通过BT Buffer实现高效的bias计算
【优先级】高
【描述】算子中进行带bias的矩阵乘计算时,可将bias数据搬运至C2(Bias Table Buffer)上,调用一次Mmad接口实现矩阵乘加bias的计算,或者直接调用Matmul高阶API完成功能。相比于先将矩阵乘的结果从CO1(L0C)搬运到GM上,再搬运到UB上进行加bias的过程,减少了数据搬运的次数,可提升内存使用效率。数据流图对比如下:
图1 反例数据流图


图2 正例数据流图


【反例】
该算子进行带bias的矩阵乘计算时,过程如下:
- 将矩阵乘的计算结果从CO1(L0C)搬运到workspace(GM)上;
- 从workspace搬运到UB上;
- 在UB上进行加bias的运算;
- 最后将结果搬运到GM。
当循环n次该计算过程,则分别增加了n次CO1->workspace、workspace->UB的搬运。
// 该样例仅做示例说明,非完整代码,省略了部分同步控制代码
public:
__aicore__ inline KernelSample()
{
aSize = m * k;
bSize = k * n;
cSize = m * n;
}
__aicore__ inline void Init(__gm__ uint8_t *a, __gm__ uint8_t *b, __gm__ uint8_t *bias, __gm__ uint8_t *c)
{
aGM.SetGlobalBuffer((__gm__ half *)a);
bGM.SetGlobalBuffer((__gm__ half *)b);
cGM.SetGlobalBuffer((__gm__ float *)c);
biasGM.SetGlobalBuffer((__gm__ float *)bias);
pipe.InitBuffer(inQueueA1, 1, aSize * sizeof(half));
pipe.InitBuffer(inQueueA2, 1, aSize * sizeof(half));
pipe.InitBuffer(inQueueB1, 1, bSize * sizeof(half));
pipe.InitBuffer(inQueueB2, 2, bSize * sizeof(half));
pipe.InitBuffer(outQueueCO1, 1, cSize * sizeof(float));
pipe.InitBuffer(inQueueBias, 1, n * sizeof(float));
pipe.InitBuffer(inQueueSrc0, 1, cSize * sizeof(float));
pipe.InitBuffer(outQueueDst, 1, cSize * sizeof(float));
}
__aicore__ inline void Process()
{
CopyIn();
SplitA();
SplitB();
Compute();
CopyOut();
CopyIn1();
Compute1();
CopyOut1();
}
private:
__aicore__ inline void CopyIn()
{
LocalTensor<half> a1Local = inQueueA1.AllocTensor<half>();
LocalTensor<half> b1Local = inQueueB1.AllocTensor<half>();
LocalTensor<float> biasLocal = inQueueBias.AllocTensor<float>();
Nd2NzParams dataCopyA1Params;
dataCopyA1Params.ndNum = 1;
dataCopyA1Params.nValue = m;
dataCopyA1Params.dValue = k;
dataCopyA1Params.srcNdMatrixStride = 0;
dataCopyA1Params.srcDValue = k;
dataCopyA1Params.dstNzC0Stride = m;
dataCopyA1Params.dstNzNStride = 1;
dataCopyA1Params.dstNzMatrixStride = 0;
DataCopy(a1Local, aGM, dataCopyA1Params);
Nd2NzParams dataCopyB1Params;
dataCopyB1Params.ndNum = 1;
dataCopyB1Params.nValue = k;
dataCopyB1Params.dValue = n;
dataCopyB1Params.srcNdMatrixStride = 0;
dataCopyB1Params.srcDValue = n;
dataCopyB1Params.dstNzC0Stride = k;
dataCopyB1Params.dstNzNStride = 1;
dataCopyB1Params.dstNzMatrixStride = 0;
DataCopy(b1Local, bGM, dataCopyB1Params);
// 将bias搬运到UB
DataCopy(biasLocal, biasGM, n);
inQueueA1.EnQue(a1Local);
inQueueB1.EnQue(b1Local);
inQueueBias.EnQue(biasLocal);
}
__aicore__ inline void SplitA()
{
...
}
__aicore__ inline void SplitB()
{
...
