Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/acct.c |
| 3 | * |
| 4 | * BSD Process Accounting for Linux |
| 5 | * |
| 6 | * Author: Marco van Wieringen <mvw@planets.elm.net> |
| 7 | * |
| 8 | * Some code based on ideas and code from: |
| 9 | * Thomas K. Dyas <tdyas@eden.rutgers.edu> |
| 10 | * |
| 11 | * This file implements BSD-style process accounting. Whenever any |
| 12 | * process exits, an accounting record of type "struct acct" is |
| 13 | * written to the file specified with the acct() system call. It is |
| 14 | * up to user-level programs to do useful things with the accounting |
| 15 | * log. The kernel just provides the raw accounting information. |
| 16 | * |
| 17 | * (C) Copyright 1995 - 1997 Marco van Wieringen - ELM Consultancy B.V. |
| 18 | * |
| 19 | * Plugged two leaks. 1) It didn't return acct_file into the free_filps if |
| 20 | * the file happened to be read-only. 2) If the accounting was suspended |
| 21 | * due to the lack of space it happily allowed to reopen it and completely |
| 22 | * lost the old acct_file. 3/10/98, Al Viro. |
| 23 | * |
| 24 | * Now we silently close acct_file on attempt to reopen. Cleaned sys_acct(). |
| 25 | * XTerms and EMACS are manifestations of pure evil. 21/10/98, AV. |
| 26 | * |
| 27 | * Fixed a nasty interaction with with sys_umount(). If the accointing |
| 28 | * was suspeneded we failed to stop it on umount(). Messy. |
| 29 | * Another one: remount to readonly didn't stop accounting. |
| 30 | * Question: what should we do if we have CAP_SYS_ADMIN but not |
| 31 | * CAP_SYS_PACCT? Current code does the following: umount returns -EBUSY |
| 32 | * unless we are messing with the root. In that case we are getting a |
| 33 | * real mess with do_remount_sb(). 9/11/98, AV. |
| 34 | * |
| 35 | * Fixed a bunch of races (and pair of leaks). Probably not the best way, |
| 36 | * but this one obviously doesn't introduce deadlocks. Later. BTW, found |
| 37 | * one race (and leak) in BSD implementation. |
| 38 | * OK, that's better. ANOTHER race and leak in BSD variant. There always |
| 39 | * is one more bug... 10/11/98, AV. |
| 40 | * |
| 41 | * Oh, fsck... Oopsable SMP race in do_process_acct() - we must hold |
| 42 | * ->mmap_sem to walk the vma list of current->mm. Nasty, since it leaks |
| 43 | * a struct file opened for write. Fixed. 2/6/2000, AV. |
| 44 | */ |
| 45 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | #include <linux/mm.h> |
| 47 | #include <linux/slab.h> |
| 48 | #include <linux/acct.h> |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 49 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | #include <linux/file.h> |
| 51 | #include <linux/tty.h> |
| 52 | #include <linux/security.h> |
| 53 | #include <linux/vfs.h> |
| 54 | #include <linux/jiffies.h> |
| 55 | #include <linux/times.h> |
| 56 | #include <linux/syscalls.h> |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 57 | #include <linux/mount.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | #include <asm/uaccess.h> |
| 59 | #include <asm/div64.h> |
| 60 | #include <linux/blkdev.h> /* sector_div */ |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 61 | #include <linux/pid_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | |
| 63 | /* |
| 64 | * These constants control the amount of freespace that suspend and |
| 65 | * resume the process accounting system, and the time delay between |
| 66 | * each check. |
| 67 | * Turned into sysctl-controllable parameters. AV, 12/11/98 |
| 68 | */ |
| 69 | |
| 70 | int acct_parm[3] = {4, 2, 30}; |
