sglang.0.4.8.post1/sglang/sgl-kernel/csrc/cpu/norm.cpp

305 lines
9.9 KiB
C++

#include "common.h"
#include "vec.h"
namespace {
// NB: avoid using `at::vec::map<>` on bfloat16 or half
// Llama4TextL2Norm
template <typename scalar_t>
void l2norm_kernel_impl(
scalar_t* __restrict__ output,
const scalar_t* __restrict__ input,
int64_t batch_size,
int64_t hidden_size,
float eps = 1e-5) {
using bVec = at::vec::Vectorized<scalar_t>;
using fVec = at::vec::Vectorized<float>;
constexpr int kVecSize = bVec::size();
at::parallel_for(0, batch_size, 0, [&](int64_t begin, int64_t end) {
for (int64_t i = begin; i < end; ++i) {
// local ptrs
scalar_t* __restrict__ out_ptr = output + i * hidden_size;
const scalar_t* __restrict__ input_ptr = input + i * hidden_size;
fVec sum_fvec = fVec(float(0));
float sum_val = float(0);
int64_t d;
#pragma GCC unroll 4
for (d = 0; d <= hidden_size - kVecSize; d += kVecSize) {
bVec x_bvec = bVec::loadu(input_ptr + d);
fVec x_fvec0, x_fvec1;
std::tie(x_fvec0, x_fvec1) = at::vec::convert_to_float(x_bvec);
sum_fvec += x_fvec0 * x_fvec0;
sum_fvec += x_fvec1 * x_fvec1;
}
#pragma GCC unroll 4
for (; d < hidden_size; ++d) {
float x_val = static_cast<float>(input_ptr[d]);
sum_val += x_val * x_val;
}
sum_val += vec_reduce_sum(sum_fvec);
float rsqrt_var = float(1) / std::sqrt(sum_val / hidden_size + eps);
const fVec scale_fvec = fVec(rsqrt_var);
#pragma GCC unroll 4
for (d = 0; d <= hidden_size - kVecSize; d += kVecSize) {
bVec x_bvec = bVec::loadu(input_ptr + d);
fVec x_fvec0, x_fvec1;
std::tie(x_fvec0, x_fvec1) = at::vec::convert_to_float(x_bvec);
x_fvec0 = x_fvec0 * scale_fvec;
x_fvec1 = x_fvec1 * scale_fvec;
bVec out_bvec = convert_from_float_ext<scalar_t>(x_fvec0, x_fvec1);
out_bvec.store(out_ptr + d);
}
#pragma GCC unroll 4
for (; d < hidden_size; ++d) {
float x_val = static_cast<float>(input_ptr[d]);
out_ptr[d] = static_cast<scalar_t>(x_val * rsqrt_var);
}
}
});
}
template <typename scalar_t>
void rmsnorm_kernel_impl(
scalar_t* __restrict__ output,
const scalar_t* __restrict__ input,
const scalar_t* __restrict__ weight,
int64_t batch_size,
int64_t hidden_size,
int64_t input_strideN,
float eps = 1e-5) {
using bVec = at::vec::Vectorized<scalar_t>;
using fVec = at::vec::Vectorized<float>;
constexpr int kVecSize = bVec::size();
at::parallel_for(0, batch_size, 0, [&](int64_t begin, int64_t end) {
for (int64_t i = begin; i < end; ++i) {
// local ptrs
scalar_t* __restrict__ out_ptr = output + i * hidden_size;
const scalar_t* __restrict__ input_ptr = input + i * input_strideN;
fVec sum_fvec = fVec(float(0));
float sum_val = float(0);
int64_t d;
#pragma GCC unroll 4
for (d = 0; d <= hidden_size - kVecSize; d += kVecSize) {
bVec x_bvec = bVec::loadu(input_ptr + d);
fVec x_fvec0, x_fvec1;
std::tie(x_fvec0, x_fvec1) = at::vec::convert_to_float(x_bvec);
sum_fvec += x_fvec0 * x_fvec0;
sum_fvec += x_fvec1 * x_fvec1;
}
#pragma GCC unroll 4
for (; d < hidden_size; ++d) {
float x_val = static_cast<float>(input_ptr[d]);
sum_val += x_val * x_val;
