blob: 89fe3d1b9efbc1f34351e5752dd730db3c5bbab4 [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{
49 int cpu_index;
Steffen Klassert16295be2010-01-06 19:47:10 +110050
51 /*
52 * Hash the sequence numbers to the cpus by taking
53 * seq_nr mod. number of cpus in use.
54 */
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +010055
56 spin_lock(&pd->seq_lock);
57 cpu_index = pd->seq_nr % cpumask_weight(pd->cpumask.pcpu);
58 pd->seq_nr++;
59 spin_unlock(&pd->seq_lock);
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 struct parallel_data *pd;
68 struct padata_instance *pinst;
69 LIST_HEAD(local_list);
70
71 local_bh_disable();
Dan Kruchinine15bacb2010-07-14 14:31:57 +040072 pqueue = container_of(parallel_work,
73 struct padata_parallel_queue, work);
74 pd = pqueue->pd;
Steffen Klassert16295be2010-01-06 19:47:10 +110075 pinst = pd->pinst;
76
Dan Kruchinine15bacb2010-07-14 14:31:57 +040077 spin_lock(&pqueue->parallel.lock);
78 list_replace_init(&pqueue->parallel.list, &local_list);
79 spin_unlock(&pqueue->parallel.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +110080
81 while (!list_empty(&local_list)) {
82 struct padata_priv *padata;
83
84 padata = list_entry(local_list.next,
85 struct padata_priv, list);
86
87 list_del_init(&padata->list);
88
89 padata->parallel(padata);
90 }
91
92 local_bh_enable();
93}
94
Steffen Klassert0198ffd2010-05-19 13:44:27 +100095/**
Steffen Klassert16295be2010-01-06 19:47:10 +110096 * padata_do_parallel - padata parallelization function
97 *
98 * @pinst: padata instance
99 * @padata: object to be parallelized
100 * @cb_cpu: cpu the serialization callback function will run on,
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400101 * must be in the serial cpumask of padata(i.e. cpumask.cbcpu).
Steffen Klassert16295be2010-01-06 19:47:10 +1100102 *
103 * The parallelization callback function will run with BHs off.
104 * Note: Every object which is parallelized by padata_do_parallel
105 * must be seen by padata_do_serial.
106 */
107int padata_do_parallel(struct padata_instance *pinst,
108 struct padata_priv *padata, int cb_cpu)
109{
110 int target_cpu, err;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400111 struct padata_parallel_queue *queue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100112 struct parallel_data *pd;
113
114 rcu_read_lock_bh();
115
116 pd = rcu_dereference(pinst->pd);
117
Steffen Klassert83f619f2010-07-07 15:32:02 +0200118 err = -EINVAL;
Steffen Klassert74247132010-07-20 08:51:25 +0200119 if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID)
Steffen Klassert16295be2010-01-06 19:47:10 +1100120 goto out;
121
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400122 if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu))
Steffen Klassert16295be2010-01-06 19:47:10 +1100123 goto out;
124
125 err = -EBUSY;
126 if ((pinst->flags & PADATA_RESET))
127 goto out;
128
129 if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM)
130 goto out;
131
Steffen Klassert83f619f2010-07-07 15:32:02 +0200132 err = 0;
Steffen Klassert16295be2010-01-06 19:47:10 +1100133 atomic_inc(&pd->refcnt);
134 padata->pd = pd;
135 padata->cb_cpu = cb_cpu;
136
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100137 target_cpu = padata_cpu_hash(pd);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400138 queue = per_cpu_ptr(pd->pqueue, target_cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100139
140 spin_lock(&queue->parallel.lock);
141 list_add_tail(&padata->list, &queue->parallel.list);
142 spin_unlock(&queue->parallel.lock);
143
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400144 queue_work_on(target_cpu, pinst->wq, &queue->work);
Steffen Klassert16295be2010-01-06 19:47:10 +1100145
146out:
147 rcu_read_unlock_bh();
148
149 return err;
150}
151EXPORT_SYMBOL(padata_do_parallel);
152
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000153/*
154 * padata_get_next - Get the next object that needs serialization.
155 *
156 * Return values are:
157 *
158 * A pointer to the control struct of the next object that needs
159 * serialization, if present in one of the percpu reorder queues.
160 *
161 * NULL, if all percpu reorder queues are empty.
162 *
163 * -EINPROGRESS, if the next object that needs serialization will
164 * be parallel processed by another cpu and is not yet present in
165 * the cpu's reorder queue.
166 *
167 * -ENODATA, if this cpu has to do the parallel processing for
168 * the next object.
169 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100170static struct padata_priv *padata_get_next(struct parallel_data *pd)
171{
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200172 int cpu, num_cpus;
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100173 unsigned int next_nr, next_index;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400174 struct padata_parallel_queue *queue, *next_queue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100175 struct padata_priv *padata;
176 struct padata_list *reorder;
177
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400178 num_cpus = cpumask_weight(pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100179
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200180 /*
181 * Calculate the percpu reorder queue and the sequence
182 * number of the next object.
