-
Notifications
You must be signed in to change notification settings - Fork 4
Expand file tree
/
Copy pathfam_get.html
More file actions
263 lines (246 loc) · 9.43 KB
/
fam_get.html
File metadata and controls
263 lines (246 loc) · 9.43 KB
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
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
<!DOCTYPE html>
<html lang="en">
<head>
<link rel="stylesheet" type="text/css" href="styles/style.css">
<title>OpenFAM: A library for programming Fabric-Attached Memory</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<header>
<h1>OpenFAM Reference Implementation</h1>
</header>
<section>
<nav>
<ul>
<li><a href="index.html">Home</a></li>
<li><a href="release_notes.html">Release Notes</a></li>
<li><a href="limitations.html">Design Choices</a></li>
<li><a href="errors.html">Exceptions and Error Codes</a></li>
<li><a href="services.html">Services</a></li>
<li><a href="config_files.html">Configuration Files</a></li>
</ul>
<hr>
Initialization and Finalization
<ul>
<li><a href="fam_initialize.html">fam_initialize</a></li>
<li><a href="fam_finalize.html">fam_finalize</a></li>
<li><a href="fam_abort.html">fam_abort</a></li>
</ul>
<hr>
Options & Query
<ul>
<li><a href="fam_list_options.html">fam_list_options</a></li>
<li><a href="fam_get_option.html">fam_get_option</a></li>
<li><a href="fam_lookup.html">fam_lookup</a></li>
<li><a href="fam_stat.html">fam_stat</a></li>
</ul>
<hr>
Memory Allocation
<ul>
<li><a href="fam_create_region.html">fam_create_region</a></li>
<li><a href="fam_destroy_region.html">fam_destroy_region</a></li>
<li><a href="fam_resize_region.html">fam_resize_region</a></li>
<li><a href="fam_allocate.html">fam_allocate</a></li>
<li><a href="fam_deallocate.html">fam_deallocate</a></li>
<li><a href="fam_change_permissions.html">fam_change_permissions</a></li>
<li><a href="fam_close.html">fam_close</a></li>
</ul>
<hr>
Memory Map
<ul>
<li><a href="fam_map.html">fam_map</a></li>
<li><a href="fam_unmap.html">fam_unmap</a></li>
</ul>
<hr>
Data Path Operations
<ul>
<li><a href="fam_get.html">fam_get</a></li>
<li><a href="fam_put.html">fam_put</a></li>
<li><a href="fam_gather.html">fam_gather</a></li>
<li><a href="fam_scatter.html">fam_scatter</a></li>
<li><a href="fam_copy.html">fam_copy</a></li>
<li><a href="fam_copy_wait.html">fam_copy_wait</a></li>
<li><a href="fam_backup.html">fam_backup</a></li>
<li><a href="fam_backup_wait.html">fam_backup_wait</a></li>
<li><a href="fam_restore.html">fam_restore</a></li>
<li><a href="fam_restore_wait.html">fam_restore_wait</a></li>
<li><a href="fam_delete_backup.html">fam_delete_backup</a></li>
<li><a href="fam_delete_backup_wait.html">fam_delete_backup_wait</a></li>
</ul>
<hr>
Atomics
<ul>
<li><a href="fam_set.html">fam_set</a></li>
<li><a href="fam_add.html">fam_add</a></li>
<li><a href="fam_subtract.html">fam_subtract</a></li>
<li><a href="fam_min.html">fam_min</a></li>
<li><a href="fam_max.html">fam_max</a></li>
<li><a href="fam_and.html">fam_and</a></li>
<li><a href="fam_or.html">fam_or</a></li>
<li><a href="fam_xor.html">fam_xor</a></li>
<li><a href="fam_fetch_TYPE.html">fam_fetch_TYPE</a></li>
<li><a href="fam_swap.html">fam_swap</a></li>
<li><a href="fam_compare_swap.html">fam_compare_swap</a></li>
<li><a href="fam_fetch_add.html">fam_fetch_add</a></li>
<li><a href="fam_fetch_subtract.html">fam_fetch_subtract</a></li>
<li><a href="fam_fetch_min.html">fam_fetch_min</a></li>
<li><a href="fam_fetch_and.html">fam_fetch_and</a></li>
<li><a href="fam_fetch_max.html">fam_fetch_max</a></li>
<li><a href="fam_fetch_or.html">fam_fetch_or</a></li>
<li><a href="fam_fetch_xor.html">fam_fetch_xor</a></li>
</ul>
<hr>
Ordering
<ul>
<li><a href="fam_barrier_all.html">fam_barrier_all</a></li>
<li><a href="fam_fence.html">fam_fence</a></li>
<li><a href="fam_quiet.html">fam_quiet</a></li>
<li><a href="fam_progress.html">fam_progress</a></li>
<li><a href="fam_context_open.html">fam_context_open</a></li>
<li><a href="fam_context_close.html">fam_context_close</a></li>
</ul>
<hr>
</nav>
<article>
<h1 class="code">openfam::fam::fam_get</h1>
<p>Copy a segment of memory from FAM to local memory.</p>
<h2>Synopsis</h2>
<p class="code">void fam_get_blocking(void *local, Fam_Descriptor *descriptor,
uint64_t offset, uint64_t nbytes);</p>
<p class="code">void fam_get_nonblocking(void *local, Fam_Descriptor
*descriptor, uint64_t offset, uint64_t nbytes);</p>
<h2>Description</h2>
<p>Copy (part of) some data item from FAM to local memory.</p>
<h2>Input Arguments</h2>
<table>
<tbody>
<tr><th>Name</th><th>Description</th></tr>
<tr>
<td class="code">
local
</td>
<td>
Appropriately sized area of local memory to receive data.