}
sum_val += vec_reduce_sum(sum_fvec);
float rsqrt_var = float(1) / std::sqrt(sum_val / hidden_size + eps);
const fVec scale_fvec = fVec(rsqrt_var);
#pragma GCC unroll 4
for (d = 0; d <= hidden_size - kVecSize; d += kVecSize) {
bVec x_bvec = bVec::loadu(input_ptr + d);
fVec x_fvec0, x_fvec1;
std::tie(x_fvec0, x_fvec1) = at::vec::convert_to_float(x_bvec);
bVec w_bvec = bVec::loadu(weight + d);
fVec w_fvec0, w_fvec1;
std::tie(w_fvec0, w_fvec1) = at::vec::convert_to_float(w_bvec);
x_fvec0 = x_fvec0 * scale_fvec * w_fvec0;
x_fvec1 = x_fvec1 * scale_fvec * w_fvec1;
bVec out_bvec = convert_from_float_ext<scalar_t>(x_fvec0, x_fvec1);
out_bvec.store(out_ptr + d);
}
#pragma GCC unroll 4
for (; d < hidden_size; ++d) {
float x_val = static_cast<float>(input_ptr[d]);
float w_val = static_cast<float>(weight[d]);
out_ptr[d] = static_cast<scalar_t>(x_val * rsqrt_var * w_val);
}
}
});
}
template <typename scalar_t>
void fused_add_rmsnorm_kernel_impl(
scalar_t* __restrict__ input,
scalar_t* __restrict__ residual,
const scalar_t* __restrict__ weight,
float* __restrict__ buffer,
int64_t batch_size,
int64_t hidden_size,
int64_t input_strideN,
float eps = 1e-5) {
using bVec = at::vec::Vectorized<scalar_t>;
using fVec = at::vec::Vectorized<float>;
constexpr int kVecSize = bVec::size();
at::parallel_for(0, batch_size, 0, [&](int64_t begin, int64_t end) {
int tid = at::get_thread_num();
float* __restrict__ buffer_ptr = buffer + tid * hidden_size;
for (int64_t i = begin; i < end; ++i) {
// local ptrs
scalar_t* __restrict__ input_ptr = input + i * input_strideN;
scalar_t* __restrict__ residual_ptr = residual + i * hidden_size;
fVec sum_fvec = fVec(float(0));
float sum_val = float(0);
int64_t d;
#pragma GCC unroll 4
for (d = 0; d <= hidden_size - kVecSize; d += kVecSize) {
bVec x_bvec = bVec::loadu(input_ptr + d);
fVec x_fvec0, x_fvec1;
std::tie(x_fvec0, x_fvec1) = at::vec::convert_to_float(x_bvec);
bVec r_bvec = bVec::loadu(residual_ptr + d);
fVec r_fvec0, r_fvec1;
std::tie(r_fvec0, r_fvec1) = at::vec::convert_to_float(r_bvec);
x_fvec0 += r_fvec0;
x_fvec1 += r_fvec1;
bVec out_bvec = convert_from_float_ext<scalar_t>(x_fvec0, x_fvec1);
out_bvec.store(residual_ptr + d);
sum_fvec += x_fvec0 * x_fvec0;
sum_fvec += x_fvec1 * x_fvec1;
x_fvec0.store(buffer_ptr + d);
x_fvec1.store(buffer_ptr + d + fVec::size());
}
#pragma GCC unroll 4
for (; d < hidden_size; ++d) {
float x_val = static_cast<float>(input_ptr[d]);
float r_val = static_cast<float>(residual_ptr[d]);
x_val += r_val;
residual_ptr[d] = static_cast<scalar_t>(x_val);
sum_val += x_val * x_val;
buffer_ptr[d] = x_val;
}
sum_val += vec_reduce_sum(sum_fvec);
float rsqrt_var = float(1) / std::sqrt(sum_val / hidden_size + eps);
const fVec scale_fvec = fVec(rsqrt_var);
#pragma GCC unroll 4
for (d = 0; d <= hidden_size - kVecSize; d += kVecSize) {
fVec x_fvec0 = fVec::loadu(buffer_ptr + d);
fVec x_fvec1 = fVec::loadu(buffer_ptr + d + fVec::size());
bVec w_bvec = bVec::loadu(weight + d);
fVec w_fvec0, w_fvec1;
