1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 *  BSD Process Accounting for Linux - Definitions
4 *
5 *  Author: Marco van Wieringen (mvw@planets.elm.net)
6 *
7 *  This header file contains the definitions needed to implement
8 *  BSD-style process accounting. The kernel accounting code and all
9 *  user-level programs that try to do something useful with the
10 *  process accounting log must include this file.
11 *
12 *  Copyright (C) 1995 - 1997 Marco van Wieringen - ELM Consultancy B.V.
13 *
14 */
15#ifndef _LINUX_ACCT_H
16#define _LINUX_ACCT_H
17
18#include <uapi/linux/acct.h>
19
20
21
22#ifdef CONFIG_BSD_PROCESS_ACCT
23struct pid_namespace;
24extern void acct_collect(long exitcode, int group_dead);
25extern void acct_process(void);
26extern void acct_exit_ns(struct pid_namespace *);
27#else
28#define acct_collect(x,y)	do { } while (0)
29#define acct_process()		do { } while (0)
30#define acct_exit_ns(ns)	do { } while (0)
31#endif
32
33/*
34 * ACCT_VERSION numbers as yet defined:
35 * 0: old format (until 2.6.7) with 16 bit uid/gid
36 * 1: extended variant (binary compatible on M68K)
37 * 2: extended variant (binary compatible on everything except M68K)
38 * 3: new binary incompatible format (64 bytes)
39 * 4: new binary incompatible format (128 bytes)
40 * 5: new binary incompatible format (128 bytes, second half)
41 *
42 */
43
44#undef ACCT_VERSION
45#undef AHZ
46
47#ifdef CONFIG_BSD_PROCESS_ACCT_V3
48#define ACCT_VERSION	3
49#define AHZ		100
50typedef struct acct_v3 acct_t;
51#else
52#ifdef CONFIG_M68K
53#define ACCT_VERSION	1
54#else
55#define ACCT_VERSION	2
56#endif
57#define AHZ		(USER_HZ)
58typedef struct acct acct_t;
59#endif
60
61#include <linux/jiffies.h>
62/*
63 * Yet another set of HZ to *HZ helper functions.
64 * See <linux/jiffies.h> for the original.
65 */
66
67static inline u32 jiffies_to_AHZ(unsigned long x)
68{
69#if (TICK_NSEC % (NSEC_PER_SEC / AHZ)) == 0
70# if HZ < AHZ
71	return x * (AHZ / HZ);
72# else
73	return x / (HZ / AHZ);
74# endif
75#else
76        u64 tmp = (u64)x * TICK_NSEC;
77        do_div(tmp, (NSEC_PER_SEC / AHZ));
78        return (long)tmp;
79#endif
80}
81
82static inline u64 nsec_to_AHZ(u64 x)
83{
84#if (NSEC_PER_SEC % AHZ) == 0
85	do_div(x, (NSEC_PER_SEC / AHZ));
86#elif (AHZ % 512) == 0
87	x *= AHZ/512;
88	do_div(x, (NSEC_PER_SEC / 512));
89#else
90	/*
91         * max relative error 5.7e-8 (1.8s per year) for AHZ <= 1024,
92         * overflow after 64.99 years.
93         * exact for AHZ=60, 72, 90, 120, 144, 180, 300, 600, 900, ...
94         */
95	x *= 9;
96	do_div(x, (unsigned long)((9ull * NSEC_PER_SEC + (AHZ/2))
97	                          / AHZ));
98#endif
99	return x;
100}
101
102#endif	/* _LINUX_ACCT_H */
103