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acct.h
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1 /*
2  * BSD Process Accounting for Linux - Definitions
3  *
4  * Author: Marco van Wieringen ([email protected])
5  *
6  * This header file contains the definitions needed to implement
7  * BSD-style process accounting. The kernel accounting code and all
8  * user-level programs that try to do something useful with the
9  * process accounting log must include this file.
10  *
11  * Copyright (C) 1995 - 1997 Marco van Wieringen - ELM Consultancy B.V.
12  *
13  */
14 #ifndef _LINUX_ACCT_H
15 #define _LINUX_ACCT_H
16 
17 #include <uapi/linux/acct.h>
18 
19 
20 
21 #ifdef CONFIG_BSD_PROCESS_ACCT
22 struct vfsmount;
23 struct super_block;
24 struct pacct_struct;
25 struct pid_namespace;
26 extern int acct_parm[]; /* for sysctl */
27 extern void acct_auto_close_mnt(struct vfsmount *m);
28 extern void acct_auto_close(struct super_block *sb);
29 extern void acct_collect(long exitcode, int group_dead);
30 extern void acct_process(void);
31 extern void acct_exit_ns(struct pid_namespace *);
32 #else
33 #define acct_auto_close_mnt(x) do { } while (0)
34 #define acct_auto_close(x) do { } while (0)
35 #define acct_collect(x,y) do { } while (0)
36 #define acct_process() do { } while (0)
37 #define acct_exit_ns(ns) do { } while (0)
38 #endif
39 
40 /*
41  * ACCT_VERSION numbers as yet defined:
42  * 0: old format (until 2.6.7) with 16 bit uid/gid
43  * 1: extended variant (binary compatible on M68K)
44  * 2: extended variant (binary compatible on everything except M68K)
45  * 3: new binary incompatible format (64 bytes)
46  * 4: new binary incompatible format (128 bytes)
47  * 5: new binary incompatible format (128 bytes, second half)
48  *
49  */
50 
51 #undef ACCT_VERSION
52 #undef AHZ
53 
54 #ifdef CONFIG_BSD_PROCESS_ACCT_V3
55 #define ACCT_VERSION 3
56 #define AHZ 100
57 typedef struct acct_v3 acct_t;
58 #else
59 #ifdef CONFIG_M68K
60 #define ACCT_VERSION 1
61 #else
62 #define ACCT_VERSION 2
63 #endif
64 #define AHZ (USER_HZ)
65 typedef struct acct acct_t;
66 #endif
67 
68 #include <linux/jiffies.h>
69 /*
70  * Yet another set of HZ to *HZ helper functions.
71  * See <linux/jiffies.h> for the original.
72  */
73 
74 static inline u32 jiffies_to_AHZ(unsigned long x)
75 {
76 #if (TICK_NSEC % (NSEC_PER_SEC / AHZ)) == 0
77 # if HZ < AHZ
78  return x * (AHZ / HZ);
79 # else
80  return x / (HZ / AHZ);
81 # endif
82 #else
83  u64 tmp = (u64)x * TICK_NSEC;
84  do_div(tmp, (NSEC_PER_SEC / AHZ));
85  return (long)tmp;
86 #endif
87 }
88 
89 static inline u64 nsec_to_AHZ(u64 x)
90 {
91 #if (NSEC_PER_SEC % AHZ) == 0
92  do_div(x, (NSEC_PER_SEC / AHZ));
93 #elif (AHZ % 512) == 0
94  x *= AHZ/512;
95  do_div(x, (NSEC_PER_SEC / 512));
96 #else
97  /*
98  * max relative error 5.7e-8 (1.8s per year) for AHZ <= 1024,
99  * overflow after 64.99 years.
100  * exact for AHZ=60, 72, 90, 120, 144, 180, 300, 600, 900, ...
101  */
102  x *= 9;
103  do_div(x, (unsigned long)((9ull * NSEC_PER_SEC + (AHZ/2))
104  / AHZ));
105 #endif
106  return x;
107 }
108 
109 #endif /* _LINUX_ACCT_H */