blob: 161402f0b517c9f483f166585bd61d61bac2e3f3 [file] [log] [blame]
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>
33
Steffen Klassert97e3d942010-04-29 14:37:32 +020034#define MAX_OBJ_NUM 1000
Steffen Klassert16295be2010-01-06 19:47:10 +110035
36static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
37{
38 int cpu, target_cpu;
39
Dan Kruchinine15bacb2010-07-14 14:31:57 +040040 target_cpu = cpumask_first(pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +110041 for (cpu = 0; cpu < cpu_index; cpu++)
Dan Kruchinine15bacb2010-07-14 14:31:57 +040042 target_cpu = cpumask_next(target_cpu, pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +110043
44 return target_cpu;
45}
46
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +010047static int padata_cpu_hash(struct parallel_data *pd)
Steffen Klassert16295be2010-01-06 19:47:10 +110048{
Mathias Krause0b6b0982013-10-25 12:14:15 +020049 unsigned int seq_nr;
Steffen Klassert16295be2010-01-06 19:47:10 +110050 int cpu_index;
Steffen Klassert16295be2010-01-06 19:47:10 +110051
52 /*
53 * Hash the sequence numbers to the cpus by taking
54 * seq_nr mod. number of cpus in use.
55 */
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +010056
Mathias Krause0b6b0982013-10-25 12:14:15 +020057 seq_nr = atomic_inc_return(&pd->seq_nr);
58 cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +110059
60 return padata_index_to_cpu(pd, cpu_index);
61}
62
Dan Kruchinine15bacb2010-07-14 14:31:57 +040063static void padata_parallel_worker(struct work_struct *parallel_work)
Steffen Klassert16295be2010-01-06 19:47:10 +110064{
Dan Kruchinine15bacb2010-07-14 14:31:57 +040065 struct padata_parallel_queue *pqueue;
Steffen Klassert16295be2010-01-06 19:47:10 +110066 struct parallel_data *pd;
67 struct padata_instance *pinst;
68 LIST_HEAD(local_list);
69
70 local_bh_disable();
Dan Kruchinine15bacb2010-07-14 14:31:57 +040071 pqueue = container_of(parallel_work,
72 struct padata_parallel_queue, work);
73 pd = pqueue->pd;
Steffen Klassert16295be2010-01-06 19:47:10 +110074 pinst = pd->pinst;
75
Dan Kruchinine15bacb2010-07-14 14:31:57 +040076 spin_lock(&pqueue->parallel.lock);
77 list_replace_init(&pqueue->parallel.list, &local_list);
78 spin_unlock(&pqueue->parallel.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +110079
80 while (!list_empty(&local_list)) {
81 struct padata_priv *padata;
82
83 padata = list_entry(local_list.next,
84 struct padata_priv, list);
85
86 list_del_init(&padata->list);
87
88 padata->parallel(padata);
89 }
90
91 local_bh_enable();
92}
93
Steffen Klassert0198ffd2010-05-19 13:44:27 +100094/**
Steffen Klassert16295be2010-01-06 19:47:10 +110095 * padata_do_parallel - padata parallelization function
96 *
97 * @pinst: padata instance
98 * @padata: object to be parallelized
99 * @cb_cpu: cpu the serialization callback function will run on,
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400100 * must be in the serial cpumask of padata(i.e. cpumask.cbcpu).
Steffen Klassert16295be2010-01-06 19:47:10 +1100101 *
102 * The parallelization callback function will run with BHs off.
103 * Note: Every object which is parallelized by padata_do_parallel
104 * must be seen by padata_do_serial.
105 */
106int padata_do_parallel(struct padata_instance *pinst,
107 struct padata_priv *padata, int cb_cpu)
108{
109 int target_cpu, err;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400110 struct padata_parallel_queue *queue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100111 struct parallel_data *pd;
112
113 rcu_read_lock_bh();
114
Mathias Krausec0e656b2013-11-28 19:20:05 +0100115 pd = rcu_dereference_bh(pinst->pd);
Steffen Klassert16295be2010-01-06 19:47:10 +1100116
Steffen Klassert83f619f2010-07-07 15:32:02 +0200117 err = -EINVAL;
Steffen Klassert74247132010-07-20 08:51:25 +0200118 if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID)
Steffen Klassert16295be2010-01-06 19:47:10 +1100119 goto out;
120
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400121 if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu))
Steffen Klassert16295be2010-01-06 19:47:10 +1100122 goto out;
123
124 err = -EBUSY;
125 if ((pinst->flags & PADATA_RESET))
126 goto out;
127
128 if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM)
129 goto out;
130
Steffen Klassert83f619f2010-07-07 15:32:02 +0200131 err = 0;
Steffen Klassert16295be2010-01-06 19:47:10 +1100132 atomic_inc(&pd->refcnt);
133 padata->pd = pd;
134 padata->cb_cpu = cb_cpu;
135
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100136 target_cpu = padata_cpu_hash(pd);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400137 queue = per_cpu_ptr(pd->pqueue, target_cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100138
139 spin_lock(&queue->parallel.lock);
140 list_add_tail(&padata->list, &queue->parallel.list);
141 spin_unlock(&queue->parallel.lock);
142
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400143 queue_work_on(target_cpu, pinst->wq, &queue->work);
Steffen Klassert16295be2010-01-06 19:47:10 +1100144
145out:
146 rcu_read_unlock_bh();
147
148 return err;
149}
150EXPORT_SYMBOL(padata_do_parallel);
151
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000152/*
153 * padata_get_next - Get the next object that needs serialization.
154 *
155 * Return values are:
156 *
157 * A pointer to the control struct of the next object that needs
158 * serialization, if present in one of the percpu reorder queues.
