Skip to content

GitLab

Commit 226a1b72 authored by Tri Dao's avatar Tri Dao
Browse files

Implement TensorParallel for FusedDense and FusedDenseGeluDense

parent dff68c2b
Hide whitespace changes
Inline Side-by-side
Showing with 502 additions and 59 deletions
csrc/fused_dense_lib/fused_dense.cpp
View file @ 226a1b72
......@@ -2,6 +2,7 @@
// We make it work for bfloat16
#include <torch/extension.h>
#include <torch/torch.h>
#include <c10/cuda/CUDAGuard.h>
#include <vector>
#include <stdio.h>
......@@ -50,6 +51,10 @@ std::vector<at::Tensor> linear_bias_wgrad(at::Tensor input, at::Tensor d_output,
CHECK_SHAPE(input, batch_size, in_features);
CHECK_SHAPE(d_output, batch_size, out_features);
// Otherwise the kernel will be launched from cuda:0 device
// Cast to char to avoid compiler warning about narrowing
at::cuda::CUDAGuard device_guard{(char)input.get_device()};
// create output/workspace tensor
auto opts = input.options();
auto d_weight = at::empty({out_features, in_features}, opts);
......@@ -104,6 +109,10 @@ std::vector<at::Tensor> linear_gelu_forward(at::Tensor input, at::Tensor weight,
CHECK_SHAPE(bias, out_features);
}
// Otherwise the kernel will be launched from cuda:0 device
// Cast to char to avoid compiler warning about narrowing
at::cuda::CUDAGuard device_guard{(char)input.get_device()};
// create output/workspace tensor
auto opts = input.options();
auto output = at::empty({batch_size, out_features}, opts);
......@@ -153,6 +162,10 @@ std::vector<at::Tensor> bias_gelu_linear_dgrad_bgrad(
CHECK_SHAPE(d_output, batch_size, out_features);
CHECK_SHAPE(gelu_in, batch_size, in_features);
// Otherwise the kernel will be launched from cuda:0 device
// Cast to char to avoid compiler warning about narrowing
at::cuda::CUDAGuard device_guard{(char)weight.get_device()};
// create output/workspace tensor
auto opts = weight.options();
auto d_bias = at::empty({in_features}, opts);
......
flash_attn/modules/mlp.py
View file @ 226a1b72
......@@ -5,9 +5,9 @@ import torch.nn as nn
import torch.nn.functional as F
try:
from flash_attn.ops.fused_dense import FusedDenseGeluDense
from flash_attn.ops.fused_dense import FusedDenseGeluDense, ParallelFusedDenseGeluDense
except ImportError:
FusedDenseGeluDense = None
FusedDenseGeluDense, ParallelFusedDenseGeluDense = None, None
class Mlp(nn.Module):
......
flash_attn/ops/fused_dense.py
View file @ 226a1b72
# Adapted from https://github.com/NVIDIA/apex/blob/master/apex/fused_dense/fused_dense.py
# Copyright (c) 2022, Tri Dao.
# Inspired by https://github.com/NVIDIA/apex/blob/master/apex/fused_dense/fused_dense.py
# We make it work with pytorch amp and with bfloat16.
# The TensorParallel linear modules are inspired by https://github.com/NVIDIA/apex/blob/master/apex/transformer/tensor_parallel/layers.py
from typing import Optional
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch import Tensor
from torch.distributed import ProcessGroup
from torch.cuda.amp import custom_bwd, custom_fwd
# import fused_dense_cuda # from apex
import fused_dense_lib as fused_dense_cuda
from flash_attn.ops.gelu_activation import gelu_bwd
from flash_attn.utils.distributed import all_gather_raw, reduce_scatter_raw, reduce_scatter
class FusedDenseFunc(torch.autograd.Function):
@staticmethod
@custom_fwd
def forward(ctx, x, weight, bias, return_residual=False):
def forward(ctx, x, weight, bias, return_residual=False, process_group=None):
"""
If process_group is not None, we're doing Tensor Parallel with sequence parallelism:
we do an all_gather_raw of x before doing the matmul.