183 */
184 next_nr = pd->processed;
185 next_index = next_nr % num_cpus;
186 cpu = padata_index_to_cpu(pd, next_index);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400187 next_queue = per_cpu_ptr(pd->pqueue, cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100188
Steffen Klassert16295be2010-01-06 19:47:10 +1100189 padata = NULL;
190
Steffen Klassert16295be2010-01-06 19:47:10 +1100191 reorder = &next_queue->reorder;
192
193 if (!list_empty(&reorder->list)) {
194 padata = list_entry(reorder->list.next,
195 struct padata_priv, list);
196
Steffen Klassert16295be2010-01-06 19:47:10 +1100197 spin_lock(&reorder->lock);
198 list_del_init(&padata->list);
199 atomic_dec(&pd->reorder_objects);
200 spin_unlock(&reorder->lock);
201
Steffen Klassert5f1a8c12010-07-07 15:32:39 +0200202 pd->processed++;
Steffen Klassert16295be2010-01-06 19:47:10 +1100203
204 goto out;
205 }
206
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400207 queue = per_cpu_ptr(pd->pqueue, smp_processor_id());
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000208 if (queue->cpu_index == next_queue->cpu_index) {
Steffen Klassert16295be2010-01-06 19:47:10 +1100209 padata = ERR_PTR(-ENODATA);
210 goto out;
211 }
212
213 padata = ERR_PTR(-EINPROGRESS);
214out:
215 return padata;
216}
217
218static void padata_reorder(struct parallel_data *pd)
219{
Steffen Klassert30478172012-03-09 07:20:12 +0100220 int cb_cpu;
Steffen Klassert16295be2010-01-06 19:47:10 +1100221 struct padata_priv *padata;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400222 struct padata_serial_queue *squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100223 struct padata_instance *pinst = pd->pinst;
224
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000225 /*
226 * We need to ensure that only one cpu can work on dequeueing of
227 * the reorder queue the time. Calculating in which percpu reorder
228 * queue the next object will arrive takes some time. A spinlock
229 * would be highly contended. Also it is not clear in which order
230 * the objects arrive to the reorder queues. So a cpu could wait to
231 * get the lock just to notice that there is nothing to do at the
232 * moment. Therefore we use a trylock and let the holder of the lock
233 * care for all the objects enqueued during the holdtime of the lock.
234 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100235 if (!spin_trylock_bh(&pd->lock))
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000236 return;
Steffen Klassert16295be2010-01-06 19:47:10 +1100237
238 while (1) {
239 padata = padata_get_next(pd);
240
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000241 /*
242 * All reorder queues are empty, or the next object that needs
243 * serialization is parallel processed by another cpu and is
244 * still on it's way to the cpu's reorder queue, nothing to
245 * do for now.
246 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100247 if (!padata || PTR_ERR(padata) == -EINPROGRESS)
248 break;
249
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000250 /*
251 * This cpu has to do the parallel processing of the next
252 * object. It's waiting in the cpu's parallelization queue,
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300253 * so exit immediately.
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000254 */
Steffen Klassert16295be2010-01-06 19:47:10 +1100255 if (PTR_ERR(padata) == -ENODATA) {
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000256 del_timer(&pd->timer);
Steffen Klassert16295be2010-01-06 19:47:10 +1100257 spin_unlock_bh(&pd->lock);
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000258 return;
Steffen Klassert16295be2010-01-06 19:47:10 +1100259 }
260
Steffen Klassert30478172012-03-09 07:20:12 +0100261 cb_cpu = padata->cb_cpu;
262 squeue = per_cpu_ptr(pd->squeue, cb_cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100263
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400264 spin_lock(&squeue->serial.lock);
265 list_add_tail(&padata->list, &squeue->serial.list);
266 spin_unlock(&squeue->serial.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100267
Steffen Klassert30478172012-03-09 07:20:12 +0100268 queue_work_on(cb_cpu, pinst->wq, &squeue->work);
Steffen Klassert16295be2010-01-06 19:47:10 +1100269 }
270
271 spin_unlock_bh(&pd->lock);
272
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000273 /*
274 * The next object that needs serialization might have arrived to
275 * the reorder queues in the meantime, we will be called again
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300276 * from the timer function if no one else cares for it.
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000277 */
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000278 if (atomic_read(&pd->reorder_objects)
279 && !(pinst->flags & PADATA_RESET))
280 mod_timer(&pd->timer, jiffies + HZ);
281 else
282 del_timer(&pd->timer);
Steffen Klassert16295be2010-01-06 19:47:10 +1100283
Steffen Klassert16295be2010-01-06 19:47:10 +1100284 return;
285}
286
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000287static void padata_reorder_timer(unsigned long arg)
288{
289 struct parallel_data *pd = (struct parallel_data *)arg;
290
291 padata_reorder(pd);
292}
293
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400294static void padata_serial_worker(struct work_struct *serial_work)
Steffen Klassert16295be2010-01-06 19:47:10 +1100295{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400296 struct padata_serial_queue *squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100297 struct parallel_data *pd;
298 LIST_HEAD(local_list);
299
300 local_bh_disable();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400301 squeue = container_of(serial_work, struct padata_serial_queue, work);
302 pd = squeue->pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100303
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400304 spin_lock(&squeue->serial.lock);
305 list_replace_init(&squeue->serial.list, &local_list);
306 spin_unlock(&squeue->serial.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100307
308 while (!list_empty(&local_list)) {
309 struct padata_priv *padata;
310
311 padata = list_entry(local_list.next,
312 struct padata_priv, list);
313
314 list_del_init(&padata->list);
315
316 padata->serial(padata);
317 atomic_dec(&pd->refcnt);
318 }
319 local_bh_enable();
320}
321
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000322/**
Steffen Klassert16295be2010-01-06 19:47:10 +1100323 * padata_do_serial - padata serialization function
324 *
325 * @padata: object to be serialized.
326 *
327 * padata_do_serial must be called for every parallelized object.
328 * The serialization callback function will run with BHs off.