}
__aicore__ inline void Compute()
{
LocalTensor<half> a2Local = inQueueA2.DeQue<half>();
LocalTensor<half> b2Local = inQueueB2.DeQue<half>();
LocalTensor<float> c1Local = outQueueCO1.AllocTensor<float>();
MmadParams mmadParams;
mmadParams.m = m;
mmadParams.n = n;
mmadParams.k = k;
// 矩阵乘
Mmad(c1Local, a2Local, b2Local, mmadParams); // m*n
outQueueCO1.EnQue<float>(c1Local);
inQueueA2.FreeTensor(a2Local);
inQueueB2.FreeTensor(b2Local);
}
__aicore__ inline void CopyOut()
{
LocalTensor<float> c1Local = outQueueCO1.DeQue<float>();
GM_ADDR usrWorkspace = AscendC::GetUserWorkspace(workspace);
xGm.SetGlobalBuffer((__gm__ float *)(usrWorkspace));
FixpipeParamsV220 fixpipeParams;
fixpipeParams.nSize = n;
fixpipeParams.mSize = m;
fixpipeParams.srcStride = m;
fixpipeParams.dstStride = n;
fixpipeParams.ndNum = 1;
fixpipeParams.srcNdStride = 0;
fixpipeParams.dstNdStride = 0;
// 将矩阵乘的计算结果从CO1搬运到workspace
Fixpipe(xGm, c1Local, fixpipeParams);
outQueueCO1.FreeTensor(c1Local);
}
__aicore__ inline void CopyIn1()
{
PipeBarrier<PIPE_ALL>();
// 将矩阵乘的计算结果从workspace搬运到UB
LocalTensor<float> src0Local = inQueueSrc0.AllocTensor<float>();
DataCopy(src0Local, xGm, cSize);
inQueueSrc0.EnQue(src0Local);
}
__aicore__ inline void Compute1()
{
LocalTensor<float> src0Local = inQueueSrc0.DeQue<float>();
LocalTensor<float> biasLocal = inQueueBias.DeQue<float>();
LocalTensor<float> dstLocal = outQueueDst.AllocTensor<float>();
BinaryRepeatParams addRepeatParams;
addRepeatParams.dstRepStride = 8;
addRepeatParams.src0RepStride = 8;
addRepeatParams.src1RepStride = 0;
// 加bias的运算
Add(dstLocal, src0Local, biasLocal, 32, m, addRepeatParams);
outQueueDst.EnQue<float>(dstLocal);
inQueueSrc0.FreeTensor(src0Local);
inQueueBias.FreeTensor(biasLocal);
}
__aicore__ inline void CopyOut1()
{
...
}
private:
TPipe pipe;
TQue<TPosition::A1, 1> inQueueA1;
TQue<TPosition::A2, 1> inQueueA2;
TQue<TPosition::B1, 1> inQueueB1;
TQue<TPosition::B2, 1> inQueueB2;
TQue<TPosition::VECIN, 1> inQueueBias;
TQue<TPosition::VECIN, 1> inQueueSrc0;
TQue<TPosition::VECOUT, 1> outQueueDst;
GlobalTensor<half> aGM;
GlobalTensor<half> bGM;
GlobalTensor<float> cGM;
GlobalTensor<float> biasGM;
uint16_t m = 32, k = 32, n = 32;
uint16_t aSize, bSize, cSize;
...
【正例】
该算子进行带bias的矩阵乘计算时,先将bias搬运到BT上,调用一次Mmad接口实现矩阵乘加bias的计算。
...
