Using Compute Unit Name to Get Handle of All Asymmetrical Compute Units - 2022.2 English

If a kernel instantiates multiple CUs that are not symmetrical, the clCreateKernel command can be specified with CU names to create different CU groups. In this case, the host program can reference a specific CU group by using the cl_kernel handle returned by clCreateKernel.

In the following example, the kernel mykernel has five CUs: K1, K2, K3, K4, and K5. The K1, K2, and K3 CUs are a symmetrical group, having symmetrical connection on the device. Similarly, CUs K4 and K5 form a second symmetrical CU group. The following code segment shows how to address a specific CU group using cl_kernel handles.

// Kernel handle for Symmetrical compute unit group 1: K1,K2,K3
cl_kernel kernelA = clCreateKernel(program,"mykernel:{K1,K2,K3}",&err);

for(i=0; i<3; i++) {
  // Creating buffers for the kernel_handle1
  .....
  // Setting kernel arguments for kernel_handle1
  .....
  // Enqueue buffers for the kernel_handle1
  .....
  // Possible candidates of the executions K1,K2 or K3
  clEnqueueTask(commands, kernelA, 0, NULL, NULL); 
  //
}

// Kernel handle for Symmetrical compute unit group 1: K4, K5
cl_kernel kernelB = clCreateKernel(program,"mykernel:{K4,K5}",&err);

for(int i=0; i<2; i++) {
  // Creating buffers for the kernel_handle2
  .....
  // Setting kernel arguments for kernel_handle2
  .....
  // Enqueue buffers for the kernel_handle2
  .....
  // Possible candidates of the executions K4 or K5
  clEnqueueTask(commands, kernelB, 0, NULL, NULL);
}