329 */
330void padata_do_serial(struct padata_priv *padata)
331{
332 int cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400333 struct padata_parallel_queue *pqueue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100334 struct parallel_data *pd;
335
336 pd = padata->pd;
337
338 cpu = get_cpu();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400339 pqueue = per_cpu_ptr(pd->pqueue, cpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100340
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400341 spin_lock(&pqueue->reorder.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100342 atomic_inc(&pd->reorder_objects);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400343 list_add_tail(&padata->list, &pqueue->reorder.list);
344 spin_unlock(&pqueue->reorder.lock);
Steffen Klassert16295be2010-01-06 19:47:10 +1100345
346 put_cpu();
347
348 padata_reorder(pd);
349}
350EXPORT_SYMBOL(padata_do_serial);
351
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400352static int padata_setup_cpumasks(struct parallel_data *pd,
353 const struct cpumask *pcpumask,
354 const struct cpumask *cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100355{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400356 if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL))
357 return -ENOMEM;
358
Steffen Klassert13614e02012-03-28 08:43:21 +0200359 cpumask_and(pd->cpumask.pcpu, pcpumask, cpu_online_mask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400360 if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) {
361 free_cpumask_var(pd->cpumask.cbcpu);
362 return -ENOMEM;
363 }
364
Steffen Klassert13614e02012-03-28 08:43:21 +0200365 cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_online_mask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400366 return 0;
367}
368
369static void __padata_list_init(struct padata_list *pd_list)
370{
371 INIT_LIST_HEAD(&pd_list->list);
372 spin_lock_init(&pd_list->lock);
373}
374
375/* Initialize all percpu queues used by serial workers */
376static void padata_init_squeues(struct parallel_data *pd)
377{
378 int cpu;
379 struct padata_serial_queue *squeue;
380
381 for_each_cpu(cpu, pd->cpumask.cbcpu) {
382 squeue = per_cpu_ptr(pd->squeue, cpu);
383 squeue->pd = pd;
384 __padata_list_init(&squeue->serial);
385 INIT_WORK(&squeue->work, padata_serial_worker);
386 }
387}
388
389/* Initialize all percpu queues used by parallel workers */
390static void padata_init_pqueues(struct parallel_data *pd)
391{
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100392 int cpu_index, cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400393 struct padata_parallel_queue *pqueue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100394
395 cpu_index = 0;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400396 for_each_cpu(cpu, pd->cpumask.pcpu) {
397 pqueue = per_cpu_ptr(pd->pqueue, cpu);
398 pqueue->pd = pd;
399 pqueue->cpu_index = cpu_index;
Steffen Klassertfad3a902010-07-20 08:48:34 +0200400 cpu_index++;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400401
402 __padata_list_init(&pqueue->reorder);
403 __padata_list_init(&pqueue->parallel);
404 INIT_WORK(&pqueue->work, padata_parallel_worker);
405 atomic_set(&pqueue->num_obj, 0);
406 }
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400407}
408
409/* Allocate and initialize the internal cpumask dependend resources. */
410static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
411 const struct cpumask *pcpumask,
412 const struct cpumask *cbcpumask)
413{
414 struct parallel_data *pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100415
416 pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL);
417 if (!pd)
418 goto err;
419
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400420 pd->pqueue = alloc_percpu(struct padata_parallel_queue);
421 if (!pd->pqueue)
Steffen Klassert16295be2010-01-06 19:47:10 +1100422 goto err_free_pd;
423
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400424 pd->squeue = alloc_percpu(struct padata_serial_queue);
425 if (!pd->squeue)
426 goto err_free_pqueue;
427 if (padata_setup_cpumasks(pd, pcpumask, cbcpumask) < 0)
428 goto err_free_squeue;
Steffen Klassert16295be2010-01-06 19:47:10 +1100429
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400430 padata_init_pqueues(pd);
431 padata_init_squeues(pd);
Steffen Klassertd46a5ac2010-05-19 13:43:14 +1000432 setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd);
Steffen Klassert2dc9b5d2012-03-09 07:20:49 +0100433 pd->seq_nr = 0;
Steffen Klassert16295be2010-01-06 19:47:10 +1100434 atomic_set(&pd->reorder_objects, 0);
435 atomic_set(&pd->refcnt, 0);
436 pd->pinst = pinst;
437 spin_lock_init(&pd->lock);
438
439 return pd;
440
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400441err_free_squeue:
442 free_percpu(pd->squeue);
443err_free_pqueue:
444 free_percpu(pd->pqueue);
Steffen Klassert16295be2010-01-06 19:47:10 +1100445err_free_pd:
446 kfree(pd);
447err:
448 return NULL;
449}
450
451static void padata_free_pd(struct parallel_data *pd)
452{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400453 free_cpumask_var(pd->cpumask.pcpu);
454 free_cpumask_var(pd->cpumask.cbcpu);
455 free_percpu(pd->pqueue);
456 free_percpu(pd->squeue);
Steffen Klassert16295be2010-01-06 19:47:10 +1100457 kfree(pd);
458}
459
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000460/* Flush all objects out of the padata queues. */
Steffen Klassert2b73b072010-05-19 13:43:46 +1000461static void padata_flush_queues(struct parallel_data *pd)
462{
463 int cpu;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400464 struct padata_parallel_queue *pqueue;
465 struct padata_serial_queue *squeue;
Steffen Klassert2b73b072010-05-19 13:43:46 +1000466
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400467 for_each_cpu(cpu, pd->cpumask.pcpu) {
468 pqueue = per_cpu_ptr(pd->pqueue, cpu);
469 flush_work(&pqueue->work);
Steffen Klassert2b73b072010-05-19 13:43:46 +1000470 }
471
472 del_timer_sync(&pd->timer);
473
474 if (atomic_read(&pd->reorder_objects))
475 padata_reorder(pd);
476
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400477 for_each_cpu(cpu, pd->cpumask.cbcpu) {
