blob: b245b9a9cc0bbdd6cdb3e74e6da90e009f6c515a (
plain)
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
|
/* Worker thread pool for slow items, such as filesystem lookups or mkdirs
*
* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*
* See Documentation/slow-work.txt
*/
#ifndef _LINUX_SLOW_WORK_H
#define _LINUX_SLOW_WORK_H
#ifdef CONFIG_SLOW_WORK
#include <linux/sysctl.h>
#include <linux/timer.h>
struct slow_work;
/*
* The operations used to support slow work items
*/
struct slow_work_ops {
/* owner */
struct module *owner;
/* get a ref on a work item
* - return 0 if successful, -ve if not
*/
int (*get_ref)(struct slow_work *work);
/* discard a ref to a work item */
void (*put_ref)(struct slow_work *work);
/* execute a work item */
void (*execute)(struct slow_work *work);
};
/*
* A slow work item
* - A reference is held on the parent object by the thread pool when it is
* queued
*/
struct slow_work {
struct module *owner; /* the owning module */
unsigned long flags;
#define SLOW_WORK_PENDING 0 /* item pending (further) execution */
#define SLOW_WORK_EXECUTING 1 /* item currently executing */
#define SLOW_WORK_ENQ_DEFERRED 2 /* item enqueue deferred */
#define SLOW_WORK_VERY_SLOW 3 /* item is very slow */
#define SLOW_WORK_CANCELLING 4 /* item is being cancelled, don't enqueue */
#define SLOW_WORK_DELAYED 5 /* item is struct delayed_slow_work with active timer */
const struct slow_work_ops *ops; /* operations table for this item */
struct list_head link; /* link in queue */
};
struct delayed_slow_work {
struct slow_work work;
struct timer_list timer;
};
/**
* slow_work_init - Initialise a slow work item
* @work: The work item to initialise
* @ops: The operations to use to handle the slow work item
*
* Initialise a slow work item.
*/
static inline void slow_work_init(struct slow_work *work,
const struct slow_work_ops *ops)
{
work->flags = 0;
work->ops = ops;
INIT_LIST_HEAD(&work->link);
}
/**
* slow_work_init - Initialise a delayed slow work item
* @work: The work item to initialise
* @ops: The operations to use to handle the slow work item
*
* Initialise a delayed slow work item.
*/
static inline void delayed_slow_work_init(struct delayed_slow_work *dwork,
const struct slow_work_ops *ops)
{
init_timer(&dwork->timer);
slow_work_init(&dwork->work, ops);
}
/**
* vslow_work_init - Initialise a very slow work item
* @work: The work item to initialise
* @ops: The operations to use to handle the slow work item
*
* Initialise a very slow work item. This item will be restricted such that
* only a certain number of the pool threads will be able to execute items of
* this type.
*/
static inline void vslow_work_init(struct slow_work *work,
const struct slow_work_ops *ops)
{
work->flags = 1 << SLOW_WORK_VERY_SLOW;
work->ops = ops;
INIT_LIST_HEAD(&work->link);
}
extern int slow_work_enqueue(struct slow_work *work);
extern void slow_work_cancel(struct slow_work *work);
extern int slow_work_register_user(struct module *owner);
extern void slow_work_unregister_user(struct module *owner);
extern int delayed_slow_work_enqueue(struct delayed_slow_work *dwork,
unsigned long delay);
static inline void delayed_slow_work_cancel(struct delayed_slow_work *dwork)
{
slow_work_cancel(&dwork->work);
}
#ifdef CONFIG_SYSCTL
extern ctl_table slow_work_sysctls[];
#endif
#endif /* CONFIG_SLOW_WORK */
#endif /* _LINUX_SLOW_WORK_H */
|
