submission 484166
Arseni Ivanov · python · License unknown
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grouped_gemm.py
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Compatibility
measured onNVIDIA B200
declared hardwareNVIDIA B200
architecturessm_100
dtypesfp8_e4m3, nvfp4
Benchmark evidence
1 measurement across 1 GPU, fastest first.
Operation / workload
Hardware
Latency
Rank
Observed
Reported · How evidence levels are derived →
Source and license
sourceavailable
revision digestsha256:85458d043b7f21d71184395b8a8fffbb299086d6fa873747f8e8d599539e4970
license declaredunknown
license concludedunknown
authorsArseni Ivanov
imported2026-08-15
Techniques
Extracted from the mirrored source by pattern, never inferred. Each row cites its line.
fused-epilogue
- Computing epilogue subtilembarrier
self.epilog_sync_barrier = pipeline.NamedBarrier(persistent-kernel
warp-specialized persistent kernel.shared-memory
self.smem_capacity = utils.get_smem_capacity_in_bytes("sm_100")tcgen05
tcgen05.CtaGroup.TWO if self.use_2cta_instrs else tcgen05.CtaGroup.ONEwarp-specialization
ab_pipeline_producer_group = pipeline.CooperativeGroup(pipeline.Agent.Thread)Kernel source
grouped_gemm.py2296 lines
#!POPCORN leaderboard nvfp4_group_gemm
#!POPCORN gpu B200
import cutlass
import cutlass.cute as cute
import cutlass.utils as utils
import cutlass.pipeline as pipeline
from cutlass.cute.nvgpu import cpasync, tcgen05
import cutlass.utils.blackwell_helpers as sm100_utils
import cutlass.utils.blockscaled_layout as blockscaled_utils
from cutlass.cute.runtime import make_ptr
from task import input_t, output_t
from typing import List, Type, Tuple, Union
from inspect import isclass
import torch
from cutlass.pipeline import pipeline_init_arrive, pipeline_init_wait
ab_dtype = cutlass.Float4E2M1FN
sf_dtype = cutlass.Float8E4M3FN
c_dtype = cutlass.Float16
sf_vec_size = 16
_TMA_CACHE_EVICT_NORMAL = 0x1000000000000000
_TMA_CACHE_EVICT_FIRST = 0x12F0000000000000
_TMA_CACHE_EVICT_LAST = 0x14F0000000000000
config_map = {
(4096, 7168): ((128, 128), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_FIRST),
(7168, 2048): ((128, 256), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_LAST),
(3072, 4096): ((128, 128), (1, 4), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_LAST),
(4096, 1536): ((128, 128), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_LAST),
}
class Sm100GroupedBlockScaledGemmKernel:
"""This example demonstrates an implementation of grouped blockscaled GEMM using a TMA plus Blackwell SM100 TensorCore
warp-specialized persistent kernel.
:param sf_vec_size: Scalefactor vector size.
:type sf_vec_size: int
:param mma_tiler_mn: Shape of the Matrix Multiply-Accumulate (MMA) tile (M,N)
:type mma_tiler_mn: Tuple[int, int]
:param cluster_shape_mn: Cluster dimensions (M,N) for parallel processing
:type cluster_shape_mn: Tuple[int, int]
:note: In current version, A and B tensors must have the same data type
- i.e., Float8E4M3FN for A and Float8E5M2 for B is not supported
:note: Supported combinations of A/B data types, SF data typs and SF vector size:
- MXF8: A/B: Float8E5M2/Float8E4M3FN + SF: Float8E8M0FNU + sf_vec_size: 32
- MXF4: A/B: Float4E2M1FN + SF: Float8E8M0FNU + sf_vec_size: 32
- NVF4: A/B: Float4E2M1FN + SF: Float8E8M0FNU/Float8E4M3FN + sf_vec_size: 16
:note: Supported accumulator data types:
- Float32
:note: Supported C data types:
- Float32
- Float16/BFloat16
- Float8E4M3FN/Float8E5M2
:note: Constraints:
- MMA tiler M must be 128 or 256 (use_2cta_instrs)
- MMA tiler N must be 128/256
- Cluster shape M must be multiple of 2 if Mma tiler M is 256
- Cluster shape M/N must be positive and power of 2, total cluster size <= 16
- Cluster shape M/N must be <= 4 for scale factor multicasts due to limited size of scale factors
"""
def __init__(
self,
sf_vec_size: int,
mma_tiler_mn: Tuple[int, int],
cluster_shape_mn: Tuple[int, int],
):
"""Initializes the configuration for a Blackwell grouped blockscaled GEMM kernel.
Besides configurations for dense persistent blockscaled GEMM, there is an extra config specific to grouped blockscaled GEMM:
:param sf_vec_size: Scalefactor vector size.
:type sf_vec_size: int
:param mma_tiler_mn: tuple (M, N) shape of the MMA instruction.
:type mma_tiler_mn: tuple[int, int]
:param cluster_shape_mn: tuple (ClusterM, ClusterN) shape of the cluster.