159 *
160 * NULL, if all percpu reorder queues are empty.
161 *
162 * -EINPROGRESS, if the next object that needs serialization will
163 * be parallel processed by another cpu and is not yet present in
164 * the cpu's reorder queue.
165 *
166 * -ENODATA, if this cpu has to do the parallel processing for
167 * the next object.
168 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100169static struct padata_priv *padata_get_next(struct parallel_data *pd)
170{
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200171 int cpu, num_cpus;
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100172 unsigned int next_nr, next_index;
Shan Weif0fcf202012-12-06 17:16:23 +0800173 struct padata_parallel_queue *next_queue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100174 struct padata_priv *padata;
175 struct padata_list *reorder;
176
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400177 num_cpus = cpumask_weight(pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100178
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200179 /*
180 * Calculate the percpu reorder queue and the sequence
181 * number of the next object.
182 */
183 next_nr = pd->processed;
184 next_index = next_nr % num_cpus;
185 cpu = padata_index_to_cpu(pd, next_index);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400186 next_queue = per_cpu_ptr(pd->pqueue, cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100187
Steffen Klassert16295be2010-01-06 19:47:10 +1100188 padata = NULL;
189
Steffen Klassert16295be2010-01-06 19:47:10 +1100190 reorder = &next_queue->reorder;
191
192 if (!list_empty(&reorder->list)) {
193 padata = list_entry(reorder->list.next,
194 struct padata_priv, list);
195
Steffen Klassert16295be2010-01-06 19:47:10 +1100196 spin_lock(&reorder->lock);
197 list_del_init(&padata->list);
198 atomic_dec(&pd->reorder_objects);
199 spin_unlock(&reorder->lock);
200
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200201 pd->processed++;
Steffen Klassert16295be2010-01-06 19:47:10 +1100202
203 goto out;
204 }
205
Shan Weif0fcf202012-12-06 17:16:23 +0800206 if (__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index) {
Steffen Klassert16295be2010-01-06 19:47:10 +1100207 padata = ERR_PTR(-ENODATA);
208 goto out;
209 }
210
211 padata = ERR_PTR(-EINPROGRESS);
212out:
213 return padata;
214}
215
216static void padata_reorder(struct parallel_data *pd)
217{
Steffen Klassert30478172012-03-09 07:20:12 +0100218 int cb_cpu;
Steffen Klassert16295be2010-01-06 19:47:10 +1100219 struct padata_priv *padata;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400220 struct padata_serial_queue *squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100221 struct padata_instance *pinst = pd->pinst;
222
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000223 /*
224 * We need to ensure that only one cpu can work on dequeueing of
225 * the reorder queue the time. Calculating in which percpu reorder
226 * queue the next object will arrive takes some time. A spinlock
227 * would be highly contended. Also it is not clear in which order
228 * the objects arrive to the reorder queues. So a cpu could wait to
229 * get the lock just to notice that there is nothing to do at the
230 * moment. Therefore we use a trylock and let the holder of the lock
231 * care for all the objects enqueued during the holdtime of the lock.
232 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100233 if (!spin_trylock_bh(&pd->lock))
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000234 return;
Steffen Klassert16295be2010-01-06 19:47:10 +1100235
236 while (1) {
237 padata = padata_get_next(pd);
238
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000239 /*
240 * All reorder queues are empty, or the next object that needs
241 * serialization is parallel processed by another cpu and is
242 * still on it's way to the cpu's reorder queue, nothing to
243 * do for now.
244 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100245 if (!padata || PTR_ERR(padata) == -EINPROGRESS)
246 break;
247
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000248 /*
249 * This cpu has to do the parallel processing of the next
250 * object. It's waiting in the cpu's parallelization queue,
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300251 * so exit immediately.
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000252 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100253 if (PTR_ERR(padata) == -ENODATA) {
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000254 del_timer(&pd->timer);
Steffen Klassert16295be2010-01-06 19:47:10 +1100255 spin_unlock_bh(&pd->lock);
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000256 return;
Steffen Klassert16295be2010-01-06 19:47:10 +1100257 }
258
Steffen Klassert30478172012-03-09 07:20:12 +0100259 cb_cpu = padata->cb_cpu;
260 squeue = per_cpu_ptr(pd->squeue, cb_cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100261
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400262 spin_lock(&squeue->serial.lock);
263 list_add_tail(&padata->list, &squeue->serial.list);
264 spin_unlock(&squeue->serial.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100265
Steffen Klassert30478172012-03-09 07:20:12 +0100266 queue_work_on(cb_cpu, pinst->wq, &squeue->work);
Steffen Klassert16295be2010-01-06 19:47:10 +1100267 }
268
269 spin_unlock_bh(&pd->lock);
270
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000271 /*
272 * The next object that needs serialization might have arrived to
273 * the reorder queues in the meantime, we will be called again
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300274 * from the timer function if no one else cares for it.
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000275 */
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000276 if (atomic_read(&pd->reorder_objects)
277 && !(pinst->flags & PADATA_RESET))
278 mod_timer(&pd->timer, jiffies + HZ);
279 else
280 del_timer(&pd->timer);
Steffen Klassert16295be2010-01-06 19:47:10 +1100281
Steffen Klassert16295be2010-01-06 19:47:10 +1100282 return;
283}
284
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000285static void padata_reorder_timer(unsigned long arg)
286{
287 struct parallel_data *pd = (struct parallel_data *)arg;
288
289 padata_reorder(pd);
290}
291
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400292static void padata_serial_worker(struct work_struct *serial_work)
Steffen Klassert16295be2010-01-06 19:47:10 +1100293{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400294 struct padata_serial_queue *squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100295 struct parallel_data *pd;
296 LIST_HEAD(local_list);
297
298 local_bh_disable();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400299 squeue = container_of(serial_work, struct padata_serial_queue, work);
300 pd = squeue->pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100301
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400302 spin_lock(&squeue->serial.lock);
303 list_replace_init(&squeue->serial.list, &local_list);
304 spin_unlock(&squeue->serial.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100305
306 while (!list_empty(&local_list)) {
307 struct padata_priv *padata;
308
309 padata = list_entry(local_list.next,
310 struct padata_priv, list);
311
312 list_del_init(&padata->list);
313
314 padata->serial(padata);
315 atomic_dec(&pd->refcnt);
316 }
317 local_bh_enable();
318}
319
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000320/**
Steffen Klassert16295be2010-01-06 19:47:10 +1100321 * padata_do_serial - padata serialization function
322 *
323 * @padata: object to be serialized.
