OpenCL 1.0 Specification阅读笔记（1）

http://www.khronos.org/registry/cl/

4. The OpenCL Platform Layer

implement platform-specific features:

(1) Querying Platform Info

clGetPlatformIDs: define cl_platform_id platforms[num_entries]

clGetPlatformInfo: CL_PLATFORM_EXTENSIONS will return more than 128 characters (NV)

(2) Querying Devices

clGetDeviceIDs:

clGetDeviceInfo: a long list of param name

(3) Contexts

An OpenCL context is created with one or *more* devices, and used by OpenCL runtime for managing objects such as command-queues, memory, program and kernel objects and for executing kernels on one or *more* devices specified in the context.

clCreateContext:

clCreateContextFromType:

注意：

使用clCreateContext函数之前，需要clGetPlatformIDs和clGetDeviceIDs，在clCreateContext中指定DeviceID即可。

使用clCreateContextFromType函数，需要clGetPlatformIDs，并使用cl_context_properties参数传递给clCreateContextFromType。如：

cl_context_properties props[] = {CL_CONTEXT_PLATFORM, (cl_context_properties)cpPlatform, 0};

cl_context GPUContext = clCreateContextFromType( props, CL_DEVICE_TYPE_GPU, NULL, NULL, &error );

clRetainContext: increments context reference count (clCreateContext & clCreateContextFromType already increase it)

clReleaseContext: decrements context reference count

clGetContextInfo:

最重要的就是DeviceInfo列表中的内容，要用专门一节来学习