// 该样例仅做示例说明,非完整代码,省略了部分同步控制代码
public:
__aicore__ inline KernelSample()
{
aSize = m * k;
bSize = k * n;
cSize = m * n;
}
__aicore__ inline void Init(__gm__ uint8_t *a, __gm__ uint8_t *b, __gm__ uint8_t *bias, __gm__ uint8_t *c)
{
aGM.SetGlobalBuffer((__gm__ half *)a);
bGM.SetGlobalBuffer((__gm__ half *)b);
cGM.SetGlobalBuffer((__gm__ float *)c);
biasGM.SetGlobalBuffer((__gm__ float *)bias);
pipe.InitBuffer(inQueueA1, 1, aSize * sizeof(half));
pipe.InitBuffer(inQueueA2, 1, aSize * sizeof(half));
pipe.InitBuffer(inQueueB1, 1, bSize * sizeof(half));
pipe.InitBuffer(inQueueB2, 2, bSize * sizeof(half));
pipe.InitBuffer(outQueueCO1, 1, cSize * sizeof(float));
pipe.InitBuffer(inQueueC1, 1, n * sizeof(float));
pipe.InitBuffer(outQueueC2, 1, n * sizeof(float));
}
__aicore__ inline void Process()
{
CopyIn();
SplitA();
SplitB();
SplitBias();
Compute();
CopyOut();
}
private:
__aicore__ inline void CopyIn()
{
LocalTensor<half> a1Local = inQueueA1.AllocTensor<half>();
LocalTensor<half> b1Local = inQueueB1.AllocTensor<half>();
LocalTensor<float> bias1Local = inQueueC1.AllocTensor<float>();
Nd2NzParams dataCopyA1Params;
dataCopyA1Params.ndNum = 1;
dataCopyA1Params.nValue = m;
dataCopyA1Params.dValue = k;
dataCopyA1Params.srcNdMatrixStride = 0;
dataCopyA1Params.srcDValue = k;
dataCopyA1Params.dstNzC0Stride = m;
dataCopyA1Params.dstNzNStride = 1;
dataCopyA1Params.dstNzMatrixStride = 0;
DataCopy(a1Local, aGM, dataCopyA1Params);
Nd2NzParams dataCopyB1Params;
dataCopyB1Params.ndNum = 1;
dataCopyB1Params.nValue = k;
dataCopyB1Params.dValue = n;
dataCopyB1Params.srcNdMatrixStride = 0;
dataCopyB1Params.srcDValue = n;
dataCopyB1Params.dstNzC0Stride = k;
dataCopyB1Params.dstNzNStride = 1;
dataCopyB1Params.dstNzMatrixStride = 0;
DataCopy(b1Local, bGM, dataCopyB1Params);
// 将bias从GM搬运到L1
DataCopy(bias1Local, biasGM, n);
inQueueA1.EnQue(a1Local);
inQueueB1.EnQue(b1Local);
inQueueC1.EnQue(bias1Local);
}
__aicore__ inline void SplitA()
{
...
}
__aicore__ inline void SplitB()
{
...
}
__aicore__ inline void SplitBias()
{
LocalTensor<float> bias1Local = inQueueC1.DeQue<float>();
LocalTensor<float> bias2Local = outQueueC2.AllocTensor<float>();
// 将bias从L1搬运到BT
DataCopy(bias2Local, bias1Local, { 1, (uint16_t)(n * sizeof(float) / 64), 0, 0 });
outQueueC2.EnQue<float>(bias2Local);
inQueueC1.FreeTensor(bias1Local);
}
__aicore__ inline void Compute()
{
LocalTensor<half> a2Local = inQueueA2.DeQue<half>();
LocalTensor<half> b2Local = inQueueB2.DeQue<half>();
LocalTensor<float> bias2Local = outQueueC2.DeQue<float>();
LocalTensor<float> c1Local = outQueueCO1.AllocTensor<float>();
MmadParams mmadParams;
mmadParams.m = m;
mmadParams.n = n;
mmadParams.k = k;
mmadParams.cmatrixInitVal = false;
// 矩阵乘
Mmad(c1Local, a2Local, b2Local, bias2Local, mmadParams);
outQueueCO1.EnQue<float>(c1Local);
inQueueA2.FreeTensor(a2Local);
inQueueB2.FreeTensor(b2Local);
outQueueC2.FreeTensor(bias2Local);
}
__aicore__ inline void CopyOut()
{
LocalTensor<float> c1Local = outQueueCO1.DeQue<float>();
FixpipeParamsV220 fixpipeParams;
fixpipeParams.nSize = n;
fixpipeParams.mSize = m;
fixpipeParams.srcStride = m;
fixpipeParams.dstStride = n;
fixpipeParams.ndNum = 1;
fixpipeParams.srcNdStride = 0;
fixpipeParams.dstNdStride = 0;
Fixpipe(cGM, c1Local, fixpipeParams);
outQueueCO1.FreeTensor(c1Local);
}
private:
TPipe pipe;
TQue<TPosition::A1, 1> inQueueA1;
TQue<TPosition::A2, 1> inQueueA2;
TQue<TPosition::B1, 1> inQueueB1;
TQue<TPosition::B2, 1> inQueueB2;
TQue<TPosition::CO1, 1> outQueueCO1;
TQue<TPosition::C1, 1> inQueueC1;
TQue<TPosition::C2, 1> outQueueC2;
GlobalTensor<half> aGM;
GlobalTensor<half> bGM;
GlobalTensor<float> cGM;
GlobalTensor<float> biasGM;
uint16_t m = 32, k = 32, n = 32;
uint16_t aSize, bSize, cSize;
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