-/* Compute a serial number for the audit record. Audit records are
- * written to user-space as soon as they are generated, so a complete
- * audit record may be written in several pieces. The timestamp of the
- * record and this serial number are used by the user-space daemon to
- * determine which pieces belong to the same audit record. The
- * (timestamp,serial) tuple is unique for each syscall and is live from
- * syscall entry to syscall exit.
- *
- * Atomic values are only guaranteed to be 24-bit, so we count down.
- *
- * NOTE: Another possibility is to store the formatted records off the
- * audit context (for those records that have a context), and emit them
- * all at syscall exit. However, this could delay the reporting of
- * significant errors until syscall exit (or never, if the system
- * halts). */
-static inline unsigned int audit_serial(void)
-{
- static atomic_t serial = ATOMIC_INIT(0xffffff);
- unsigned int a, b;
-
- do {
- a = atomic_read(&serial);
- if (atomic_dec_and_test(&serial))
- atomic_set(&serial, 0xffffff);
- b = atomic_read(&serial);
- } while (b != a - 1);
-
- return 0xffffff - b;
-}
-