(struct padata_instance *pinst,
553 struct notifier_block *nblock)
554{
555 return blocking_notifier_chain_unregister(
556 &pinst->cpumask_change_notifier,
557 nblock);
558}
559EXPORT_SYMBOL(padata_unregister_cpumask_notifier);
Steffen Klassert16295be2010-01-06 19:47:10 +1100560
Steffen Klassert6751fb32010-04-29 14:42:30 +0200561
Steffen Klassert33e54452010-07-07 15:31:26 +0200562/* If cpumask contains no active cpu, we mark the instance as invalid. */
563static bool padata_validate_cpumask(struct padata_instance *pinst,
564 const struct cpumask *cpumask)
565{
Steffen Klassert13614e02012-03-28 08:43:21 +0200566 if (!cpumask_intersects(cpumask, cpu_online_mask)) {
Steffen Klassert33e54452010-07-07 15:31:26 +0200567 pinst->flags |= PADATA_INVALID;
568 return false;
Steffen Klassert16295be2010-01-06 19:47:10 +1100569 }
570
Steffen Klassert33e54452010-07-07 15:31:26 +0200571 pinst->flags &= ~PADATA_INVALID;
572 return true;
573}
574
Steffen Klassert65ff5772010-07-27 07:15:06 +0200575static int __padata_set_cpumasks(struct padata_instance *pinst,
576 cpumask_var_t pcpumask,
577 cpumask_var_t cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100578{
Steffen Klassert33e54452010-07-07 15:31:26 +0200579 int valid;
Steffen Klassert65ff5772010-07-27 07:15:06 +0200580 struct parallel_data *pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100581
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400582 valid = padata_validate_cpumask(pinst, pcpumask);
583 if (!valid) {
584 __padata_stop(pinst);
585 goto out_replace;
586 }
587
588 valid = padata_validate_cpumask(pinst, cbcpumask);
Steffen Klassertb89661d2010-07-20 08:49:20 +0200589 if (!valid)
Steffen Klassert33e54452010-07-07 15:31:26 +0200590 __padata_stop(pinst);
Steffen Klassert33e54452010-07-07 15:31:26 +0200591
Steffen Klassertb89661d2010-07-20 08:49:20 +0200592out_replace:
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400593 pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
Steffen Klassert65ff5772010-07-27 07:15:06 +0200594 if (!pd)
595 return -ENOMEM;
Steffen Klassert16295be2010-01-06 19:47:10 +1100596
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400597 cpumask_copy(pinst->cpumask.pcpu, pcpumask);
598 cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
Steffen Klassert16295be2010-01-06 19:47:10 +1100599
600 padata_replace(pinst, pd);
601
Steffen Klassert33e54452010-07-07 15:31:26 +0200602 if (valid)
603 __padata_start(pinst);
604
Steffen Klassert65ff5772010-07-27 07:15:06 +0200605 return 0;
606}
607
608/**
Steffen Klassert65ff5772010-07-27 07:15:06 +0200609 * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value
610 * equivalent to @cpumask.
611 *
612 * @pinst: padata instance
613 * @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding
614 * to parallel and serial cpumasks respectively.