"""
if torch.is_autocast_enabled():
dtype = torch.get_autocast_gpu_dtype()
x, weight = [a.to(dtype=dtype) for a in [x, weight]]
bias = bias.to(dtype=dtype) if bias is not None else None
ctx.return_residual = return_residual
ctx.process_group = process_group
ctx.compute_weight_gradient = weight.requires_grad
x = x.contiguous()
weight = weight.contiguous()
ctx.save_for_backward(x, weight)
if ctx.compute_weight_gradient:
ctx.save_for_backward(x, weight)
else:
ctx.save_for_backward(weight)
batch_shape, n = x.shape[:-1], x.shape[-1]
batch_dim = batch_shape.numel()
assert batch_dim <= 64 * 1024, 'fused_dense only supports dimension at most 64k'
output = F.linear(x, weight, bias)
if process_group is not None:
total_x, _ = all_gather_raw(x, process_group)
else:
total_x = x
output = F.linear(total_x, weight, bias)
return output if not return_residual else (output, x)
@staticmethod
......@@ -39,37 +59,56 @@ class FusedDenseFunc(torch.autograd.Function):
if ctx.return_residual:
grad_input, = args
grad_input = grad_input.contiguous()
x, weight = ctx.saved_tensors
batch_shape, n = x.shape[:-1], x.shape[-1]
process_group = ctx.process_group
if ctx.compute_weight_gradient:
x, weight = ctx.saved_tensors
if process_group is not None:
total_x, handle_x = all_gather_raw(x, process_group, async_op=True)
else:
total_x = x
else:
weight, = ctx.saved_tensors
total_x = None
batch_shape = grad_output.shape[:-1]
batch_dim = batch_shape.numel()
grad_output = grad_output.reshape(batch_dim, grad_output.shape[-1])
if ctx.needs_input_grad[1]:
grad_weight, grad_bias = fused_dense_cuda.linear_bias_wgrad(
x.reshape(batch_dim, n), grad_output, ctx.needs_input_grad[2]
)
else:
grad_weight = None
grad_bias = grad_output if ctx.needs_input_grad[2] else None
if ctx.needs_input_grad[0]:
if not ctx.return_residual:
grad_input = F.linear(grad_output, weight.t())
else:
grad_input = torch.addmm(grad_input.reshape(batch_dim, n), grad_output, weight)
grad_input = grad_input.reshape_as(x)
grad_input = torch.addmm(grad_input.reshape(batch_dim, grad_input.shape[-1]),
grad_output, weight)
grad_input = grad_input.reshape(*batch_shape, grad_input.shape[-1])
if process_group is not None:
grad_input, handle_grad_input = reduce_scatter_raw(grad_input, process_group,
async_op=True)
else:
grad_input = None
return grad_input, grad_weight, grad_bias, None
if ctx.needs_input_grad[1]:
assert ctx.compute_weight_gradient
if process_group is not None:
handle_x.wait()
grad_weight, grad_bias = fused_dense_cuda.linear_bias_wgrad(
total_x.reshape(batch_dim, total_x.shape[-1]), grad_output, ctx.needs_input_grad[2]
)
else:
grad_weight = None
grad_bias = grad_output if ctx.needs_input_grad[2] else None
if process_group is not None and ctx.needs_input_grad[0]:
handle_grad_input.wait()
return grad_input, grad_weight, grad_bias, None, None
def fused_dense_func(x: Tensor, weight: Tensor, bias: Optional[Tensor] = None,
return_residual: bool = False):
return_residual: bool = False, process_group: Optional[ProcessGroup] = None):
batch_dim = x.shape[:-1].numel()
dtype_eligible = (x.dtype in [torch.float16, torch.bfloat16]
or (x.dtype == torch.float32 and torch.is_autocast_enabled()))
if (x.is_cuda and weight.is_cuda and (bias is None or bias.is_cuda) and batch_dim <= 64 * 1024
and dtype_eligible):
return FusedDenseFunc.apply(x, weight, bias, return_residual)
return FusedDenseFunc.apply(x, weight, bias, return_residual, process_group)
else:
assert process_group is None
out = F.linear(x, weight, bias)
return out if not return_residual else (out, x)
......@@ -81,17 +120,69 @@ class FusedDense(nn.Linear):
super().__init__(in_features, out_features, bias=bias, device=device, dtype=dtype)
self.return_residual = return_residual
def forward(self, x, process_group=None):
"""
If process_group is not None, we're doing Tensor Parallel with sequence parallelism:
we do an all_gather of x before doing the matmul.
