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cuda.h
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1 /*
2 * Copyright © 2010 inria. All rights reserved.
3 * Copyright © 2010 Université Bordeaux 1
4 * Copyright © 2011 Cisco Systems, Inc. All rights reserved.
5 * See COPYING in top-level directory.
6 */
7
8 /** \file
9 * \brief Macros to help interaction between hwloc and the CUDA Driver API.
10 *
11 * Applications that use both hwloc and the CUDA Driver API may want to
12 * include this file so as to get topology information for CUDA devices.
13 *
14 */
15
16 #ifndef HWLOC_CUDA_H
17 #define HWLOC_CUDA_H
18
19 #include <hwloc.h>
20 #include <hwloc/autogen/config.h>
21 #include <hwloc/linux.h>
22
23 #include <cuda.h>
24
25
26 #ifdef __cplusplus
27 extern "C" {
28 #endif
29
30
31 /** \defgroup hwlocality_cuda CUDA Driver API Specific Functions
32 * @{
33 */
34
35 /** \brief Get the CPU set of logical processors that are physically
36 * close to device \p cudevice.
37 *
38 * For the given CUDA Driver API device \p cudevice, read the corresponding
39 * kernel-provided cpumap file and return the corresponding CPU set.
40 * This function is currently only implemented in a meaningful way for
41 * Linux; other systems will simply get a full cpuset.
42 */
43 static __hwloc_inline int
44 hwloc_cuda_get_device_cpuset(hwloc_topology_t topology __hwloc_attribute_unused,
45 CUdevice cudevice, hwloc_cpuset_t set)
46 {
47 #ifdef HWLOC_LINUX_SYS
48 /* If we're on Linux, use the sysfs mechanism to get the local cpus */
49 #define HWLOC_CUDA_DEVICE_SYSFS_PATH_MAX 128
50 CUresult cres;
51 int domainid = 0;
52 int deviceid;
53 int busid;
54 char path[HWLOC_CUDA_DEVICE_SYSFS_PATH_MAX];
55 FILE *sysfile = NULL;
56
57 #if CUDA_VERSION >= 4000
58 cres = cuDeviceGetAttribute(&domainid, CU_DEVICE_ATTRIBUTE_PCI_DOMAIN_ID, cudevice);
59 if (cres != CUDA_SUCCESS) {
60 errno = ENOSYS;
61 return -1;
62 }
63 #endif
64 cres = cuDeviceGetAttribute(&busid, CU_DEVICE_ATTRIBUTE_PCI_BUS_ID, cudevice);
65 if (cres != CUDA_SUCCESS) {
66 errno = ENOSYS;
67 return -1;
68 }
69 cres = cuDeviceGetAttribute(&deviceid, CU_DEVICE_ATTRIBUTE_PCI_DEVICE_ID, cudevice);
70 if (cres != CUDA_SUCCESS) {
71 errno = ENOSYS;
72 return -1;
73 }
74
75 sprintf(path, "/sys/bus/pci/devices/%04x:%02x:%02x.0/local_cpus", domainid, busid, deviceid);
76 sysfile = fopen(path, "r");
77 if (!sysfile)
78 return -1;
79
80 hwloc_linux_parse_cpumap_file(sysfile, set);
81
82 fclose(sysfile);
83 #else
84 /* Non-Linux systems simply get a full cpuset */
85 hwloc_bitmap_copy(set, hwloc_topology_get_complete_cpuset(topology));
86 #endif
87 return 0;
88 }
89
90 /** @} */
91
92
93 #ifdef __cplusplus
94 } /* extern "C" */
95 #endif
96
97
98 #endif /* HWLOC_CUDA_H */
hwloc_bitmap_copy
HWLOC_DECLSPEC void hwloc_bitmap_copy(hwloc_bitmap_t dst, hwloc_const_bitmap_t src)
Copy the contents of bitmap src into the already allocated bitmap dst.
hwloc_topology_get_complete_cpuset
static __hwloc_inline hwloc_const_cpuset_t __hwloc_attribute_pure hwloc_topology_get_complete_cpuset(hwloc_topology_t topology)
Get complete CPU set.
Definition: helper.h:729
linux.h
Macros to help interaction between hwloc and Linux.
hwloc_linux_parse_cpumap_file
HWLOC_DECLSPEC int hwloc_linux_parse_cpumap_file(FILE *file, hwloc_cpuset_t set)
Convert a linux kernel cpumap file file into hwloc CPU set.
Definition: topology-linux.c:1332
cuda.h
Macros to help interaction between hwloc and the CUDA Driver API.
hwloc_cuda_get_device_cpuset
static __hwloc_inline int hwloc_cuda_get_device_cpuset(hwloc_topology_t topology __hwloc_attribute_unused, CUdevice cudevice, hwloc_cpuset_t set)
Get the CPU set of logical processors that are physically close to device cudevice.
Definition: cuda.h:44
hwloc_topology
Definition: private.h:56
hwloc_bitmap_s
Definition: cpuset.c:38