478 squeue = per_cpu_ptr(pd->squeue, cpu);
479 flush_work(&squeue->work);
Steffen Klassert2b73b072010-05-19 13:43:46 +1000480 }
481
482 BUG_ON(atomic_read(&pd->refcnt) != 0);
483}
484
Steffen Klassert4c879172010-07-07 15:30:10 +0200485static void __padata_start(struct padata_instance *pinst)
486{
487 pinst->flags |= PADATA_INIT;
488}
489
Steffen Klassertee836552010-07-07 15:30:47 +0200490static void __padata_stop(struct padata_instance *pinst)
491{
492 if (!(pinst->flags & PADATA_INIT))
493 return;
494
495 pinst->flags &= ~PADATA_INIT;
496
497 synchronize_rcu();
498
499 get_online_cpus();
500 padata_flush_queues(pinst->pd);
501 put_online_cpus();
502}
503
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300504/* Replace the internal control structure with a new one. */
Steffen Klassert16295be2010-01-06 19:47:10 +1100505static void padata_replace(struct padata_instance *pinst,
506 struct parallel_data *pd_new)
507{
508 struct parallel_data *pd_old = pinst->pd;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400509 int notification_mask = 0;
Steffen Klassert16295be2010-01-06 19:47:10 +1100510
511 pinst->flags |= PADATA_RESET;
512
513 rcu_assign_pointer(pinst->pd, pd_new);
514
515 synchronize_rcu();
516
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400517 if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu))
518 notification_mask |= PADATA_CPU_PARALLEL;
519 if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu))
520 notification_mask |= PADATA_CPU_SERIAL;
Steffen Klassert16295be2010-01-06 19:47:10 +1100521
Steffen Klassert16295be2010-01-06 19:47:10 +1100522 padata_flush_queues(pd_old);
523 padata_free_pd(pd_old);
524
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400525 if (notification_mask)
526 blocking_notifier_call_chain(&pinst->cpumask_change_notifier,
Steffen Klassertc6356962010-07-27 07:15:50 +0200527 notification_mask,
528 &pd_new->cpumask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400529
Steffen Klassert16295be2010-01-06 19:47:10 +1100530 pinst->flags &= ~PADATA_RESET;
531}
532
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000533/**
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400534 * padata_register_cpumask_notifier - Registers a notifier that will be called
535 * if either pcpu or cbcpu or both cpumasks change.
Steffen Klassert16295be2010-01-06 19:47:10 +1100536 *
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400537 * @pinst: A poineter to padata instance
538 * @nblock: A pointer to notifier block.
Steffen Klassert16295be2010-01-06 19:47:10 +1100539 */
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400540int padata_register_cpumask_notifier(struct padata_instance *pinst,
541 struct notifier_block *nblock)
Steffen Klassert16295be2010-01-06 19:47:10 +1100542{
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400543 return blocking_notifier_chain_register(&pinst->cpumask_change_notifier,
544 nblock);
545}
546EXPORT_SYMBOL(padata_register_cpumask_notifier);
Steffen Klassert16295be2010-01-06 19:47:10 +1100547
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400548/**
549 * padata_unregister_cpumask_notifier - Unregisters cpumask notifier
550 * registered earlier using padata_register_cpumask_notifier
551 *
552 * @pinst: A pointer to data instance.
553 * @nlock: A pointer to notifier block.
554 */
555int padata_unregister_cpumask_notifier(struct padata_instance *pinst,
556 struct notifier_block *nblock)
557{
558 return blocking_notifier_chain_unregister(
559 &pinst->cpumask_change_notifier,
560 nblock);
561}
562EXPORT_SYMBOL(padata_unregister_cpumask_notifier);
Steffen Klassert16295be2010-01-06 19:47:10 +1100563
Steffen Klassert6751fb32010-04-29 14:42:30 +0200564
Steffen Klassert33e54452010-07-07 15:31:26 +0200565/* If cpumask contains no active cpu, we mark the instance as invalid. */
566static bool padata_validate_cpumask(struct padata_instance *pinst,
567 const struct cpumask *cpumask)
568{
Steffen Klassert13614e02012-03-28 08:43:21 +0200569 if (!cpumask_intersects(cpumask, cpu_online_mask)) {
Steffen Klassert33e54452010-07-07 15:31:26 +0200570 pinst->flags |= PADATA_INVALID;
571 return false;
Steffen Klassert16295be2010-01-06 19:47:10 +1100572 }
573
Steffen Klassert33e54452010-07-07 15:31:26 +0200574 pinst->flags &= ~PADATA_INVALID;
575 return true;
576}
577
Steffen Klassert65ff5772010-07-27 07:15:06 +0200578static int __padata_set_cpumasks(struct padata_instance *pinst,
579 cpumask_var_t pcpumask,
580 cpumask_var_t cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100581{
Steffen Klassert33e54452010-07-07 15:31:26 +0200582 int valid;
Steffen Klassert65ff5772010-07-27 07:15:06 +0200583 struct parallel_data *pd;
Steffen Klassert16295be2010-01-06 19:47:10 +1100584
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400585 valid = padata_validate_cpumask(pinst, pcpumask);
586 if (!valid) {
587 __padata_stop(pinst);
588 goto out_replace;
589 }
590
591 valid = padata_validate_cpumask(pinst, cbcpumask);
Steffen Klassertb89661d2010-07-20 08:49:20 +0200592 if (!valid)
Steffen Klassert33e54452010-07-07 15:31:26 +0200593 __padata_stop(pinst);
Steffen Klassert33e54452010-07-07 15:31:26 +0200594
Steffen Klassertb89661d2010-07-20 08:49:20 +0200595out_replace:
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400596 pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
Steffen Klassert65ff5772010-07-27 07:15:06 +0200597 if (!pd)
598 return -ENOMEM;
Steffen Klassert16295be2010-01-06 19:47:10 +1100599
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400600 cpumask_copy(pinst->cpumask.pcpu, pcpumask);
601 cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
Steffen Klassert16295be2010-01-06 19:47:10 +1100602
603 padata_replace(pinst, pd);
604
Steffen Klassert33e54452010-07-07 15:31:26 +0200605 if (valid)
606 __padata_start(pinst);
607
Steffen Klassert65ff5772010-07-27 07:15:06 +0200608 return 0;
609}
610
611/**
612 * padata_set_cpumasks - Set both parallel and serial cpumasks. The first
613 * one is used by parallel workers and the second one
614 * by the wokers doing serialization.
