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
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/* -------------------------------------------------------------- */
/* (C)Copyright 2001,2007, */
/* International Business Machines Corporation, */
/* Sony Computer Entertainment, Incorporated, */
/* Toshiba Corporation, */
/* */
/* All Rights Reserved. */
/* */
/* Redistribution and use in source and binary forms, with or */
/* without modification, are permitted provided that the */
/* following conditions are met: */
/* */
/* - Redistributions of source code must retain the above copyright*/
/* notice, this list of conditions and the following disclaimer. */
/* */
/* - 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. */
/* */
/* - Neither the name of IBM Corporation nor the names of its */
/* contributors may be used to endorse or promote products */
/* derived from this software without specific prior written */
/* permission. */
/* */
/* 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. */
/* -------------------------------------------------------------- */
/* PROLOG END TAG zYx */
#ifndef _SPU_COND_INIT_H_
#define _SPU_COND_INIT_H_
#include "sync_utils.h"
#include "cond.h"
#include <spu_mfcio.h>
/**
* cond_init - initialize condition variable.
* @cond: handle to effective address of condition variable.
*
*
* Conditional Variable - is a synchronization device that allows
* SPE and PPE threads to suspend execution and relinquish the
* processors until some predicate on shared data is satisfied.
* The basic operations on conditions are: signal the condition
* (when the predicate becomes true), and wait for the condition,
* suspending the thread execution until anoter thread signals the
* condition
*
* A condition variable must always be associated with a mutex, to
* avoid the race condition where a thread prepares to wait on a
* condition variable and another thread signals the condition just
* before the first thread actually waits on it.
*
* cond_init initializes the condition variable cond.
*
* cond_signal restarts one of the threads that are waiting on the
* condition variable cond. If no threads are waiting on cond, nothing
* happens. If several threads are waiting on cond, exactly one
* is restarted, but it is not specified which
*
* cond_broadcast restarts all the threads that are waiting on the
* condition variable cond. Nothing happens if no threads are waiting
* on cond
*
* cond_wait atomically unlocks the mutex and waits for the condition
* variable cond to be signaled. The mutex must be lock locked by
* the calling thread on the entrance to cond_wait. Before returning
* to the calling thread, cond_wait re-acquires mutex.
*
* Only one thread initializes a condition variable. Usually, the
* PPE thread initializes a condidtion variable, however, a cond_init
* function is provided here for completeness
*
* Description: Initialize a cond variable to false.
*/
static __inline void _cond_init(cond_ea_t cond )
{
char _tmp[256];
char *tmp = (char *) ALIGN(_tmp, 128);
volatile unsigned short *buf = (volatile unsigned short *) &tmp[0];
unsigned int size = 128, tagid;
unsigned int offset;
addr64 ea64;
unsigned int oldtmask;
unsigned int tagmask;
tagid = mfc_tag_reserve();
tagmask = 1 << (tagid & 31);
ea64.ull = ALIGN128_EA(cond);
offset = OFFSET128_EA_U16(cond);
MFC_DMA(buf, ea64, size, tagid & 31, MFC_GET_CMD);
oldtmask = spu_readch(MFC_RdTagMask);
spu_writech(MFC_WrTagMask, tagmask);
spu_writech(MFC_WrTagUpdate, MFC_TAG_UPDATE_ANY);
spu_readch(MFC_RdTagStat);
/* this is still just one word. since buf is of type
* short, we fit both counts into one word. */
buf[offset] = 0;
buf[offset+1] = 0;
MFC_DMA(buf, ea64, size, (tagid & 31), MFC_PUT_CMD);
spu_writech(MFC_WrTagMask, tagmask);
spu_writech(MFC_WrTagUpdate, MFC_TAG_UPDATE_ANY);
spu_readch(MFC_RdTagStat);
spu_writech(MFC_WrTagMask, oldtmask);
mfc_tag_release (tagid);
}
#endif /* _SPU_COND_INIT_H_ */
|