"""
return fused_dense_func(x, self.weight, self.bias, return_residual=self.return_residual,
process_group=process_group)
class ColumnParallelLinear(nn.Linear):
def __init__(self, in_features: int, out_features: int, process_group: ProcessGroup,
bias: bool = True, device=None, dtype=None) -> None:
world_size = torch.distributed.get_world_size(process_group)
if out_features % world_size != 0:
raise ValueError(f'out_features ({out_features}) must be divisible by '
f'world_size ({world_size})')
super().__init__(in_features, out_features // world_size, bias=bias,
device=device, dtype=dtype)
self.process_group = process_group
def forward(self, x):
return fused_dense_func(x, self.weight, self.bias, return_residual=self.return_residual)
"""
We're doing Tensor Parallel with sequence parallelism: we do an all_gather of
x before doing the matmul.
"""
return fused_dense_func(x, self.weight, self.bias, process_group=self.process_group)
class RowParallelLinear(nn.Linear):
def __init__(self, in_features: int, out_features: int, process_group: ProcessGroup,
bias: bool = True, device=None, dtype=None) -> None:
world_size = torch.distributed.get_world_size(process_group)
rank = torch.distributed.get_rank(process_group)
if in_features % world_size != 0:
raise ValueError(f'in_features ({in_features}) must be divisible by '
f'world_size ({world_size})')
# Only rank 0 will have bias
super().__init__(in_features // world_size, out_features, bias=bias and rank == 0,
device=device, dtype=dtype)
self.process_group = process_group
def forward(self, x):
"""
We're doing Tensor Parallel with sequence parallelism: we do the matmul and then
a reduce_scatter of the result.
"""
out = fused_dense_func(x, self.weight, self.bias)
return reduce_scatter(out, self.process_group)
class FusedDenseGeluDenseFunc(torch.autograd.Function):
@staticmethod
@custom_fwd
def forward(ctx, x, weight1, bias1, weight2, bias2, save_gelu_in=True, return_residual=False,
checkpoint_lvl=0, heuristic=0):
"""checkpoint_lvl:
def forward(ctx, x, weight1, bias1, weight2, bias2, save_pre_act=True, return_residual=False,
checkpoint_lvl=0, heuristic=0, process_group=None):
"""
If process_group is not None, we're doing Tensor Parallel with sequence parallelism:
we do an all_gather of x before doing the matmul.
checkpoint_lvl:
0: no recomputation in the bwd
1: recompute gelu_out in the bwd
2: recompute gelu_in and gelu_out in the bwd
......@@ -102,28 +193,34 @@ class FusedDenseGeluDenseFunc(torch.autograd.Function):
x, weight1, weight2 = [a.to(dtype=dtype) for a in [x, weight1, weight2]]
bias1 = bias1.to(dtype=dtype) if bias1 is not None else None
bias2 = bias2.to(dtype=dtype) if bias2 is not None else None
if not save_gelu_in:
if not save_pre_act:
checkpoint_lvl = 2
assert checkpoint_lvl in [0, 1, 2]
ctx.return_residual = return_residual
ctx.process_group = process_group
x = x.contiguous()
weight1 = weight1.contiguous()
bias1 = bias1.contiguous() if bias1 is not None else None
weight2 = weight2.contiguous()
bias2 = bias2.contiguous() if bias2 is not None else None
batch_shape, n = x.shape[:-1], x.shape[-1]
if process_group is not None:
total_x, _ = all_gather_raw(x, process_group)
else:
total_x = x
batch_shape, n = total_x.shape[:-1], total_x.shape[-1]
batch_dim = batch_shape.numel()
assert batch_dim <= 64 * 1024, 'fused_dense only supports dimension at most 64k'
if heuristic == -1:
gelu_in = F.linear(x, weight1, bias1)
gelu_in = F.linear(total_x, weight1, bias1)
output1 = F.gelu(gelu_in, approximate='tanh')