615 *
616 * @pinst: padata instance
617 * @pcpumask: the cpumask to use for parallel workers
618 * @cbcpumask: the cpumsak to use for serial workers
619 */
620int padata_set_cpumasks(struct padata_instance *pinst, cpumask_var_t pcpumask,
621 cpumask_var_t cbcpumask)
622{
623 int err;
624
625 mutex_lock(&pinst->lock);
626 get_online_cpus();
627
628 err = __padata_set_cpumasks(pinst, pcpumask, cbcpumask);
629
Steffen Klassert6751fb32010-04-29 14:42:30 +0200630 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100631 mutex_unlock(&pinst->lock);
632
633 return err;
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400634
Steffen Klassert16295be2010-01-06 19:47:10 +1100635}
Steffen Klassert65ff5772010-07-27 07:15:06 +0200636EXPORT_SYMBOL(padata_set_cpumasks);
637
638/**
639 * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value
640 * equivalent to @cpumask.
641 *
642 * @pinst: padata instance
643 * @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding
644 * to parallel and serial cpumasks respectively.
645 * @cpumask: the cpumask to use
646 */
647int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
648 cpumask_var_t cpumask)
649{
650 struct cpumask *serial_mask, *parallel_mask;
651 int err = -EINVAL;
652
653 mutex_lock(&pinst->lock);
654 get_online_cpus();
655
656 switch (cpumask_type) {
657 case PADATA_CPU_PARALLEL:
658 serial_mask = pinst->cpumask.cbcpu;
659 parallel_mask = cpumask;
660 break;
661 case PADATA_CPU_SERIAL:
662 parallel_mask = pinst->cpumask.pcpu;
663 serial_mask = cpumask;
664 break;
665 default:
666 goto out;
667 }
668
669 err = __padata_set_cpumasks(pinst, parallel_mask, serial_mask);
670
Steffen Klassert16295be2010-01-06 19:47:10 +1100671out:
672 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100673 mutex_unlock(&pinst->lock);
674
675 return err;
676}
677EXPORT_SYMBOL(padata_set_cpumask);
678
679static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
680{
681 struct parallel_data *pd;
682
Steffen Klassert13614e02012-03-28 08:43:21 +0200683 if (cpumask_test_cpu(cpu, cpu_online_mask)) {
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400684 pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
685 pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100686 if (!pd)
687 return -ENOMEM;
688
689 padata_replace(pinst, pd);
Steffen Klassert33e54452010-07-07 15:31:26 +0200690
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400691 if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) &&
692 padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
Steffen Klassert33e54452010-07-07 15:31:26 +0200693 __padata_start(pinst);
Steffen Klassert16295be2010-01-06 19:47:10 +1100694 }
695
696 return 0;
697}
698
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400699 /**
700 * padata_add_cpu - add a cpu to one or both(parallel and serial)
701 * padata cpumasks.
Steffen Klassert16295be2010-01-06 19:47:10 +1100702 *
703 * @pinst: padata instance
704 * @cpu: cpu to add
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400705 * @mask: bitmask of flags specifying to which cpumask @cpu shuld be added.
706 * The @mask may be any combination of the following flags:
707 * PADATA_CPU_SERIAL - serial cpumask
708 * PADATA_CPU_PARALLEL - parallel cpumask
Steffen Klassert16295be2010-01-06 19:47:10 +1100709 */
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400710
711int padata_add_cpu(struct padata_instance *pinst, int cpu, int mask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100712{
713 int err;
714
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400715 if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL)))
716 return -EINVAL;
717
Steffen Klassert16295be2010-01-06 19:47:10 +1100718 mutex_lock(&pinst->lock);
719
Steffen Klassert6751fb32010-04-29 14:42:30 +0200720 get_online_cpus();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400721 if (mask & PADATA_CPU_SERIAL)
722 cpumask_set_cpu(cpu, pinst->cpumask.cbcpu);
723 if (mask & PADATA_CPU_PARALLEL)
724 cpumask_set_cpu(cpu, pinst->cpumask.pcpu);
725
Steffen Klassert16295be2010-01-06 19:47:10 +1100726 err = __padata_add_cpu(pinst, cpu);
Steffen Klassert6751fb32010-04-29 14:42:30 +0200727 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100728
729 mutex_unlock(&pinst->lock);
730
731 return err;
732}
733EXPORT_SYMBOL(padata_add_cpu);
734
735static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
736{
Steffen Klassert33e54452010-07-07 15:31:26 +0200737 struct parallel_data *pd = NULL;
Steffen Klassert16295be2010-01-06 19:47:10 +1100738
739 if (cpumask_test_cpu(cpu, cpu_online_mask)) {
Steffen Klassert33e54452010-07-07 15:31:26 +0200740
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400741 if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) ||
Steffen Klassertb89661d2010-07-20 08:49:20 +0200742 !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
Steffen Klassert33e54452010-07-07 15:31:26 +0200743 __padata_stop(pinst);
Steffen Klassert33e54452010-07-07 15:31:26 +0200744
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400745 pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
746 pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100747 if (!pd)
748 return -ENOMEM;
749
750 padata_replace(pinst, pd);
Steffen Klassert96120902012-03-28 08:44:07 +0200751
752 cpumask_clear_cpu(cpu, pd->cpumask.cbcpu);
753 cpumask_clear_cpu(cpu, pd->cpumask.pcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +1100754 }
755
756 return 0;
757}
758
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400759 /**
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300760 * padata_remove_cpu - remove a cpu from the one or both(serial and parallel)
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400761 * padata cpumasks.
