[NVIDA] [1/N] Nvfp4 Masked Gemm: Add quant op for the flashinfer grouped gemm (#9200)
This commit is contained in:
@@ -157,6 +157,12 @@ TORCH_LIBRARY_FRAGMENT(sgl_kernel, m) {
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"Tensor output_scale_offset_by_experts) -> ()");
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m.impl("scaled_fp4_experts_quant", torch::kCUDA, &scaled_fp4_experts_quant);
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m.def(
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"silu_and_mul_scaled_fp4_experts_quant(Tensor! output, Tensor! output_scale,"
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"Tensor input, Tensor input_global_scale, Tensor input_offset_by_experts,"
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"Tensor output_scale_offset_by_experts, Tensor mask) -> ()");
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m.impl("silu_and_mul_scaled_fp4_experts_quant", torch::kCUDA, &silu_and_mul_scaled_fp4_experts_quant);
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m.def(
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"cutlass_fp4_group_mm(Tensor! output, Tensor a, Tensor b,"
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"Tensor a_blockscale, Tensor b_blockscale, Tensor alphas,"
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@@ -239,6 +239,33 @@ __device__ uint32_t cvt_warp_fp16_to_fp4(PackedVec<Type>& vec, float SFScaleVal,
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#endif
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}
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__device__ __forceinline__ float silu(const float& val) {
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return val / (1.0f + __expf(-val));
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}
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template <class Type>
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inline __device__ void silu_and_mul(PackedVec<Type>& x_vec, const PackedVec<Type>& y_vec) {
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float2 x[CVT_FP4_ELTS_PER_THREAD / 2];
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float2 y[CVT_FP4_ELTS_PER_THREAD / 2];
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#pragma unroll
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for (int i = 0; i < CVT_FP4_ELTS_PER_THREAD / 2; i++) {
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if constexpr (std::is_same_v<Type, half>) {
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x[i] = __half22float2(x_vec.elts[i]);
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y[i] = __half22float2(y_vec.elts[i]);
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x[i].x = silu(x[i].x) * y[i].x;
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x[i].y = silu(x[i].y) * y[i].y;
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x_vec.elts[i] = __float22half2_rn(x[i]);
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} else {
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x[i] = __bfloat1622float2(x_vec.elts[i]);
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y[i] = __bfloat1622float2(y_vec.elts[i]);
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x[i].x = silu(x[i].x) * y[i].x;
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x[i].y = silu(x[i].y) * y[i].y;
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x_vec.elts[i] = __float22bfloat162_rn(x[i]);
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}
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}
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}
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// Use UE4M3 by default.
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template <class Type, bool UE8M0_SF = false, bool SMALL_NUM_EXPERTS = false>
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__global__ void
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@@ -255,6 +282,7 @@ cvt_fp16_to_fp4(
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uint32_t* SFout,
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uint32_t* input_offset_by_experts,
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uint32_t* output_scale_offset_by_experts,
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int32_t* mask,
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int n_experts,
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bool low_latency) {
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#if defined(__CUDA_ARCH__) && (__CUDA_ARCH__ >= 1000)
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@@ -265,6 +293,11 @@ cvt_fp16_to_fp4(
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// Input tensor row/col loops.
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int tid = blockIdx.x * blockDim.x + threadIdx.x;
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int colsPerRow = numCols / CVT_FP4_ELTS_PER_THREAD;
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// TODO(kaixih@nvidia): For now, we assume mask is used together with
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// silu_and_mal. Maybe we want a more general behavior of mask later. In the
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// silu case, the input last dim doubles.
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bool use_mask = mask != nullptr;
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int actualColsPerRow = use_mask ? colsPerRow * 2 : colsPerRow;
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// Each global thread processes one element
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for (int globalIdx = tid; globalIdx < numRows * colsPerRow; globalIdx += gridDim.x * blockDim.x) {
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@@ -272,13 +305,6 @@ cvt_fp16_to_fp4(
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int rowIdx = globalIdx / colsPerRow;
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int colIdx = globalIdx % colsPerRow;
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int64_t inOffset = rowIdx * colsPerRow + colIdx;
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PackedVec in_vec = reinterpret_cast<PackedVec const*>(in)[inOffset];
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// Get the output tensor offset.
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// Same as inOffset because 8 elements are packed into one uint32_t.