615 * @cpumask: the cpumask to use
616 */
617int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
618 cpumask_var_t cpumask)
619{
620 struct cpumask *serial_mask, *parallel_mask;
621 int err = -EINVAL;
622
623 mutex_lock(&pinst->lock);
624 get_online_cpus();
625
626 switch (cpumask_type) {
627 case PADATA_CPU_PARALLEL:
628 serial_mask = pinst->cpumask.cbcpu;
629 parallel_mask = cpumask;
630 break;
631 case PADATA_CPU_SERIAL:
632 parallel_mask = pinst->cpumask.pcpu;
633 serial_mask = cpumask;
634 break;
635 default:
636 goto out;
637 }
638
639 err = __padata_set_cpumasks(pinst, parallel_mask, serial_mask);
640
Steffen Klassert16295be2010-01-06 19:47:10 +1100641out:
Steffen Klassert6751fb32010-04-29 14:42:30 +0200642 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100643 mutex_unlock(&pinst->lock);
644
645 return err;
646}
647EXPORT_SYMBOL(padata_set_cpumask);
648
Arnd Bergmann19d795b2016-05-19 17:09:59 -0700649/**
650 * padata_start - start the parallel processing
651 *
652 * @pinst: padata instance to start
653 */
654int padata_start(struct padata_instance *pinst)
655{
656 int err = 0;
657
658 mutex_lock(&pinst->lock);
659
660 if (pinst->flags & PADATA_INVALID)
661 err = -EINVAL;
662
663 __padata_start(pinst);
664
665 mutex_unlock(&pinst->lock);
666
667 return err;
668}
669EXPORT_SYMBOL(padata_start);
670
671/**
672 * padata_stop - stop the parallel processing
673 *
674 * @pinst: padata instance to stop
675 */
676void padata_stop(struct padata_instance *pinst)
677{
678 mutex_lock(&pinst->lock);
679 __padata_stop(pinst);
680 mutex_unlock(&pinst->lock);
681}
682EXPORT_SYMBOL(padata_stop);
683
684#ifdef CONFIG_HOTPLUG_CPU
685
Steffen Klassert16295be2010-01-06 19:47:10 +1100686static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
687{
688 struct parallel_data *pd;
689
Steffen Klassert13614e02012-03-28 08:43:21 +0200690 if (cpumask_test_cpu(cpu, cpu_online_mask)) {
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400691 pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
692 pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100693 if (!pd)
694 return -ENOMEM;
695
696 padata_replace(pinst, pd);
Steffen Klassert33e54452010-07-07 15:31:26 +0200697
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400698 if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) &&
699 padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
Steffen Klassert33e54452010-07-07 15:31:26 +0200700 __padata_start(pinst);
Steffen Klassert16295be2010-01-06 19:47:10 +1100701 }
702
703 return 0;
704}
705
Steffen Klassert16295be2010-01-06 19:47:10 +1100706static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
707{
Steffen Klassert33e54452010-07-07 15:31:26 +0200708 struct parallel_data *pd = NULL;
Steffen Klassert16295be2010-01-06 19:47:10 +1100709
710 if (cpumask_test_cpu(cpu, cpu_online_mask)) {
Steffen Klassert33e54452010-07-07 15:31:26 +0200711
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400712 if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) ||
Steffen Klassertb89661d2010-07-20 08:49:20 +0200713 !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
Steffen Klassert33e54452010-07-07 15:31:26 +0200714 __padata_stop(pinst);
Steffen Klassert33e54452010-07-07 15:31:26 +0200715
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400716 pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
717 pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100718 if (!pd)
719 return -ENOMEM;
720
721 padata_replace(pinst, pd);
Steffen Klassert96120902012-03-28 08:44:07 +0200722
723 cpumask_clear_cpu(cpu, pd->cpumask.cbcpu);
724 cpumask_clear_cpu(cpu, pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100725 }
726
727 return 0;
728}
729
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400730 /**
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300731 * padata_remove_cpu - remove a cpu from the one or both(serial and parallel)
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400732 * padata cpumasks.
Steffen Klassert16295be2010-01-06 19:47:10 +1100733 *
734 * @pinst: padata instance
735 * @cpu: cpu to remove
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400736 * @mask: bitmask specifying from which cpumask @cpu should be removed
737 * The @mask may be any combination of the following flags:
738 * PADATA_CPU_SERIAL - serial cpumask
739 * PADATA_CPU_PARALLEL - parallel cpumask
Steffen Klassert16295be2010-01-06 19:47:10 +1100740 */
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400741int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100742{
743 int err;
744
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400745 if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL)))