Steffen Klassert16295be2010-01-06 19:47:10 +1100762 *
763 * @pinst: padata instance
764 * @cpu: cpu to remove
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400765 * @mask: bitmask specifying from which cpumask @cpu should be removed
766 * The @mask may be any combination of the following flags:
767 * PADATA_CPU_SERIAL - serial cpumask
768 * PADATA_CPU_PARALLEL - parallel cpumask
Steffen Klassert16295be2010-01-06 19:47:10 +1100769 */
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400770int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask)
Steffen Klassert16295be2010-01-06 19:47:10 +1100771{
772 int err;
773
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400774 if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL)))
775 return -EINVAL;
776
Steffen Klassert16295be2010-01-06 19:47:10 +1100777 mutex_lock(&pinst->lock);
778
Steffen Klassert6751fb32010-04-29 14:42:30 +0200779 get_online_cpus();
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400780 if (mask & PADATA_CPU_SERIAL)
781 cpumask_clear_cpu(cpu, pinst->cpumask.cbcpu);
782 if (mask & PADATA_CPU_PARALLEL)
783 cpumask_clear_cpu(cpu, pinst->cpumask.pcpu);
784
Steffen Klassert16295be2010-01-06 19:47:10 +1100785 err = __padata_remove_cpu(pinst, cpu);
Steffen Klassert6751fb32010-04-29 14:42:30 +0200786 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +1100787
788 mutex_unlock(&pinst->lock);
789
790 return err;
791}
792EXPORT_SYMBOL(padata_remove_cpu);
793
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000794/**
Steffen Klassert16295be2010-01-06 19:47:10 +1100795 * padata_start - start the parallel processing
796 *
797 * @pinst: padata instance to start
798 */
Steffen Klassert4c879172010-07-07 15:30:10 +0200799int padata_start(struct padata_instance *pinst)
Steffen Klassert16295be2010-01-06 19:47:10 +1100800{
Steffen Klassert4c879172010-07-07 15:30:10 +0200801 int err = 0;
802
Steffen Klassert16295be2010-01-06 19:47:10 +1100803 mutex_lock(&pinst->lock);
Steffen Klassert4c879172010-07-07 15:30:10 +0200804
805 if (pinst->flags & PADATA_INVALID)
806 err =-EINVAL;
807
808 __padata_start(pinst);
809
Steffen Klassert16295be2010-01-06 19:47:10 +1100810 mutex_unlock(&pinst->lock);
Steffen Klassert4c879172010-07-07 15:30:10 +0200811
812 return err;
Steffen Klassert16295be2010-01-06 19:47:10 +1100813}
814EXPORT_SYMBOL(padata_start);
815
Steffen Klassert0198ffd2010-05-19 13:44:27 +1000816/**
Steffen Klassert16295be2010-01-06 19:47:10 +1100817 * padata_stop - stop the parallel processing
818 *
819 * @pinst: padata instance to stop
820 */
821void padata_stop(struct padata_instance *pinst)
822{
Steffen Klassert16295be2010-01-06 19:47:10 +1100823 mutex_lock(&pinst->lock);
Steffen Klassertee836552010-07-07 15:30:47 +0200824 __padata_stop(pinst);
Steffen Klassert16295be2010-01-06 19:47:10 +1100825 mutex_unlock(&pinst->lock);
826}
827EXPORT_SYMBOL(padata_stop);
828
Steffen Klasserte2cb2f12010-04-29 14:40:10 +0200829#ifdef CONFIG_HOTPLUG_CPU
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400830
831static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu)
832{
833 return cpumask_test_cpu(cpu, pinst->cpumask.pcpu) ||
834 cpumask_test_cpu(cpu, pinst->cpumask.cbcpu);
835}
836
837
Henrik Kretzschmar975d2602010-03-29 16:15:31 +0800838static int padata_cpu_callback(struct notifier_block *nfb,
839 unsigned long action, void *hcpu)
Steffen Klassert16295be2010-01-06 19:47:10 +1100840{
841 int err;
842 struct padata_instance *pinst;
843 int cpu = (unsigned long)hcpu;
844
845 pinst = container_of(nfb, struct padata_instance, cpu_notifier);
846
847 switch (action) {
848 case CPU_ONLINE:
849 case CPU_ONLINE_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:
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400861 if (!pinst_has_cpu(pinst, cpu))
Steffen Klassert16295be2010-01-06 19:47:10 +1100862 break;
863 mutex_lock(&pinst->lock);
864 err = __padata_remove_cpu(pinst, cpu);
865 mutex_unlock(&pinst->lock);
866 if (err)
Akinobu Mita80b51842010-05-26 14:43:32 -0700867 return notifier_from_errno(err);
Steffen Klassert16295be2010-01-06 19:47:10 +1100868 break;
869
870 case CPU_UP_CANCELED:
871 case CPU_UP_CANCELED_FROZEN:
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400872 if (!pinst_has_cpu(pinst, cpu))
Steffen Klassert16295be2010-01-06 19:47:10 +1100873 break;
874 mutex_lock(&pinst->lock);
875 __padata_remove_cpu(pinst, cpu);
876 mutex_unlock(&pinst->lock);
877
878 case CPU_DOWN_FAILED:
879 case CPU_DOWN_FAILED_FROZEN:
Dan Kruchinine15bacb2010-07-14 14:31:57 +0400880 if (!pinst_has_cpu(pinst, cpu))
Steffen Klassert16295be2010-01-06 19:47:10 +1100881 break;
882 mutex_lock(&pinst->lock);