| 71 | #define RESUME (acct_parm[0]) /* >foo% free space - resume */ |
| 72 | #define SUSPEND (acct_parm[1]) /* <foo% free space - suspend */ |
| 73 | #define ACCT_TIMEOUT (acct_parm[2]) /* foo second timeout between checks */ |
| 74 | |
| 75 | /* |
| 76 | * External references and all of the globals. |
| 77 | */ |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 78 | static void do_acct_process(struct pid_namespace *ns, struct file *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | |
| 80 | /* |
| 81 | * This structure is used so that all the data protected by lock |
| 82 | * can be placed in the same cache line as the lock. This primes |
| 83 | * the cache line to have the data after getting the lock. |
| 84 | */ |
| 85 | struct acct_glbs { |
| 86 | spinlock_t lock; |
| 87 | volatile int active; |
| 88 | volatile int needcheck; |
| 89 | struct file *file; |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 90 | struct pid_namespace *ns; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | struct timer_list timer; |
| 92 | }; |
| 93 | |
Peter Zijlstra | 6cfd76a | 2006-12-06 20:37:22 -0800 | [diff] [blame] | 94 | static struct acct_glbs acct_globals __cacheline_aligned = |
| 95 | {__SPIN_LOCK_UNLOCKED(acct_globals.lock)}; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | |
| 97 | /* |
| 98 | * Called whenever the timer says to check the free space. |
| 99 | */ |
| 100 | static void acct_timeout(unsigned long unused) |
| 101 | { |
| 102 | acct_globals.needcheck = 1; |
| 103 | } |
| 104 | |
| 105 | /* |
| 106 | * Check the amount of free space and suspend/resume accordingly. |
| 107 | */ |
| 108 | static int check_free_space(struct file *file) |
| 109 | { |
| 110 | struct kstatfs sbuf; |
| 111 | int res; |
| 112 | int act; |
| 113 | sector_t resume; |
| 114 | sector_t suspend; |
| 115 | |
| 116 | spin_lock(&acct_globals.lock); |
| 117 | res = acct_globals.active; |
| 118 | if (!file || !acct_globals.needcheck) |
| 119 | goto out; |
| 120 | spin_unlock(&acct_globals.lock); |
| 121 | |
| 122 | /* May block */ |
Josef "Jeff" Sipek | f3a43f3 | 2006-12-08 02:36:43 -0800 | [diff] [blame] | 123 | if (vfs_statfs(file->f_path.dentry, &sbuf)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | return res; |
| 125 | suspend = sbuf.f_blocks * SUSPEND; |
| 126 | resume = sbuf.f_blocks * RESUME; |
| 127 | |
| 128 | sector_div(suspend, 100); |
| 129 | sector_div(resume, 100); |
| 130 | |
| 131 | if (sbuf.f_bavail <= suspend) |
| 132 | act = -1; |
| 133 | else if (sbuf.f_bavail >= resume) |
| 134 | act = 1; |
| 135 | else |
| 136 | act = 0; |
| 137 | |
| 138 | /* |
| 139 | * If some joker switched acct_globals.file under us we'ld better be |
| 140 | * silent and _not_ touch anything. |
| 141 | */ |
| 142 | spin_lock(&acct_globals.lock); |
| 143 | if (file != acct_globals.file) { |
| 144 | if (act) |
| 145 | res = act>0; |
| 146 | goto out; |
| 147 | } |
| 148 | |
| 149 | if (acct_globals.active) { |
| 150 | if (act < 0) { |
| 151 | acct_globals.active = 0; |
| 152 | printk(KERN_INFO "Process accounting paused\n"); |
| 153 | } |
| 154 | } else { |
| 155 | if (act > 0) { |
| 156 | acct_globals.active = 1; |
| 157 | printk(KERN_INFO "Process accounting resumed\n"); |
| 158 | } |
| 159 | } |
| 160 | |
| 161 | del_timer(&acct_globals.timer); |
| 162 | acct_globals.needcheck = 0; |
| 163 | acct_globals.timer.expires = jiffies + ACCT_TIMEOUT*HZ; |
| 164 | add_timer(&acct_globals.timer); |
| 165 | res = acct_globals.active; |
| 166 | out: |
| 167 | spin_unlock(&acct_globals.lock); |
| 168 | return res; |
| 169 | } |
| 170 | |
| 171 | /* |
