1/*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
6 * Copyright (c) 2015 François Tigeot
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice unmodified, this list of conditions, and the following
14 *    disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30#ifndef	_LINUXKPI_LINUX_COMPILER_H_
31#define	_LINUXKPI_LINUX_COMPILER_H_
32
33#define	____cacheline_aligned_in_smp	__aligned(CACHE_LINE_SIZE)
34#define	fallthrough			/* FALLTHROUGH */ do { } while(0)
35
36#define	likely(x)			__builtin_expect(!!(x), 1)
37#define	unlikely(x)			__builtin_expect(!!(x), 0)
38#define	barrier()			__asm__ __volatile__("": : :"memory")
39#define	ACCESS_ONCE(x)			(*(volatile __typeof(x) *)&(x))
40#define	WRITE_ONCE(x,v) do {		\
41	barrier();			\
42	ACCESS_ONCE(x) = (v);		\
43	barrier();			\
44} while (0)
45
46#define	READ_ONCE(x) ({			\
47	__typeof(x) __var = ({		\
48		barrier();		\
49		ACCESS_ONCE(x);		\
50	});				\
51	barrier();			\
52	__var;				\
53})
54
55#define	sizeof_field(_s, _m)	sizeof(((_s *)0)->_m)
56
57#endif	/* _LINUXKPI_LINUX_COMPILER_H_ */
58