883 __padata_add_cpu(pinst, cpu);
884 mutex_unlock(&pinst->lock);
885 }
886
887 return NOTIFY_OK;
888}
Steffen Klasserte2cb2f12010-04-29 14:40:10 +0200889#endif
Steffen Klassert16295be2010-01-06 19:47:10 +1100890
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400891static void __padata_free(struct padata_instance *pinst)
892{
893#ifdef CONFIG_HOTPLUG_CPU
894 unregister_hotcpu_notifier(&pinst->cpu_notifier);
895#endif
896
897 padata_stop(pinst);
898 padata_free_pd(pinst->pd);
899 free_cpumask_var(pinst->cpumask.pcpu);
900 free_cpumask_var(pinst->cpumask.cbcpu);
901 kfree(pinst);
902}
903
904#define kobj2pinst(_kobj) \
905 container_of(_kobj, struct padata_instance, kobj)
906#define attr2pentry(_attr) \
907 container_of(_attr, struct padata_sysfs_entry, attr)
908
909static void padata_sysfs_release(struct kobject *kobj)
910{
911 struct padata_instance *pinst = kobj2pinst(kobj);
912 __padata_free(pinst);
913}
914
915struct padata_sysfs_entry {
916 struct attribute attr;
917 ssize_t (*show)(struct padata_instance *, struct attribute *, char *);
918 ssize_t (*store)(struct padata_instance *, struct attribute *,
919 const char *, size_t);
920};
921
922static ssize_t show_cpumask(struct padata_instance *pinst,
923 struct attribute *attr, char *buf)
924{
925 struct cpumask *cpumask;
926 ssize_t len;
927
928 mutex_lock(&pinst->lock);
929 if (!strcmp(attr->name, "serial_cpumask"))
930 cpumask = pinst->cpumask.cbcpu;
931 else
932 cpumask = pinst->cpumask.pcpu;
933
934 len = bitmap_scnprintf(buf, PAGE_SIZE, cpumask_bits(cpumask),
935 nr_cpu_ids);
936 if (PAGE_SIZE - len < 2)
937 len = -EINVAL;
938 else
939 len += sprintf(buf + len, "\n");
940
941 mutex_unlock(&pinst->lock);
942 return len;
943}
944
945static ssize_t store_cpumask(struct padata_instance *pinst,
946 struct attribute *attr,
947 const char *buf, size_t count)
948{
949 cpumask_var_t new_cpumask;
950 ssize_t ret;
951 int mask_type;
952
953 if (!alloc_cpumask_var(&new_cpumask, GFP_KERNEL))
954 return -ENOMEM;
955
956 ret = bitmap_parse(buf, count, cpumask_bits(new_cpumask),
957 nr_cpumask_bits);
958 if (ret < 0)
959 goto out;
960
961 mask_type = !strcmp(attr->name, "serial_cpumask") ?
962 PADATA_CPU_SERIAL : PADATA_CPU_PARALLEL;
963 ret = padata_set_cpumask(pinst, mask_type, new_cpumask);
964 if (!ret)
965 ret = count;
966
967out:
968 free_cpumask_var(new_cpumask);
969 return ret;
970}
971
972#define PADATA_ATTR_RW(_name, _show_name, _store_name) \
973 static struct padata_sysfs_entry _name##_attr = \
974 __ATTR(_name, 0644, _show_name, _store_name)
975#define PADATA_ATTR_RO(_name, _show_name) \
976 static struct padata_sysfs_entry _name##_attr = \
977 __ATTR(_name, 0400, _show_name, NULL)
978
979PADATA_ATTR_RW(serial_cpumask, show_cpumask, store_cpumask);
980PADATA_ATTR_RW(parallel_cpumask, show_cpumask, store_cpumask);
981
982/*
983 * Padata sysfs provides the following objects:
984 * serial_cpumask [RW] - cpumask for serial workers
985 * parallel_cpumask [RW] - cpumask for parallel workers
Steffen Klassert16295be2010-01-06 19:47:10 +1100986 */
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400987static struct attribute *padata_default_attrs[] = {
988 &serial_cpumask_attr.attr,
989 &parallel_cpumask_attr.attr,
990 NULL,
991};
992
993static ssize_t padata_sysfs_show(struct kobject *kobj,
994 struct attribute *attr, char *buf)
Steffen Klassert16295be2010-01-06 19:47:10 +1100995{
Steffen Klassert16295be2010-01-06 19:47:10 +1100996 struct padata_instance *pinst;
Dan Kruchinin5e017dc2010-07-14 14:33:08 +0400997 struct padata_sysfs_entry *pentry;
998 ssize_t ret = -EIO;
999
1000 pinst = kobj2pinst(kobj);
1001 pentry = attr2pentry(attr);
1002 if (pentry->show)
1003 ret = pentry->show(pinst, attr, buf);
1004
1005 return ret;
1006}
1007
1008static ssize_t padata_sysfs_store(struct kobject *kobj, struct attribute *attr,
1009 const char *buf, size_t count)
1010{
1011 struct padata_instance *pinst;
1012 struct padata_sysfs_entry *pentry;
1013 ssize_t ret = -EIO;
1014
1015 pinst = kobj2pinst(kobj);
1016 pentry = attr2pentry(attr);
1017 if (pentry->show)
1018 ret = pentry->store(pinst, attr, buf, count);
1019
1020 return ret;
1021}
1022
1023static const struct sysfs_ops padata_sysfs_ops = {
1024 .show = padata_sysfs_show,
1025 .store = padata_sysfs_store,
1026};
1027
1028static struct kobj_type padata_attr_type = {
1029 .sysfs_ops = &padata_sysfs_ops,
1030 .default_attrs = padata_default_attrs,
1031 .release = padata_sysfs_release,
1032};
1033
Steffen Klassert16295be2010-01-06 19:47:10 +11001034/**
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001035 * padata_alloc_possible - Allocate and initialize padata instance.