Randy Dunlap | 417ef53 | 2005-09-10 00:26:39 -0700 | [diff] [blame] | 172 | * Close the old accounting file (if currently open) and then replace |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | * it with file (if non-NULL). |
| 174 | * |
| 175 | * NOTE: acct_globals.lock MUST be held on entry and exit. |
| 176 | */ |
| 177 | static void acct_file_reopen(struct file *file) |
| 178 | { |
| 179 | struct file *old_acct = NULL; |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 180 | struct pid_namespace *old_ns = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | |
| 182 | if (acct_globals.file) { |
| 183 | old_acct = acct_globals.file; |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 184 | old_ns = acct_globals.ns; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | del_timer(&acct_globals.timer); |
| 186 | acct_globals.active = 0; |
| 187 | acct_globals.needcheck = 0; |
| 188 | acct_globals.file = NULL; |
| 189 | } |
| 190 | if (file) { |
| 191 | acct_globals.file = file; |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 192 | acct_globals.ns = get_pid_ns(task_active_pid_ns(current)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | acct_globals.needcheck = 0; |
| 194 | acct_globals.active = 1; |
| 195 | /* It's been deleted if it was used before so this is safe */ |
| 196 | init_timer(&acct_globals.timer); |
| 197 | acct_globals.timer.function = acct_timeout; |
| 198 | acct_globals.timer.expires = jiffies + ACCT_TIMEOUT*HZ; |
| 199 | add_timer(&acct_globals.timer); |
| 200 | } |
| 201 | if (old_acct) { |
Josef "Jeff" Sipek | f3a43f3 | 2006-12-08 02:36:43 -0800 | [diff] [blame] | 202 | mnt_unpin(old_acct->f_path.mnt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | spin_unlock(&acct_globals.lock); |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 204 | do_acct_process(old_ns, old_acct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | filp_close(old_acct, NULL); |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 206 | put_pid_ns(old_ns); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | spin_lock(&acct_globals.lock); |
| 208 | } |
| 209 | } |
| 210 | |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 211 | static int acct_on(char *name) |
| 212 | { |
| 213 | struct file *file; |
| 214 | int error; |
| 215 | |
| 216 | /* Difference from BSD - they don't do O_APPEND */ |
| 217 | file = filp_open(name, O_WRONLY|O_APPEND|O_LARGEFILE, 0); |
| 218 | if (IS_ERR(file)) |
| 219 | return PTR_ERR(file); |
| 220 | |
Josef "Jeff" Sipek | f3a43f3 | 2006-12-08 02:36:43 -0800 | [diff] [blame] | 221 | if (!S_ISREG(file->f_path.dentry->d_inode->i_mode)) { |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 222 | filp_close(file, NULL); |
| 223 | return -EACCES; |
| 224 | } |
| 225 | |
| 226 | if (!file->f_op->write) { |
| 227 | filp_close(file, NULL); |
| 228 | return -EIO; |
| 229 | } |
| 230 | |
| 231 | error = security_acct(file); |
| 232 | if (error) { |
| 233 | filp_close(file, NULL); |
| 234 | return error; |
| 235 | } |
| 236 | |
| 237 | spin_lock(&acct_globals.lock); |
Josef "Jeff" Sipek | f3a43f3 | 2006-12-08 02:36:43 -0800 | [diff] [blame] | 238 | mnt_pin(file->f_path.mnt); |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 239 | acct_file_reopen(file); |
| 240 | spin_unlock(&acct_globals.lock); |
| 241 | |
Josef "Jeff" Sipek | f3a43f3 | 2006-12-08 02:36:43 -0800 | [diff] [blame] | 242 | mntput(file->f_path.mnt); /* it's pinned, now give up active reference */ |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 243 | |
| 244 | return 0; |
| 245 | } |
| 246 | |