# gelu_in = F.linear(x.reshape(batch_dim, n), weight1) # This is before adding bias1
# gelu_in = F.linear(total_x.reshape(batch_dim, n), weight1) # This is before adding bias1
# with torch.jit.fuser('fuser2'):
# output1 = bias_gelu(gelu_in, bias1)
else:
output1, *rest = fused_dense_cuda.linear_gelu_forward(x.reshape(batch_dim, n), weight1,
bias1, save_gelu_in, heuristic)
if save_gelu_in:
output1, *rest = fused_dense_cuda.linear_gelu_forward(
total_x.reshape(batch_dim, n), weight1, bias1, save_pre_act, heuristic
)
if save_pre_act:
gelu_in = rest[0]
output2 = F.linear(output1, weight2, bias2)
ctx.checkpoint_lvl = checkpoint_lvl
......@@ -145,22 +242,31 @@ class FusedDenseGeluDenseFunc(torch.autograd.Function):
if ctx.return_residual:
grad_input, = args
grad_input = grad_input.contiguous()
process_group = ctx.process_group
x, weight1, weight2, *rest = ctx.saved_tensors
batch_shape, n = x.shape[:-1], x.shape[-1]
if process_group is None:
total_x = x
batch_shape = grad_output.shape[:-1]
batch_dim = batch_shape.numel()
if checkpoint_lvl == 0:
gelu_in, output1 = rest
elif checkpoint_lvl == 1:
gelu_in, = rest
output1 = F.gelu(gelu_in, approximate='tanh')
if checkpoint_lvl in [0, 1]:
if process_group is not None:
total_x, handle_x = all_gather_raw(x, process_group, async_op=True)
if checkpoint_lvl == 0:
gelu_in, output1 = rest
elif checkpoint_lvl == 1:
gelu_in, = rest
output1 = F.gelu(gelu_in, approximate='tanh')
elif checkpoint_lvl == 2:
bias1, = rest
if process_group is not None:
total_x, _ = all_gather_raw(x, process_group)
if ctx.heuristic == -1:
gelu_in = F.linear(x, weight1, bias1)
gelu_in = F.linear(total_x, weight1, bias1)
output1 = F.gelu(gelu_in, approximate='tanh')
else:
output1, gelu_in = fused_dense_cuda.linear_gelu_forward(
x.reshape(batch_dim, n), weight1, bias1, True, ctx.heuristic
total_x.reshape(batch_dim, total_x.shape[-1]), weight1, bias1, True,
ctx.heuristic
)
grad_output = grad_output.reshape(batch_dim, grad_output.shape[-1])
......@@ -178,13 +284,6 @@ class FusedDenseGeluDenseFunc(torch.autograd.Function):
grad_output1 = F.linear(grad_output, weight2.t())
with torch.jit.fuser('fuser2'):
grad_gelu = gelu_bwd(grad_output1, gelu_in)
if ctx.needs_input_grad[1]:
grad_weight1, grad_bias1 = fused_dense_cuda.linear_bias_wgrad(
x.reshape(batch_dim, n), grad_gelu, ctx.needs_input_grad[2]
)
else:
grad_weight1 = None
grad_bias1 = grad_gelu if ctx.needs_input_grad[2] else None
else:
# The cublasLt epilogue has to compute both gelu grad and bias grad, we can't
# just compute gelu grad
......@@ -193,26 +292,49 @@ class FusedDenseGeluDenseFunc(torch.autograd.Function):
)
if not ctx.needs_input_grad[2]:
grad_bias1 = None
if ctx.needs_input_grad[1]:
grad_weight1 = F.linear(grad_gelu.t(), x.reshape(batch_dim, n).t())
else:
grad_weight1 = None
if ctx.needs_input_grad[0]:
if not ctx.return_residual:
grad_input = F.linear(grad_gelu, weight1.t())
else:
grad_input = torch.addmm(grad_input.reshape(batch_dim, n), grad_gelu, weight1)
grad_input = grad_input.reshape_as(x)
grad_input = torch.addmm(grad_input.reshape(batch_dim, grad_input.shape[-1]),
grad_gelu, weight1)
grad_input = grad_input.reshape(*batch_shape, grad_input.shape[-1])
if process_group is not None:
grad_input, handle_grad_input = reduce_scatter_raw(grad_input, process_group,
async_op=True)
else:
grad_input = None
return grad_input, grad_weight1, grad_bias1, grad_weight2, grad_bias2, None, None, None, None
if ctx.heuristic == -1:
if ctx.needs_input_grad[1]:
if process_group is not None:
handle_x.wait()