746 return -EINVAL;
747
Steffen Klassert16295be2010-01-06 19:47:10 +1100748 mutex_lock(&pinst->lock);
749
Steffen Klassert6751fb32010-04-29 14:42:30 +0200750 get_online_cpus();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400751 if (mask & PADATA_CPU_SERIAL)
752 cpumask_clear_cpu(cpu, pinst->cpumask.cbcpu);
753 if (mask & PADATA_CPU_PARALLEL)
754 cpumask_clear_cpu(cpu, pinst->cpumask.pcpu);
755
Steffen Klassert16295be2010-01-06 19:47:10 +1100756 err = __padata_remove_cpu(pinst, cpu);
Steffen Klassert6751fb32010-04-29 14:42:30 +0200757 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100758
759 mutex_unlock(&pinst->lock);
760
761 return err;
762}
763EXPORT_SYMBOL(padata_remove_cpu);
764
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400765static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu)
766{
767 return cpumask_test_cpu(cpu, pinst->cpumask.pcpu) ||
768 cpumask_test_cpu(cpu, pinst->cpumask.cbcpu);
769}
770
Sebastian Andrzej Siewior30e92152016-09-06 19:04:49 +0200771static int padata_cpu_online(unsigned int cpu, struct hlist_node *node)
Steffen Klassert16295be2010-01-06 19:47:10 +1100772{
Steffen Klassert16295be2010-01-06 19:47:10 +1100773 struct padata_instance *pinst;
Sebastian Andrzej Siewior30e92152016-09-06 19:04:49 +0200774 int ret;
Steffen Klassert16295be2010-01-06 19:47:10 +1100775
Sebastian Andrzej Siewior30e92152016-09-06 19:04:49 +0200776 pinst = hlist_entry_safe(node, struct padata_instance, node);
777 if (!pinst_has_cpu(pinst, cpu))
778 return 0;
Steffen Klassert16295be2010-01-06 19:47:10 +1100779
Sebastian Andrzej Siewior30e92152016-09-06 19:04:49 +0200780 mutex_lock(&pinst->lock);
781 ret = __padata_add_cpu(pinst, cpu);
782 mutex_unlock(&pinst->lock);
783 return ret;
Steffen Klassert16295be2010-01-06 19:47:10 +1100784}
Sebastian Andrzej Siewior30e92152016-09-06 19:04:49 +0200785
786static int padata_cpu_prep_down(unsigned int cpu, struct hlist_node *node)
787{
788 struct padata_instance *pinst;
789 int ret;
790
791 pinst = hlist_entry_safe(node, struct padata_instance, node);
792 if (!pinst_has_cpu(pinst, cpu))
793 return 0;
794
795 mutex_lock(&pinst->lock);
796 ret = __padata_remove_cpu(pinst, cpu);
797 mutex_unlock(&pinst->lock);
798 return ret;
799}
800
801static enum cpuhp_state hp_online;
Steffen Klasserte2cb2f12010-04-29 14:40:10 +0200802#endif
Steffen Klassert16295be2010-01-06 19:47:10 +1100803
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400804static void __padata_free(struct padata_instance *pinst)
805{
806#ifdef CONFIG_HOTPLUG_CPU
Sebastian Andrzej Siewior30e92152016-09-06 19:04:49 +0200807 cpuhp_state_remove_instance_nocalls(hp_online, &pinst->node);
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400808#endif
809
810 padata_stop(pinst);
811 padata_free_pd(pinst->pd);
812 free_cpumask_var(pinst->cpumask.pcpu);
813 free_cpumask_var(pinst->cpumask.cbcpu);
814 kfree(pinst);
815}
816
817#define kobj2pinst(_kobj) \
818 container_of(_kobj, struct padata_instance, kobj)
819#define attr2pentry(_attr) \
820 container_of(_attr, struct padata_sysfs_entry, attr)
821
822static void padata_sysfs_release(struct kobject *kobj)
823{
824 struct padata_instance *pinst = kobj2pinst(kobj);
825 __padata_free(pinst);
826}
827
828struct padata_sysfs_entry {
829 struct attribute attr;
830 ssize_t (*show)(struct padata_instance *, struct attribute *, char *);
831 ssize_t (*store)(struct padata_instance *, struct attribute *,
832 const char *, size_t);
833};
834
835static ssize_t show_cpumask(struct padata_instance *pinst,
836 struct attribute *attr, char *buf)
837{
838 struct cpumask *cpumask;
839 ssize_t len;
840
841 mutex_lock(&pinst->lock);
842 if (!strcmp(attr->name, "serial_cpumask"))
843 cpumask = pinst->cpumask.cbcpu;
844 else
845 cpumask = pinst->cpumask.pcpu;
846
Tejun Heo4497da62015-02-13 14:38:05 -0800847 len = snprintf(buf, PAGE_SIZE, "%*pb\n",
848 nr_cpu_ids, cpumask_bits(cpumask));
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400849 mutex_unlock(&pinst->lock);
Tejun Heo4497da62015-02-13 14:38:05 -0800850 return len < PAGE_SIZE ? len : -EINVAL;
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400851}
852
853static ssize_t store_cpumask(struct padata_instance *pinst,
854 struct attribute *attr,
855 const char *buf, size_t count)
856{
857 cpumask_var_t new_cpumask;
858 ssize_t ret;
859 int mask_type;
860
861 if (!alloc_cpumask_var(&new_cpumask, GFP_KERNEL))
862 return -ENOMEM;
863
864 ret = bitmap_parse(buf, count, cpumask_bits(new_cpumask),
865 nr_cpumask_bits);
866 if (ret < 0)
867 goto out;
868
869 mask_type = !strcmp(attr->name, "serial_cpumask") ?
