Kernel Configuration#

kernel_param Class Template#

kernel_param is a generic structure for configuring SYCL* kernels. Each kernel template is invoked with a kernel_param type or object. Typically, a kernel template supports multiple values for the configuration parameters. Optimal values may depend on the invoked kernel, the data size and type(s), as well as on the used device.

A synopsis of the kernel_param struct is provided below:

// defined in <oneapi/dpl/experimental/kernel_templates>

namespace oneapi::dpl::experimental::kt {

template <std::uint16_t DataPerWorkItem,
          std::uint16_t WorkGroupSize,
          typename KernelName = /*unspecified*/>
struct kernel_param;

}

Static Member Constants#

Name

Value

Description

static constexpr std::uint16_t data_per_workitem

DataPerWorkItem

The number of iterations to be processed by a work-item.

static constexpr std::uint16_t workgroup_size

WorkGroupSize

The number of work-items within a work-group.

Note

The data_per_workitem parameter has a special meaning in ESIMD-based kernel templates. Usually, each work-item processes data_per_workitem input elements sequentially. However, work-items in ESIMD-based kernel templates perform vectorization, so the sequential work is data_per_workitem / vector_length elements, where vector_length is an implementation-defined vectorization factor.

Member Types#

Type

Definition

Description

kernel_name

KernelName

An optional parameter that is used to set a kernel name.

Note

The KernelName parameter might be required in case an implementation of SYCL is not fully compliant with the SYCL 2020 Specification and does not support optional kernel names.

If omitted, SYCL kernel name(s) will be automatically generated.

If provided, it must be a unique C++ typename that satisfies the requirements for SYCL kernel names in the SYCL 2020 Specification.

Note

The provided name can be augmented by oneDPL when used with a template that creates multiple SYCL kernels.