1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
|
/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @ingroup RTEMSScoreSMPBarrier
*
* @brief This source file contains the implementation of
* _SMP_barrier_Wait().
*/
/*
* Copyright (C) 2013, 2014 embedded brains GmbH & Co. KG
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/score/smpbarrier.h>
bool _SMP_barrier_Wait(
SMP_barrier_Control *control,
SMP_barrier_State *state,
unsigned int count
)
{
unsigned int sense = ~state->sense;
unsigned int previous_value;
bool performed_release;
state->sense = sense;
previous_value = _Atomic_Fetch_add_uint(
&control->value,
1U,
ATOMIC_ORDER_RELAXED
);
if ( previous_value + 1U == count ) {
_Atomic_Store_uint( &control->value, 0U, ATOMIC_ORDER_RELAXED );
_Atomic_Store_uint( &control->sense, sense, ATOMIC_ORDER_RELEASE );
performed_release = true;
} else {
while (
_Atomic_Load_uint( &control->sense, ATOMIC_ORDER_ACQUIRE ) != sense
) {
/* Wait */
}
performed_release = false;
}
return performed_release;
}
|
