v4.3 update. (#2709)

* v4.3 update.

* Update the cute_dsl_api changelog's doc link

* Update version to 4.3.0

* Update the example link

* Update doc to encourage user to install DSL from requirements.txt

---------

Co-authored-by: Larry Wu <larwu@nvidia.com>
This commit is contained in:
Junkai-Wu
2025-10-21 14:26:30 -04:00
committed by GitHub
co-authored by Larry Wu
parent e6e2cc29f5
commit b1d6e2c9b3
244 changed files with 59272 additions and 10455 deletions
@@ -30,17 +30,18 @@
import argparse
import operator
import time
from typing import Type, List
from functools import partial
from typing import List, Type
import cuda.bindings.driver as cuda
import torch
import cutlass
import cutlass.cute as cute
import cutlass.cute.testing as testing
import cutlass.torch as cutlass_torch
import torch
from cutlass.cute.runtime import from_dlpack
import cutlass
"""
An Elementwise Apply Example using CuTe DSL.
@@ -78,103 +79,83 @@ while maintaining high performance through efficient memory access patterns.
@cute.kernel
def elementwise_apply_kernel(
op: cutlass.Constexpr,
inputs: List[cute.Tensor],
gC: cute.Tensor,
mInputs: List[cute.Tensor],
mC: cute.Tensor,
cC: cute.Tensor, # coordinate tensor
shape: cute.Shape,
tv_layout: cute.Layout, # (tid, vid) -> logic coord
):
tidx, _, _ = cute.arch.thread_idx()
bidx, _, _ = cute.arch.block_idx()
bidx, bidy, _ = cute.arch.block_idx()
###############################################################################
# Slice to local tile of thread block
###############################################################################
blk_crd = ((None, None), (bidx, bidy))
# slice for CTAs
cta_coord = ((None, None), bidx)
# logical coord -> address
# Leverage the meta-programming capability of the DSL to slice the tensors for each input
# All for loops below on input tensors would be fully unrolled automatically at compile time
ctaInputs = [t[cta_coord] for t in inputs] # (TileM, TileN)
ctaC = gC[cta_coord] # (TileM, TileN)
ctaCrd = cC[cta_coord] # (TileM, TileN)
# logical coord -> memory address
gInputs = [t[blk_crd] for t in mInputs] # (TileM, TileN)
gC = mC[blk_crd] # (TileM, TileN)
gCrd = cC[blk_crd] # (TileM, TileN)
print(f"[DSL INFO] Sliced Tensors per thread block:")
for i in cutlass.range_constexpr(len(ctaInputs)):
print(f"[DSL INFO] ctaInputs{i} = {ctaInputs[i].type}")
print(f"[DSL INFO] ctaC = {ctaC.type}")
print(f"[DSL INFO] ctaCrd = {ctaCrd.type}")
print("[DSL INFO] Sliced Tensors per thread block:")
for i in cutlass.range_constexpr(len(gInputs)):
print(f"[DSL INFO] ctaInputs{i} = {gInputs[i].type}")
print(f"[DSL INFO] gC = {gC.type}")
print(f"[DSL INFO] gCrd = {gCrd.type}")
# compose with CTA TV layout
# (tid, vid) -> address
tidfrgInputs = [cute.composition(t, tv_layout) for t in ctaInputs]
tidfrgC = cute.composition(ctaC, tv_layout)
tidfrgCrd = cute.composition(ctaCrd, tv_layout)
# print(f"{tv_layout = }")
# print(f"{tidfrgAB[0] = }")
###############################################################################
# Compose with thread block TV layout to map thread & value indices to memory address
###############################################################################
# (tid, vid) -> memory address
tidfrgInputs = [cute.composition(t, tv_layout) for t in gInputs]
tidfrgC = cute.composition(gC, tv_layout)
tidfrgCrd = cute.composition(gCrd, tv_layout)
thr_coord = (tidx, (None, None))
# repeat None like vid to remove hierarchy of layout
thr_crd = (tidx, cute.repeat_like(None, tidfrgInputs[0][1]))
# slice for threads
###############################################################################
# Slice to local tile of thread
###############################################################################
