ubtunu20.04 opencl 安装

ubtunu20.04 opencl 安装

1 安装

其实CUDA安装是包含了OPENCL的，但是你要使用OPENCL还需要配置一下。
也可以单独安装头文件和库

sudo apt install opencl-headers 
sudo apt install ocl-icd-libopencl1 
sudo apt install ocl-icd-opencl-dev
sudo apt install clinfo
#sudo apt install intel-opencl-icd  #Install NEO OpenCL runtime for Intel GPU

查看电脑当前安装信息

root@peter-B760M-GAMING-AC-DDR4:/home/peter# clinfo
Number of platforms                               1
  Platform Name                                   NVIDIA CUDA
  Platform Vendor                                 NVIDIA Corporation
  Platform Version                                OpenCL 3.0 CUDA 12.1.68
  Platform Profile                                FULL_PROFILE
  Platform Extensions                             cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_fp64 cl_khr_3d_image_writes cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing cl_nv_compiler_options cl_nv_device_attribute_query cl_nv_pragma_unroll cl_nv_copy_opts cl_nv_create_buffer cl_khr_int64_base_atomics cl_khr_int64_extended_atomics cl_khr_device_uuid cl_khr_pci_bus_info cl_khr_external_semaphore cl_khr_external_memory cl_khr_external_semaphore_opaque_fd cl_khr_external_memory_opaque_fd
  Platform Host timer resolution                  0ns
  Platform Extensions function suffix             NV

  Platform Name                                   NVIDIA CUDA
Number of devices                                 1
  Device Name                                     NVIDIA GeForce RTX 3060 Ti
  Device Vendor                                   NVIDIA Corporation
  Device Vendor ID                                0x10de
  Device Version                                  OpenCL 3.0 CUDA

2 测试oepncl

#include   
#include   
#include   
 
#ifdef MAC  
#include   
#else  
#include   
#endif  
 
int main() {  
 
    /* Host data structures */  
    cl_platform_id *platforms;  
    //每一个cl_platform_id 结构表示一个在主机上的OpenCL执行平台，就是指电脑中支持OpenCL的硬件，如nvidia显卡，intel CPU和显卡，AMD显卡和CPU等  
    cl_uint num_platforms;  
    cl_int i, err, platform_index = -1;  
 
    /* Extension data */  
    char* ext_data;                           
    size_t ext_size;     
    const char icd_ext[] = "cl_khr_icd";  
 
    //要使platform工作，需要两个步骤。1 需要为cl_platform_id结构分配内存空间。2 需要调用clGetPlatformIDs初始化这些数据结构。一般还需要步骤0：询问主机上有多少platforms  
 
    /* Find number of platforms */  
    //返回值如果为-1就说明调用函数失败，如果为0标明成功  
    //第二个参数为NULL代表要咨询主机上有多少个platform，并使用num_platforms取得实际flatform数量。  
    //第一个参数为1，代表我们需要取最多1个platform。可以改为任意大如：INT_MAX整数最大值。但是据说0，否则会报错，实际测试好像不会报错。下面是步骤0：询问主机有多少platforms  
    err = clGetPlatformIDs(5, NULL, &num_platforms);          
    if(err < 0) {          
        perror("Couldn't find any platforms.");           
        exit(1);                              
    }                                     
 
    printf("I have platforms: %d\n", num_platforms); //本人计算机上显示为2，有intel和nvidia两个平台  
 
    /* Access all installed platforms */  
    //步骤1 创建cl_platform_id，并分配空间  
    platforms = (cl_platform_id*)                     
        malloc(sizeof(cl_platform_id) * num_platforms);   
    //步骤2 第二个参数用指针platforms存储platform  
    clGetPlatformIDs(num_platforms, platforms, NULL);         
 
    /* Find extensions of all platforms */  
    //获取额外的平台信息。上面已经取得了平台id了，那么就可以进一步获取更加详细的信息了。  
    //一个for循环获取所有的主机上的platforms信息  
    for(i=0; i<num_platforms; i++)   
    {  
        /* Find size of extension data */  
        //也是和前面一样，先设置第三和第四个参数为0和NULL，然后就可以用第五个参数ext_size获取额外信息的长度了。  
        err = clGetPlatformInfo(platforms[i],             
            CL_PLATFORM_EXTENSIONS, 0, NULL, &ext_size);      
        if(err < 0)   
        {  
            perror("Couldn't read extension data.");              
            exit(1);  
        }     
 
        printf("The size of extension data is: %d\n", (int)ext_size);//我的计算机显示224.  
 