324 *
325 * padata_do_serial must be called for every parallelized object.
326 * The serialization callback function will run with BHs off.
327 */
328void padata_do_serial(struct padata_priv *padata)
329{
330 int cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400331 struct padata_parallel_queue *pqueue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100332 struct parallel_data *pd;
333
334 pd = padata->pd;
335
336 cpu = get_cpu();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400337 pqueue = per_cpu_ptr(pd->pqueue, cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100338
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400339 spin_lock(&pqueue->reorder.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100340 atomic_inc(&pd->reorder_objects);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400341 list_add_tail(&padata->list, &pqueue->reorder.list);
342 spin_unlock(&pqueue->reorder.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100343
344 put_cpu();
345
346 padata_reorder(pd);
347}
348EXPORT_SYMBOL(padata_do_serial);
349
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400350static int padata_setup_cpumasks(struct parallel_data *pd,
351 const struct cpumask *pcpumask,
352 const struct cpumask *cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100353{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400354 if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL))
355 return -ENOMEM;
356
Steffen Klassert13614e02012-03-28 08:43:21 +0200357 cpumask_and(pd->cpumask.pcpu, pcpumask, cpu_online_mask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400358 if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) {
359 free_cpumask_var(pd->cpumask.cbcpu);
360 return -ENOMEM;
361 }
362
Steffen Klassert13614e02012-03-28 08:43:21 +0200363 cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_online_mask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400364 return 0;
365}
366
367static void __padata_list_init(struct padata_list *pd_list)
368{
369 INIT_LIST_HEAD(&pd_list->list);
370 spin_lock_init(&pd_list->lock);
371}
372
373/* Initialize all percpu queues used by serial workers */
374static void padata_init_squeues(struct parallel_data *pd)
375{
376 int cpu;
377 struct padata_serial_queue *squeue;
378
379 for_each_cpu(cpu, pd->cpumask.cbcpu) {
380 squeue = per_cpu_ptr(pd->squeue, cpu);
381 squeue->pd = pd;
382 __padata_list_init(&squeue->serial);
383 INIT_WORK(&squeue->work, padata_serial_worker);
384 }
385}
386
387/* Initialize all percpu queues used by parallel workers */
388static void padata_init_pqueues(struct parallel_data *pd)
389{
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100390 int cpu_index, cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400391 struct padata_parallel_queue *pqueue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100392
393 cpu_index = 0;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400394 for_each_cpu(cpu, pd->cpumask.pcpu) {
395 pqueue = per_cpu_ptr(pd->pqueue, cpu);
396 pqueue->pd = pd;
397 pqueue->cpu_index = cpu_index;
Steffen Klassertfad3a902010-07-20 08:48:34 +0200398 cpu_index++;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400399
400 __padata_list_init(&pqueue->reorder);
401 __padata_list_init(&pqueue->parallel);
402 INIT_WORK(&pqueue->work, padata_parallel_worker);
403 atomic_set(&pqueue->num_obj, 0);
404 }
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400405}
406
407/* Allocate and initialize the internal cpumask dependend resources. */
408static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
409 const struct cpumask *pcpumask,
410 const struct cpumask *cbcpumask)
411{
412 struct parallel_data *pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100413
414 pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL);
415 if (!pd)
416 goto err;
417
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400418 pd->pqueue = alloc_percpu(struct padata_parallel_queue);
419 if (!pd->pqueue)
Steffen Klassert16295be2010-01-06 19:47:10 +1100420 goto err_free_pd;
421
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400422 pd->squeue = alloc_percpu(struct padata_serial_queue);
423 if (!pd->squeue)
424 goto err_free_pqueue;
425 if (padata_setup_cpumasks(pd, pcpumask, cbcpumask) < 0)
426 goto err_free_squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100427
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400428 padata_init_pqueues(pd);
429 padata_init_squeues(pd);
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000430 setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd);
Mathias Krause0b6b0982013-10-25 12:14:15 +0200431 atomic_set(&pd->seq_nr, -1);
Steffen Klassert16295be2010-01-06 19:47:10 +1100432 atomic_set(&pd->reorder_objects, 0);
433 atomic_set(&pd->refcnt, 0);
434 pd->pinst = pinst;
