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

120 lines
3.2 KiB
C++

#include <ATen/record_function.h>
#include <torch/all.h>
#include "shm.h"
// Communication settings
static int world_rank = -1;
static int world_size = -1;
static bool is_initialized = false;
static bool all_ranks_local_p = false;
void initialize(int64_t size, int64_t rank) {
if (is_initialized) {
return;
}
// Check whether all ranks is on the same physical machine.
// If true, we will use an SHM based low latency allreduce
auto ls_string = std::getenv("LOCAL_SIZE");
int ls = 0;
if (ls_string != NULL) {
ls = std::stoi(std::getenv("LOCAL_SIZE"));
}
if (size >= 1 && size == ls) {
all_ranks_local_p = true;
}
world_size = size;
world_rank = rank;
is_initialized = true;
const char* addr_string = std::getenv("MASTER_ADDR");
if (addr_string == NULL) {
addr_string = "";
}
const char* port_string = std::getenv("MASTER_PORT");
if (port_string == NULL) {
port_string = "";
}
if (all_ranks_local_p) {
shm_initialize(size, rank, addr_string, port_string);
}
}
void shm_allreduce(
torch::Tensor& data, c10::intrusive_ptr<c10d::ProcessGroup> process_group, c10::intrusive_ptr<c10d::ReduceOp> op) {
RECORD_FUNCTION("sgl-kernel::shm_allreduce", std::vector<c10::IValue>({data}));
TORCH_CHECK(op == c10d::ReduceOp::SUM, "Only torch.distributed.ReduceOp.SUM is supported");
auto numel = data.numel();
int data_size = 0;
bool data_type_fallback = false;
switch (data.scalar_type()) {
case c10::ScalarType::BFloat16:
data_size = numel * 2;
break;
case c10::ScalarType::Float:
data_size = numel * 4;
break;
default:
data_type_fallback = true;
}
if (data_type_fallback || !all_ranks_local_p) {
// Fallback to torch distributed allreduce
std::vector<torch::Tensor> tensors = {data};
process_group->allreduce(tensors)->wait();
} else {
all_reduce_outer_loop(data, numel, data_size);
}
return;
}
torch::Tensor shm_allgather(torch::Tensor& data, c10::intrusive_ptr<c10d::ProcessGroup> process_group, int64_t dim) {
RECORD_FUNCTION("sgl-kernel::shm_allgather", std::vector<c10::IValue>({data}));
auto numel = data.numel();
int data_size = 0;
bool data_type_fallback = false;
switch (data.scalar_type()) {
case c10::ScalarType::BFloat16:
data_size = numel * 2;
break;
case c10::ScalarType::Float:
data_size = numel * 4;
break;
default:
data_type_fallback = true;
}
if (dim < 0) {
dim += data.dim();
}
if (data_type_fallback || !all_ranks_local_p) {
// Fallback to torch distributed allreduce
std::vector<std::vector<torch::Tensor>> output_tensors(1);
auto world_size = process_group->getSize();
for (int i = 0; i < world_size; i++) {
output_tensors[0].push_back(torch::empty_like(data));
}
std::vector<torch::Tensor> input_tensors = {data};
process_group->allgather(output_tensors, input_tensors)->wait();
return torch::cat(output_tensors[0], dim).contiguous();
}
std::vector<int64_t> result_shape = data.sizes().vec();
result_shape[dim] *= world_size;
torch::Tensor result_tensor = torch::empty(result_shape, data.options());
return all_gather(result_tensor, data, dim, numel, data_size);
}