Randy Dunlap | 417ef53 | 2005-09-10 00:26:39 -0700 | [diff] [blame] | 247 | /** |
| 248 | * sys_acct - enable/disable process accounting |
| 249 | * @name: file name for accounting records or NULL to shutdown accounting |
| 250 | * |
| 251 | * Returns 0 for success or negative errno values for failure. |
| 252 | * |
| 253 | * sys_acct() is the only system call needed to implement process |
| 254 | * accounting. It takes the name of the file where accounting records |
| 255 | * should be written. If the filename is NULL, accounting will be |
| 256 | * shutdown. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | */ |
| 258 | asmlinkage long sys_acct(const char __user *name) |
| 259 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | int error; |
| 261 | |
| 262 | if (!capable(CAP_SYS_PACCT)) |
| 263 | return -EPERM; |
| 264 | |
| 265 | if (name) { |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 266 | char *tmp = getname(name); |
| 267 | if (IS_ERR(tmp)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | return (PTR_ERR(tmp)); |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 269 | error = acct_on(tmp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | putname(tmp); |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 271 | } else { |
| 272 | error = security_acct(NULL); |
| 273 | if (!error) { |
| 274 | spin_lock(&acct_globals.lock); |
| 275 | acct_file_reopen(NULL); |
| 276 | spin_unlock(&acct_globals.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | } |
| 278 | } |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 279 | return error; |
| 280 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 282 | /** |
| 283 | * acct_auto_close - turn off a filesystem's accounting if it is on |
| 284 | * @m: vfsmount being shut down |
| 285 | * |
| 286 | * If the accounting is turned on for a file in the subtree pointed to |
| 287 | * to by m, turn accounting off. Done when m is about to die. |
| 288 | */ |
| 289 | void acct_auto_close_mnt(struct vfsmount *m) |
| 290 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | spin_lock(&acct_globals.lock); |
Josef "Jeff" Sipek | f3a43f3 | 2006-12-08 02:36:43 -0800 | [diff] [blame] | 292 | if (acct_globals.file && acct_globals.file->f_path.mnt == m) |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 293 | acct_file_reopen(NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | spin_unlock(&acct_globals.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | } |
| 296 | |
Randy Dunlap | 417ef53 | 2005-09-10 00:26:39 -0700 | [diff] [blame] | 297 | /** |
| 298 | * acct_auto_close - turn off a filesystem's accounting if it is on |
| 299 | * @sb: super block for the filesystem |
| 300 | * |
| 301 | * If the accounting is turned on for a file in the filesystem pointed |
| 302 | * to by sb, turn accounting off. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | */ |
| 304 | void acct_auto_close(struct super_block *sb) |
| 305 | { |
| 306 | spin_lock(&acct_globals.lock); |
| 307 | if (acct_globals.file && |
Josef "Jeff" Sipek | f3a43f3 | 2006-12-08 02:36:43 -0800 | [diff] [blame] | 308 | acct_globals.file->f_path.mnt->mnt_sb == sb) { |
Al Viro | 7b7b1ac | 2005-11-07 17:13:39 -0500 | [diff] [blame] | 309 | acct_file_reopen(NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | } |
| 311 | spin_unlock(&acct_globals.lock); |
| 312 | } |
| 313 | |
| 314 | /* |
| 315 | * encode an unsigned long into a comp_t |
| 316 | * |
| 317 | * This routine has been adopted from the encode_comp_t() function in |
| 318 | * the kern_acct.c file of the FreeBSD operating system. The encoding |