435 spin_lock_init(&pd->lock);
436
437 return pd;
438
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400439err_free_squeue:
440 free_percpu(pd->squeue);
441err_free_pqueue:
442 free_percpu(pd->pqueue);
Steffen Klassert16295be2010-01-06 19:47:10 +1100443err_free_pd:
444 kfree(pd);
445err:
446 return NULL;
447}
448
449static void padata_free_pd(struct parallel_data *pd)
450{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400451 free_cpumask_var(pd->cpumask.pcpu);
452 free_cpumask_var(pd->cpumask.cbcpu);
453 free_percpu(pd->pqueue);
454 free_percpu(pd->squeue);
Steffen Klassert16295be2010-01-06 19:47:10 +1100455 kfree(pd);
456}
457
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000458/* Flush all objects out of the padata queues. */
Steffen Klassert2b73b072010-05-19 13:43:46 +1000459static void padata_flush_queues(struct parallel_data *pd)
460{
461 int cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400462 struct padata_parallel_queue *pqueue;
463 struct padata_serial_queue *squeue;
Steffen Klassert2b73b072010-05-19 13:43:46 +1000464
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400465 for_each_cpu(cpu, pd->cpumask.pcpu) {
466 pqueue = per_cpu_ptr(pd->pqueue, cpu);
467 flush_work(&pqueue->work);
Steffen Klassert2b73b072010-05-19 13:43:46 +1000468 }
469
470 del_timer_sync(&pd->timer);
471
472 if (atomic_read(&pd->reorder_objects))
473 padata_reorder(pd);
474
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400475 for_each_cpu(cpu, pd->cpumask.cbcpu) {
476 squeue = per_cpu_ptr(pd->squeue, cpu);
477 flush_work(&squeue->work);
Steffen Klassert2b73b072010-05-19 13:43:46 +1000478 }
479
480 BUG_ON(atomic_read(&pd->refcnt) != 0);
481}
482
Steffen Klassert4c879172010-07-07 15:30:10 +0200483static void __padata_start(struct padata_instance *pinst)
484{
485 pinst->flags |= PADATA_INIT;
486}
487
Steffen Klassertee836552010-07-07 15:30:47 +0200488static void __padata_stop(struct padata_instance *pinst)
489{
490 if (!(pinst->flags & PADATA_INIT))
491 return;
492
493 pinst->flags &= ~PADATA_INIT;
494
495 synchronize_rcu();
496
497 get_online_cpus();
498 padata_flush_queues(pinst->pd);
499 put_online_cpus();
500}
501
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300502/* Replace the internal control structure with a new one. */
Steffen Klassert16295be2010-01-06 19:47:10 +1100503static void padata_replace(struct padata_instance *pinst,
504 struct parallel_data *pd_new)
505{
506 struct parallel_data *pd_old = pinst->pd;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400507 int notification_mask = 0;
Steffen Klassert16295be2010-01-06 19:47:10 +1100508
509 pinst->flags |= PADATA_RESET;
510
511 rcu_assign_pointer(pinst->pd, pd_new);
512
513 synchronize_rcu();
514
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400515 if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu))
516 notification_mask |= PADATA_CPU_PARALLEL;
517 if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu))
518 notification_mask |= PADATA_CPU_SERIAL;
Steffen Klassert16295be2010-01-06 19:47:10 +1100519
Steffen Klassert16295be2010-01-06 19:47:10 +1100520 padata_flush_queues(pd_old);
521 padata_free_pd(pd_old);
522
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400523 if (notification_mask)
524 blocking_notifier_call_chain(&pinst->cpumask_change_notifier,
Steffen Klassertc6356962010-07-27 07:15:50 +0200525 notification_mask,
526 &pd_new->cpumask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400527
Steffen Klassert16295be2010-01-06 19:47:10 +1100528 pinst->flags &= ~PADATA_RESET;
529}
530
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000531/**
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400532 * padata_register_cpumask_notifier - Registers a notifier that will be called
533 * if either pcpu or cbcpu or both cpumasks change.
Steffen Klassert16295be2010-01-06 19:47:10 +1100534 *
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400535 * @pinst: A poineter to padata instance
536 * @nblock: A pointer to notifier block.
Steffen Klassert16295be2010-01-06 19:47:10 +1100537 */
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400538int padata_register_cpumask_notifier(struct padata_instance *pinst,
539 struct notifier_block *nblock)
Steffen Klassert16295be2010-01-06 19:47:10 +1100540{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400541 return blocking_notifier_chain_register(&pinst->cpumask_change_notifier,
542 nblock);
543}
544EXPORT_SYMBOL(padata_register_cpumask_notifier);
Steffen Klassert16295be2010-01-06 19:47:10 +1100545
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400546/**
547 * padata_unregister_cpumask_notifier - Unregisters cpumask notifier
548 * registered earlier using padata_register_cpumask_notifier
549 *
550 * @pinst: A pointer to data instance.
551 * @nlock: A pointer to notifier block.
