InitStartBufHandle

Product Support

Product	Supported
Atlas A3 training products/Atlas A3 inference products	√
Atlas A2 training products/Atlas A2 inference products	√
Atlas 200I/500 A2 inference products	√
Atlas inference product's AI Core	√
Atlas inference product's Vector Core	x
Atlas training products	√

Function

Sets the start buffer pointer, number of buffers, and size of each buffer of TQue/TBuf.

Prototype

__aicore__ inline void InitStartBufHandle(TBufHandle startBufhandle, uint8_t num, uint32_t len)

Parameters

**Table 1** Parameters
Parameter	Input/Output	Meaning
startBufhandle	Input	Pointer to the start buffer of TQue/TBuf. The data type is TBufHandle (actually uint8_t*).
num	Input	Number of allocated buffers.
len	Input	Size of each buffer. The unit is byte.

Restrictions

The TQue and TBuf classes are inherited from the TQueBind class. Therefore, the TQue and TBuf objects can also use this API.

Currently, this API is provided only for Customized TBufPool to initialize the buffers of TQue and TBuf.
When the TBuf object is used to call this API, the value of the passed-in parameter num must be 1.

Returns

None

Example

For details about the complete example, see Example.

// Assume that the custom TBufPool class is MyBufPool.
// InitBuffer for initializing the TQue in the custom TBufPool class:
template<class T> 
__aicore__ inline bool MyBufPool::InitBuffer(T& que, uint8_t num, uint32_t len)
{
   ...
   // Initialize the buffer of TQue.
   uint32_t curPoolAddr  = 0;  // Start address of the buffer.
   auto bufhandle = xxx; // Specific buffer. This variable can be obtained from the custom TBufPool.
   srcQue0.InitStartBufHandle(bufhandle, num, len);
   for (uint8_t i = 0; i < num; i++) {
      que.InitBufHandle(this, i, bufhandle , curPoolAddr + i * len, len);
   }
   ...
}

// InitBuffer for initializing the TBuf in the custom TBufPool class:
template<class T> 
__aicore__ inline bool MyBufPool::InitBuffer(AscendC::TBuf<bufPos>& buf, uint32_t len)
{
   ...
   // Initialize the buffer of TBuf.
   uint32_t curPoolAddr  = 0;  // Start address of the buffer.
   auto bufhandle = xxx; // Specific buffer. This variable can be obtained from the custom TBufPool.
   srcBuf1.InitStartBufHandle(bufhandle, 1, len);
   srcBuf1.InitBufHandle(this, 0, bufhandle , curPoolAddr, len);
   ...
}
AscendC::TPipe pipe;
AscendC::TQue<AscendC::TPosition::VECIN, 1> srcQue0;
AscendC::TBuf<AscendC::TPosition::VECIN> srcBuf1;
MyBufPool tbufPool;
pipe.InitBufPool(tbufPool, 1024 * 2);
tbufPool.InitBuffer(srcQue0, 1, 1024);
tbufPool.InitBuffer(srcBuf1, 1024);

Parent topic: TQueBind