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
|
/***************************************************************************
* lib/io/request_queue_impl_1q.cpp
*
* Part of the STXXL. See http://stxxl.sourceforge.net
*
* Copyright (C) 2002-2005 Roman Dementiev <dementiev@mpi-sb.mpg.de>
* Copyright (C) 2009 Andreas Beckmann <beckmann@cs.uni-frankfurt.de>
* Copyright (C) 2009 Johannes Singler <singler@ira.uka.de>
* Copyright (C) 2013 Timo Bingmann <tb@panthema.net>
*
* Distributed under the Boost Software License, Version 1.0.
* (See accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
**************************************************************************/
#include <algorithm>
#include <stxxl/bits/config.h>
#include <stxxl/bits/common/error_handling.h>
#include <stxxl/bits/io/request_queue_impl_1q.h>
#include <stxxl/bits/io/serving_request.h>
#include <stxxl/bits/parallel.h>
#if STXXL_STD_THREADS && STXXL_MSVC >= 1700
#include <windows.h>
#endif
#ifndef STXXL_CHECK_FOR_PENDING_REQUESTS_ON_SUBMISSION
#define STXXL_CHECK_FOR_PENDING_REQUESTS_ON_SUBMISSION 1
#endif
STXXL_BEGIN_NAMESPACE
struct file_offset_match : public std::binary_function<request_ptr, request_ptr, bool>
{
bool operator () (
const request_ptr& a,
const request_ptr& b) const
{
// matching file and offset are enough to cause problems
return (a->get_offset() == b->get_offset()) &&
(a->get_file() == b->get_file());
}
};
request_queue_impl_1q::request_queue_impl_1q(int n)
: m_thread_state(NOT_RUNNING), m_sem(0)
{
STXXL_UNUSED(n);
start_thread(worker, static_cast<void*>(this), m_thread, m_thread_state);
}
void request_queue_impl_1q::add_request(request_ptr& req)
{
if (req.empty())
STXXL_THROW_INVALID_ARGUMENT("Empty request submitted to disk_queue.");
if (m_thread_state() != RUNNING)
STXXL_THROW_INVALID_ARGUMENT("Request submitted to not running queue.");
if (!dynamic_cast<serving_request*>(req.get()))
STXXL_ERRMSG("Incompatible request submitted to running queue.");
#if STXXL_CHECK_FOR_PENDING_REQUESTS_ON_SUBMISSION
{
scoped_mutex_lock Lock(m_queue_mutex);
if (std::find_if(m_queue.begin(), m_queue.end(),
bind2nd(file_offset_match(), req) _STXXL_FORCE_SEQUENTIAL)
!= m_queue.end())
{
STXXL_ERRMSG("request submitted for a BID with a pending request");
}
}
#endif
scoped_mutex_lock Lock(m_queue_mutex);
m_queue.push_back(req);
m_sem++;
}
bool request_queue_impl_1q::cancel_request(request_ptr& req)
{
if (req.empty())
STXXL_THROW_INVALID_ARGUMENT("Empty request canceled disk_queue.");
if (m_thread_state() != RUNNING)
STXXL_THROW_INVALID_ARGUMENT("Request canceled to not running queue.");
if (!dynamic_cast<serving_request*>(req.get()))
STXXL_ERRMSG("Incompatible request submitted to running queue.");
bool was_still_in_queue = false;
{
scoped_mutex_lock Lock(m_queue_mutex);
queue_type::iterator pos
= std::find(m_queue.begin(), m_queue.end(),
req _STXXL_FORCE_SEQUENTIAL);
if (pos != m_queue.end())
{
m_queue.erase(pos);
was_still_in_queue = true;
m_sem--;
}
}
return was_still_in_queue;
}
request_queue_impl_1q::~request_queue_impl_1q()
{
stop_thread(m_thread, m_thread_state, m_sem);
}
void* request_queue_impl_1q::worker(void* arg)
{
self* pthis = static_cast<self*>(arg);
for ( ; ; )
{
pthis->m_sem--;
{
scoped_mutex_lock Lock(pthis->m_queue_mutex);
if (!pthis->m_queue.empty())
{
request_ptr req = pthis->m_queue.front();
pthis->m_queue.pop_front();
Lock.unlock();
//assert(req->nref() > 1);
dynamic_cast<serving_request*>(req.get())->serve();
}
else
{
Lock.unlock();
pthis->m_sem++;
}
}
// terminate if it has been requested and queues are empty
if (pthis->m_thread_state() == TERMINATING) {
if ((pthis->m_sem--) == 0)
break;
else
pthis->m_sem++;
}
}
pthis->m_thread_state.set_to(TERMINATED);
#if STXXL_STD_THREADS && STXXL_MSVC >= 1700
// Workaround for deadlock bug in Visual C++ Runtime 2012 and 2013, see
// request_queue_impl_worker.cpp. -tb
ExitThread(NULL);
#else
return NULL;
#endif
}
STXXL_END_NAMESPACE
// vim: et:ts=4:sw=4
|