552 */
553int padata_unregister_cpumask_notifier(struct padata_instance *pinst,
554 struct notifier_block *nblock)
555{
556 return blocking_notifier_chain_unregister(
557 &pinst->cpumask_change_notifier,
558 nblock);
559}
560EXPORT_SYMBOL(padata_unregister_cpumask_notifier);
Steffen Klassert16295be2010-01-06 19:47:10 +1100561
Steffen Klassert6751fb32010-04-29 14:42:30 +0200562
Steffen Klassert33e54452010-07-07 15:31:26 +0200563/* If cpumask contains no active cpu, we mark the instance as invalid. */
564static bool padata_validate_cpumask(struct padata_instance *pinst,
565 const struct cpumask *cpumask)
566{
Steffen Klassert13614e02012-03-28 08:43:21 +0200567 if (!cpumask_intersects(cpumask, cpu_online_mask)) {
Steffen Klassert33e54452010-07-07 15:31:26 +0200568 pinst->flags |= PADATA_INVALID;
569 return false;
Steffen Klassert16295be2010-01-06 19:47:10 +1100570 }
571
Steffen Klassert33e54452010-07-07 15:31:26 +0200572 pinst->flags &= ~PADATA_INVALID;
573 return true;
574}
575
Steffen Klassert65ff5772010-07-27 07:15:06 +0200576static int __padata_set_cpumasks(struct padata_instance *pinst,
577 cpumask_var_t pcpumask,
578 cpumask_var_t cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100579{
Steffen Klassert33e54452010-07-07 15:31:26 +0200580 int valid;
Steffen Klassert65ff5772010-07-27 07:15:06 +0200581 struct parallel_data *pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100582
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400583 valid = padata_validate_cpumask(pinst, pcpumask);
584 if (!valid) {
585 __padata_stop(pinst);
586 goto out_replace;
587 }
588
589 valid = padata_validate_cpumask(pinst, cbcpumask);
Steffen Klassertb89661d2010-07-20 08:49:20 +0200590 if (!valid)
Steffen Klassert33e54452010-07-07 15:31:26 +0200591 __padata_stop(pinst);
Steffen Klassert33e54452010-07-07 15:31:26 +0200592
Steffen Klassertb89661d2010-07-20 08:49:20 +0200593out_replace:
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400594 pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
Steffen Klassert65ff5772010-07-27 07:15:06 +0200595 if (!pd)
596 return -ENOMEM;
Steffen Klassert16295be2010-01-06 19:47:10 +1100597
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400598 cpumask_copy(pinst->cpumask.pcpu, pcpumask);
599 cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
Steffen Klassert16295be2010-01-06 19:47:10 +1100600
601 padata_replace(pinst, pd);
602
Steffen Klassert33e54452010-07-07 15:31:26 +0200603 if (valid)
604 __padata_start(pinst);
605
Steffen Klassert65ff5772010-07-27 07:15:06 +0200606 return 0;
607}
608
609/**
610 * padata_set_cpumasks - Set both parallel and serial cpumasks. The first
611 * one is used by parallel workers and the second one
612 * by the wokers doing serialization.
613 *
614 * @pinst: padata instance
615 * @pcpumask: the cpumask to use for parallel workers
616 * @cbcpumask: the cpumsak to use for serial workers
617 */
618int padata_set_cpumasks(struct padata_instance *pinst, cpumask_var_t pcpumask,
619 cpumask_var_t cbcpumask)
620{
621 int err;
622
623 mutex_lock(&pinst->lock);
624 get_online_cpus();
625
626 err = __padata_set_cpumasks(pinst, pcpumask, cbcpumask);
627
Steffen Klassert6751fb32010-04-29 14:42:30 +0200628 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100629 mutex_unlock(&pinst->lock);
630
631 return err;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400632
Steffen Klassert16295be2010-01-06 19:47:10 +1100633}
Steffen Klassert65ff5772010-07-27 07:15:06 +0200634EXPORT_SYMBOL(padata_set_cpumasks);
635
636/**
637 * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value
638 * equivalent to @cpumask.
639 *
640 * @pinst: padata instance
641 * @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding
642 * to parallel and serial cpumasks respectively.
643 * @cpumask: the cpumask to use
644 */
645int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
646 cpumask_var_t cpumask)
647{
648 struct cpumask *serial_mask, *parallel_mask;
649 int err = -EINVAL;
650
651 mutex_lock(&pinst->lock);
652 get_online_cpus();
653
654 switch (cpumask_type) {
655 case PADATA_CPU_PARALLEL:
656 serial_mask = pinst->cpumask.cbcpu;
657 parallel_mask = cpumask;
658 break;
659 case PADATA_CPU_SERIAL:
660 parallel_mask = pinst->cpumask.pcpu;
661 serial_mask = cpumask;
662 break;
663 default:
664 goto out;
665 }
666
667 err = __padata_set_cpumasks(pinst, parallel_mask, serial_mask);
668
Steffen Klassert16295be2010-01-06 19:47:10 +1100669out:
670 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100671 mutex_unlock(&pinst->lock);
672
673 return err;
674}
675EXPORT_SYMBOL(padata_set_cpumask);
676
677static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
678{
679 struct parallel_data *pd;
680
Steffen Klassert13614e02012-03-28 08:43:21 +0200681 if (cpumask_test_cpu(cpu, cpu_online_mask)) {
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400682 pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
683 pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100684 if (!pd)
685 return -ENOMEM;
686
687 padata_replace(pinst, pd);
Steffen Klassert33e54452010-07-07 15:31:26 +0200688
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400689 if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) &&
690 padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
Steffen Klassert33e54452010-07-07 15:31:26 +0200691 __padata_start(pinst);
Steffen Klassert16295be2010-01-06 19:47:10 +1100692 }
693
694 return 0;
695}
696
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400697 /**
698 * padata_add_cpu - add a cpu to one or both(parallel and serial)
699 * padata cpumasks.
Steffen Klassert16295be2010-01-06 19:47:10 +1100700 *
701 * @pinst: padata instance
702 * @cpu: cpu to add
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400703 * @mask: bitmask of flags specifying to which cpumask @cpu shuld be added.
