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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
/* Copyright (C) 2009-2017 Free Software Foundation, Inc.
Contributed by Richard Henderson <rth@redhat.com>.
This file is part of the GNU Transactional Memory Library (libitm).
Libitm is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
Libitm is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for
more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#include "libitm_i.h"
using namespace GTM;
struct clone_entry
{
void *orig, *clone;
};
struct clone_table
{
clone_entry *table;
size_t size;
clone_table *next;
};
static clone_table *all_tables;
static void *
find_clone (void *ptr)
{
clone_table *table;
for (table = all_tables; table ; table = table->next)
{
clone_entry *t = table->table;
size_t lo = 0, hi = table->size, i;
/* Quick test for whether PTR is present in this table. */
if (ptr < t[0].orig || ptr > t[hi - 1].orig)
continue;
/* Otherwise binary search. */
while (lo < hi)
{
i = (lo + hi) / 2;
if (ptr < t[i].orig)
hi = i;
else if (ptr > t[i].orig)
lo = i + 1;
else
return t[i].clone;
}
/* Given the quick test above, if we don't find the entry in
this table then it doesn't exist. */
break;
}
return NULL;
}
void * ITM_REGPARM
_ITM_getTMCloneOrIrrevocable (void *ptr)
{
void *ret = find_clone (ptr);
if (ret)
return ret;
gtm_thr()->serialirr_mode ();
return ptr;
}
void * ITM_REGPARM
_ITM_getTMCloneSafe (void *ptr)
{
void *ret = find_clone (ptr);
if (ret == NULL)
abort ();
return ret;
}
static int
clone_entry_compare (const void *a, const void *b)
{
const clone_entry *aa = (const clone_entry *)a;
const clone_entry *bb = (const clone_entry *)b;
if (aa->orig < bb->orig)
return -1;
else if (aa->orig > bb->orig)
return 1;
else
return 0;
}
namespace {
// Within find_clone, we know that we are inside a transaction. Because
// of that, we have already synchronized with serial_lock. By taking the
// serial_lock for write, we exclude all transactions while we make this
// change to the clone tables, without having to synchronize on a separate
// lock. Do be careful not to attempt a recursive write lock.
class ExcludeTransaction
{
bool do_lock;
public:
ExcludeTransaction()
{
gtm_thread *tx = gtm_thr();
do_lock = !(tx && (tx->state & gtm_thread::STATE_SERIAL));
if (do_lock)
gtm_thread::serial_lock.write_lock ();
}
~ExcludeTransaction()
{
if (do_lock)
gtm_thread::serial_lock.write_unlock ();
}
};
} // end anon namespace
void
_ITM_registerTMCloneTable (void *xent, size_t size)
{
clone_entry *ent = static_cast<clone_entry *>(xent);
clone_table *table;
table = (clone_table *) xmalloc (sizeof (clone_table));
table->table = ent;
table->size = size;
qsort (ent, size, sizeof (clone_entry), clone_entry_compare);
// Hold the serial_lock while we update the ALL_TABLES datastructure.
{
ExcludeTransaction exclude;
table->next = all_tables;
all_tables = table;
}
}
void
_ITM_deregisterTMCloneTable (void *xent)
{
clone_entry *ent = static_cast<clone_entry *>(xent);
clone_table *tab;
// Hold the serial_lock while we update the ALL_TABLES datastructure.
{
ExcludeTransaction exclude;
clone_table **pprev;
for (pprev = &all_tables;
tab = *pprev, tab->table != ent;
pprev = &tab->next)
continue;
*pprev = tab->next;
}
free (tab);
}
|