grad_weight1, grad_bias1 = fused_dense_cuda.linear_bias_wgrad(
total_x.reshape(batch_dim, total_x.shape[-1]), grad_gelu,
ctx.needs_input_grad[2]
)
else:
grad_weight1 = None
grad_bias1 = grad_gelu if ctx.needs_input_grad[2] else None
else:
if ctx.needs_input_grad[1]:
if process_group is not None:
handle_x.wait()
grad_weight1 = F.linear(grad_gelu.t(),
total_x.reshape(batch_dim, total_x.shape[-1]).t())
else:
grad_weight1 = None
if process_group is not None and ctx.needs_input_grad[0]:
handle_grad_input.wait()
return (grad_input, grad_weight1, grad_bias1, grad_weight2, grad_bias2,
None, None, None, None, None)
def fused_dense_gelu_dense_func(
x: Tensor, weight1: Tensor, weight2: Tensor, bias1: Optional[Tensor] = None,
bias2: Optional[Tensor] = None,
save_gelu_in: bool = True, return_residual: bool = False,
checkpoint_lvl: int = 0, heuristic: int = 0
save_pre_act: bool = True, return_residual: bool = False,
checkpoint_lvl: int = 0, heuristic: int = 0,
process_group: Optional[ProcessGroup] = None
):
batch_dim = x.shape[:-1].numel()
dtype_eligible = (x.dtype in [torch.float16, torch.bfloat16]
......@@ -222,9 +344,10 @@ def fused_dense_gelu_dense_func(
and dtype_eligible):
return FusedDenseGeluDenseFunc.apply(
x, weight1, bias1, weight2, bias2,
save_gelu_in, return_residual, checkpoint_lvl, heuristic
save_pre_act, return_residual, checkpoint_lvl, heuristic, process_group
)
else:
assert process_group is None
gelu_in = F.linear(x, weight1, bias1)
output1 = F.gelu(gelu_in, approximate='tanh')
output2 = F.linear(output1, weight2, bias2)
......@@ -237,6 +360,10 @@ class FusedDenseGeluDense(nn.Module):
bias2=True, return_residual=False, checkpoint_lvl=0, heuristic=0,
device=None, dtype=None):
"""
If process_group is not None, we're doing Tensor Parallel with sequence parallelism:
we do an all_gather of x before doing the matmul, gelu, then matmul.
Finally we do a reduce_scatter of the output.
checkpoint_lvl (increasing lvl means slower but more memory saving):
0: no recomputation in the bwd
1: recompute gelu_out in the bwd
......@@ -261,9 +388,58 @@ class FusedDenseGeluDense(nn.Module):
self.fc1 = nn.Linear(in_features, hidden_features, bias=bias1, **factory_kwargs)
self.fc2 = nn.Linear(hidden_features, out_features, bias=bias2, **factory_kwargs)
def forward(self, x, process_group=None):
out = fused_dense_gelu_dense_func(
x, self.fc1.weight, self.fc2.weight, self.fc1.bias, self.fc2.bias,
save_pre_act=self.training, return_residual=self.return_residual,
checkpoint_lvl=self.checkpoint_lvl, heuristic=self.heuristic,
process_group=process_group
)
if self.return_residual:
out, x = out
if process_group is not None:
out = reduce_scatter(out, process_group)
return out if not self.return_residual else (out, x)
class ParallelFusedDenseGeluDense(nn.Module):
def __init__(self, in_features, hidden_features, out_features=None,
process_group: ProcessGroup = None, bias1=True, bias2=True,
checkpoint_lvl=0, heuristic=0, device=None, dtype=None):
"""
process_group is required. We're doing Tensor Parallel with sequence parallelism:
we do an all_gather of x before doing the matmul, gelu, then matmul.
Finally we do a reduce_scatter of the output.
checkpoint_lvl (increasing lvl means slower but more memory saving):
0: no recomputation in the bwd
1: recompute gelu_out in the bwd
2: recompute gelu_in and gelu_out in the bwd
heuristic:
-1: don't fuse gemm + gelu (separate kernel)
0..4: use this heuristic for the algo section in the fused gemm + gelu
For CUDA >= 11.8, you'd want heuristic=0 for both fp16 and bf16 for best perf.