704 * The @mask may be any combination of the following flags:
705 * PADATA_CPU_SERIAL - serial cpumask
706 * PADATA_CPU_PARALLEL - parallel cpumask
Steffen Klassert16295be2010-01-06 19:47:10 +1100707 */
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400708
709int padata_add_cpu(struct padata_instance *pinst, int cpu, int mask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100710{
711 int err;
712
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400713 if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL)))
714 return -EINVAL;
715
Steffen Klassert16295be2010-01-06 19:47:10 +1100716 mutex_lock(&pinst->lock);
717
Steffen Klassert6751fb32010-04-29 14:42:30 +0200718 get_online_cpus();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400719 if (mask & PADATA_CPU_SERIAL)
720 cpumask_set_cpu(cpu, pinst->cpumask.cbcpu);
721 if (mask & PADATA_CPU_PARALLEL)
722 cpumask_set_cpu(cpu, pinst->cpumask.pcpu);
723
Steffen Klassert16295be2010-01-06 19:47:10 +1100724 err = __padata_add_cpu(pinst, cpu);
Steffen Klassert6751fb32010-04-29 14:42:30 +0200725 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100726
727 mutex_unlock(&pinst->lock);
728
729 return err;
730}
731EXPORT_SYMBOL(padata_add_cpu);
732
733static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
734{
Steffen Klassert33e54452010-07-07 15:31:26 +0200735 struct parallel_data *pd = NULL;
Steffen Klassert16295be2010-01-06 19:47:10 +1100736
737 if (cpumask_test_cpu(cpu, cpu_online_mask)) {
Steffen Klassert33e54452010-07-07 15:31:26 +0200738
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400739 if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) ||
Steffen Klassertb89661d2010-07-20 08:49:20 +0200740 !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
Steffen Klassert33e54452010-07-07 15:31:26 +0200741 __padata_stop(pinst);
Steffen Klassert33e54452010-07-07 15:31:26 +0200742
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400743 pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
744 pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100745 if (!pd)
746 return -ENOMEM;
747
748 padata_replace(pinst, pd);
Steffen Klassert96120902012-03-28 08:44:07 +0200749
750 cpumask_clear_cpu(cpu, pd->cpumask.cbcpu);
751 cpumask_clear_cpu(cpu, pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100752 }
753
754 return 0;
755}
756
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400757 /**
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300758 * padata_remove_cpu - remove a cpu from the one or both(serial and parallel)
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400759 * padata cpumasks.
Steffen Klassert16295be2010-01-06 19:47:10 +1100760 *
761 * @pinst: padata instance
762 * @cpu: cpu to remove
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400763 * @mask: bitmask specifying from which cpumask @cpu should be removed
764 * The @mask may be any combination of the following flags:
765 * PADATA_CPU_SERIAL - serial cpumask
766 * PADATA_CPU_PARALLEL - parallel cpumask
Steffen Klassert16295be2010-01-06 19:47:10 +1100767 */
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400768int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100769{
770 int err;
771
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400772 if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL)))
773 return -EINVAL;
774
Steffen Klassert16295be2010-01-06 19:47:10 +1100775 mutex_lock(&pinst->lock);
776
Steffen Klassert6751fb32010-04-29 14:42:30 +0200777 get_online_cpus();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400778 if (mask & PADATA_CPU_SERIAL)
779 cpumask_clear_cpu(cpu, pinst->cpumask.cbcpu);
780 if (mask & PADATA_CPU_PARALLEL)
781 cpumask_clear_cpu(cpu, pinst->cpumask.pcpu);
782
Steffen Klassert16295be2010-01-06 19:47:10 +1100783 err = __padata_remove_cpu(pinst, cpu);
Steffen Klassert6751fb32010-04-29 14:42:30 +0200784 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100785
786 mutex_unlock(&pinst->lock);
787
788 return err;
789}
790EXPORT_SYMBOL(padata_remove_cpu);
791
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000792/**
Steffen Klassert16295be2010-01-06 19:47:10 +1100793 * padata_start - start the parallel processing
794 *
795 * @pinst: padata instance to start
796 */
Steffen Klassert4c879172010-07-07 15:30:10 +0200797int padata_start(struct padata_instance *pinst)
Steffen Klassert16295be2010-01-06 19:47:10 +1100798{
Steffen Klassert4c879172010-07-07 15:30:10 +0200799 int err = 0;
800
Steffen Klassert16295be2010-01-06 19:47:10 +1100801 mutex_lock(&pinst->lock);
Steffen Klassert4c879172010-07-07 15:30:10 +0200802
803 if (pinst->flags & PADATA_INVALID)
804 err =-EINVAL;
805
806 __padata_start(pinst);
807
Steffen Klassert16295be2010-01-06 19:47:10 +1100808 mutex_unlock(&pinst->lock);
Steffen Klassert4c879172010-07-07 15:30:10 +0200809
810 return err;
Steffen Klassert16295be2010-01-06 19:47:10 +1100811}
812EXPORT_SYMBOL(padata_start);
813
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000814/**
Steffen Klassert16295be2010-01-06 19:47:10 +1100815 * padata_stop - stop the parallel processing
816 *
817 * @pinst: padata instance to stop
818 */
819void padata_stop(struct padata_instance *pinst)
820{
Steffen Klassert16295be2010-01-06 19:47:10 +1100821 mutex_lock(&pinst->lock);
Steffen Klassertee836552010-07-07 15:30:47 +0200822 __padata_stop(pinst);
Steffen Klassert16295be2010-01-06 19:47:10 +1100823 mutex_unlock(&pinst->lock);
824}
825EXPORT_SYMBOL(padata_stop);
826
Steffen Klasserte2cb2f12010-04-29 14:40:10 +0200827#ifdef CONFIG_HOTPLUG_CPU
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400828
829static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu)
830{
831 return cpumask_test_cpu(cpu, pinst->cpumask.pcpu) ||
832 cpumask_test_cpu(cpu, pinst->cpumask.cbcpu);
833}
834
835
Henrik Kretzschmar975d2602010-03-29 16:15:31 +0800836static int padata_cpu_callback(struct notifier_block *nfb,
837 unsigned long action, void *hcpu)
Steffen Klassert16295be2010-01-06 19:47:10 +1100838{
