1 /*- 2 * Copyright (c) 1982, 1986, 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.proprietary.c% 6 * 7 * @(#)kern_acct.c 7.21 (Berkeley) 02/03/92 8 */ 9 10 #include "param.h" 11 #include "systm.h" 12 #include "namei.h" 13 #include "resourcevar.h" 14 #include "proc.h" 15 #include "ioctl.h" 16 #include "termios.h" 17 #include "tty.h" 18 #include "vnode.h" 19 #include "mount.h" 20 #include "kernel.h" 21 #include "file.h" 22 #include "acct.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 * Enable or disable process accounting. 40 * 41 * If a non-null filename is given, that file is used to store accounting 42 * records on process exit. If a null filename is given process accounting 43 * is suspended. If accounting is enabled, the system checks the amount 44 * of freespace on the filesystem at timeval intervals. If the amount of 45 * freespace is below acctsuspend percent, accounting is suspended. If 46 * accounting has been suspended, and freespace rises above acctresume, 47 * accounting is resumed. 48 */ 49 /* ARGSUSED */ 50 sysacct(p, uap, retval) 51 struct proc *p; 52 struct args { 53 char *fname; 54 } *uap; 55 int *retval; 56 { 57 register struct vnode *vp; 58 extern int acctwatch(); 59 struct vnode *oacctp; 60 int error; 61 struct nameidata nd; 62 63 if (error = suser(p->p_ucred, &p->p_acflag)) 64 return (error); 65 if (savacctp) { 66 acctp = savacctp; 67 savacctp = NULL; 68 } 69 if (uap->fname == NULL) { 70 if (vp = acctp) { 71 acctp = NULL; 72 error = vn_close(vp, FWRITE, p->p_ucred, p); 73 untimeout(acctwatch, (caddr_t)&chk); 74 } 75 return (error); 76 } 77 NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, uap->fname, p); 78 if (error = vn_open(&nd, FWRITE, 0644)) 79 return (error); 80 vp = nd.ni_vp; 81 VOP_UNLOCK(vp); 82 if (vp->v_type != VREG) { 83 (void) vn_close(vp, FWRITE, p->p_ucred, p); 84 return (EACCES); 85 } 86 oacctp = acctp; 87 acctp = vp; 88 if (oacctp) 89 error = vn_close(oacctp, FWRITE, p->p_ucred, p); 90 acctwatch(&chk); 91 return (error); 92 } 93 94 /* 95 * Periodically check the file system to see if accounting 96 * should be turned on or off. 97 */ 98 acctwatch(resettime) 99 struct timeval *resettime; 100 { 101 struct statfs sb; 102 103 if (savacctp) { 104 (void)VFS_STATFS(savacctp->v_mount, &sb, (struct proc *)0); 105 if (sb.f_bavail > acctresume * sb.f_blocks / 100) { 106 acctp = savacctp; 107 savacctp = NULL; 108 log(LOG_NOTICE, "Accounting resumed\n"); 109 return; 110 } 111 } 112 if (acctp == NULL) 113 return; 114 (void)VFS_STATFS(acctp->v_mount, &sb, (struct proc *)0); 115 if (sb.f_bavail <= acctsuspend * sb.f_blocks / 100) { 116 savacctp = acctp; 117 acctp = NULL; 118 log(LOG_NOTICE, "Accounting suspended\n"); 119 } 120 timeout(acctwatch, (caddr_t)resettime, hzto(resettime)); 121 } 122 123 /* 124 * This routine calculates an accounting record for a process and, 125 * if accounting is enabled, writes it to the accounting file. 126 */ 127 acct(p) 128 register struct proc *p; 129 { 130 register struct rusage *ru; 131 struct vnode *vp; 132 struct timeval t, ut, st; 133 int i, s; 134 struct acct acctbuf; 135 register struct acct *ap = &acctbuf; 136 137 if ((vp = acctp) == NULL) 138 return (0); 139 bcopy(p->p_comm, ap->ac_comm, sizeof(ap->ac_comm)); 140 ru = &p->p_stats->p_ru; 141 s = splclock(); 142 ut = p->p_utime; 143 st = p->p_stime; 144 t = time; 145 splx(s); 146 ap->ac_utime = compress(ut.tv_sec, ut.tv_usec); 147 ap->ac_stime = compress(st.tv_sec, st.tv_usec); 148 timevalsub(&t, &p->p_stats->p_start); 149 ap->ac_etime = compress(t.tv_sec, t.tv_usec); 150 ap->ac_btime = p->p_stats->p_start.tv_sec; 151 ap->ac_uid = p->p_cred->p_ruid; 152 ap->ac_gid = p->p_cred->p_rgid; 153 t = st; 154 timevaladd(&t, &ut); 155 if (i = t.tv_sec * hz + t.tv_usec / tick) 156 ap->ac_mem = (ru->ru_ixrss + ru->ru_idrss + ru->ru_isrss) / i; 157 else 158 ap->ac_mem = 0; 159 ap->ac_io = compress(ru->ru_inblock + ru->ru_oublock, (long)0); 160 if (p->p_flag&SCTTY && p->p_session->s_ttyp) 161 ap->ac_tty = p->p_session->s_ttyp->t_dev; 162 else 163 ap->ac_tty = NODEV; 164 ap->ac_flag = p->p_acflag; 165 return (vn_rdwr(UIO_WRITE, vp, (caddr_t)ap, sizeof (acctbuf), (off_t)0, 166 UIO_SYSSPACE, IO_UNIT|IO_APPEND, p->p_ucred, (int *)0, 167 (struct proc *)0)); 168 } 169 170 /* 171 * Produce a pseudo-floating point representation 172 * with 3 bits base-8 exponent, 13 bits fraction. 173 */ 174 compress(t, ut) 175 register long t; 176 long ut; 177 { 178 register exp = 0, round = 0; 179 180 t = t * AHZ; /* compiler will convert only this format to a shift */ 181 if (ut) 182 t += ut / (1000000 / AHZ); 183 while (t >= 8192) { 184 exp++; 185 round = t&04; 186 t >>= 3; 187 } 188 if (round) { 189 t++; 190 if (t >= 8192) { 191 t >>= 3; 192 exp++; 193 } 194 } 195 return ((exp<<13) + t); 196 } 197