| 319 | * is a 13-bit fraction with a 3-bit (base 8) exponent. |
| 320 | */ |
| 321 | |
| 322 | #define MANTSIZE 13 /* 13 bit mantissa. */ |
| 323 | #define EXPSIZE 3 /* Base 8 (3 bit) exponent. */ |
| 324 | #define MAXFRACT ((1 << MANTSIZE) - 1) /* Maximum fractional value. */ |
| 325 | |
| 326 | static comp_t encode_comp_t(unsigned long value) |
| 327 | { |
| 328 | int exp, rnd; |
| 329 | |
| 330 | exp = rnd = 0; |
| 331 | while (value > MAXFRACT) { |
| 332 | rnd = value & (1 << (EXPSIZE - 1)); /* Round up? */ |
| 333 | value >>= EXPSIZE; /* Base 8 exponent == 3 bit shift. */ |
| 334 | exp++; |
| 335 | } |
| 336 | |
| 337 | /* |
Daniel Walker | 6ae965c | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 338 | * If we need to round up, do it (and handle overflow correctly). |
| 339 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | if (rnd && (++value > MAXFRACT)) { |
| 341 | value >>= EXPSIZE; |
| 342 | exp++; |
| 343 | } |
| 344 | |
| 345 | /* |
Daniel Walker | 6ae965c | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 346 | * Clean it up and polish it off. |
| 347 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | exp <<= MANTSIZE; /* Shift the exponent into place */ |
| 349 | exp += value; /* and add on the mantissa. */ |
| 350 | return exp; |
| 351 | } |
| 352 | |
| 353 | #if ACCT_VERSION==1 || ACCT_VERSION==2 |
| 354 | /* |
| 355 | * encode an u64 into a comp2_t (24 bits) |
| 356 | * |
| 357 | * Format: 5 bit base 2 exponent, 20 bits mantissa. |
| 358 | * The leading bit of the mantissa is not stored, but implied for |
| 359 | * non-zero exponents. |
| 360 | * Largest encodable value is 50 bits. |
| 361 | */ |
| 362 | |
| 363 | #define MANTSIZE2 20 /* 20 bit mantissa. */ |
| 364 | #define EXPSIZE2 5 /* 5 bit base 2 exponent. */ |
| 365 | #define MAXFRACT2 ((1ul << MANTSIZE2) - 1) /* Maximum fractional value. */ |
| 366 | #define MAXEXP2 ((1 <<EXPSIZE2) - 1) /* Maximum exponent. */ |
| 367 | |
| 368 | static comp2_t encode_comp2_t(u64 value) |
| 369 | { |
Daniel Walker | 6ae965c | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 370 | int exp, rnd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 371 | |
Daniel Walker | 6ae965c | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 372 | exp = (value > (MAXFRACT2>>1)); |
| 373 | rnd = 0; |
| 374 | while (value > MAXFRACT2) { |
| 375 | rnd = value & 1; |
| 376 | value >>= 1; |
| 377 | exp++; |
| 378 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | |
Daniel Walker | 6ae965c | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 380 | /* |
| 381 | * If we need to round up, do it (and handle overflow correctly). |
| 382 | */ |
| 383 | if (rnd && (++value > MAXFRACT2)) { |
| 384 | value >>= 1; |
| 385 | exp++; |
| 386 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | |
Daniel Walker | 6ae965c | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 388 | if (exp > MAXEXP2) { |
| 389 | /* Overflow. Return largest representable number instead. */ |
| 390 | return (1ul << (MANTSIZE2+EXPSIZE2-1)) - 1; |
| 391 | } else { |
| 392 | return (value & (MAXFRACT2>>1)) | (exp << (MANTSIZE2-1)); |
| 393 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | } |
| 395 | #endif |
| 396 | |
| 397 | #if ACCT_VERSION==3 |
| 398 | /* |
| 399 | * encode an u64 into a 32 bit IEEE float |
| 400 | */ |
| 401 | static u32 encode_float(u64 value) |
| 402 | { |
| 403 | unsigned exp = 190; |
| 404 | unsigned u; |
| 405 | |
| 406 | if (value==0) return 0; |
| 407 | while ((s64)value > 0){ |
| 408 | value <<= 1; |
| 409 | exp--; |
| 410 | } |
| 411 | u = (u32)(value >> 40) & 0x7fffffu; |
