cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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atomic.h (1781B)

      1/* SPDX-License-Identifier: GPL-2.0-or-later */
      2/******************************************************************************
      3 *
      4 *   Copyright © International Business Machines  Corp., 2009
      5 *
      6 * DESCRIPTION
      7 *      GCC atomic builtin wrappers
      8 *      http://gcc.gnu.org/onlinedocs/gcc-4.1.0/gcc/Atomic-Builtins.html
      9 *
     10 * AUTHOR
     11 *      Darren Hart <dvhart@linux.intel.com>
     12 *
     13 * HISTORY
     14 *      2009-Nov-17: Initial version by Darren Hart <dvhart@linux.intel.com>
     15 *
     16 *****************************************************************************/
     17
     18#ifndef _ATOMIC_H
     19#define _ATOMIC_H
     20
     21typedef struct {
     22	volatile int val;
     23} atomic_t;
     24
     25#define ATOMIC_INITIALIZER { 0 }
     26
     27/**
     28 * atomic_cmpxchg() - Atomic compare and exchange
     29 * @uaddr:	The address of the futex to be modified
     30 * @oldval:	The expected value of the futex
     31 * @newval:	The new value to try and assign the futex
     32 *
     33 * Return the old value of addr->val.
     34 */
     35static inline int
     36atomic_cmpxchg(atomic_t *addr, int oldval, int newval)
     37{
     38	return __sync_val_compare_and_swap(&addr->val, oldval, newval);
     39}
     40
     41/**
     42 * atomic_inc() - Atomic incrememnt
     43 * @addr:	Address of the variable to increment
     44 *
     45 * Return the new value of addr->val.
     46 */
     47static inline int
     48atomic_inc(atomic_t *addr)
     49{
     50	return __sync_add_and_fetch(&addr->val, 1);
     51}
     52
     53/**
     54 * atomic_dec() - Atomic decrement
     55 * @addr:	Address of the variable to decrement
     56 *
     57 * Return the new value of addr-val.
     58 */
     59static inline int
     60atomic_dec(atomic_t *addr)
     61{
     62	return __sync_sub_and_fetch(&addr->val, 1);
     63}
     64
     65/**
     66 * atomic_set() - Atomic set
     67 * @addr:	Address of the variable to set
     68 * @newval:	New value for the atomic_t
     69 *
     70 * Return the new value of addr->val.
     71 */
     72static inline int
     73atomic_set(atomic_t *addr, int newval)
     74{
     75	addr->val = newval;
     76	return newval;
     77}
     78
     79#endif