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 7.12 (Berkeley) 06/28/90 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 "acct.h" 21 #include "uio.h" 22 #include "syslog.h" 23 24 /* 25 * Values associated with enabling and disabling accounting 26 */ 27 int acctsuspend = 2; /* stop accounting when < 2% free space left */ 28 int acctresume = 4; /* resume when free space risen to > 4% */ 29 struct timeval chk = { 15, 0 };/* frequency to check space for accounting */ 30 31 /* 32 * SHOULD REPLACE THIS WITH A DRIVER THAT CAN BE READ TO SIMPLIFY. 33 */ 34 struct vnode *acctp; 35 struct vnode *savacctp; 36 37 /* 38 * Perform process accounting functions. 39 */ 40 /* ARGSUSED */ 41 sysacct(p, uap, retval) 42 struct proc *p; 43 struct args { 44 char *fname; 45 } *uap; 46 int *retval; 47 { 48 register struct vnode *vp; 49 register struct nameidata *ndp = &u.u_nd; 50 extern int acctwatch(); 51 struct vnode *oacctp; 52 int error; 53 54 if (error = suser(u.u_cred, &u.u_acflag)) 55 return (error); 56 if (savacctp) { 57 acctp = savacctp; 58 savacctp = NULL; 59 } 60 if (uap->fname==NULL) { 61 if (vp = acctp) { 62 acctp = NULL; 63 vrele(vp); 64 untimeout(acctwatch, (caddr_t)&chk); 65 } 66 return (0); 67 } 68 ndp->ni_nameiop = LOOKUP | FOLLOW; 69 ndp->ni_segflg = UIO_USERSPACE; 70 ndp->ni_dirp = uap->fname; 71 if (error = namei(ndp)) 72 return (error); 73 vp = ndp->ni_vp; 74 if (vp->v_type != VREG) { 75 vrele(vp); 76 return (EACCES); 77 } 78 if (vp->v_mount->mnt_flag & MNT_RDONLY) { 79 vrele(vp); 80 return (EROFS); 81 } 82 oacctp = acctp; 83 acctp = vp; 84 if (oacctp) 85 vrele(oacctp); 86 acctwatch(&chk); 87 return (0); 88 } 89 90 /* 91 * Periodically check the file system to see if accounting 92 * should be turned on or off. 93 */ 94 acctwatch(resettime) 95 struct timeval *resettime; 96 { 97 struct statfs sb; 98 99 if (savacctp) { 100 (void)VFS_STATFS(savacctp->v_mount, &sb); 101 if (sb.f_bavail > acctresume * sb.f_blocks / 100) { 102 acctp = savacctp; 103 savacctp = NULL; 104 log(LOG_NOTICE, "Accounting resumed\n"); 105 return; 106 } 107 } 108 if (acctp == NULL) 109 return; 110 (void)VFS_STATFS(acctp->v_mount, &sb); 111 if (sb.f_bavail <= acctsuspend * sb.f_blocks / 100) { 112 savacctp = acctp; 113 acctp = NULL; 114 log(LOG_NOTICE, "Accounting suspended\n"); 115 } 116 timeout(acctwatch, (caddr_t)resettime, hzto(resettime)); 117 } 118 119 /* 120 * On exit, write a record on the accounting file. 121 */ 122 acct(p) 123 register struct proc *p; 124 { 125 register struct rusage *ru; 126 struct vnode *vp; 127 struct timeval t, ut, st; 128 int i, s; 129 struct acct acctbuf; 130 register struct acct *ap = &acctbuf; 131 132 if ((vp = acctp) == NULL) 133 return (0); 134 bcopy(p->p_comm, ap->ac_comm, sizeof(ap->ac_comm)); 135 ru = &u.u_ru; 136 s = splclock(); 137 ut = p->p_utime; 138 st = p->p_stime; 139 t = time; 140 splx(s); 141 ap->ac_utime = compress(ut.tv_sec, ut.tv_usec); 142 ap->ac_stime = compress(st.tv_sec, st.tv_usec); 143 timevalsub(&t, &u.u_start); 144 ap->ac_etime = compress(t.tv_sec, t.tv_usec); 145 ap->ac_btime = u.u_start.tv_sec; 146 ap->ac_uid = p->p_ruid; 147 ap->ac_gid = p->p_rgid; 148 t = st; 149 timevaladd(&t, &ut); 150 if (i = t.tv_sec * hz + t.tv_usec / tick) 151 ap->ac_mem = (ru->ru_ixrss+ru->ru_idrss+ru->ru_isrss) / i; 152 else 153 ap->ac_mem = 0; 154 ap->ac_mem >>= CLSIZELOG2; 155 ap->ac_io = compress(ru->ru_inblock + ru->ru_oublock, (long)0); 156 if (p->p_flag&SCTTY && p->p_session->s_ttyp) 157 ap->ac_tty = p->p_session->s_ttyp->t_dev; 158 else 159 ap->ac_tty = NODEV; 160 ap->ac_flag = u.u_acflag; 161 return (vn_rdwr(UIO_WRITE, vp, (caddr_t)ap, sizeof (acctbuf), 162 (off_t)0, UIO_SYSSPACE, IO_UNIT|IO_APPEND, u.u_cred, (int *)0)); 163 } 164 165 /* 166 * Produce a pseudo-floating point representation 167 * with 3 bits base-8 exponent, 13 bits fraction. 168 */ 169 compress(t, ut) 170 register long t; 171 long ut; 172 { 173 register exp = 0, round = 0; 174 175 t = t * AHZ; /* compiler will convert only this format to a shift */ 176 if (ut) 177 t += ut / (1000000 / AHZ); 178 while (t >= 8192) { 179 exp++; 180 round = t&04; 181 t >>= 3; 182 } 183 if (round) { 184 t++; 185 if (t >= 8192) { 186 t >>= 3; 187 exp++; 188 } 189 } 190 return ((exp<<13) + t); 191 } 192