| 412 | return u | (exp << 23); |
| 413 | } |
| 414 | #endif |
| 415 | |
| 416 | /* |
| 417 | * Write an accounting entry for an exiting process |
| 418 | * |
| 419 | * The acct_process() call is the workhorse of the process |
| 420 | * accounting system. The struct acct is built here and then written |
| 421 | * into the accounting file. This function should only be called from |
Ingo Molnar | bcbe4a0 | 2007-11-26 21:21:49 +0100 | [diff] [blame] | 422 | * do_exit() or when switching to a different output file. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | */ |
| 424 | |
| 425 | /* |
| 426 | * do_acct_process does all actual work. Caller holds the reference to file. |
| 427 | */ |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 428 | static void do_acct_process(struct pid_namespace *ns, struct file *file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | { |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 430 | struct pacct_struct *pacct = ¤t->signal->pacct; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | acct_t ac; |
| 432 | mm_segment_t fs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | unsigned long flim; |
| 434 | u64 elapsed; |
| 435 | u64 run_time; |
| 436 | struct timespec uptime; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 437 | struct tty_struct *tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | |
| 439 | /* |
| 440 | * First check to see if there is enough free_space to continue |
| 441 | * the process accounting system. |
| 442 | */ |
| 443 | if (!check_free_space(file)) |
| 444 | return; |
| 445 | |
| 446 | /* |
| 447 | * Fill the accounting struct with the needed info as recorded |
| 448 | * by the different kernel functions. |
| 449 | */ |
| 450 | memset((caddr_t)&ac, 0, sizeof(acct_t)); |
| 451 | |
| 452 | ac.ac_version = ACCT_VERSION | ACCT_BYTEORDER; |
| 453 | strlcpy(ac.ac_comm, current->comm, sizeof(ac.ac_comm)); |
| 454 | |
| 455 | /* calculate run_time in nsec*/ |
| 456 | do_posix_clock_monotonic_gettime(&uptime); |
| 457 | run_time = (u64)uptime.tv_sec*NSEC_PER_SEC + uptime.tv_nsec; |
KaiGai Kohei | bb231fe | 2006-03-31 02:30:45 -0800 | [diff] [blame] | 458 | run_time -= (u64)current->group_leader->start_time.tv_sec * NSEC_PER_SEC |
| 459 | + current->group_leader->start_time.tv_nsec; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 460 | /* convert nsec -> AHZ */ |
| 461 | elapsed = nsec_to_AHZ(run_time); |
| 462 | #if ACCT_VERSION==3 |
| 463 | ac.ac_etime = encode_float(elapsed); |
| 464 | #else |
| 465 | ac.ac_etime = encode_comp_t(elapsed < (unsigned long) -1l ? |
| 466 | (unsigned long) elapsed : (unsigned long) -1l); |
| 467 | #endif |
| 468 | #if ACCT_VERSION==1 || ACCT_VERSION==2 |
| 469 | { |
| 470 | /* new enlarged etime field */ |
| 471 | comp2_t etime = encode_comp2_t(elapsed); |
| 472 | ac.ac_etime_hi = etime >> 16; |
| 473 | ac.ac_etime_lo = (u16) etime; |
| 474 | } |
| 475 | #endif |
| 476 | do_div(elapsed, AHZ); |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 477 | ac.ac_btime = get_seconds() - elapsed; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | /* we really need to bite the bullet and change layout */ |
| 479 | ac.ac_uid = current->uid; |
| 480 | ac.ac_gid = current->gid; |
| 481 | #if ACCT_VERSION==2 |
| 482 | ac.ac_ahz = AHZ; |
| 483 | #endif |
| 484 | #if ACCT_VERSION==1 || ACCT_VERSION==2 |
| 485 | /* backward-compatible 16 bit fields */ |
| 486 | ac.ac_uid16 = current->uid; |
| 487 | ac.ac_gid16 = current->gid; |
| 488 | #endif |
| 489 | #if ACCT_VERSION==3 |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 490 | ac.ac_pid = task_tgid_nr_ns(current, ns); |