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int64_t outOffset = inOffset;
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auto& out_pos = out[outOffset];
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// Find index within the experts using different strategies based on expert
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// count
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int rowIdx_in_expert = 0;
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@@ -321,6 +347,23 @@ cvt_fp16_to_fp4(
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}
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}
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// Eerly exit when using masks.
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if (use_mask && rowIdx_in_expert >= mask[expert_idx]) {
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continue;
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}
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int64_t inOffset = rowIdx * actualColsPerRow + colIdx;
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PackedVec in_vec = reinterpret_cast<PackedVec const*>(in)[inOffset];
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if (use_mask) {
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PackedVec in_vec_mul = reinterpret_cast<PackedVec const*>(in)[inOffset + colsPerRow];
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silu_and_mul(in_vec, in_vec_mul);
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}
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// Get the output tensor offset.
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// Same as inOffset because 8 elements are packed into one uint32_t.
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int64_t outOffset = rowIdx * colsPerRow + colIdx;
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auto& out_pos = out[outOffset];
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// Get the global scaling factor, which will be applied to the SF.
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// Note SFScale is the same as next GEMM's alpha, which is
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// (448.f / (Alpha_A / 6.f)).
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@@ -356,6 +399,7 @@ cvt_fp16_to_fp4(
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uint32_t* SFout,
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uint32_t* input_offset_by_experts,
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uint32_t* output_scale_offset_by_experts,
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int32_t* mask,
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int n_experts) {
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#if defined(__CUDA_ARCH__) && (__CUDA_ARCH__ >= 1000)
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using PackedVec = PackedVec<Type>;
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@@ -383,6 +427,8 @@ cvt_fp16_to_fp4(
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int tid = blockIdx.x * blockDim.x + threadIdx.x;
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int colsPerRow = numCols / CVT_FP4_ELTS_PER_THREAD;
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bool use_mask = mask != nullptr;
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int actualColsPerRow = use_mask ? colsPerRow * 2 : colsPerRow;
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// Each global thread processes one element
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for (int globalIdx = tid; globalIdx < numRows * colsPerRow; globalIdx += gridDim.x * blockDim.x) {
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@@ -390,11 +436,6 @@ cvt_fp16_to_fp4(
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int rowIdx = globalIdx / colsPerRow;
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int colIdx = globalIdx % colsPerRow;
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int64_t inOffset = rowIdx * colsPerRow + colIdx;
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PackedVec in_vec = reinterpret_cast<PackedVec const*>(in)[inOffset];
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int64_t outOffset = inOffset;
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auto& out_pos = out[outOffset];
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// Find expert using binary search for better performance with large m_topk
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int rowIdx_in_expert = 0;
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int expert_idx = 0;
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@@ -419,6 +460,21 @@ cvt_fp16_to_fp4(
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}
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}
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if (use_mask && rowIdx_in_expert >= mask[expert_idx]) {
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continue;
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}
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int64_t inOffset = rowIdx * actualColsPerRow + colIdx;
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PackedVec in_vec = reinterpret_cast<PackedVec const*>(in)[inOffset];
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if (use_mask) {
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PackedVec in_vec_mul = reinterpret_cast<PackedVec const*>(in)[inOffset + colsPerRow];
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silu_and_mul(in_vec, in_vec_mul);
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}
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int64_t outOffset = rowIdx * colsPerRow + colIdx;
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auto& out_pos = out[outOffset];
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float const SFScaleVal = SFScale == nullptr ? 1.0f : SFScale[expert_idx];
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int factor = CVT_FP4_SF_VEC_SIZE * 4;
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@@ -442,6 +498,7 @@ void quant_impl(
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void* input_global_scale,
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void* input_offset_by_experts,
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void* output_scale_offset_by_experts,
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void* mask,
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int m_topk,
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int k,
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int n_experts,
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@@ -478,6 +535,7 @@ void quant_impl(
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reinterpret_cast<uint32_t*>(output_scale),
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reinterpret_cast<uint32_t*>(input_offset_by_experts),
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reinterpret_cast<uint32_t*>(output_scale_offset_by_experts),
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reinterpret_cast<int32_t*>(mask),
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n_experts);
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} else {
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cvt_fp16_to_fp4<T, false, true><<<grid, block, shared_mem_size, stream>>>(
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@@ -489,6 +547,7 @@ void quant_impl(
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reinterpret_cast<uint32_t*>(output_scale),
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reinterpret_cast<uint32_t*>(input_offset_by_experts),
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reinterpret_cast<uint32_t*>(output_scale_offset_by_experts),