1036 * Use the cpu_possible_mask for serial and
1037 * parallel workers.
Steffen Klassert16295be2010-01-06 19:47:10 +11001038 *
Steffen Klassert16295be2010-01-06 19:47:10 +11001039 * @wq: workqueue to use for the allocated padata instance
1040 */
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001041struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq)
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001042{
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001043 return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask);
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001044}
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001045EXPORT_SYMBOL(padata_alloc_possible);
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001046
1047/**
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001048 * padata_alloc - allocate and initialize a padata instance and specify
1049 * cpumasks for serial and parallel workers.
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001050 *
1051 * @wq: workqueue to use for the allocated padata instance
1052 * @pcpumask: cpumask that will be used for padata parallelization
1053 * @cbcpumask: cpumask that will be used for padata serialization
1054 */
Steffen Klasserte6cc1172010-07-27 07:14:28 +02001055struct padata_instance *padata_alloc(struct workqueue_struct *wq,
1056 const struct cpumask *pcpumask,
1057 const struct cpumask *cbcpumask)
Steffen Klassert16295be2010-01-06 19:47:10 +11001058{
1059 struct padata_instance *pinst;
Steffen Klassert33e54452010-07-07 15:31:26 +02001060 struct parallel_data *pd = NULL;
Steffen Klassert16295be2010-01-06 19:47:10 +11001061
1062 pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL);
1063 if (!pinst)
1064 goto err;
1065
Steffen Klassert6751fb32010-04-29 14:42:30 +02001066 get_online_cpus();
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001067 if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL))
Steffen Klassert16295be2010-01-06 19:47:10 +11001068 goto err_free_inst;
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001069 if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) {
1070 free_cpumask_var(pinst->cpumask.pcpu);
1071 goto err_free_inst;
Steffen Klassert33e54452010-07-07 15:31:26 +02001072 }
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001073 if (!padata_validate_cpumask(pinst, pcpumask) ||
1074 !padata_validate_cpumask(pinst, cbcpumask))
1075 goto err_free_masks;
Steffen Klassert16295be2010-01-06 19:47:10 +11001076
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001077 pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
1078 if (!pd)
1079 goto err_free_masks;
Steffen Klassert74781382010-03-04 13:30:22 +08001080
Steffen Klassert16295be2010-01-06 19:47:10 +11001081 rcu_assign_pointer(pinst->pd, pd);
1082
1083 pinst->wq = wq;
1084
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001085 cpumask_copy(pinst->cpumask.pcpu, pcpumask);
1086 cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
Steffen Klassert16295be2010-01-06 19:47:10 +11001087
1088 pinst->flags = 0;
1089
Steffen Klasserte2cb2f12010-04-29 14:40:10 +02001090#ifdef CONFIG_HOTPLUG_CPU
Steffen Klassert16295be2010-01-06 19:47:10 +11001091 pinst->cpu_notifier.notifier_call = padata_cpu_callback;
1092 pinst->cpu_notifier.priority = 0;
Steffen Klasserte2cb2f12010-04-29 14:40:10 +02001093 register_hotcpu_notifier(&pinst->cpu_notifier);
1094#endif
Steffen Klassert16295be2010-01-06 19:47:10 +11001095
Steffen Klassert6751fb32010-04-29 14:42:30 +02001096 put_online_cpus();
1097
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001098 BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier);
Dan Kruchinin5e017dc2010-07-14 14:33:08 +04001099 kobject_init(&pinst->kobj, &padata_attr_type);
Steffen Klassert16295be2010-01-06 19:47:10 +11001100 mutex_init(&pinst->lock);
1101
1102 return pinst;
1103
Dan Kruchinine15bacb2010-07-14 14:31:57 +04001104err_free_masks:
1105 free_cpumask_var(pinst->cpumask.pcpu);
1106 free_cpumask_var(pinst->cpumask.cbcpu);
Steffen Klassert16295be2010-01-06 19:47:10 +11001107err_free_inst:
1108 kfree(pinst);
Steffen Klassert6751fb32010-04-29 14:42:30 +02001109 put_online_cpus();
Steffen Klassert16295be2010-01-06 19:47:10 +11001110err:
1111 return NULL;
1112}
1113EXPORT_SYMBOL(padata_alloc);
1114
Steffen Klassert0198ffd2010-05-19 13:44:27 +10001115/**
Steffen Klassert16295be2010-01-06 19:47:10 +11001116 * padata_free - free a padata instance
1117 *
Steffen Klassert0198ffd2010-05-19 13:44:27 +10001118 * @padata_inst: padata instance to free
Steffen Klassert16295be2010-01-06 19:47:10 +11001119 */
1120void padata_free(struct padata_instance *pinst)
1121{
Dan Kruchinin5e017dc2010-07-14 14:33:08 +04001122 kobject_put(&pinst->kobj);
Steffen Klassert16295be2010-01-06 19:47:10 +11001123}
1124EXPORT_SYMBOL(padata_free);