For CUDA <= 11.7, you'd want heuristic=1 for fp16 and heuristic=-1 for bf16.
"""
assert checkpoint_lvl in [0, 1, 2]
assert process_group is not None
factory_kwargs = {'device': device, 'dtype': dtype}
super().__init__()
if out_features is None:
out_features = in_features
self.process_group = process_group
self.checkpoint_lvl = checkpoint_lvl
self.heuristic = heuristic
self.fc1 = ColumnParallelLinear(in_features, hidden_features, process_group,
bias=bias1, **factory_kwargs)
self.fc2 = RowParallelLinear(hidden_features, out_features, process_group,
bias=bias2, **factory_kwargs)
def forward(self, x):
return fused_dense_gelu_dense_func(
out = fused_dense_gelu_dense_func(
x, self.fc1.weight, self.fc2.weight, self.fc1.bias, self.fc2.bias,
save_gelu_in=self.training, return_residual=self.return_residual,
checkpoint_lvl=self.checkpoint_lvl, heuristic=self.heuristic
save_pre_act=self.training, checkpoint_lvl=self.checkpoint_lvl,
heuristic=self.heuristic, process_group=self.process_group
)
return reduce_scatter(out, self.process_group)
flash_attn/utils/distributed.py 0 → 100644
View file @ 226a1b72
from typing import Optional
import torch
from torch import Tensor
from torch.distributed import ProcessGroup
# `all_gather_into_tensor` and `reduce_scatter_tensor` are new placeholders for
# `_all_gather_base` and `_reduce_scatter_base`. They require the most recent
# version of PyTorch. The following 4 lines are for backward compatibility with
# older PyTorch.
if "all_gather_into_tensor" not in dir(torch.distributed):
torch.distributed.all_gather_into_tensor = torch.distributed._all_gather_base
if "reduce_scatter_tensor" not in dir(torch.distributed):
torch.distributed.reduce_scatter_tensor = torch.distributed._reduce_scatter_base
# Raw operation, oes does support autograd, but does support async
def all_gather_raw(input_: Tensor, process_group: ProcessGroup, async_op: bool = False):
world_size = torch.distributed.get_world_size(process_group)
output = torch.empty(world_size * input_.shape[0], *input_.shape[1:],
dtype=input_.dtype, device=input_.device)
handle = torch.distributed.all_gather_into_tensor(output, input_.contiguous(),
group=process_group, async_op=async_op)
return output, handle
# Raw operation, oes does support autograd, but does support async
def reduce_scatter_raw(input_: Tensor, process_group: ProcessGroup, async_op: bool = False):
world_size = torch.distributed.get_world_size(process_group)
assert input_.shape[0] % world_size == 0
output = torch.empty(input_.shape[0] // world_size, *input_.shape[1:],
dtype=input_.dtype, device=input_.device)
handle = torch.distributed.reduce_scatter_tensor(output, input_.contiguous(),
group=process_group,
async_op=async_op)
return output, handle
class AllGatherFunc(torch.autograd.Function):
"""Gather the input from sequence parallel region and concatenate."""
@staticmethod
def forward(ctx, input_: Tensor, process_group: ProcessGroup) -> Tensor:
ctx.process_group = process_group
output, _ = all_gather_raw(input_, process_group)
return output
@staticmethod
def backward(ctx, grad_output: Tensor):
grad_input, _ = reduce_scatter_raw(grad_output, ctx.process_group)
return grad_input, None
# Supports autograd, but does not support async
all_gather = AllGatherFunc.apply
class ReduceScatterFunc(torch.autograd.Function):
"""Reduce scatter the input from the sequence parallel region and concatenate."""