839 int err;
840 struct padata_instance *pinst;
841 int cpu = (unsigned long)hcpu;
842
843 pinst = container_of(nfb, struct padata_instance, cpu_notifier);
844
845 switch (action) {
846 case CPU_ONLINE:
847 case CPU_ONLINE_FROZEN:
Chen Gang9c823f92013-08-22 06:43:37 +0000848 case CPU_DOWN_FAILED:
849 case CPU_DOWN_FAILED_FROZEN:
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400850 if (!pinst_has_cpu(pinst, cpu))
Steffen Klassert16295be2010-01-06 19:47:10 +1100851 break;
852 mutex_lock(&pinst->lock);
853 err = __padata_add_cpu(pinst, cpu);
854 mutex_unlock(&pinst->lock);
855 if (err)
Akinobu Mita80b51842010-05-26 14:43:32 -0700856 return notifier_from_errno(err);
Steffen Klassert16295be2010-01-06 19:47:10 +1100857 break;
858
859 case CPU_DOWN_PREPARE:
860 case CPU_DOWN_PREPARE_FROZEN:
Chen Gang9c823f92013-08-22 06:43:37 +0000861 case CPU_UP_CANCELED:
862 case CPU_UP_CANCELED_FROZEN:
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400863 if (!pinst_has_cpu(pinst, cpu))
Steffen Klassert16295be2010-01-06 19:47:10 +1100864 break;
865 mutex_lock(&pinst->lock);
866 err = __padata_remove_cpu(pinst, cpu);
867 mutex_unlock(&pinst->lock);
868 if (err)
Akinobu Mita80b51842010-05-26 14:43:32 -0700869 return notifier_from_errno(err);
Steffen Klassert16295be2010-01-06 19:47:10 +1100870 break;
Steffen Klassert16295be2010-01-06 19:47:10 +1100871 }
872
873 return NOTIFY_OK;
874}
Steffen Klasserte2cb2f12010-04-29 14:40:10 +0200875#endif
Steffen Klassert16295be2010-01-06 19:47:10 +1100876
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400877static void __padata_free(struct padata_instance *pinst)
878{
879#ifdef CONFIG_HOTPLUG_CPU
880 unregister_hotcpu_notifier(&pinst->cpu_notifier);
881#endif
882
883 padata_stop(pinst);
884 padata_free_pd(pinst->pd);
885 free_cpumask_var(pinst->cpumask.pcpu);
886 free_cpumask_var(pinst->cpumask.cbcpu);
887 kfree(pinst);
888}
889
890#define kobj2pinst(_kobj) \
891 container_of(_kobj, struct padata_instance, kobj)
892#define attr2pentry(_attr) \
893 container_of(_attr, struct padata_sysfs_entry, attr)
894
895static void padata_sysfs_release(struct kobject *kobj)
896{
897 struct padata_instance *pinst = kobj2pinst(kobj);
898 __padata_free(pinst);
899}
900
901struct padata_sysfs_entry {
902 struct attribute attr;
903 ssize_t (*show)(struct padata_instance *, struct attribute *, char *);
904 ssize_t (*store)(struct padata_instance *, struct attribute *,
905 const char *, size_t);
906};
907
908static ssize_t show_cpumask(struct padata_instance *pinst,
909 struct attribute *attr, char *buf)
910{
911 struct cpumask *cpumask;
912 ssize_t len;
913
914 mutex_lock(&pinst->lock);
915 if (!strcmp(attr->name, "serial_cpumask"))
916 cpumask = pinst->cpumask.cbcpu;
917 else
918 cpumask = pinst->cpumask.pcpu;
919
920 len = bitmap_scnprintf(buf, PAGE_SIZE, cpumask_bits(cpumask),
921 nr_cpu_ids);
922 if (PAGE_SIZE - len < 2)
923 len = -EINVAL;
924 else
925 len += sprintf(buf + len, "\n");
926
927 mutex_unlock(&pinst->lock);
928 return len;
929}
930
931static ssize_t store_cpumask(struct padata_instance *pinst,
932 struct attribute *attr,
933 const char *buf, size_t count)
934{
935 cpumask_var_t new_cpumask;
936 ssize_t ret;
937 int mask_type;
938
939 if (!alloc_cpumask_var(&new_cpumask, GFP_KERNEL))
940 return -ENOMEM;
941
942 ret = bitmap_parse(buf, count, cpumask_bits(new_cpumask),
943 nr_cpumask_bits);
944 if (ret < 0)
945 goto out;
946
947 mask_type = !strcmp(attr->name, "serial_cpumask") ?
948 PADATA_CPU_SERIAL : PADATA_CPU_PARALLEL;
949 ret = padata_set_cpumask(pinst, mask_type, new_cpumask);
950 if (!ret)
951 ret = count;
952
953out:
954 free_cpumask_var(new_cpumask);
955 return ret;
956}
957
958#define PADATA_ATTR_RW(_name, _show_name, _store_name) \
959 static struct padata_sysfs_entry _name##_attr = \
960 __ATTR(_name, 0644, _show_name, _store_name)
961#define PADATA_ATTR_RO(_name, _show_name) \
962 static struct padata_sysfs_entry _name##_attr = \
963 __ATTR(_name, 0400, _show_name, NULL)
964
965PADATA_ATTR_RW(serial_cpumask, show_cpumask, store_cpumask);
966PADATA_ATTR_RW(parallel_cpumask, show_cpumask, store_cpumask);
967
968/*
969 * Padata sysfs provides the following objects:
970 * serial_cpumask [RW] - cpumask for serial workers
971 * parallel_cpumask [RW] - cpumask for parallel workers
Steffen Klassert16295be2010-01-06 19:47:10 +1100972 */
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400973static struct attribute *padata_default_attrs[] = {
974 &serial_cpumask_attr.attr,
975 &parallel_cpumask_attr.attr,
976 NULL,
977};
978
979static ssize_t padata_sysfs_show(struct kobject *kobj,
980 struct attribute *attr, char *buf)
Steffen Klassert16295be2010-01-06 19:47:10 +1100981{
Steffen Klassert16295be2010-01-06 19:47:10 +1100982 struct padata_instance *pinst;
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400983 struct padata_sysfs_entry *pentry;
984 ssize_t ret = -EIO;
985
986 pinst = kobj2pinst(kobj);
987 pentry = attr2pentry(attr);
988 if (pentry->show)
989 ret = pentry->show(pinst, attr, buf);
990
991 return ret;
992}
993
994static ssize_t padata_sysfs_store(struct kobject *kobj, struct attribute *attr,
995 const char *buf, size_t count)
996{
997 struct padata_instance *pinst;
998 struct padata_sysfs_entry *pentry;
999 ssize_t ret = -EIO;
1000
1001 pinst = kobj2pinst(kobj);
1002 pentry = attr2pentry(attr);
1003 if (pentry->show)
1004 ret = pentry->store(pinst, attr, buf, count);
1005
1006 return ret;
1007}
1008
1009static const struct sysfs_ops padata_sysfs_ops = {
1010 .show = padata_sysfs_show,
1011 .store = padata_sysfs_store,
1012};
1013
1014static struct kobj_type padata_attr_type = {
1015 .sysfs_ops = &padata_sysfs_ops,
1016 .default_attrs = padata_default_attrs,
1017 .release = padata_sysfs_release,
1018};
1019
Steffen Klassert16295be2010-01-06 19:47:10 +11001020/**
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001021 * padata_alloc_possible - Allocate and initialize padata instance.