870 PADATA_CPU_SERIAL : PADATA_CPU_PARALLEL;
871 ret = padata_set_cpumask(pinst, mask_type, new_cpumask);
872 if (!ret)
873 ret = count;
874
875out:
876 free_cpumask_var(new_cpumask);
877 return ret;
878}
879
880#define PADATA_ATTR_RW(_name, _show_name, _store_name) \
881 static struct padata_sysfs_entry _name##_attr = \
882 __ATTR(_name, 0644, _show_name, _store_name)
883#define PADATA_ATTR_RO(_name, _show_name) \
884 static struct padata_sysfs_entry _name##_attr = \
885 __ATTR(_name, 0400, _show_name, NULL)
886
887PADATA_ATTR_RW(serial_cpumask, show_cpumask, store_cpumask);
888PADATA_ATTR_RW(parallel_cpumask, show_cpumask, store_cpumask);
889
890/*
891 * Padata sysfs provides the following objects:
892 * serial_cpumask [RW] - cpumask for serial workers
893 * parallel_cpumask [RW] - cpumask for parallel workers
Steffen Klassert16295be2010-01-06 19:47:10 +1100894 */
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400895static struct attribute *padata_default_attrs[] = {
896 &serial_cpumask_attr.attr,
897 &parallel_cpumask_attr.attr,
898 NULL,
899};
900
901static ssize_t padata_sysfs_show(struct kobject *kobj,
902 struct attribute *attr, char *buf)
Steffen Klassert16295be2010-01-06 19:47:10 +1100903{
Steffen Klassert16295be2010-01-06 19:47:10 +1100904 struct padata_instance *pinst;
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400905 struct padata_sysfs_entry *pentry;
906 ssize_t ret = -EIO;
907
908 pinst = kobj2pinst(kobj);
909 pentry = attr2pentry(attr);
910 if (pentry->show)
911 ret = pentry->show(pinst, attr, buf);
912
913 return ret;
914}
915
916static ssize_t padata_sysfs_store(struct kobject *kobj, struct attribute *attr,
917 const char *buf, size_t count)
918{
919 struct padata_instance *pinst;
920 struct padata_sysfs_entry *pentry;
921 ssize_t ret = -EIO;
922
923 pinst = kobj2pinst(kobj);
924 pentry = attr2pentry(attr);
925 if (pentry->show)
926 ret = pentry->store(pinst, attr, buf, count);
927
928 return ret;
929}
930
931static const struct sysfs_ops padata_sysfs_ops = {
932 .show = padata_sysfs_show,
933 .store = padata_sysfs_store,
934};
935
936static struct kobj_type padata_attr_type = {
937 .sysfs_ops = &padata_sysfs_ops,
938 .default_attrs = padata_default_attrs,
939 .release = padata_sysfs_release,
940};
941
Steffen Klassert16295be2010-01-06 19:47:10 +1100942/**
Steffen Klasserte6cc1172010-07-27 07:14:28 +0200943 * padata_alloc - allocate and initialize a padata instance and specify
944 * cpumasks for serial and parallel workers.
