1 /*
2 * Copyright © 2012 Blue Brain Project, EPFL. All rights reserved.
3 * Copyright © 2012-2013 Inria. All rights reserved.
4 * See COPYING in top-level directory.
5 */
6
7 /** \file
8 * \brief Macros to help interaction between hwloc and OpenGL displays.
9 *
10 * Applications that use both hwloc and OpenGL may want to include
11 * this file so as to get topology information for OpenGL displays.
12 */
13
14 #ifndef HWLOC_GL_H
15 #define HWLOC_GL_H
16
17 #include <hwloc.h>
18
19 #include <stdio.h>
20 #include <string.h>
21
22
23 #ifdef __cplusplus
24 extern "C" {
25 #endif
26
27
28 /** \defgroup hwlocality_gl Interoperability with OpenGL displays
29 *
30 * This interface offers ways to retrieve topology information about
31 * OpenGL displays.
32 *
33 * Only the NVIDIA display locality information is currently available,
34 * using the NV-CONTROL X11 extension and the NVCtrl library.
35 *
36 * @{
37 */
38
39 /** \brief Get the hwloc OS device object corresponding to the
40 * OpenGL display given by port and device index.
41 *
42 * Return the OS device object describing the OpenGL display
43 * whose port (server) is \p port and device (screen) is \p device.
44 * Return NULL if there is none.
45 *
46 * The topology \p topology does not necessarily have to match the current
47 * machine. For instance the topology may be an XML import of a remote host.
48 * I/O devices detection and the GL component must be enabled in the topology.
49 *
50 * \note The corresponding PCI device object can be obtained by looking
51 * at the OS device parent object (unless PCI devices are filtered out).
52 */
53 static __hwloc_inline hwloc_obj_t
54 hwloc_gl_get_display_osdev_by_port_device(hwloc_topology_t topology,
55 unsigned port, unsigned device)
56 {
57 unsigned x = (unsigned) -1, y = (unsigned) -1;
58 hwloc_obj_t osdev = NULL;
59 while ((osdev = hwloc_get_next_osdev(topology, osdev)) != NULL) {
60 if (HWLOC_OBJ_OSDEV_GPU == osdev->attr->osdev.type
61 && osdev->name
62 && sscanf(osdev->name, ":%u.%u", &x, &y) == 2
63 && port == x && device == y)
64 return osdev;
65 }
66 errno = EINVAL;
67 return NULL;
68 }
69
70 /** \brief Get the hwloc OS device object corresponding to the
71 * OpenGL display given by name.
72 *
73 * Return the OS device object describing the OpenGL display
74 * whose name is \p name, built as ":port.device" such as ":0.0" .
75 * Return NULL if there is none.
76 *
77 * The topology \p topology does not necessarily have to match the current
78 * machine. For instance the topology may be an XML import of a remote host.
79 * I/O devices detection and the GL component must be enabled in the topology.
80 *
81 * \note The corresponding PCI device object can be obtained by looking
82 * at the OS device parent object (unless PCI devices are filtered out).
83 */
84 static __hwloc_inline hwloc_obj_t
85 hwloc_gl_get_display_osdev_by_name(hwloc_topology_t topology,
86 const char *name)
87 {
88 hwloc_obj_t osdev = NULL;
89 while ((osdev = hwloc_get_next_osdev(topology, osdev)) != NULL) {
90 if (HWLOC_OBJ_OSDEV_GPU == osdev->attr->osdev.type
91 && osdev->name
92 && !strcmp(name, osdev->name))
93 return osdev;
94 }
95 errno = EINVAL;
96 return NULL;
97 }
98
99 /** \brief Get the OpenGL display port and device corresponding
100 * to the given hwloc OS object.
101 *
102 * Return the OpenGL display port (server) in \p port and device (screen)
103 * in \p screen that correspond to the given hwloc OS device object.
104 * Return \c -1 if there is none.
105 *
106 * The topology \p topology does not necessarily have to match the current
107 * machine. For instance the topology may be an XML import of a remote host.
108 * I/O devices detection and the GL component must be enabled in the topology.
109 */
110 static __hwloc_inline int
111 hwloc_gl_get_display_by_osdev(hwloc_topology_t topology __hwloc_attribute_unused,
112 hwloc_obj_t osdev,
113 unsigned *port, unsigned *device)
114 {
115 unsigned x = -1, y = -1;
116 if (HWLOC_OBJ_OSDEV_GPU == osdev->attr->osdev.type
117 && sscanf(osdev->name, ":%u.%u", &x, &y) == 2) {
118 *port = x;
119 *device = y;
120 return 0;
121 }
122 errno = EINVAL;
123 return -1;
124 }
125
126 /** @} */
127
128
129 #ifdef __cplusplus
130 } /* extern "C" */
131 #endif
132
133
134 #endif /* HWLOC_GL_H */
135