@staticmethod
def forward(ctx, input_: Tensor, process_group: ProcessGroup) -> Tensor:
ctx.process_group = process_group
output, _ = reduce_scatter_raw(input_, process_group)
return output
@staticmethod
def backward(ctx, grad_output: Tensor):
grad_input, _ = all_gather_raw(grad_output, ctx.process_group)
return grad_input, None
# Supports autograd, but does not support async
reduce_scatter = ReduceScatterFunc.apply
tests/ops/test_fused_dense_parallel.py 0 → 100644
View file @ 226a1b72
# Run test with:
# torchrun --no_python --nproc_per_node=8 pytest -q -s tests/ops/test_fused_dense_parallel.py
import math
import torch
import torch.nn.functional as F
import pytest
from apex.transformer import parallel_state
from apex.transformer import tensor_parallel
from flash_attn.ops.fused_dense import FusedDense, FusedDenseGeluDense
from flash_attn.ops.fused_dense import ColumnParallelLinear, ParallelFusedDenseGeluDense
is_sm8x = torch.cuda.get_device_capability('cuda')[0] >= 8
@pytest.mark.parametrize('dtype', [torch.float16] + ([torch.bfloat16] if is_sm8x else []))
# @pytest.mark.parametrize('dtype', [torch.bfloat16])
@pytest.mark.parametrize('world_size', [1, 2, 4, 8])
# @pytest.mark.parametrize('world_size', [8])
@pytest.mark.parametrize('has_bias', [True, False])
# @pytest.mark.parametrize('has_bias', [True])
@pytest.mark.parametrize('out_features', [1024, 4096])
# @pytest.mark.parametrize('out_features', [1024])
@pytest.mark.parametrize('in_features', [1024, 4096])
# @pytest.mark.parametrize('in_features', [4096])
def test_fused_linear_bias(in_features, out_features, has_bias, world_size, dtype):
assert out_features % world_size == 0
rtol, atol = (3e-3, 3e-2) if dtype == torch.bfloat16 else (3e-3, 3e-3)
if not torch.distributed.is_initialized():
torch.distributed.init_process_group(backend='nccl', init_method='env://')
device = f'cuda:{torch.distributed.get_rank()}'
assert world_size <= torch.distributed.get_world_size()
parallel_state.initialize_model_parallel(tensor_model_parallel_size_=world_size)
rank = parallel_state.get_tensor_model_parallel_rank()
# set seed
torch.random.manual_seed(0)
batch_size = 8
seqlen = 512
assert batch_size * seqlen % world_size == 0
x_pt = torch.randn(batch_size * seqlen, in_features, device=device, dtype=dtype,
requires_grad=True)
x = tensor_parallel.scatter_to_sequence_parallel_region(x_pt).detach().clone().requires_grad_()
model_pt = torch.nn.Linear(in_features, out_features, bias=has_bias, device=device, dtype=dtype)
partition_out_features = out_features // world_size
model = ColumnParallelLinear(in_features, out_features,
parallel_state.get_tensor_model_parallel_group(), bias=has_bias,
device=device, dtype=dtype)
with torch.no_grad():
model.weight.copy_(
model_pt.weight[rank * partition_out_features:(rank + 1) * partition_out_features]
)
if has_bias:
model.bias.copy_(
model_pt.bias[rank * partition_out_features:(rank + 1) * partition_out_features]
)
out = model(x)
out_pt = model_pt(x_pt)
assert torch.allclose(
out, out_pt[:, rank * partition_out_features:(rank + 1) * partition_out_features],
rtol=rtol, atol=atol
)
# If we don't divide by batch_size, the gradient gets a bit too large.
g = torch.randn_like(out_pt) / 32
out_pt.backward(g)
out.backward(g[:, rank * partition_out_features:(rank + 1) * partition_out_features])
parallel_state.destroy_model_parallel()
partition_batch_dim = batch_size * seqlen // world_size
assert torch.allclose(
x.grad, x_pt.grad[rank * partition_batch_dim:(rank + 1) * partition_batch_dim],
rtol=rtol, atol=atol
)
# The error for d_weight and d_bias is quite a bit higher
assert torch.allclose(
model.weight.grad,
model_pt.weight.grad[rank * partition_out_features:(rank + 1) * partition_out_features],
rtol=rtol, atol=atol * 10
)
if has_bias:
assert torch.allclose(
model.bias.grad,
model_pt.bias.grad[rank * partition_out_features:(rank + 1) * partition_out_features],
rtol=rtol, atol=atol * 5
)
@pytest.mark.parametrize('dtype', [torch.float16] + ([torch.bfloat16] if is_sm8x else []))
# @pytest.mark.parametrize('dtype', [torch.bfloat16])
@pytest.mark.parametrize('world_size', [1, 2, 4, 8])
# @pytest.mark.parametrize('world_size', [2])
@pytest.mark.parametrize('has_bias2', [True, False])
# @pytest.mark.parametrize('has_bias2', [True])
@pytest.mark.parametrize('out_features', [1024, 4096])
# @pytest.mark.parametrize('out_features', [1024])
@pytest.mark.parametrize('in_features', [1024, 4096])
# @pytest.mark.parametrize('in_features', [1024])
def test_fused_dense_gelu_dense(in_features, out_features, has_bias2, world_size, dtype):
assert out_features % world_size == 0
rtol, atol = (3e-3, 3e-2) if dtype == torch.bfloat16 else (3e-3, 3e-3)
if not torch.distributed.is_initialized():
torch.distributed.init_process_group(backend='nccl', init_method='env://')
device = f'cuda:{torch.distributed.get_rank()}'
assert world_size <= torch.distributed.get_world_size()
parallel_state.initialize_model_parallel(tensor_model_parallel_size_=world_size)
rank = parallel_state.get_tensor_model_parallel_rank()
# set seed
torch.random.manual_seed(0)
batch_size = 8
seqlen = 512
assert batch_size * seqlen % world_size == 0
x_pt = torch.randn(batch_size * seqlen, in_features, device=device, dtype=dtype,
requires_grad=True)
# We need to generate g here so that all processes get the same gradient,
# as rank 0 will have an extra bias that changes the RNG.
# If we don't divide by batch_size, the gradient gets a bit too large.
g = torch.randn_like(x_pt) / 32
x = tensor_parallel.scatter_to_sequence_parallel_region(x_pt).detach().clone().requires_grad_()
model_pt_fc1 = torch.nn.Linear(in_features, out_features, device=device, dtype=dtype)
model_pt_fc2 = torch.nn.Linear(out_features, in_features, bias=has_bias2, device=device,
dtype=dtype)
partition_out_features = out_features // world_size
partition_in_features = in_features // world_size
model = ParallelFusedDenseGeluDense(in_features, out_features, in_features,
process_group=parallel_state.get_tensor_model_parallel_group(),
bias2=has_bias2 and rank == 0, device=device, dtype=dtype)
with torch.no_grad():
model.fc1.weight.copy_(
model_pt_fc1.weight[rank * partition_out_features:(rank + 1) * partition_out_features]
)
model.fc1.bias.copy_(
model_pt_fc1.bias[rank * partition_out_features:(rank + 1) * partition_out_features]
)
model.fc2.weight.copy_(
model_pt_fc2.weight[:, rank * partition_out_features:(rank + 1) * partition_out_features]
)
if has_bias2 and rank == 0:
model.fc2.bias.copy_(model_pt_fc2.bias)
out = model(x)
out_pt = model_pt_fc2(F.gelu(model_pt_fc1(x_pt), approximate='tanh'))
partition_batch_dim = batch_size * seqlen // world_size
assert torch.allclose(
out, out_pt[rank * partition_batch_dim:(rank + 1) * partition_batch_dim],
rtol=rtol, atol=atol
)
out_pt.backward(g)
out.backward(g[rank * partition_batch_dim:(rank + 1) * partition_batch_dim])
parallel_state.destroy_model_parallel()
assert torch.allclose(
x.grad, x_pt.grad[rank * partition_batch_dim:(rank + 1) * partition_batch_dim],
rtol=rtol, atol=atol
)
# The error for d_weight and d_bias is quite a bit higher
assert torch.allclose(
model.fc1.weight.grad,
model_pt_fc1.weight.grad[rank * partition_out_features:(rank + 1) * partition_out_features],
rtol=rtol, atol=atol * 10
)
assert torch.allclose(
model.fc1.bias.grad,
model_pt_fc1.bias.grad[rank * partition_out_features:(rank + 1) * partition_out_features],
rtol=rtol, atol=atol * 5
)
assert torch.allclose(
model.fc2.weight.grad,
model_pt_fc2.weight.grad[:, rank * partition_out_features:(rank + 1) * partition_out_features],
rtol=rtol, atol=atol * 10
)
if has_bias2 and rank == 0:
assert torch.allclose(model.fc2.bias.grad, model_pt_fc2.bias.grad, rtol=rtol, atol=atol * 5)
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment