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
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
//
// Copyright 2011-2012 Ettus Research LLC
//
// This program 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.
//
// This program 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.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
#include <uhd/transport/usb_zero_copy.hpp>
#include <uhd/transport/bounded_buffer.hpp>
#include <uhd/transport/buffer_pool.hpp>
#include <uhd/utils/byteswap.hpp>
#include <uhd/utils/msg.hpp>
#include <boost/foreach.hpp>
#include <vector>
#include <iostream>
using namespace uhd::transport;
/***********************************************************************
* USB zero copy wrapper - managed receive buffer
**********************************************************************/
class usb_zero_copy_wrapper_mrb : public managed_recv_buffer{
public:
usb_zero_copy_wrapper_mrb(bounded_buffer<usb_zero_copy_wrapper_mrb *> &queue):
_queue(queue){/*NOP*/}
void release(void){
if (_mrb.get() == NULL) return;
_mrb->release();
_queue.push_with_haste(this);
_mrb.reset();
}
UHD_INLINE sptr get_new(managed_recv_buffer::sptr mrb, const void *mem, size_t len){
_mrb = mrb;
_mem = mem;
_len = len;
return make_managed_buffer(this);
}
private:
const void *get_buff(void) const{return _mem;}
size_t get_size(void) const{return _len;}
bounded_buffer<usb_zero_copy_wrapper_mrb *> &_queue;
const void *_mem;
size_t _len;
managed_recv_buffer::sptr _mrb;
};
/***********************************************************************
* USB zero copy wrapper - managed send buffer
**********************************************************************/
class usb_zero_copy_wrapper_msb : public managed_send_buffer{
public:
usb_zero_copy_wrapper_msb(const usb_zero_copy::sptr internal, const size_t fragmentation_size):
_internal(internal), _fragmentation_size(fragmentation_size){/*NOP*/}
void commit(size_t len){
if (len == 0) return;
//get a reference to the VITA header before incrementing
const boost::uint32_t vita_header = reinterpret_cast<const boost::uint32_t *>(_mem_buffer_tip)[0];
_bytes_in_buffer += len;
_mem_buffer_tip += len;
//extract VITA end of packet flag, we must force flush under eof conditions
const bool eop = (uhd::wtohx(vita_header) & (0x1 << 24)) != 0;
const bool full = _bytes_in_buffer >= (_last_send_buff->size() - _fragmentation_size);
if (eop or full){
_last_send_buff->commit(_bytes_in_buffer);
_last_send_buff.reset();
}
}
UHD_INLINE sptr get_new(const double timeout){
if (not _last_send_buff){
_last_send_buff = _internal->get_send_buff(timeout);
if (not _last_send_buff) return sptr();
_mem_buffer_tip = _last_send_buff->cast<char *>();
_bytes_in_buffer = 0;
}
return make_managed_buffer(this);
}
private:
void *get_buff(void) const{return reinterpret_cast<void *>(_mem_buffer_tip);}
size_t get_size(void) const{return _fragmentation_size;}
usb_zero_copy::sptr _internal;
const size_t _fragmentation_size;
managed_send_buffer::sptr _last_send_buff;
size_t _bytes_in_buffer;
char *_mem_buffer_tip;
};
/***********************************************************************
* USB zero copy wrapper implementation
**********************************************************************/
class usb_zero_copy_wrapper : public usb_zero_copy{
public:
usb_zero_copy_wrapper(sptr usb_zc, const size_t frame_boundary):
_internal_zc(usb_zc),
_frame_boundary(frame_boundary),
_available_recv_buffs(this->get_num_recv_frames()),
_mrb_pool(this->get_num_recv_frames(), usb_zero_copy_wrapper_mrb(_available_recv_buffs)),
_the_only_msb(usb_zero_copy_wrapper_msb(usb_zc, frame_boundary))
{
BOOST_FOREACH(usb_zero_copy_wrapper_mrb &mrb, _mrb_pool){
_available_recv_buffs.push_with_haste(&mrb);
}
}
managed_recv_buffer::sptr get_recv_buff(double timeout){
//attempt to get a managed recv buffer
if (not _last_recv_buff.get()){
_last_recv_buff = _internal_zc->get_recv_buff(timeout);
_last_recv_offset = 0;
}
//attempt to get a wrapper for a managed recv buffer
usb_zero_copy_wrapper_mrb *wmrb = NULL;
if (_last_recv_buff.get() and _available_recv_buffs.pop_with_timed_wait(wmrb, timeout)){
//extract this packet's memory address and length in bytes
const char *mem = _last_recv_buff->cast<const char *>() + _last_recv_offset;
const boost::uint32_t *mem32 = reinterpret_cast<const boost::uint32_t *>(mem);
const size_t len = (uhd::wtohx(mem32[0]) & 0xffff)*sizeof(boost::uint32_t); //length in bytes (from VRT header)
managed_recv_buffer::sptr recv_buff; //the buffer to be returned to the user
recv_buff = wmrb->get_new(_last_recv_buff, mem, len);
_last_recv_offset += len;
//check if this receive buffer has been exhausted
if (_last_recv_offset >= _last_recv_buff->size()) {
_last_recv_buff.reset();
}
return recv_buff;
}
//otherwise return a null sptr for failure
return managed_recv_buffer::sptr();
}
size_t get_num_recv_frames(void) const{
return _internal_zc->get_num_recv_frames();
}
size_t get_recv_frame_size(void) const{
return std::min(_frame_boundary, _internal_zc->get_recv_frame_size());
}
managed_send_buffer::sptr get_send_buff(double timeout){
return _the_only_msb.get_new(timeout);
}
size_t get_num_send_frames(void) const{
return _internal_zc->get_num_send_frames();
}
size_t get_send_frame_size(void) const{
return std::min(_frame_boundary, _internal_zc->get_send_frame_size());
}
private:
sptr _internal_zc;
size_t _frame_boundary;
bounded_buffer<usb_zero_copy_wrapper_mrb *> _available_recv_buffs;
std::vector<usb_zero_copy_wrapper_mrb> _mrb_pool;
usb_zero_copy_wrapper_msb _the_only_msb;
//buffer to store partially-received VRT packets in
buffer_pool::sptr _fragment_mem;
//state for last recv buffer to create multiple managed buffers
managed_recv_buffer::sptr _last_recv_buff;
size_t _last_recv_offset;
};
/***********************************************************************
* USB zero copy wrapper factory function
**********************************************************************/
usb_zero_copy::sptr usb_zero_copy::make_wrapper(
sptr usb_zc, size_t usb_frame_boundary
){
return sptr(new usb_zero_copy_wrapper(usb_zc, usb_frame_boundary));
}
|