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reinterpret_cast<int32_t*>(mask),
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n_experts);
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}
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} else {
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@@ -502,6 +561,7 @@ void quant_impl(
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reinterpret_cast<uint32_t*>(output_scale),
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reinterpret_cast<uint32_t*>(input_offset_by_experts),
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reinterpret_cast<uint32_t*>(output_scale_offset_by_experts),
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reinterpret_cast<int32_t*>(mask),
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n_experts,
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/* bool low_latency */ true);
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} else {
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@@ -514,6 +574,7 @@ void quant_impl(
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reinterpret_cast<uint32_t*>(output_scale),
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reinterpret_cast<uint32_t*>(input_offset_by_experts),
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reinterpret_cast<uint32_t*>(output_scale_offset_by_experts),
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reinterpret_cast<int32_t*>(mask),
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n_experts,
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/* bool low_latency */ true);
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}
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@@ -590,6 +651,7 @@ void scaled_fp4_experts_quant_sm100a(
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input_global_scale.data_ptr(),
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input_offset_by_experts.data_ptr(),
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output_scale_offset_by_experts.data_ptr(),
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nullptr, // mask
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m_topk,
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k,
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n_experts,
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@@ -602,6 +664,92 @@ void scaled_fp4_experts_quant_sm100a(
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input_global_scale.data_ptr(),
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input_offset_by_experts.data_ptr(),
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output_scale_offset_by_experts.data_ptr(),
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nullptr, // mask
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m_topk,
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k,
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n_experts,
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stream);
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} else {
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TORCH_CHECK(false, "Expected input data type to be half or bfloat16");
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}
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}
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void silu_and_mul_scaled_fp4_experts_quant_sm100a(
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torch::Tensor& output,
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torch::Tensor& output_scale,
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torch::Tensor const& input,
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torch::Tensor const& input_global_scale,
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torch::Tensor const& input_offset_by_experts,
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torch::Tensor const& output_scale_offset_by_experts,
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torch::Tensor const& mask) {
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CHECK_INPUT(output, "output must be a CUDA tensor");
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CHECK_INPUT(output_scale, "output_scale must be a CUDA tensor");
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CHECK_INPUT(input, "input must be a CUDA tensor");
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CHECK_INPUT(input_global_scale, "input_global_scale must be a CUDA tensor");
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CHECK_INPUT(input_offset_by_experts, "input_offset_by_experts must be a CUDA tensor");
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CHECK_INPUT(output_scale_offset_by_experts, "output_scale_offset_by_experts must be a CUDA tensor");
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CHECK_INPUT(mask, "mask must be a CUDA tensor");
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TORCH_CHECK(output.dim() == 2);
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TORCH_CHECK(output_scale.dim() == 2);
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TORCH_CHECK(input.dim() == 2);
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TORCH_CHECK(input_global_scale.dim() == 1);
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TORCH_CHECK(input_offset_by_experts.dim() == 1);
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TORCH_CHECK(output_scale_offset_by_experts.dim() == 1);
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TORCH_CHECK(input.scalar_type() == HALF || input.scalar_type() == BF16);
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TORCH_CHECK(input_global_scale.scalar_type() == FLOAT);
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TORCH_CHECK(input_offset_by_experts.scalar_type() == INT);
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TORCH_CHECK(output_scale_offset_by_experts.scalar_type() == INT);
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TORCH_CHECK(mask.scalar_type() == INT);
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// output is uint8 (two nvfp4 values are packed into one uint8)
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// output_scale is int32 (four fp8 values are packed into one int32)
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TORCH_CHECK(output.scalar_type() == UINT8);
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TORCH_CHECK(output_scale.scalar_type() == INT);
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const int BLOCK_SIZE = 16;
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auto m_topk = input.size(0);
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auto k_by_2 = input.size(1);
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TORCH_CHECK(k_by_2 % 2 == 0, "k must be a multiple of 2");
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auto k = k_by_2 / 2;
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TORCH_CHECK(k % BLOCK_SIZE == 0, "k must be a multiple of 16");
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auto n_experts = input_global_scale.size(0);
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TORCH_CHECK(input_offset_by_experts.size(0) == n_experts + 1);
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TORCH_CHECK(output_scale_offset_by_experts.size(0) == n_experts + 1);
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TORCH_CHECK(mask.size(0) == n_experts);
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TORCH_CHECK(output.size(0) == m_topk);
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TORCH_CHECK(output.size(1) == k / 2);
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int scales_k = k / BLOCK_SIZE;
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// 4 means the swizzle requirement by nvidia nvfp4.
