What nou is saying is correct.
Please refer section 6.7.1 in OpenCL spec.
I am pasting it for your convenience.
The __kernel (or kernel) qualifier declares a function to be a kernel that can be executed by an application on an OpenCL device(s). The following rules apply to functions that are declared with this qualifier: It can be executed on the device only It can be called by the host It is just a regular function call if a __kernel function is called by another kernel function. |