Pavel Emelyanov | a846a19 | 2008-03-24 12:29:52 -0700 | [diff] [blame] | 491 | rcu_read_lock(); |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 492 | ac.ac_ppid = task_tgid_nr_ns(rcu_dereference(current->real_parent), ns); |
Pavel Emelyanov | a846a19 | 2008-03-24 12:29:52 -0700 | [diff] [blame] | 493 | rcu_read_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 494 | #endif |
| 495 | |
OGAWA Hirofumi | a4afee0 | 2006-07-14 00:24:18 -0700 | [diff] [blame] | 496 | spin_lock_irq(¤t->sighand->siglock); |
Oleg Nesterov | 7bcfa95 | 2006-12-08 02:36:07 -0800 | [diff] [blame] | 497 | tty = current->signal->tty; |
| 498 | ac.ac_tty = tty ? old_encode_dev(tty_devnum(tty)) : 0; |
KaiGai Kohei | 77787bf | 2006-06-25 05:49:26 -0700 | [diff] [blame] | 499 | ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime))); |
| 500 | ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime))); |
KaiGai Kohei | f6ec29a | 2006-06-25 05:49:25 -0700 | [diff] [blame] | 501 | ac.ac_flag = pacct->ac_flag; |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 502 | ac.ac_mem = encode_comp_t(pacct->ac_mem); |
KaiGai Kohei | 77787bf | 2006-06-25 05:49:26 -0700 | [diff] [blame] | 503 | ac.ac_minflt = encode_comp_t(pacct->ac_minflt); |
| 504 | ac.ac_majflt = encode_comp_t(pacct->ac_majflt); |
KaiGai Kohei | f6ec29a | 2006-06-25 05:49:25 -0700 | [diff] [blame] | 505 | ac.ac_exitcode = pacct->ac_exitcode; |
OGAWA Hirofumi | a4afee0 | 2006-07-14 00:24:18 -0700 | [diff] [blame] | 506 | spin_unlock_irq(¤t->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 507 | ac.ac_io = encode_comp_t(0 /* current->io_usage */); /* %% */ |
| 508 | ac.ac_rw = encode_comp_t(ac.ac_io / 1024); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | ac.ac_swaps = encode_comp_t(0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | |
| 511 | /* |
Daniel Walker | 6ae965c | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 512 | * Kernel segment override to datasegment and write it |
| 513 | * to the accounting file. |
| 514 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | fs = get_fs(); |
| 516 | set_fs(KERNEL_DS); |
| 517 | /* |
Daniel Walker | 6ae965c | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 518 | * Accounting records are not subject to resource limits. |
| 519 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 520 | flim = current->signal->rlim[RLIMIT_FSIZE].rlim_cur; |
| 521 | current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY; |
| 522 | file->f_op->write(file, (char *)&ac, |
| 523 | sizeof(acct_t), &file->f_pos); |
| 524 | current->signal->rlim[RLIMIT_FSIZE].rlim_cur = flim; |
| 525 | set_fs(fs); |
| 526 | } |
| 527 | |
Randy Dunlap | 417ef53 | 2005-09-10 00:26:39 -0700 | [diff] [blame] | 528 | /** |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 529 | * acct_init_pacct - initialize a new pacct_struct |
Randy Dunlap | 1dbe83c | 2006-06-27 02:54:01 -0700 | [diff] [blame] | 530 | * @pacct: per-process accounting info struct to initialize |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 531 | */ |
| 532 | void acct_init_pacct(struct pacct_struct *pacct) |
| 533 | { |
| 534 | memset(pacct, 0, sizeof(struct pacct_struct)); |
KaiGai Kohei | 77787bf | 2006-06-25 05:49:26 -0700 | [diff] [blame] | 535 | pacct->ac_utime = pacct->ac_stime = cputime_zero; |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 536 | } |
| 537 | |
| 538 | /** |
| 539 | * acct_collect - collect accounting information into pacct_struct |
KaiGai Kohei | f6ec29a | 2006-06-25 05:49:25 -0700 | [diff] [blame] | 540 | * @exitcode: task exit code |
| 541 | * @group_dead: not 0, if this thread is the last one in the process. |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 542 | */ |
KaiGai Kohei | f6ec29a | 2006-06-25 05:49:25 -0700 | [diff] [blame] | 543 | void acct_collect(long exitcode, int group_dead) |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 544 | { |
| 545 | struct pacct_struct *pacct = ¤t->signal->pacct; |
| 546 | unsigned long vsize = 0; |
| 547 | |
KaiGai Kohei | f6ec29a | 2006-06-25 05:49:25 -0700 | [diff] [blame] | 548 | if (group_dead && current->mm) { |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 549 | struct vm_area_struct *vma; |
| 550 | down_read(¤t->mm->mmap_sem); |
| 551 | vma = current->mm->mmap; |
| 552 | while (vma) { |
| 553 | vsize += vma->vm_end - vma->vm_start; |
| 554 | vma = vma->vm_next; |
| 555 | } |
| 556 | up_read(¤t->mm->mmap_sem); |
| 557 | } |
| 558 | |
KaiGai Kohei | 77787bf | 2006-06-25 05:49:26 -0700 | [diff] [blame] | 559 | spin_lock_irq(¤t->sighand->siglock); |
KaiGai Kohei | f6ec29a | 2006-06-25 05:49:25 -0700 | [diff] [blame] | 560 | if (group_dead) |
| 561 | pacct->ac_mem = vsize / 1024; |
| 562 | if (thread_group_leader(current)) { |
| 563 | pacct->ac_exitcode = exitcode; |
| 564 | if (current->flags & PF_FORKNOEXEC) |
| 565 | pacct->ac_flag |= AFORK; |
| 566 | } |
| 567 | if (current->flags & PF_SUPERPRIV) |
| 568 | pacct->ac_flag |= ASU; |
| 569 | if (current->flags & PF_DUMPCORE) |
| 570 | pacct->ac_flag |= ACORE; |
| 571 | if (current->flags & PF_SIGNALED) |
| 572 | pacct->ac_flag |= AXSIG; |
KaiGai Kohei | 77787bf | 2006-06-25 05:49:26 -0700 | [diff] [blame] | 573 | pacct->ac_utime = cputime_add(pacct->ac_utime, current->utime); |
| 574 | pacct->ac_stime = cputime_add(pacct->ac_stime, current->stime); |
| 575 | pacct->ac_minflt += current->min_flt; |
| 576 | pacct->ac_majflt += current->maj_flt; |
| 577 | spin_unlock_irq(¤t->sighand->siglock); |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 578 | } |
| 579 | |
| 580 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 581 | * acct_process - now just a wrapper around do_acct_process |
Randy Dunlap | 417ef53 | 2005-09-10 00:26:39 -0700 | [diff] [blame] | 582 | * @exitcode: task exit code |
| 583 | * |
| 584 | * handles process accounting for an exiting task |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 585 | */ |
Randy Dunlap | 7f32a25 | 2006-06-27 02:53:25 -0700 | [diff] [blame] | 586 | void acct_process(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | { |
| 588 | struct file *file = NULL; |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 589 | struct pid_namespace *ns; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 590 | |
| 591 | /* |
| 592 | * accelerate the common fastpath: |
| 593 | */ |
| 594 | if (!acct_globals.file) |
| 595 | return; |
| 596 | |
| 597 | spin_lock(&acct_globals.lock); |
| 598 | file = acct_globals.file; |
| 599 | if (unlikely(!file)) { |
| 600 | spin_unlock(&acct_globals.lock); |
| 601 | return; |
| 602 | } |
| 603 | get_file(file); |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 604 | ns = get_pid_ns(acct_globals.ns); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | spin_unlock(&acct_globals.lock); |
| 606 | |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 607 | do_acct_process(ns, file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 608 | fput(file); |
Pavel Emelyanov | 5f7b703 | 2008-03-24 12:29:53 -0700 | [diff] [blame] | 609 | put_pid_ns(ns); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | } |