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>
23 * Per-task flags relevant to delay accounting
24 * maintained privately to avoid exhausting similar flags in sched.h:PF_*
25 * Used to set current->delays->flags
27 #define DELAYACCT_PF_SWAPIN 0x00000001 /* I am doing a swapin */
28 #define DELAYACCT_PF_BLKIO 0x00000002 /* I am waiting on IO */
30 #ifdef CONFIG_TASK_DELAY_ACCT
31 struct task_delay_info {
33 unsigned int flags; /* Private per-task flags */
35 /* For each stat XXX, add following, aligned appropriately
37 * struct timespec XXX_start, XXX_end;
41 * Atomicity of updates to XXX_delay, XXX_count protected by
42 * single lock above (split into XXX_lock if contention is an issue).
46 * XXX_count is incremented on every XXX operation, the delay
47 * associated with the operation is added to XXX_delay.
48 * XXX_delay contains the accumulated delay time in nanoseconds.
50 u64 blkio_start; /* Shared by blkio, swapin */
51 u64 blkio_delay; /* wait for sync block io completion */
52 u64 swapin_delay; /* wait for swapin block io completion */
53 u32 blkio_count; /* total count of the number of sync block */
54 /* io operations performed */
55 u32 swapin_count; /* total count of the number of swapin block */
56 /* io operations performed */
59 u64 freepages_delay; /* wait for memory reclaim */
62 u64 thrashing_delay; /* wait for thrashing page */
64 u32 freepages_count; /* total count of memory reclaim */
65 u32 thrashing_count; /* total count of thrash waits */
69 #include <linux/sched.h>
70 #include <linux/slab.h>
72 #ifdef CONFIG_TASK_DELAY_ACCT
73 extern int delayacct_on; /* Delay accounting turned on/off */
74 extern struct kmem_cache *delayacct_cache;
75 extern void delayacct_init(void);
76 extern void __delayacct_tsk_init(struct task_struct *);
77 extern void __delayacct_tsk_exit(struct task_struct *);
78 extern void __delayacct_blkio_start(void);
79 extern void __delayacct_blkio_end(struct task_struct *);
80 extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *);
81 extern __u64 __delayacct_blkio_ticks(struct task_struct *);
82 extern void __delayacct_freepages_start(void);
83 extern void __delayacct_freepages_end(void);
84 extern void __delayacct_thrashing_start(void);
85 extern void __delayacct_thrashing_end(void);
87 static inline int delayacct_is_task_waiting_on_io(struct task_struct *p)
90 return (p->delays->flags & DELAYACCT_PF_BLKIO);
95 static inline void delayacct_set_flag(int flag)
98 current->delays->flags |= flag;
101 static inline void delayacct_clear_flag(int flag)
104 current->delays->flags &= ~flag;
107 static inline void delayacct_tsk_init(struct task_struct *tsk)
109 /* reinitialize in case parent's non-null pointer was dup'ed*/
112 __delayacct_tsk_init(tsk);
115 /* Free tsk->delays. Called from bad fork and __put_task_struct
116 * where there's no risk of tsk->delays being accessed elsewhere
118 static inline void delayacct_tsk_free(struct task_struct *tsk)
121 kmem_cache_free(delayacct_cache, tsk->delays);
125 static inline void delayacct_blkio_start(void)
127 delayacct_set_flag(DELAYACCT_PF_BLKIO);
129 __delayacct_blkio_start();
132 static inline void delayacct_blkio_end(struct task_struct *p)
135 __delayacct_blkio_end(p);
136 delayacct_clear_flag(DELAYACCT_PF_BLKIO);
139 static inline int delayacct_add_tsk(struct taskstats *d,
140 struct task_struct *tsk)
142 if (!delayacct_on || !tsk->delays)
144 return __delayacct_add_tsk(d, tsk);
147 static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk)
150 return __delayacct_blkio_ticks(tsk);
154 static inline void delayacct_freepages_start(void)
157 __delayacct_freepages_start();
160 static inline void delayacct_freepages_end(void)
163 __delayacct_freepages_end();
166 static inline void delayacct_thrashing_start(void)
169 __delayacct_thrashing_start();
172 static inline void delayacct_thrashing_end(void)
175 __delayacct_thrashing_end();
179 static inline void delayacct_set_flag(int flag)
181 static inline void delayacct_clear_flag(int flag)
183 static inline void delayacct_init(void)
185 static inline void delayacct_tsk_init(struct task_struct *tsk)
187 static inline void delayacct_tsk_free(struct task_struct *tsk)
189 static inline void delayacct_blkio_start(void)
191 static inline void delayacct_blkio_end(struct task_struct *p)
193 static inline int delayacct_add_tsk(struct taskstats *d,
194 struct task_struct *tsk)
196 static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk)
198 static inline int delayacct_is_task_waiting_on_io(struct task_struct *p)
200 static inline void delayacct_freepages_start(void)
202 static inline void delayacct_freepages_end(void)
204 static inline void delayacct_thrashing_start(void)
206 static inline void delayacct_thrashing_end(void)
209 #endif /* CONFIG_TASK_DELAY_ACCT */