Returns information about the kernel object that may be specific to a device.
cl_int
clGetKernelWorkGroupInfo
(
| cl_kernel kernel, |
cl_device_id device, | |
cl_kernel_work_group_info param_name, | |
size_t param_value_size, | |
void *param_value, | |
size_t *param_value_size_ret) |
kernel
Specifies the kernel object being queried.
device
Identifies a specific device in the list of devices associated with kernel
. The list of devices
is the list of devices in the OpenCL context that is associated with kernel
. If the list of devices
associated with kernel
is a single device, device
can be a NULL value.
param_name
Specifies the information to query. The list of supported param_name
types and the
information returned in param_value
by clGetKernelWorkGroupInfo
is described in the table below.
param_value
A pointer to memory where the appropriate result being queried is returned. If param_value
is NULL, it is ignored.
param_value_size
Used to specify the size in bytes of memory pointed to by param_value
.
This size must be greater than or equal to size of return type as described in the table below.
cl_kernel_work_group_info | Return Type | Info. returned in param_value |
---|---|---|
CL_KERNEL_WORK_GROUP_SIZE
|
size_t |
This provides a mechanism for the
application to query the maximum work-group size
that can be used to execute a kernel on a
specific device given by device . The
OpenCL implementation uses the
resource requirements of the kernel
(register usage etc.) to determine what
this work-group size should be.
|
CL_KERNEL_COMPILE_WORK_GROUP_SIZE
|
size_t[3] |
Returns the work-group size specified
by the __attribute__((reqd_work_gr
oup_size(X, Y, Z))) qualifier.
See Function Qualifiers.
If the work-group size is not specified
using the above attribute qualifier (0, 0,
0) is returned.
|
CL_KERNEL_LOCAL_MEM_SIZE
|
cl_ulong |
Returns the amount of local memory in bytes being used by a kernel. This includes local memory that may be needed by an implementation to execute the kernel, variables declared inside the kernel with the __local address qualifier and local memory to be allocated for arguments to the kernel declared as pointers with the __local address qualifier and whose size is specified with clSetKernelArg. If the local memory size, for any pointer argument to the kernel declared with the __local address qualifier, is not specified, its size is assumed to be 0. |
CL_KERNEL_PREFERRED_WORK_GROUP_SIZE_MULTIPLE
|
size_t | Returns the preferred multiple of workgroup size for launch. This is a performance hint. Specifying a workgroup size that is not a multiple of the value returned by this query as the value of the local work size argument to clEnqueueNDRangeKernelwill not fail to enqueue the kernel for execution unless the work-group size specified is larger than the device maximum. |
CL_KERNEL_PRIVATE_MEM_SIZE
|
cl_ulong | Returns the minimum amount of private memory, in bytes, used by each workitem in the kernel. This value may include any private memory needed by an implementation to execute the kernel, including that used by the language built-ins and variable declared inside the kernel with the __private qualifier. |
param_value_size_ret
Returns the actual size in bytes of data copied to param_value
. If param_value_size_ret
is NULL, it is ignored.
Returns CL_SUCCESS if the function is executed successfully. Otherwise, it returns one of the following errors:
device
is not in the list of devices
associated with kernel
or if device
is NULL but there is more than
one device associated with kernel
.
param_name
is not valid, or if size in
bytes specified by param_value_size
is less than the size of return type as described in
the table above and param_value
is not NULL.
kernel
is a not a valid kernel object.
clCreateKernel, clCreateKernelsInProgram, clReleaseKernel, clRetainKernel, clSetKernelArg, clGetKernelInfo