</td>
</tr>
<tr>
<td class="code">
descriptor
</td>
<td>
Descriptor associated with the data item in FAM.
</td>
</tr>
<tr>
<td class="code">
offset
</td>
<td>
Byte offset from the start of the data item in FAM.
</td>
</tr>
<tr>
<td class="code">
nbytes
</td>
<td>
Number of bytes to copy from FAM to local memory.
</td>
</tr>
</tbody>
</table>
<h2>Return Values</h2>
<p>These calls do not return a value on success. Both non-blocking and blocking calls
throw <code>Fam_Exception</code> on error.</p>
<h2>Fam Error Numbers</h2>
<table>
<tbody>
<tr><th>Error</th><th>Description</th></tr>
<tr><td class="code">FAM_ERR_INVALID</td><td>API called with incorrect parameters.</td></tr>
<tr><td class="code">FAM_ERR_NOPERM</td><td>Caller does not have access rights.</td></tr>
<tr><td class="code">FAM_ERR_LIBFABRIC</td><td>Libfabric error occurred.</td></tr>
<tr><td class="code">FAM_ERR_NOTFOUND</td><td>Item not found in the region.</td></tr>
<tr><td class="code">FAM_ERR_RPC</td><td>Communication error from grpc layer.</td></tr>
<tr><td class="code">FAM_ERR_RPC_CLIENT_NOTFOUND</td><td>RPC service not available.</td></tr>
<tr><td class="code">FAM_ERR_METADATA</td><td>Metadata service error.</td></tr>
<tr><td class="code">FAM_ERR_MEMORY</td><td>Memory service error.</td></tr>
<tr><td class="code">FAM_ERR_RESOURCE</td><td>Resource not available.</td></tr>
<tr><td class="code">FAM_ERR_TIMEOUT</td><td>Number of libfabric retry count reached.</td></tr>
</tbody>
</table>
<h2 id="e1">Notes</h2>
<p>The local memory pointer must point to an area of memory
sufficient to accommodate the incoming data (<code>nbytes</code>). Insufficient
allocation of local memory may cause segmentation violations or
corrupted data in local memory.</p>
<p>Upon return, the memory pointed to by local contains a copy of the
data in FAM for the blocking call. For the non-blocking call, the
memory pointed to by the local pointer is not guaranteed to contain a
copy of the data in FAM until after successful completion of a subsequent
<code>fam_quiet()</code> call.</p>
<h2>Examples</h2>
<pre>
// Example of blocking get
#include <string.h>
#include <fam/fam.h>
#include <fam/fam_exception.h>
using namespace std;
using namespace openfam;
int main(void) {
fam *myFam = new fam();
// ... Initialization code here
try {
// look up the descriptor to a previously allocated data item
// (a 50 element integer array)
Fam_Descriptor *descriptor = myFam->fam_lookup("myItem", "myRegion");
// allocate local memory to receive 10 elements
int *local = (int *)malloc(10 * sizeof(int));
// copy elements 6-15 from FAM into elements 0-9 in local memory
myFam->fam_get_blocking(local, descriptor, 6*sizeof(int), 10*sizeof(int));
// ... we now have a copy in local memory to work with
printf("fam_get_blocking success. Data now in local memory\n");
} catch (Fam_Exception &e) {
printf("fam API failed: %d: %s\n", e.fam_error(), e.fam_error_msg());
}
// ... Finalization code
}
// Example of non-blocking get
#include <string.h>
#include <fam/fam.h>
#include <fam/fam_exception.h>
using namespace std;
using namespace openfam;
int main(void) {
fam *myFam = new fam();
// ... Initialization code here
try {
// look up the descriptor to a previously allocated data item
// (a 50 element integer array)
Fam_Descriptor *descriptor1 = myFam->fam_lookup("myItem", "myRegion");
// allocate local memory to receive 10 elements from different offsets
// within the data item
int *local1 = (int *) malloc(10 * sizeof(int));
int *local2 = (int *) malloc(10 * sizeof(int));
// copy elements 6-15 from FAM into local1 elements 0-9 in local memory
myFam->fam_get_nonblocking(local1, descriptor1, 6*sizeof(int), 10*sizeof(int));
// copy elements 26-35 from FAM into local2 elements 0-9 in local memory
myFam->fam_get_nonblocking(local2, descriptor1, 26*sizeof(int), 10*sizeof(int));
// wait for previously issued non-blocking operations to complete
myFam->fam_quiet();
// ... we now have copies in local memory to work with
printf("fam_get_nonblocking success. All copies of data now in local
memory\n");
} catch (Fam_Exception &e) {
printf("fam API failed: %d: %s\n", e.fam_error(), e.fam_error_msg());
}
// ... Finalization code follows
}
</pre>
</article>
</section>
<footer>
<p>Copyright 2021-23, Hewlett Packard Enterprise Development Co, LLP</p>
</footer>
</body>
</html>