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int padded_k = (scales_k + (4 - 1)) / 4 * 4;
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// 4 means 4 fp8 values are packed into one int32
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TORCH_CHECK(output_scale.size(1) * 4 == padded_k);
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auto in_dtype = input.dtype();
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at::cuda::CUDAGuard device_guard{(char)input.get_device()};
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const cudaStream_t stream = at::cuda::getCurrentCUDAStream(input.get_device());
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if (in_dtype == at::ScalarType::Half) {
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quant_impl<half>(
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output.data_ptr(),
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output_scale.data_ptr(),
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input.data_ptr(),
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input_global_scale.data_ptr(),
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input_offset_by_experts.data_ptr(),
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output_scale_offset_by_experts.data_ptr(),
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mask.data_ptr(),
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m_topk,
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k,
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n_experts,
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stream);
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} else if (in_dtype == at::ScalarType::BFloat16) {
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quant_impl<__nv_bfloat16>(
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output.data_ptr(),
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output_scale.data_ptr(),
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input.data_ptr(),
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input_global_scale.data_ptr(),
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input_offset_by_experts.data_ptr(),
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output_scale_offset_by_experts.data_ptr(),
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mask.data_ptr(),
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m_topk,
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k,
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n_experts,
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@@ -27,6 +27,15 @@ void scaled_fp4_experts_quant_sm100a(
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torch::Tensor const& input_offset_by_experts,
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torch::Tensor const& output_scale_offset_by_experts);
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void silu_and_mul_scaled_fp4_experts_quant_sm100a(
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torch::Tensor& output,
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torch::Tensor& output_scale,
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torch::Tensor const& input,
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torch::Tensor const& input_global_scale,
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torch::Tensor const& input_offset_by_experts,
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torch::Tensor const& output_scale_offset_by_experts,
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torch::Tensor const& mask);
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#endif
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void scaled_fp4_quant(
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@@ -50,3 +59,18 @@ void scaled_fp4_experts_quant(
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#endif
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TORCH_CHECK_NOT_IMPLEMENTED(false, "No compiled nvfp4 experts quantization kernel");
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}
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void silu_and_mul_scaled_fp4_experts_quant(
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torch::Tensor& output,
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torch::Tensor& output_scale,
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torch::Tensor const& input,
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torch::Tensor const& input_global_scale,
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torch::Tensor const& input_offset_by_experts,
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torch::Tensor const& output_scale_offset_by_experts,
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torch::Tensor const& mask) {
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#if defined ENABLE_NVFP4 && ENABLE_NVFP4
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return silu_and_mul_scaled_fp4_experts_quant_sm100a(
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output, output_scale, input, input_global_scale, input_offset_by_experts, output_scale_offset_by_experts, mask);
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#endif
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TORCH_CHECK_NOT_IMPLEMENTED(false, "No compiled nvfp4 experts quantization kernel");
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}
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@@ -389,6 +389,14 @@ void scaled_fp4_experts_quant(
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torch::Tensor const& input_offset_by_experts,
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torch::Tensor const& output_scale_offset_by_experts);
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void silu_and_mul_scaled_fp4_experts_quant(
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torch::Tensor& output,
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torch::Tensor& output_scale,
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torch::Tensor const& input,
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torch::Tensor const& input_global_scale,
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torch::Tensor const& input_offset_by_experts,
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torch::Tensor const& output_scale_offset_by_experts,
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torch::Tensor const& mask);
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/*
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* From csrc/moe/cutlass_moe/w4a8
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*/
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@@ -52,12 +52,14 @@ from sgl_kernel.gemm import (
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qserve_w4a8_per_chn_gemm,
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qserve_w4a8_per_group_gemm,
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scaled_fp4_experts_quant,
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scaled_fp4_grouped_quant,
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scaled_fp4_quant,
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sgl_per_tensor_quant_fp8,
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sgl_per_token_group_quant_fp8,
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sgl_per_token_group_quant_int8,
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sgl_per_token_quant_fp8,
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shuffle_rows,
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silu_and_mul_scaled_fp4_grouped_quant,
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)
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from sgl_kernel.grammar import apply_token_bitmask_inplace_cuda
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from sgl_kernel.kvcacheio import (
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@@ -295,6 +295,142 @@ def shuffle_rows(input_tensor, dst2src_map, output_tensor_shape):
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return output_tensor
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def scaled_fp4_grouped_quant(
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input_tensor: torch.Tensor,
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input_global_scale: torch.Tensor,
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):
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"""
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Quantize input tensor to FP4 and return quantized tensor and scale, for
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grouped gemm inputs (e.g., grouped_gemm_nt_masked for flashinfer).
