1 /* 2 * Copyright (c) 1982, 1986, 1989 Regents of the University of California. 3 * All rights reserved. The Berkeley software License Agreement 4 * specifies the terms and conditions for redistribution. 5 * 6 * @(#)kern_acct.c 7.14 (Berkeley) 08/22/90 7 */ 8 9 #include "param.h" 10 #include "systm.h" 11 #include "time.h" 12 #include "proc.h" 13 #include "ioctl.h" 14 #include "termios.h" 15 #include "tty.h" 16 #include "user.h" 17 #include "vnode.h" 18 #include "mount.h" 19 #include "kernel.h" 20 #include "file.h" 21 #include "acct.h" 22 #include "uio.h" 23 #include "syslog.h" 24 25 /* 26 * Values associated with enabling and disabling accounting 27 */ 28 int acctsuspend = 2; /* stop accounting when < 2% free space left */ 29 int acctresume = 4; /* resume when free space risen to > 4% */ 30 struct timeval chk = { 15, 0 };/* frequency to check space for accounting */ 31 32 /* 33 * SHOULD REPLACE THIS WITH A DRIVER THAT CAN BE READ TO SIMPLIFY. 34 */ 35 struct vnode *acctp; 36 struct vnode *savacctp; 37 38 /* 39 * Perform process accounting functions. 40 */ 41 /* ARGSUSED */ 42 sysacct(p, uap, retval) 43 struct proc *p; 44 struct args { 45 char *fname; 46 } *uap; 47 int *retval; 48 { 49 register struct vnode *vp; 50 register struct nameidata *ndp = &u.u_nd; 51 extern int acctwatch(); 52 struct vnode *oacctp; 53 int error; 54 55 if (error = suser(u.u_cred, &u.u_acflag)) 56 return (error); 57 if (savacctp) { 58 acctp = savacctp; 59 savacctp = NULL; 60 } 61 if (uap->fname == NULL) { 62 if (vp = acctp) { 63 acctp = NULL; 64 vrele(vp); 65 untimeout(acctwatch, (caddr_t)&chk); 66 } 67 return (0); 68 } 69 ndp->ni_segflg = UIO_USERSPACE; 70 ndp->ni_dirp = uap->fname; 71 if (error = vn_open(ndp, FWRITE, 0644)) 72 return (error); 73 vp = ndp->ni_vp; 74 if (vp->v_type != VREG) { 75 vrele(vp); 76 return (EACCES); 77 } 78 oacctp = acctp; 79 acctp = vp; 80 if (oacctp) 81 vrele(oacctp); 82 acctwatch(&chk); 83 return (0); 84 } 85 86 /* 87 * Periodically check the file system to see if accounting 88 * should be turned on or off. 89 */ 90 acctwatch(resettime) 91 struct timeval *resettime; 92 { 93 struct statfs sb; 94 95 if (savacctp) { 96 (void)VFS_STATFS(savacctp->v_mount, &sb); 97 if (sb.f_bavail > acctresume * sb.f_blocks / 100) { 98 acctp = savacctp; 99 savacctp = NULL; 100 log(LOG_NOTICE, "Accounting resumed\n"); 101 return; 102 } 103 } 104 if (acctp == NULL) 105 return; 106 (void)VFS_STATFS(acctp->v_mount, &sb); 107 if (sb.f_bavail <= acctsuspend * sb.f_blocks / 100) { 108 savacctp = acctp; 109 acctp = NULL; 110 log(LOG_NOTICE, "Accounting suspended\n"); 111 } 112 timeout(acctwatch, (caddr_t)resettime, hzto(resettime)); 113 } 114 115 /* 116 * On exit, write a record on the accounting file. 117 */ 118 acct(p) 119 register struct proc *p; 120 { 121 register struct rusage *ru; 122 struct vnode *vp; 123 struct timeval t, ut, st; 124 int i, s; 125 struct acct acctbuf; 126 register struct acct *ap = &acctbuf; 127 128 if ((vp = acctp) == NULL) 129 return (0); 130 bcopy(p->p_comm, ap->ac_comm, sizeof(ap->ac_comm)); 131 ru = &u.u_ru; 132 s = splclock(); 133 ut = p->p_utime; 134 st = p->p_stime; 135 t = time; 136 splx(s); 137 ap->ac_utime = compress(ut.tv_sec, ut.tv_usec); 138 ap->ac_stime = compress(st.tv_sec, st.tv_usec); 139 timevalsub(&t, &u.u_start); 140 ap->ac_etime = compress(t.tv_sec, t.tv_usec); 141 ap->ac_btime = u.u_start.tv_sec; 142 ap->ac_uid = p->p_ruid; 143 ap->ac_gid = p->p_rgid; 144 t = st; 145 timevaladd(&t, &ut); 146 if (i = t.tv_sec * hz + t.tv_usec / tick) 147 ap->ac_mem = (ru->ru_ixrss+ru->ru_idrss+ru->ru_isrss) / i; 148 else 149 ap->ac_mem = 0; 150 ap->ac_io = compress(ru->ru_inblock + ru->ru_oublock, (long)0); 151 if (p->p_flag&SCTTY && p->p_session->s_ttyp) 152 ap->ac_tty = p->p_session->s_ttyp->t_dev; 153 else 154 ap->ac_tty = NODEV; 155 ap->ac_flag = u.u_acflag; 156 return (vn_rdwr(UIO_WRITE, vp, (caddr_t)ap, sizeof (acctbuf), 157 (off_t)0, UIO_SYSSPACE, IO_UNIT|IO_APPEND, u.u_cred, (int *)0)); 158 } 159 160 /* 161 * Produce a pseudo-floating point representation 162 * with 3 bits base-8 exponent, 13 bits fraction. 163 */ 164 compress(t, ut) 165 register long t; 166 long ut; 167 { 168 register exp = 0, round = 0; 169 170 t = t * AHZ; /* compiler will convert only this format to a shift */ 171 if (ut) 172 t += ut / (1000000 / AHZ); 173 while (t >= 8192) { 174 exp++; 175 round = t&04; 176 t >>= 3; 177 } 178 if (round) { 179 t++; 180 if (t >= 8192) { 181 t >>= 3; 182 exp++; 183 } 184 } 185 return ((exp<<13) + t); 186 } 187