# vid -> address
thrInputs = [t[thr_coord] for t in tidfrgInputs] # (V)
thrC = tidfrgC[thr_coord] # (V)
thrCrd = tidfrgCrd[thr_coord]
thrInputs = [t[thr_crd] for t in tidfrgInputs] # (V)
thrC = tidfrgC[thr_crd] # (V)
thrCrd = tidfrgCrd[thr_crd]
print(f"[DSL INFO] Sliced Tensors per thread:")
print("[DSL INFO] Sliced Tensors per thread:")
for i in cutlass.range_constexpr(len(thrInputs)):
print(f"[DSL INFO] thrInputs{i} = {thrInputs[i].type}")
print(f"[DSL INFO] thrC = {thrC.type}")
print(f"[DSL INFO] thrCrd = {thrCrd.type}")
# allocate fragments for gmem->rmem
frgInputs = [cute.make_fragment_like(t, t.element_type) for t in thrInputs]
frgC = cute.make_fragment_like(thrC, gC.element_type)
frgPred = cute.make_fragment(thrCrd.shape, cutlass.Boolean)
###############################################################################
# Compute predicate for out of boundary checks
###############################################################################
frgPred = cute.make_rmem_tensor(thrCrd.shape, cutlass.Boolean)
print(f"[DSL INFO] frgPred = {frgPred.type}")
for i in cutlass.range(cute.size(frgPred), unroll=1):
for i in cutlass.range_constexpr(cute.size(frgPred)):
frgPred[i] = cute.elem_less(thrCrd[i], shape)
# if tidx == 0 and bidx == 0:
# cute.print_tensor(frgPred)
##########################################################
# Move data to reg address space
# Load data and compute result
##########################################################
# declare the atoms which will be used later for memory copy
# Compile time validation: expect same element type for all input tensors so as to reuse the copy atom for load
assert all(t.element_type == inputs[0].element_type for t in inputs)
copy_atom_load = cute.make_copy_atom(
cute.nvgpu.CopyUniversalOp(),
inputs[0].element_type,
num_bits_per_copy=inputs[0].element_type.width,
)
copy_atom_store = cute.make_copy_atom(
cute.nvgpu.CopyUniversalOp(),
gC.element_type,
num_bits_per_copy=gC.element_type.width,
)
for thrInput, frgInput in zip(thrInputs, frgInputs):
cute.copy(copy_atom_load, thrInput, frgInput, pred=frgPred)
# Load data before use. The compiler will optimize the copy and load
# operations to convert some memory ld/st into register uses.
result = op(*[frgInput.load() for frgInput in frgInputs])
# Save the results back to registers. Here we reuse b's registers.
frgC.store(result)
# Copy the results back to c
cute.copy(copy_atom_store, frgC, thrC, pred=frgPred)
result = op(*[thrInput.load() for thrInput in thrInputs])
thrC.store(result)
@cute.jit
def elementwise_apply(
op: cutlass.Constexpr,
a: cute.Tensor,
b: cute.Tensor,
result: cute.Tensor,
stream: cuda.CUstream,
op: cutlass.Constexpr, inputs, result: cute.Tensor, stream: cuda.CUstream
):
"""CUDA kernel applying binary operator on each element of two n-D input tensors in
CuTe Python and store to result tensor.
@@ -232,51 +213,71 @@ def elementwise_apply(
# Opt-3: SOL with 2D thread tile
# * mA layout: (4096, 4096):(4096, 1)
# * TV layout map to (16, 128) logical tile
# * TV layout map to (64, 256) logical tile
# * tidx maps to mode-1 and input layout is contiguous on mode-1 for coalesced load-store
thr_layout = cute.make_layout((4, 32), stride=(32, 1))
val_layout = cute.make_layout((4, 4), stride=(4, 1))
# Use 128bit(16B) load as canonicalized form of val_layout then recast to target element-type
coalesced_ldst_bytes = 16
# Compile time validation: expect same element type for all input tensors
assert all(t.element_type == inputs[0].element_type for t in inputs)
dtype = inputs[0].element_type
thr_layout = cute.make_ordered_layout((4, 64), order=(1, 0))