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Args:
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input: The input tensor to be quantized to FP4, with shape (l, m, k)
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l is number of groups, m is number of tokens per group, k is number of features.
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input_global_scale: A scalar scaling factor for the entire tensor, with
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shape (l,).
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Outputs:
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output: The quantized tensor in FP4, with shape (m, k // 2, l) but the physical
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layout is (l, m, k // 2). `// 2` is because two fp4 values are packed into
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an uint8.
|
||||
output_scales: The blockscale tensor in FP8-E4M3, with shape (32, 4, rm, 4, rk, l)
|
||||
but the physical layout is (l, rm, rk, 32, 4, 4).
|
||||
Note:
|
||||
For the shape of output_scales, `32 * 4 * rm` is a padded m to nearest multiple of 128.
|
||||
`4 * rk` is a padded `k // 16` to nearest multiple of 4. These layout constants are
|
||||
required by the NVIDIA Blackwell MMA operations.
|
||||
"""
|
||||
device = input_tensor.device
|
||||
l, m, k = input_tensor.shape
|
||||
sf_vec_size = 16
|
||||
assert k % sf_vec_size == 0, f"k must be multiple of 16, but got {k}."
|
||||
|
||||
scale_k = k // sf_vec_size
|
||||
padded_k = (scale_k + (4 - 1)) // 4 * 4
|
||||
padded_k_int32 = padded_k // 4
|
||||
padded_m = (m + (128 - 1)) // 128 * 128
|
||||
output = torch.empty(l, m, k // 2, device=device, dtype=torch.uint8)
|
||||
output_scales = torch.empty(
|
||||
l, padded_m, padded_k_int32, device=device, dtype=torch.int32
|
||||
)
|
||||
input_offsets = torch.arange(0, (l + 1) * m, step=m, dtype=torch.int, device=device)
|
||||
output_offsets = torch.arange(
|
||||
0,
|
||||
(l + 1) * padded_m,
|
||||
step=padded_m,
|
||||
dtype=torch.int,
|
||||
device=device,
|
||||
)
|
||||
|
||||
torch.ops.sgl_kernel.scaled_fp4_experts_quant.default(
|
||||
output.view(l * m, k // 2),
|
||||
output_scales.view(l * padded_m, padded_k_int32),
|
||||
input_tensor.view(l * m, k),
|
||||
input_global_scale,
|
||||
input_offsets,
|
||||
output_offsets,
|
||||
)
|
||||
# The physical layout of the output is (l, m, k // 2), but we want to return a
|
||||
# logical layout (m, k // 2, l) required by the flashinfer masked group gemm.
|
||||
output = output.permute(1, 2, 0)
|
||||
# The physical layout of the output scales is already swizzled as (l, rm, rk, 32, 4, 4), a
|
||||
# requirement for the flashinfer masked group gemm, where rm=m/128 and rk=k/4. The logic
|
||||
# layout is (32, 4, rm, 4, rk, l).
|
||||
output_scales = output_scales.view(torch.float8_e4m3fn).view(
|
||||
l, padded_m // 128, padded_k // 4, 32, 4, 4
|
||||
)
|
||||
output_scales = output_scales.permute(3, 4, 1, 5, 2, 0)
|
||||
return output, output_scales
|
||||
|
||||
|
||||
def silu_and_mul_scaled_fp4_grouped_quant(
|
||||
input_tensor: torch.Tensor,
|
||||
input_global_scale: torch.Tensor,
|
||||
mask: torch.Tensor,
|
||||
):
|
||||
"""
|
||||
Quantize input tensor to FP4 and return quantized tensor and scale, for
|
||||
grouped gemm inputs (e.g., grouped_gemm_nt_masked for flashinfer).
|
||||
Args:
|
||||
input: The input tensor to be quantized to FP4, with shape (l, m, k * 2)
|
||||
l is number of groups, m is number of tokens per group, k is number of features.
|
||||
input_global_scale: A scalar scaling factor for the entire tensor, with
|
||||
shape (l,).
