include/linux/acct.h

   1 /*
   2  *  BSD Process Accounting for Linux - Definitions
   3  *
   4  *  Author: Marco van Wieringen (mvw@planets.elm.net)
   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 */