aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/padata.h
blob: 23717eeaad23a59a71358a7dea78a0a91548eb45 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * padata.h - header for the padata parallelization interface
 *
 * Copyright (C) 2008, 2009 secunet Security Networks AG
 * Copyright (C) 2008, 2009 Steffen Klassert <steffen.klassert@secunet.com>
 */

#ifndef PADATA_H
#define PADATA_H

#include <linux/workqueue.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/notifier.h>
#include <linux/kobject.h>

#define PADATA_CPU_SERIAL   0x01
#define PADATA_CPU_PARALLEL 0x02

/**
 * struct padata_priv -  Embedded to the users data structure.
 *
 * @list: List entry, to attach to the padata lists.
 * @pd: Pointer to the internal control structure.
 * @cb_cpu: Callback cpu for serializatioon.
 * @cpu: Cpu for parallelization.
 * @seq_nr: Sequence number of the parallelized data object.
 * @info: Used to pass information from the parallel to the serial function.
 * @parallel: Parallel execution function.
 * @serial: Serial complete function.
 */
struct padata_priv {
	struct list_head	list;
	struct parallel_data	*pd;
	int			cb_cpu;
	int			cpu;
	unsigned int		seq_nr;
	int			info;
	void                    (*parallel)(struct padata_priv *padata);
	void                    (*serial)(struct padata_priv *padata);
};

/**
 * struct padata_list
 *
 * @list: List head.
 * @lock: List lock.
 */
struct padata_list {
	struct list_head        list;
	spinlock_t              lock;
};

/**
* struct padata_serial_queue - The percpu padata serial queue
*
* @serial: List to wait for serialization after reordering.
* @work: work struct for serialization.
* @pd: Backpointer to the internal control structure.
*/
struct padata_serial_queue {
       struct padata_list    serial;
       struct work_struct    work;
       struct parallel_data *pd;
};

/**
 * struct padata_parallel_queue - The percpu padata parallel queue
 *
 * @parallel: List to wait for parallelization.
 * @reorder: List to wait for reordering after parallel processing.
 * @serial: List to wait for serialization after reordering.
 * @pwork: work struct for parallelization.
 * @swork: work struct for serialization.
 * @work: work struct for parallelization.
 * @num_obj: Number of objects that are processed by this cpu.
 */
struct padata_parallel_queue {
       struct padata_list    parallel;
       struct padata_list    reorder;
       struct work_struct    work;
       atomic_t              num_obj;
};

/**
 * struct padata_cpumask - The cpumasks for the parallel/serial workers
 *
 * @pcpu: cpumask for the parallel workers.
 * @cbcpu: cpumask for the serial (callback) workers.
 */
struct padata_cpumask {
	cpumask_var_t	pcpu;
	cpumask_var_t	cbcpu;
};

/**
 * struct parallel_data - Internal control structure, covers everything
 * that depends on the cpumask in use.
 *
 * @pinst: padata instance.
 * @pqueue: percpu padata queues used for parallelization.
 * @squeue: percpu padata queues used for serialuzation.
 * @reorder_objects: Number of objects waiting in the reorder queues.
 * @refcnt: Number of objects holding a reference on this parallel_data.
 * @max_seq_nr:  Maximal used sequence number.
 * @processed: Number of already processed objects.
 * @cpu: Next CPU to be processed.
 * @cpumask: The cpumasks in use for parallel and serial workers.
 * @reorder_work: work struct for reordering.
 * @lock: Reorder lock.
 */
struct parallel_data {
	struct padata_instance		*pinst;
	struct padata_parallel_queue	__percpu *pqueue;
	struct padata_serial_queue	__percpu *squeue;
	atomic_t			reorder_objects;
	atomic_t			refcnt;
	atomic_t			seq_nr;
	unsigned int			processed;
	int				cpu;
	struct padata_cpumask		cpumask;
	struct work_struct		reorder_work;
	spinlock_t                      lock ____cacheline_aligned;
};

/**
 * struct padata_instance - The overall control structure.
 *
 * @cpu_notifier: cpu hotplug notifier.
 * @parallel_wq: The workqueue used for parallel work.
 * @serial_wq: The workqueue used for serial work.
 * @pd: The internal control structure.
 * @cpumask: User supplied cpumasks for parallel and serial works.
 * @cpumask_change_notifier: Notifiers chain for user-defined notify
 *            callbacks that will be called when either @pcpu or @cbcpu
 *            or both cpumasks change.
 * @kobj: padata instance kernel object.
 * @lock: padata instance lock.
 * @flags: padata flags.
 */
struct padata_instance {
	struct hlist_node		 node;
	struct workqueue_struct		*parallel_wq;
	struct workqueue_struct		*serial_wq;
	struct parallel_data		*pd;
	struct padata_cpumask		cpumask;
	struct blocking_notifier_head	 cpumask_change_notifier;
	struct kobject                   kobj;
	struct mutex			 lock;
	u8				 flags;
#define	PADATA_INIT	1
#define	PADATA_RESET	2
#define	PADATA_INVALID	4
};

extern struct padata_instance *padata_alloc_possible(const char *name);
extern void padata_free(struct padata_instance *pinst);
extern int padata_do_parallel(struct padata_instance *pinst,
			      struct padata_priv *padata, int *cb_cpu);
extern void padata_do_serial(struct padata_priv *padata);
extern int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
			      cpumask_var_t cpumask);
extern int padata_start(struct padata_instance *pinst);
extern void padata_stop(struct padata_instance *pinst);
extern int padata_register_cpumask_notifier(struct padata_instance *pinst,
					    struct notifier_block *nblock);
extern int padata_unregister_cpumask_notifier(struct padata_instance *pinst,
					      struct notifier_block *nblock);
#endif