FFTThread

Set the maximum number of threads:
HmppResult HMPP_SetFFTNumberThreads(int32_t fftNumberThreads);

Obtain the current number of threads:
HmppResult HMPP_GetFFTNumberThreads(int32_t* fftNumberThreads);

Parameters

Parameter	Description	Value Range	Input/Output
fftNumberThreads	Maximum number of threads (SetFFTNumberThreads).	Greater than 0.	Input
fftNumberThreads	Pointer to the number of threads (GetFFTNumberThreads).	The value cannot be NULL.	Output

Return Value

Success: HMPP_STS_NO_ERR
Failure: An error code is returned.

Error Codes

Error Code	Description
HMPP_STS_NULL_PTR_ERR	The input pointer is NULL.
HMPP_STS_SIZE_ERR	The value of len is less than or equal to 0.

Example

#define NUMBER_THREAD_FFT 4
void FFT_Thread_Example()
{
    int curNum = 0;
    HMPP_GetNumberThreads(&curNum);
    printf("curNum = %d\n", curNum);

    HMPP_SetFFTNumberThreads(NUMBER_THREAD_FFT);
    int num = 0;
    HMPP_GetNumberThreads(&num);
    printf("num = %d\n", num);
}

Output:

curNum = 8
num = 4

By default, the number of FFT threads in the HMPP is 8. You can use the HMPP_SetFFTNumberThreads function described in this section to set the number of FFT threads used for current task execution. The setting is not permanently valid.
In addition, you can set the number of FFT threads through the HUAWEI_HMPP_FFT_THREAD_NUM environment variable.

Parent topic: Basic Functions