val_layout = cute.make_ordered_layout((16, coalesced_ldst_bytes), order=(1, 0))
val_layout = cute.recast_layout(dtype.width, 8, val_layout)
tiler_mn, tv_layout = cute.make_layout_tv(thr_layout, val_layout)
print(f"[DSL INFO] Input Tensors:")
print(f"[DSL INFO] a = {a.type}")
print(f"[DSL INFO] b = {b.type}")
print(f"[DSL INFO] result = {result.type}")
print("[DSL INFO] Input Tensors:")
for i, t in enumerate(inputs):
print(f"[DSL INFO] inputs{i} = {t}")
print(f"[DSL INFO] result = {result}")
print(f"[DSL INFO] Tiling Parameters:")
print("[DSL INFO] Tiling Parameters:")
print(f"[DSL INFO] tiler_mn = {tiler_mn} per thread block")
print(f"[DSL INFO] tv_layout = {tv_layout}")
gA = cute.zipped_divide(a, tiler_mn) # ((TileM, TileN), (RestM, RestN))
gB = cute.zipped_divide(b, tiler_mn) # ((TileM, TileN), (RestM, RestN))
gC = cute.zipped_divide(result, tiler_mn) # ((TileM, TileN), (RestM, RestN))
print("[DSL INFO] Tiled Tensors:")
mInputs = [cute.zipped_divide(input, tiler_mn) for input in inputs]
# ((TileM, TileN), (RestM, RestN))
mC = cute.zipped_divide(result, tiler_mn)
print(f"[DSL INFO] Tiled Tensors:")
print(f"[DSL INFO] gA = {gA.type}")
print(f"[DSL INFO] gB = {gB.type}")
print(f"[DSL INFO] gC = {gC.type}")
# (RestM, RestN) -> (RestN, RestM)
remap_block = cute.make_ordered_layout(
cute.select(mInputs[0].shape[1], mode=[1, 0]), order=(1, 0)
)
for i, t in enumerate(mInputs):
print(f"[DSL INFO] gInputs{i} = {mInputs[i]}")
mInputs[i] = cute.composition(t, (None, remap_block))
print(f"[DSL INFO] gInputs{i} (remapped) = {mInputs[i]}")
mC = cute.composition(mC, (None, remap_block))
print(f"[DSL INFO] gC = {mC}")
idC = cute.make_identity_tensor(result.shape)
cC = cute.zipped_divide(idC, tiler=tiler_mn)
print(f"[DSL INFO] coord tensor = {cC.type}")
print(f"[DSL INFO] coord tensor = {cC}")
# Launch the kernel asynchronously
# Async token(s) can also be specified as dependencies
elementwise_apply_kernel(
op,
[gA, gB], # Group input tensors into a list as a single argument
gC,
cC,
result.shape,
tv_layout,
).launch(
grid=[cute.size(gC, mode=[1]), 1, 1],
# Group input tensors into a list as a single argument
elementwise_apply_kernel(op, mInputs, mC, cC, result.shape, tv_layout).launch(
# Compute production at each mode of mC.shape[1] to get multi-dimensional grid size
grid=cute.product_each(mC.shape[1]),
block=[cute.size(tv_layout, mode=[0]), 1, 1],
stream=stream,
)
def run_elementwise_apply_and_verify(
@cutlass.dsl_user_op
def leaky_relu(x, alpha, *, loc=None, ip=None):
return cute.where(x > 0, x, alpha * x, loc=loc, ip=ip)
def leaky_relu_ref(x, alpha):
return torch.where(x > 0, x, alpha * x)
def run_and_verify(
op,
M,
N,
@@ -287,14 +288,23 @@ def run_elementwise_apply_and_verify(
iterations=100,
):
if not torch.cuda.is_available():
raise RuntimeError(f"Ampere GPU is required to run this example!")
raise RuntimeError("NVIDIA GPU is required to run this example!")
if op == "leaky_relu":
op = partial(leaky_relu, alpha=0.01)
ref_op = partial(leaky_relu_ref, alpha=0.01)
num_inputs = 1
else:
op = getattr(operator, op)
ref_op = op
num_inputs = 2
# Create non default CUDA stream from PyTorch
torch_stream = torch.cuda.Stream()
# Get the raw stream pointer as a CUstream
current_stream = cuda.CUstream(torch_stream.cuda_stream)
print(f"\nRunning Elementwise Apply test with:")
print("\nRunning Elementwise Apply test with:")
print(f"Tensor dimensions: [{M}, {N}]")
print(f"Input and Output Data type: {dtype}")
print(f"Warmup iterations: {warmup_iterations}")
@@ -303,85 +313,78 @@ def run_elementwise_apply_and_verify(
torch_dtype = cutlass_torch.dtype(dtype)
# Allocate tensors with random values.
a = torch.randn(M, N, device=torch.device("cuda"), dtype=torch_dtype)