|
||||
mask: The mask tensor, with shape (l,)
|
||||
Outputs:
|
||||
output: The quantized tensor in FP4, with shape (m, k // 2, l) but the physical
|
||||
layout is (l, m, k // 2). `// 2` is because two fp4 values are packed into
|
||||
an uint8.
|
||||
output_scales: The blockscale tensor in FP8-E4M3, with shape (32, 4, rm, 4, rk, l)
|
||||
but the physical layout is (l, rm, rk, 32, 4, 4).
|
||||
Note:
|
||||
For the shape of output_scales, `32 * 4 * rm` is a padded m to nearest multiple of 128.
|
||||
`4 * rk` is a padded `k // 16` to nearest multiple of 4. These layout constants are
|
||||
required by the NVIDIA Blackwell MMA operations.
|
||||
"""
|
||||
device = input_tensor.device
|
||||
l, m, k_by_2 = input_tensor.shape
|
||||
k = k_by_2 // 2
|
||||
sf_vec_size = 16
|
||||
assert k % sf_vec_size == 0, f"k must be multiple of 16, but got {k}."
|
||||
|
||||
scale_k = k // sf_vec_size
|
||||
padded_k = (scale_k + (4 - 1)) // 4 * 4
|
||||
padded_k_int32 = padded_k // 4
|
||||
padded_m = (m + (128 - 1)) // 128 * 128
|
||||
output = torch.empty(l, m, k // 2, device=device, dtype=torch.uint8)
|
||||
output_scales = torch.empty(
|
||||
l, padded_m, padded_k_int32, device=device, dtype=torch.int32
|
||||
)
|
||||
input_offsets = torch.arange(0, (l + 1) * m, step=m, dtype=torch.int, device=device)
|
||||
output_offsets = torch.arange(
|
||||
0,
|
||||
(l + 1) * padded_m,
|
||||
step=padded_m,
|
||||
dtype=torch.int,
|
||||
device=device,
|
||||
)
|
||||
|
||||
torch.ops.sgl_kernel.silu_and_mul_scaled_fp4_experts_quant.default(
|
||||
output.view(l * m, k // 2),
|
||||
output_scales.view(l * padded_m, padded_k_int32),
|
||||
input_tensor.view(l * m, k_by_2),
|
||||
input_global_scale,
|
||||
input_offsets,
|
||||
output_offsets,
|
||||
mask,
|
||||
)
|
||||
# The physical layout of the output is (l, m, k // 2), but we want to return a
|
||||
# logical layout (m, k // 2, l) required by the flashinfer masked group gemm.
|
||||
output = output.permute(1, 2, 0)
|
||||
# The physical layout of the output scales is already swizzled as (l, rm, rk, 32, 4, 4), a
|
||||
# requirement for the flashinfer masked group gemm, where rm=m/128 and rk=k/4. The logic
|
||||
# layout is (32, 4, rm, 4, rk, l).
|
||||
output_scales = output_scales.view(torch.float8_e4m3fn).view(
|
||||
l, padded_m // 128, padded_k // 4, 32, 4, 4
|
||||
)
|
||||
output_scales = output_scales.permute(3, 4, 1, 5, 2, 0)
|
||||
return output, output_scales
|
||||
|
||||
|
||||
def scaled_fp4_experts_quant(
|
||||
input_tensor: torch.Tensor,
|
||||
input_global_scale: torch.Tensor,
|
||||
|
||||
@@ -1,6 +1,11 @@
|
||||
import pytest
|
||||
import torch
|
||||
from sgl_kernel import scaled_fp4_quant
|
||||
from sgl_kernel import (
|
||||
scaled_fp4_grouped_quant,
|
||||
scaled_fp4_quant,
|
||||
silu_and_mul,
|
||||
silu_and_mul_scaled_fp4_grouped_quant,
|
||||
)
|
||||
|
||||
skip_condition = torch.cuda.get_device_capability() < (10, 0)
|
||||
|
||||
@@ -166,5 +171,83 @@ def test_quantize_to_fp4_padded(pad_shape: tuple[int, int]) -> None:
|
||||
torch.testing.assert_close(scale_ans, scale_ref)
|
||||
|
||||
|
||||
@pytest.mark.skipif(
|
||||
skip_condition, reason="Nvfp4 Requires compute capability of 10 or above."
