1 /* delayacct.h - per-task delay accounting
3 * Copyright (C) Shailabh Nagar, IBM Corp. 2006
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
17 #ifndef _LINUX_DELAYACCT_H
18 #define _LINUX_DELAYACCT_H
20 #include <uapi/linux/taskstats.h>
21 #include <linux/sched.h>
22 #include <linux/slab.h>
25 * Per-task flags relevant to delay accounting
26 * maintained privately to avoid exhausting similar flags in sched.h:PF_*
27 * Used to set current->delays->flags
29 #define DELAYACCT_PF_SWAPIN 0x00000001 /* I am doing a swapin */
30 #define DELAYACCT_PF_BLKIO 0x00000002 /* I am waiting on IO */
32 #ifdef CONFIG_TASK_DELAY_ACCT
34 extern int delayacct_on; /* Delay accounting turned on/off */
35 extern struct kmem_cache *delayacct_cache;
36 extern void delayacct_init(void);
37 extern void __delayacct_tsk_init(struct task_struct *);
38 extern void __delayacct_tsk_exit(struct task_struct *);
39 extern void __delayacct_blkio_start(void);
40 extern void __delayacct_blkio_end(void);
41 extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *);
42 extern __u64 __delayacct_blkio_ticks(struct task_struct *);
43 extern void __delayacct_freepages_start(void);
44 extern void __delayacct_freepages_end(void);
46 static inline int delayacct_is_task_waiting_on_io(struct task_struct *p)
49 return (p->delays->flags & DELAYACCT_PF_BLKIO);
54 static inline void delayacct_set_flag(int flag)
57 current->delays->flags |= flag;
60 static inline void delayacct_clear_flag(int flag)
63 current->delays->flags &= ~flag;
66 static inline void delayacct_tsk_init(struct task_struct *tsk)
68 /* reinitialize in case parent's non-null pointer was dup'ed*/
71 __delayacct_tsk_init(tsk);
74 /* Free tsk->delays. Called from bad fork and __put_task_struct
75 * where there's no risk of tsk->delays being accessed elsewhere
77 static inline void delayacct_tsk_free(struct task_struct *tsk)
80 kmem_cache_free(delayacct_cache, tsk->delays);
84 static inline void delayacct_blkio_start(void)
86 delayacct_set_flag(DELAYACCT_PF_BLKIO);
88 __delayacct_blkio_start();
91 static inline void delayacct_blkio_end(void)
94 __delayacct_blkio_end();
95 delayacct_clear_flag(DELAYACCT_PF_BLKIO);
98 static inline int delayacct_add_tsk(struct taskstats *d,
99 struct task_struct *tsk)
101 if (!delayacct_on || !tsk->delays)
103 return __delayacct_add_tsk(d, tsk);
106 static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk)
109 return __delayacct_blkio_ticks(tsk);
113 static inline void delayacct_freepages_start(void)
116 __delayacct_freepages_start();
119 static inline void delayacct_freepages_end(void)
122 __delayacct_freepages_end();
126 static inline void delayacct_set_flag(int flag)
128 static inline void delayacct_clear_flag(int flag)
130 static inline void delayacct_init(void)
132 static inline void delayacct_tsk_init(struct task_struct *tsk)
134 static inline void delayacct_tsk_free(struct task_struct *tsk)
136 static inline void delayacct_blkio_start(void)
138 static inline void delayacct_blkio_end(void)
140 static inline int delayacct_add_tsk(struct taskstats *d,
141 struct task_struct *tsk)
143 static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk)
145 static inline int delayacct_is_task_waiting_on_io(struct task_struct *p)
147 static inline void delayacct_freepages_start(void)
149 static inline void delayacct_freepages_end(void)
152 #endif /* CONFIG_TASK_DELAY_ACCT */