b = torch.randn(M, N, device=torch.device("cuda"), dtype=torch_dtype)
c = torch.zeros_like(a)
inputs = [
torch.randn(M, N, device=torch.device("cuda"), dtype=torch_dtype)
for _ in range(num_inputs)
]
c = torch.zeros_like(inputs[0])
print(f"Input tensor shapes:")
print(f"a: {a.shape}, dtype: {a.dtype}")
print(f"b: {b.shape}, dtype: {b.dtype}")
print("Input tensor shapes:")
for i in range(num_inputs):
print(f"inputs[{i}]: {inputs[i].shape}, dtype: {inputs[i].dtype}")
print(f"c: {c.shape}, dtype: {c.dtype}\n")
epsilon = 1.2
if op in (operator.truediv, operator.floordiv):
b = torch.where(b == 0, torch.tensor(epsilon), b)
inputs[1] = torch.where(inputs[1] == 0, torch.tensor(epsilon), inputs[1])
print("Executing elementwise apply kernel...")
inputs_ = [from_dlpack(t, assumed_align=16) for t in inputs]
c_ = from_dlpack(c, assumed_align=16).mark_layout_dynamic()
print("Compiling kernel with cute.compile ...")
start_time = time.time()
compiled_fn = cute.compile[cute.GenerateLineInfo(True)](
elementwise_apply, op, inputs_, c_, current_stream
)
compilation_time = time.time() - start_time
print(f"Compilation time: {compilation_time:.4f} seconds")
if not skip_ref_check:
elementwise_apply(
op,
from_dlpack(a),
from_dlpack(b),
from_dlpack(c).mark_layout_dynamic(),
current_stream,
)
print("Executing elementwise apply kernel...")
compiled_fn(inputs_, c_, current_stream)
print("Verifying results...")
torch.testing.assert_close(op(a, b), c)
torch.testing.assert_close(ref_op(*inputs), c)
print("Results verified successfully!")
print(f"First few elements of result: \n{c[:3, :3]}")
if not benchmark:
return
compiled_func = cute.compile(
elementwise_apply,
op,
from_dlpack(a),
from_dlpack(b),
from_dlpack(c).mark_layout_dynamic(),
current_stream,
)
# When compiled we inlined op in the kernel, so we do not pass it when benchmarking
print("Benchmarking elementwise apply kernel...")
avg_time_us = testing.benchmark(
compiled_func,
kernel_arguments=testing.JitArguments(
from_dlpack(a),
from_dlpack(b),
from_dlpack(c).mark_layout_dynamic(),
current_stream,
),
compiled_fn,
kernel_arguments=testing.JitArguments(inputs_, c_, current_stream),
warmup_iterations=warmup_iterations,
iterations=iterations,
use_cuda_graphs=True,
stream=current_stream,
)
avg_time = avg_time_us / 1e3
num_elements = sum(input.numel() for input in inputs) + c.numel()
# Print execution results
print(f"Kernel execution time: {avg_time:.4f} ms")
print(f"Kernel execution time: {avg_time_us / 1e3:.4f} ms")
print(
f"Achieved memory throughput: {(3 * a.numel() * dtype.width // 8) / (avg_time / 1000) / 1e9:.2f} GB/s"
f"Achieved memory throughput: {(num_elements * dtype.width // 8) / (avg_time_us * 1000):.2f} GB/s"
)
print(f"First few elements of result: \n{c[:3, :3]}")
if __name__ == "__main__":
parser = argparse.ArgumentParser(
description="example of elementwise apply to demonstrate building elementwise kernels"
description="Demonstration of building customizable elementwise CUDA kernels using the CuTe DSL"
)
parser.add_argument("--M", default=128, type=int)
parser.add_argument("--N", default=128, type=int)
parser.add_argument("--M", default=4096, type=int)
parser.add_argument("--N", default=4096, type=int)
parser.add_argument("--op", default="add", type=str)
parser.add_argument("--warmup_iterations", default=2, type=int)
parser.add_argument("--iterations", default=100, type=int)
parser.add_argument("--skip_ref_check", action="store_true")
parser.add_argument("--benchmark", action="store_true")
args = parser.parse_args()
run_elementwise_apply_and_verify(
getattr(operator, args.op),
run_and_verify(
args.op,
args.M,
args.N,
dtype=cutlass.Float32,