1//===- NVPTXArch.cpp - list installed NVPTX devies ------*- C++ -*---------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements a tool for detecting name of CUDA gpus installed in the
10// system.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Basic/Version.h"
15#include "llvm/Support/CommandLine.h"
16#include "llvm/Support/DynamicLibrary.h"
17#include "llvm/Support/Error.h"
18#include <cstdint>
19#include <cstdio>
20#include <memory>
21
22using namespace llvm;
23
24static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
25
26static void PrintVersion(raw_ostream &OS) {
27  OS << clang::getClangToolFullVersion("nvptx-arch") << '\n';
28}
29// Mark all our options with this category, everything else (except for -version
30// and -help) will be hidden.
31static cl::OptionCategory NVPTXArchCategory("nvptx-arch options");
32
33typedef enum cudaError_enum {
34  CUDA_SUCCESS = 0,
35  CUDA_ERROR_NO_DEVICE = 100,
36} CUresult;
37
38typedef enum CUdevice_attribute_enum {
39  CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MAJOR = 75,
40  CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MINOR = 76,
41} CUdevice_attribute;
42
43typedef uint32_t CUdevice;
44
45CUresult (*cuInit)(unsigned int);
46CUresult (*cuDeviceGetCount)(int *);
47CUresult (*cuGetErrorString)(CUresult, const char **);
48CUresult (*cuDeviceGet)(CUdevice *, int);
49CUresult (*cuDeviceGetAttribute)(int *, CUdevice_attribute, CUdevice);
50
51constexpr const char *DynamicCudaPath = "libcuda.so.1";
52
53llvm::Error loadCUDA() {
54  std::string ErrMsg;
55  auto DynlibHandle = std::make_unique<llvm::sys::DynamicLibrary>(
56      llvm::sys::DynamicLibrary::getPermanentLibrary(DynamicCudaPath, &ErrMsg));
57  if (!DynlibHandle->isValid()) {
58    return llvm::createStringError(llvm::inconvertibleErrorCode(),
59                                   "Failed to 'dlopen' %s", DynamicCudaPath);
60  }
61#define DYNAMIC_INIT(SYMBOL)                                                   \
62  {                                                                            \
63    void *SymbolPtr = DynlibHandle->getAddressOfSymbol(#SYMBOL);               \
64    if (!SymbolPtr)                                                            \
65      return llvm::createStringError(llvm::inconvertibleErrorCode(),           \
66                                     "Failed to 'dlsym' " #SYMBOL);            \
67    SYMBOL = reinterpret_cast<decltype(SYMBOL)>(SymbolPtr);                    \
68  }
69  DYNAMIC_INIT(cuInit);
70  DYNAMIC_INIT(cuDeviceGetCount);
71  DYNAMIC_INIT(cuGetErrorString);
72  DYNAMIC_INIT(cuDeviceGet);
73  DYNAMIC_INIT(cuDeviceGetAttribute);
74#undef DYNAMIC_INIT
75  return llvm::Error::success();
76}
77
78static int handleError(CUresult Err) {
79  const char *ErrStr = nullptr;
80  CUresult Result = cuGetErrorString(Err, &ErrStr);
81  if (Result != CUDA_SUCCESS)
82    return 1;
83  fprintf(stderr, "CUDA error: %s\n", ErrStr);
84  return 1;
85}
86
87int main(int argc, char *argv[]) {
88  cl::HideUnrelatedOptions(NVPTXArchCategory);
89
90  cl::SetVersionPrinter(PrintVersion);
91  cl::ParseCommandLineOptions(
92      argc, argv,
93      "A tool to detect the presence of NVIDIA devices on the system. \n\n"
94      "The tool will output each detected GPU architecture separated by a\n"
95      "newline character. If multiple GPUs of the same architecture are found\n"
96      "a string will be printed for each\n");
97
98  if (Help) {
99    cl::PrintHelpMessage();
100    return 0;
101  }
102
103  // Attempt to load the NVPTX driver runtime.
104  if (llvm::Error Err = loadCUDA()) {
105    logAllUnhandledErrors(std::move(Err), llvm::errs());
106    return 1;
107  }
108
109  if (CUresult Err = cuInit(0)) {
110    if (Err == CUDA_ERROR_NO_DEVICE)
111      return 0;
112    else
113      return handleError(Err);
114  }
115
116  int Count = 0;
117  if (CUresult Err = cuDeviceGetCount(&Count))
118    return handleError(Err);
119  if (Count == 0)
120    return 0;
121  for (int DeviceId = 0; DeviceId < Count; ++DeviceId) {
122    CUdevice Device;
123    if (CUresult Err = cuDeviceGet(&Device, DeviceId))
124      return handleError(Err);
125
126    int32_t Major, Minor;
127    if (CUresult Err = cuDeviceGetAttribute(
128            &Major, CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MAJOR, Device))
129      return handleError(Err);
130    if (CUresult Err = cuDeviceGetAttribute(
131            &Minor, CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MINOR, Device))
132      return handleError(Err);
133
134    printf("sm_%d%d\n", Major, Minor);
135  }
136  return 0;
137}
138