1022 * Use the cpu_possible_mask for serial and
1023 * parallel workers.
Steffen Klassert16295be2010-01-06 19:47:10 +11001024 *
Steffen Klassert16295be2010-01-06 19:47:10 +11001025 * @wq: workqueue to use for the allocated padata instance
1026 */
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001027struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq)
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001028{
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001029 return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001030}
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001031EXPORT_SYMBOL(padata_alloc_possible);
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001032
1033/**
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001034 * padata_alloc - allocate and initialize a padata instance and specify
1035 * cpumasks for serial and parallel workers.
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001036 *
1037 * @wq: workqueue to use for the allocated padata instance
1038 * @pcpumask: cpumask that will be used for padata parallelization
1039 * @cbcpumask: cpumask that will be used for padata serialization
1040 */
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001041struct padata_instance *padata_alloc(struct workqueue_struct *wq,
1042 const struct cpumask *pcpumask,
1043 const struct cpumask *cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +11001044{
1045 struct padata_instance *pinst;
Steffen Klassert33e54452010-07-07 15:31:26 +02001046 struct parallel_data *pd = NULL;
Steffen Klassert16295be2010-01-06 19:47:10 +11001047
1048 pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL);
1049 if (!pinst)
1050 goto err;
1051
Steffen Klassert6751fb32010-04-29 14:42:30 +02001052 get_online_cpus();
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001053 if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL))
Steffen Klassert16295be2010-01-06 19:47:10 +11001054 goto err_free_inst;
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001055 if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) {
1056 free_cpumask_var(pinst->cpumask.pcpu);
1057 goto err_free_inst;
Steffen Klassert33e54452010-07-07 15:31:26 +02001058 }
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001059 if (!padata_validate_cpumask(pinst, pcpumask) ||
1060 !padata_validate_cpumask(pinst, cbcpumask))
1061 goto err_free_masks;
Steffen Klassert16295be2010-01-06 19:47:10 +11001062
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001063 pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
1064 if (!pd)
1065 goto err_free_masks;
Steffen Klassert74781382010-03-04 13:30:22 +08001066
Steffen Klassert16295be2010-01-06 19:47:10 +11001067 rcu_assign_pointer(pinst->pd, pd);
1068
1069 pinst->wq = wq;
1070
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001071 cpumask_copy(pinst->cpumask.pcpu, pcpumask);
1072 cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
Steffen Klassert16295be2010-01-06 19:47:10 +11001073
1074 pinst->flags = 0;
1075
Steffen Klassert6751fb32010-04-29 14:42:30 +02001076 put_online_cpus();
1077
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001078 BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier);
Dan Kruchinin5e017dc2010-07-14 14:33:08 +04001079 kobject_init(&pinst->kobj, &padata_attr_type);
Steffen Klassert16295be2010-01-06 19:47:10 +11001080 mutex_init(&pinst->lock);
1081
Richard Weinbergerb8b4a412013-08-23 13:12:33 +02001082#ifdef CONFIG_HOTPLUG_CPU
1083 pinst->cpu_notifier.notifier_call = padata_cpu_callback;
1084 pinst->cpu_notifier.priority = 0;
1085 register_hotcpu_notifier(&pinst->cpu_notifier);
1086#endif
1087
Steffen Klassert16295be2010-01-06 19:47:10 +11001088 return pinst;
1089
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001090err_free_masks:
1091 free_cpumask_var(pinst->cpumask.pcpu);
1092 free_cpumask_var(pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +11001093err_free_inst:
1094 kfree(pinst);
Steffen Klassert6751fb32010-04-29 14:42:30 +02001095 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +11001096err:
1097 return NULL;
1098}
1099EXPORT_SYMBOL(padata_alloc);
1100
Steffen Klassert0198ffd2010-05-19 13:44:27 +10001101/**
Steffen Klassert16295be2010-01-06 19:47:10 +11001102 * padata_free - free a padata instance
1103 *
Steffen Klassert0198ffd2010-05-19 13:44:27 +10001104 * @padata_inst: padata instance to free
Steffen Klassert16295be2010-01-06 19:47:10 +11001105 */
1106void padata_free(struct padata_instance *pinst)
1107{
Dan Kruchinin5e017dc2010-07-14 14:33:08 +04001108 kobject_put(&pinst->kobj);
Steffen Klassert16295be2010-01-06 19:47:10 +11001109}
1110EXPORT_SYMBOL(padata_free);