|
||||
)
|
||||
def test_quantize_to_fp4_grouped():
|
||||
torch.manual_seed(42)
|
||||
torch.set_default_device("cuda:0")
|
||||
|
||||
l, m, k = 2, 512, 2048
|
||||
x = torch.randn((l, m, k), dtype=torch.bfloat16)
|
||||
tensor_amax = x.abs().amax(dim=(1, 2)).to(torch.float32)
|
||||
x_sf_global = FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX / tensor_amax
|
||||
output, output_scales = scaled_fp4_grouped_quant(
|
||||
x,
|
||||
x_sf_global,
|
||||
)
|
||||
# output in logical (m, k, l), but its physical layout is (l, m, k).
|
||||
# So permute first to (l, m, k).
|
||||
output = output.permute(2, 0, 1)
|
||||
# output_scale in logical (32, 4, rm, 4, rk, l), but its physical layout is (l, rm, rk, 32, 4, 4).
|
||||
# So permute first to (l, rm, rk, 32, 4, 4).
|
||||
padded_m = ((m + 128 - 1) // 128) * 128
|
||||
output_scales = output_scales.permute(5, 2, 4, 0, 1, 3).view(l, padded_m, -1)
|
||||
for i in range(l):
|
||||
a_fp4, a_scale_interleaved = scaled_fp4_quant(x[i], x_sf_global[i])
|
||||
torch.testing.assert_close(a_fp4, output[i])
|
||||
torch.testing.assert_close(
|
||||
a_scale_interleaved.to(torch.float), output_scales[i].to(torch.float)
|
||||
)
|
||||
|
||||
|
||||
@pytest.mark.skipif(
|
||||
skip_condition, reason="Nvfp4 Requires compute capability of 10 or above."
|
||||
)
|
||||
@pytest.mark.parametrize("shape", [(32, 100, 2048), (32, 512, 2048)])
|
||||
def test_silu_and_mul_quantize_to_fp4_grouped(shape: tuple[int, int]) -> None:
|
||||
torch.manual_seed(42)
|
||||
torch.set_default_device("cuda:0")
|
||||
|
||||
l, m, k = shape
|
||||
x = torch.randn((l, m, k * 2), dtype=torch.bfloat16)
|
||||
max_m = 8
|
||||
assert max_m <= m
|
||||
mask = torch.randint(1, max_m, (l,), dtype=torch.int32)
|
||||
|
||||
ref_y = silu_and_mul(x)
|
||||
tensor_amax = ref_y.abs().amax(dim=(1, 2)).to(torch.float32)
|
||||
y_sf_global = FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX / tensor_amax
|
||||
ref_output, ref_output_scales = scaled_fp4_grouped_quant(
|
||||
ref_y,
|
||||
y_sf_global,
|
||||
)
|
||||
output, output_scales = silu_and_mul_scaled_fp4_grouped_quant(
|
||||
x,
|
||||
y_sf_global,
|
||||
mask,
|
||||
)
|
||||
|
||||
# output in logical (m, k, l), but its physical layout is (l, m, k).
|
||||
# So permute first to (l, m, k).
|
||||
output = output.permute(2, 0, 1)
|
||||
ref_output = ref_output.permute(2, 0, 1)
|
||||
|
||||
# output_scale in logical (32, 4, rm, 4, rk, l), but its physical layout is (l, rm, rk, 32, 4, 4).
|
||||
# So permute first to (l, rm, rk, 32, 4, 4).
|
||||
padded_m = ((m + 128 - 1) // 128) * 128
|
||||
output_scales = output_scales.permute(5, 2, 4, 0, 1, 3).view(l, padded_m, -1)
|
||||
ref_output_scales = ref_output_scales.permute(5, 2, 4, 0, 1, 3).view(
|
||||
l, padded_m, -1
|
||||
)
|
||||
|
||||
for i in range(l):
|
||||
torch.testing.assert_close(ref_output[i, : mask[i]], output[i, : mask[i]])
|
||||
# We need to recover the swizzled scales to linear layout before applying mask slice.
|
||||
scale_ref = recover_swizzled_scales(ref_output_scales[i], m, k)
|
||||
scale_ans = recover_swizzled_scales(output_scales[i], m, k)
|
||||
torch.testing.assert_close(scale_ref[: mask[i]], scale_ans[: mask[i]])
|
||||
|
||||
|
||||
if __name__ == "__main__":
|
||||
pytest.main([__file__])
|
||||
|
||||
Reference in New Issue
Block a user