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
|
/* Copyright (C) 2009-2019 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"
namespace GTM HIDDEN {
void
gtm_thread::record_allocation (void *ptr, void (*free_fn)(void *))
{
// We do not deallocate before outermost commit, so we should never have
// an existing log entry for a new allocation.
gtm_alloc_action *a = this->alloc_actions.insert((uintptr_t) ptr);
a->free_fn = free_fn;
a->free_fn_sz = 0;
a->allocated = true;
}
void
gtm_thread::forget_allocation (void *ptr, void (*free_fn)(void *))
{
// We do not deallocate before outermost commit, so we should never have
// an existing log entry for a deallocation at the same address. We may
// have an existing entry for a matching allocation, but this is handled
// correctly because both are complementary in that only one of these will
// cause an action at commit or abort.
gtm_alloc_action *a = this->alloc_actions.insert((uintptr_t) ptr);
a->free_fn = free_fn;
a->free_fn_sz = 0;
a->allocated = false;
}
void
gtm_thread::forget_allocation (void *ptr, size_t sz,
void (*free_fn_sz)(void *, size_t))
{
// Same as forget_allocation but with a size.
gtm_alloc_action *a = this->alloc_actions.insert((uintptr_t) ptr);
a->free_fn = 0;
a->free_fn_sz = free_fn_sz;
a->sz = sz;
a->allocated = false;
}
namespace {
struct commit_cb_data {
aa_tree<uintptr_t, gtm_alloc_action>* parent;
bool revert_p;
};
}
static void
commit_allocations_2 (uintptr_t key, gtm_alloc_action *a, void *data)
{
void *ptr = (void *)key;
commit_cb_data *cb_data = static_cast<commit_cb_data *>(data);
if (cb_data->revert_p)
{
// Roll back nested allocations, discard deallocations.
if (a->allocated)
{
if (a->free_fn_sz != 0)
a->free_fn_sz (ptr, a->sz);
else
a->free_fn (ptr);
}
}
else
{
// Add allocations and deallocations to parent.
// ??? We could eliminate a (parent) allocation that matches this
// a deallocation, if we had support for removing all accesses
// to this allocation from the transaction's undo and redo logs
// (otherwise, the parent transaction's undo or redo might write to
// data that is already shared again because of calling free()).
// We don't have this support currently, and the benefit of this
// optimization is unknown, so just add it to the parent.
gtm_alloc_action* a_parent = cb_data->parent->insert(key);
*a_parent = *a;
}
}
static void
commit_allocations_1 (uintptr_t key, gtm_alloc_action *a, void *cb_data)
{
void *ptr = (void *)key;
bool revert_p = (bool) (uintptr_t) cb_data;
if (revert_p == a->allocated)
{
if (a->free_fn_sz != 0)
a->free_fn_sz (ptr, a->sz);
else
a->free_fn (ptr);
}
}
/* Permanently commit allocated memory during transaction.
REVERT_P is true if instead of committing the allocations, we want
to roll them back (and vice versa). */
void
gtm_thread::commit_allocations (bool revert_p,
aa_tree<uintptr_t, gtm_alloc_action>* parent)
{
if (parent)
{
commit_cb_data cb_data;
cb_data.parent = parent;
cb_data.revert_p = revert_p;
this->alloc_actions.traverse (commit_allocations_2, &cb_data);
}
else
this->alloc_actions.traverse (commit_allocations_1,
(void *)(uintptr_t)revert_p);
this->alloc_actions.clear ();
}
} // namespace GTM
|