std::tie(w_fvec0, w_fvec1) = at::vec::convert_to_float(w_bvec);
x_fvec0 = x_fvec0 * scale_fvec * w_fvec0;
x_fvec1 = x_fvec1 * scale_fvec * w_fvec1;
bVec x_bvec = convert_from_float_ext<scalar_t>(x_fvec0, x_fvec1);
x_bvec.store(input_ptr + d);
}
#pragma GCC unroll 4
for (; d < hidden_size; ++d) {
float x_val = buffer_ptr[d] * rsqrt_var * static_cast<float>(weight[d]);
input_ptr[d] = x_val;
}
}
});
}
} // anonymous namespace
// input : {batch_size, hidden_size}
at::Tensor l2norm_cpu(at::Tensor& input, double eps) {
RECORD_FUNCTION("sgl-kernel::l2norm_cpu", std::vector<c10::IValue>({input}));
CHECK_INPUT(input);
CHECK_DIM(2, input);
int64_t batch_size = input.size(0);
int64_t hidden_size = input.size(1);
at::Tensor output = at::empty_like(input);
AT_DISPATCH_REDUCED_FLOATING_TYPES(input.scalar_type(), "l2norm_kernel", [&] {
l2norm_kernel_impl<scalar_t>(output.data_ptr<scalar_t>(), input.data_ptr<scalar_t>(), batch_size, hidden_size, eps);
});
return output;
}
// input : {batch_size, hidden_size}
// weight: {hidden_size}
at::Tensor rmsnorm_cpu(at::Tensor& input, at::Tensor& weight, double eps) {
RECORD_FUNCTION("sgl-kernel::rmsnorm_cpu", std::vector<c10::IValue>({input, weight}));
CHECK_LAST_DIM_CONTIGUOUS_INPUT(input);
CHECK_INPUT(weight);
CHECK_DIM(2, input);
CHECK_DIM(1, weight);
CHECK_EQ(input.size(1), weight.size(0));
int64_t batch_size = input.size(0);
int64_t hidden_size = input.size(1);
at::Tensor output = at::empty_like(input);
int64_t input_strideN = input.stride(0);
AT_DISPATCH_REDUCED_FLOATING_TYPES(input.scalar_type(), "rmsnorm_kernel", [&] {
rmsnorm_kernel_impl<scalar_t>(
output.data_ptr<scalar_t>(),
input.data_ptr<scalar_t>(),
weight.data_ptr<scalar_t>(),
batch_size,
hidden_size,
input_strideN,
eps);
});
return output;
}
// input : {batch_size, hidden_size}
// residual: {batch_size, hidden_size}
// weight : {hidden_size}
void fused_add_rmsnorm_cpu(at::Tensor& input, at::Tensor& residual, at::Tensor& weight, double eps) {
RECORD_FUNCTION("sgl-kernel::fused_add_rmsnorm_cpu", std::vector<c10::IValue>({input, residual, weight}));
CHECK_LAST_DIM_CONTIGUOUS_INPUT(input);
CHECK_INPUT(residual);
CHECK_INPUT(weight);
CHECK_DIM(2, input);
CHECK_DIM(2, residual);
CHECK_DIM(1, weight);
CHECK_EQ(input.size(0), residual.size(0));
CHECK_EQ(input.size(1), residual.size(1));
CHECK_EQ(input.size(1), weight.size(0));
int64_t batch_size = input.size(0);
int64_t hidden_size = input.size(1);
int64_t input_strideN = input.stride(0);
// allocate temp buffer to store x in float32 per thread
// TODO: implement a singleton for context
int64_t num_threads = at::get_num_threads();
at::Tensor buffer = at::empty({num_threads, hidden_size}, input.options().dtype(at::kFloat));
AT_DISPATCH_REDUCED_FLOATING_TYPES(input.scalar_type(), "fused_add_rmsnorm_kernel", [&] {
fused_add_rmsnorm_kernel_impl<scalar_t>(
input.data_ptr<scalar_t>(),
residual.data_ptr<scalar_t>(),
weight.data_ptr<scalar_t>(),
buffer.data_ptr<float>(),
batch_size,
hidden_size,
input_strideN,
eps);
});
}