Subversion Repositories HelenOS

Rev

Rev 1965 | Only display areas with differences | Ignore whitespace | Details | Blame | Last modification | View Log | RSS feed

Rev 1965 Rev 1968
1
/*
1
/*
2
 * Copyright (C) 2005 Jakub Jermar
2
 * Copyright (C) 2005 Jakub Jermar
3
 * All rights reserved.
3
 * All rights reserved.
4
 *
4
 *
5
 * Redistribution and use in source and binary forms, with or without
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
6
 * modification, are permitted provided that the following conditions
7
 * are met:
7
 * are met:
8
 *
8
 *
9
 * - Redistributions of source code must retain the above copyright
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
15
 *   derived from this software without specific prior written permission.
16
 *
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
27
 */
28
 
28
 
29
#ifndef __ia32_BARRIER_H__
29
#ifndef __ia32_BARRIER_H__
30
#define __ia32_BARRIER_H__
30
#define __ia32_BARRIER_H__
31
 
31
 
32
/*
32
/*
33
 * NOTE:
33
 * NOTE:
34
 * No barriers for critical section (i.e. spinlock) on IA-32 are needed:
34
 * No barriers for critical section (i.e. spinlock) on IA-32 are needed:
35
 * - spinlock_lock() and spinlock_trylock() use serializing XCHG instruction
35
 * - spinlock_lock() and spinlock_trylock() use serializing XCHG instruction
36
 * - writes cannot pass reads on IA-32 => spinlock_unlock() needs no barriers
36
 * - writes cannot pass reads on IA-32 => spinlock_unlock() needs no barriers
37
 */
37
 */
38
 
38
 
39
/*
39
/*
40
 * Provisions are made to prevent compiler from reordering instructions itself.
40
 * Provisions are made to prevent compiler from reordering instructions itself.
41
 */
41
 */
42
 
42
 
43
#define CS_ENTER_BARRIER()  __asm__ volatile ("" ::: "memory")
43
#define CS_ENTER_BARRIER()  __asm__ volatile ("" ::: "memory")
44
#define CS_LEAVE_BARRIER()  __asm__ volatile ("" ::: "memory")
44
#define CS_LEAVE_BARRIER()  __asm__ volatile ("" ::: "memory")
45
 
45
 
46
static inline void cpuid_serialization(void)
46
static inline void cpuid_serialization(void)
47
{
47
{
48
    __asm__ volatile (
48
    __asm__ volatile (
49
        "xorl %%eax, %%eax\n"
49
        "xorl %%eax, %%eax\n"
50
        "cpuid\n"
50
        "cpuid\n"
51
        ::: "eax", "ebx", "ecx", "edx", "memory"
51
        ::: "eax", "ebx", "ecx", "edx", "memory"
52
    );
52
    );
53
}
53
}
54
 
54
 
55
#ifdef CONFIG_FENCES_P4
55
#ifdef CONFIG_FENCES_P4
56
#   define memory_barrier()     __asm__ volatile ("mfence\n" ::: "memory")
56
#   define memory_barrier()     __asm__ volatile ("mfence\n" ::: "memory")
57
#   define read_barrier()       __asm__ volatile ("lfence\n" ::: "memory")
57
#   define read_barrier()       __asm__ volatile ("lfence\n" ::: "memory")
58
#   ifdef CONFIG_WEAK_MEMORY
58
#   ifdef CONFIG_WEAK_MEMORY
59
#       define write_barrier()  __asm__ volatile ("sfence\n" ::: "memory")
59
#       define write_barrier()  __asm__ volatile ("sfence\n" ::: "memory")
60
#   else
60
#   else
61
#       define write_barrier()  __asm__ volatile( "" ::: "memory");
61
#       define write_barrier()  __asm__ volatile( "" ::: "memory");
62
#   endif
62
#   endif
63
#elif CONFIG_FENCES_P3
63
#elif CONFIG_FENCES_P3
64
#   define memory_barrier()     cpuid_serialization()
64
#   define memory_barrier()     cpuid_serialization()
65
#   define read_barrier()       cpuid_serialization()
65
#   define read_barrier()       cpuid_serialization()
66
#   ifdef CONFIG_WEAK_MEMORY
66
#   ifdef CONFIG_WEAK_MEMORY
67
#       define write_barrier()  __asm__ volatile ("sfence\n" ::: "memory")
67
#       define write_barrier()  __asm__ volatile ("sfence\n" ::: "memory")
68
#   else
68
#   else
69
#       define write_barrier()  __asm__ volatile( "" ::: "memory");
69
#       define write_barrier()  __asm__ volatile( "" ::: "memory");
70
#   endif
70
#   endif
71
#else
71
#else
72
#   define memory_barrier()     cpuid_serialization()
72
#   define memory_barrier()     cpuid_serialization()
73
#   define read_barrier()       cpuid_serialization()
73
#   define read_barrier()       cpuid_serialization()
74
#   ifdef CONFIG_WEAK_MEMORY
74
#   ifdef CONFIG_WEAK_MEMORY
75
#       define write_barrier()  cpuid_serialization()
75
#       define write_barrier()  cpuid_serialization()
76
#   else
76
#   else
77
#       define write_barrier()  __asm__ volatile( "" ::: "memory");
77
#       define write_barrier()  __asm__ volatile( "" ::: "memory");
78
#   endif
78
#   endif
79
#endif
79
#endif
80
 
80
 
81
#endif
81
#endif
82
 
82