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400945 *
946 * @wq: workqueue to use for the allocated padata instance
947 * @pcpumask: cpumask that will be used for padata parallelization
948 * @cbcpumask: cpumask that will be used for padata serialization
Sebastian Andrzej Siewiorc5a81c82017-05-24 10:15:18 +0200949 *
950 * Must be called from a cpus_read_lock() protected region
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400951 */
Thomas Gleixner95966952017-05-24 10:15:17 +0200952static struct padata_instance *padata_alloc(struct workqueue_struct *wq,
953 const struct cpumask *pcpumask,
954 const struct cpumask *cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100955{
956 struct padata_instance *pinst;
Steffen Klassert33e54452010-07-07 15:31:26 +0200957 struct parallel_data *pd = NULL;
Steffen Klassert16295be2010-01-06 19:47:10 +1100958
959 pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL);
960 if (!pinst)
961 goto err;
962
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400963 if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL))
Steffen Klassert16295be2010-01-06 19:47:10 +1100964 goto err_free_inst;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400965 if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) {
966 free_cpumask_var(pinst->cpumask.pcpu);
967 goto err_free_inst;
Steffen Klassert33e54452010-07-07 15:31:26 +0200968 }
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400969 if (!padata_validate_cpumask(pinst, pcpumask) ||
970 !padata_validate_cpumask(pinst, cbcpumask))
971 goto err_free_masks;
Steffen Klassert16295be2010-01-06 19:47:10 +1100972
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400973 pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
974 if (!pd)
975 goto err_free_masks;
Steffen Klassert74781382010-03-04 13:30:22 +0800976
Steffen Klassert16295be2010-01-06 19:47:10 +1100977 rcu_assign_pointer(pinst->pd, pd);
978
979 pinst->wq = wq;
980
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400981 cpumask_copy(pinst->cpumask.pcpu, pcpumask);
982 cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
Steffen Klassert16295be2010-01-06 19:47:10 +1100983
984 pinst->flags = 0;
985
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400986 BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier);
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400987 kobject_init(&pinst->kobj, &padata_attr_type);
Steffen Klassert16295be2010-01-06 19:47:10 +1100988 mutex_init(&pinst->lock);
989
Richard Weinbergerb8b4a412013-08-23 13:12:33 +0200990#ifdef CONFIG_HOTPLUG_CPU
Sebastian Andrzej Siewiorc5a81c82017-05-24 10:15:18 +0200991 cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node);
Richard Weinbergerb8b4a412013-08-23 13:12:33 +0200992#endif
Steffen Klassert16295be2010-01-06 19:47:10 +1100993 return pinst;
994
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400995err_free_masks:
996 free_cpumask_var(pinst->cpumask.pcpu);
997 free_cpumask_var(pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100998err_free_inst:
999 kfree(pinst);
1000err:
1001 return NULL;
1002}
Steffen Klassert16295be2010-01-06 19:47:10 +11001003
Steffen Klassert0198ffd2010-05-19 13:44:27 +10001004/**
Thomas Gleixner95966952017-05-24 10:15:17 +02001005 * padata_alloc_possible - Allocate and initialize padata instance.
1006 * Use the cpu_possible_mask for serial and
1007 * parallel workers.
1008 *
1009 * @wq: workqueue to use for the allocated padata instance
Sebastian Andrzej Siewiorc5a81c82017-05-24 10:15:18 +02001010 *
1011 * Must be called from a cpus_read_lock() protected region
Thomas Gleixner95966952017-05-24 10:15:17 +02001012 */
1013struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq)
1014{
Sebastian Andrzej Siewiorc5a81c82017-05-24 10:15:18 +02001015 lockdep_assert_cpus_held();
Thomas Gleixner95966952017-05-24 10:15:17 +02001016 return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask);
1017}
1018EXPORT_SYMBOL(padata_alloc_possible);
1019
1020/**
Steffen Klassert16295be2010-01-06 19:47:10 +11001021 * padata_free - free a padata instance
1022 *
Steffen Klassert0198ffd2010-05-19 13:44:27 +10001023 * @padata_inst: padata instance to free
Steffen Klassert16295be2010-01-06 19:47:10 +11001024 */
1025void padata_free(struct padata_instance *pinst)
1026{
Dan Kruchinin5e017dc2010-07-14 14:33:08 +04001027 kobject_put(&pinst->kobj);
Steffen Klassert16295be2010-01-06 19:47:10 +11001028}
1029EXPORT_SYMBOL(padata_free);
Sebastian Andrzej Siewior30e92152016-09-06 19:04:49 +02001030
1031#ifdef CONFIG_HOTPLUG_CPU
1032
1033static __init int padata_driver_init(void)
1034{
1035 int ret;
1036
1037 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "padata:online",
1038 padata_cpu_online,
1039 padata_cpu_prep_down);
1040 if (ret < 0)
1041 return ret;
1042 hp_online = ret;
1043 return 0;
1044}
1045module_init(padata_driver_init);
1046
1047static __exit void padata_driver_exit(void)
1048{
1049 cpuhp_remove_multi_state(hp_online);
1050}
1051module_exit(padata_driver_exit);
1052#endif