        /* Access extension data */    
        //这里的ext_data相当于一个缓存，存储相关信息。  
        ext_data = (char*)malloc(ext_size);   
        //这个函数就是获取相关信息的函数，第二个参数指明了需要什么样的信息，如这里的CL_PLATFORM_EXTENSIONS表示是opencl支持的扩展功能信息。我计算机输出一大串，机器比较新（专门为了学图形学而购置的电脑），支持的东西比较多。  
        clGetPlatformInfo(platforms[i], CL_PLATFORM_EXTENSIONS,       
            ext_size, ext_data, NULL);                
        printf("Platform %d supports extensions: %s\n", i, ext_data);  
 
        //这里是输出生产商的名字，比如我显卡信息是：NVIDIA CUDA  
        char *name = (char*)malloc(ext_size);  
        clGetPlatformInfo(platforms[i], CL_PLATFORM_NAME,     
            ext_size, name, NULL);                
        printf("Platform %d name: %s\n", i, name);  
 
        //这里是供应商信息，我显卡信息：NVIDIA Corporation  
        char *vendor = (char*)malloc(ext_size);  
        clGetPlatformInfo(platforms[i], CL_PLATFORM_VENDOR,       
            ext_size, vendor, NULL);                  
        printf("Platform %d vendor: %s\n", i, vendor);  
 
        //最高支持的OpenCL版本，本机显示：OpenCL1.1 CUDA 4.2.1  
        char *version = (char*)malloc(ext_size);  
        clGetPlatformInfo(platforms[i], CL_PLATFORM_VERSION,      
            ext_size, version, NULL);                 
        printf("Platform %d version: %s\n", i, version);  
 
        //这个只有两个值：full profile 和 embeded profile  
        char *profile = (char*)malloc(ext_size);  
        clGetPlatformInfo(platforms[i], CL_PLATFORM_PROFILE,      
            ext_size, profile, NULL);                 
        printf("Platform %d full profile or embeded profile?: %s\n", i, profile);  
 
        /* Look for ICD extension */     
        //如果支持ICD这一扩展功能的platform，输出显示，本机的Intel和Nvidia都支持这一扩展功能  
        if(strstr(ext_data, icd_ext) != NULL)   
            platform_index = i;  
        //std::cout<<"Platform_index = "<
        printf("Platform_index is: %d\n", platform_index);  
        /* Display whether ICD extension is supported */  
        if(platform_index > -1)  
            printf("Platform %d supports the %s extension.\n",   
            platform_index, icd_ext);  
 
 
        //释放空间  
        free(ext_data);  
        free(name);  
        free(vendor);  
        free(version);  
        free(profile);  
    }  
 
    if(platform_index <= -1)  
        printf("No platforms support the %s extension.\n", icd_ext);  
 
    /* Deallocate resources */  
    free(platforms);  
    return 0;  
}   

用gcc编译以上程序

gcc opencl_hello.c -o opencl_hello -lOpenCL

若有类似如下输出，则表示opencl配置正确：

root@peter-B760M-GAMING-AC-DDR4:/home/peter# ./opencl_hello 
I have platforms: 1
The size of extension data is: 553
Platform 0 supports extensions: cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_fp64 cl_khr_3d_image_writes cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing cl_nv_compiler_options cl_nv_device_attribute_query cl_nv_pragma_unroll cl_nv_copy_opts cl_nv_create_buffer cl_khr_int64_base_atomics cl_khr_int64_extended_atomics cl_khr_device_uuid cl_khr_pci_bus_info cl_khr_external_semaphore cl_khr_external_memory cl_khr_external_semaphore_opaque_fd cl_khr_external_memory_opaque_fd
Platform 0 name: NVIDIA CUDA
Platform 0 vendor: NVIDIA Corporation
Platform 0 version: OpenCL 3.0 CUDA 12.1.68
Platform 0 full profile or embeded profile?: FULL_PROFILE
Platform_index is: 0
Platform 0 supports the cl_khr_icd extension.
root@peter-B760M-GAMING-AC-DDR4:/home/peter#