:type cluster_shape_mn: tuple[int, int]
"""
self.prefetch = True
self.cache_policy = _TMA_CACHE_EVICT_LAST
self.acc_dtype = cutlass.Float32
self.sf_vec_size = sf_vec_size
self.use_2cta_instrs = mma_tiler_mn[0] == 256
self.cluster_shape_mn = cluster_shape_mn
# K dimension is deferred in _setup_attributes
self.mma_tiler = (*mma_tiler_mn, 1)
self.cta_group = (
tcgen05.CtaGroup.TWO if self.use_2cta_instrs else tcgen05.CtaGroup.ONE
)
self.tensormap_update_mode = utils.TensorMapUpdateMode.SMEM
self.occupancy = 1
# Set specialized warp ids
self.epilog_warp_id = (
0,
1,
2,
3,
)
self.mma_warp_id = 4
self.tma_warp_id = 5
self.threads_per_cta = 32 * len(
(self.mma_warp_id, self.tma_warp_id, *self.epilog_warp_id)
)
# Set barrier for epilogue sync and tmem ptr sync
self.epilog_sync_barrier = pipeline.NamedBarrier(
barrier_id=1,
num_threads=32 * len(self.epilog_warp_id),
)
self.tmem_alloc_barrier = pipeline.NamedBarrier(
barrier_id=2,
num_threads=32 * len((self.mma_warp_id, *self.epilog_warp_id)),
)
# Barrier used by MMA/TMA warps to signal A/B tensormap initialization completion
self.tensormap_ab_init_barrier = pipeline.NamedBarrier(
barrier_id=3,
num_threads=64,
)
self.smem_capacity = utils.get_smem_capacity_in_bytes("sm_100")
SM100_TMEM_CAPACITY_COLUMNS = 512
self.num_tmem_alloc_cols = SM100_TMEM_CAPACITY_COLUMNS
# Set up configurations that dependent on gemm inputs.
def _setup_attributes(self):
"""Set up configurations that are dependent on GEMM inputs
This method configures various attributes based on the input tensor properties
(data types, leading dimensions) and kernel settings:
- Configuring tiled MMA
- Computing MMA/cluster/tile shapes
- Computing cluster layout
- Computing multicast CTAs for A/B/SFA/SFB
- Computing epilogue subtile
- Setting up A/B/SFA/SFB/C stage counts in shared memory
- Computing A/B/SFA/SFB/C shared memory layout
- Checking reserved smem bytes size capacity for mbar, tensor memory management and tensormap updates utilization
"""
# Compute mma instruction shapes
# (MMA_Tile_Shape_M, MMA_Tile_Shape_N, MMA_Inst_Shape_K)
self.mma_inst_shape_mn = (
self.mma_tiler[0],
self.mma_tiler[1],
)
# (CTA_Tile_Shape_M, Round_Up(MMA_Tile_Shape_N, 128), MMA_Inst_Shape_K)
self.mma_inst_shape_mn_sfb = (
self.mma_inst_shape_mn[0] // (2 if self.use_2cta_instrs else 1),
cute.round_up(self.mma_inst_shape_mn[1], 128),
)
tiled_mma = sm100_utils.make_blockscaled_trivial_tiled_mma(
self.a_dtype,
self.a_major_mode,
self.b_major_mode,
self.sf_dtype,
self.sf_vec_size,
self.cta_group,
self.mma_inst_shape_mn,
)
tiled_mma_sfb = sm100_utils.make_blockscaled_trivial_tiled_mma(
self.a_dtype,
self.a_major_mode,
self.b_major_mode,
self.sf_dtype,
self.sf_vec_size,
cute.nvgpu.tcgen05.CtaGroup.ONE,
self.mma_inst_shape_mn_sfb,
)
# Compute mma/cluster/tile shapes
mma_inst_shape_k = cute.size(tiled_mma.shape_mnk, mode=[2])
mma_inst_tile_k = 4
self.mma_tiler = (
self.mma_inst_shape_mn[0],
self.mma_inst_shape_mn[1],
mma_inst_shape_k * mma_inst_tile_k,
)
self.mma_tiler_sfb = (
self.mma_inst_shape_mn_sfb[0],
self.mma_inst_shape_mn_sfb[1],
mma_inst_shape_k * mma_inst_tile_k,
)
self.cta_tile_shape_mnk = (
self.mma_tiler[0] // cute.size(tiled_mma.thr_id.shape),
self.mma_tiler[1],
self.mma_tiler[2],
)
self.cluster_tile_shape_mnk = tuple(
x * y for x, y in zip(self.cta_tile_shape_mnk, (*self.cluster_shape_mn, 1))
)
# Compute cluster layout
self.cluster_layout_vmnk = cute.tiled_divide(
cute.make_layout((*self.cluster_shape_mn, 1)),
(tiled_mma.thr_id.shape,),
)
self.cluster_layout_sfb_vmnk = cute.tiled_divide(
cute.make_layout((*self.cluster_shape_mn, 1)),
(tiled_mma_sfb.thr_id.shape,),
)
# Compute number of multicast CTAs for A/B
self.num_mcast_ctas_a = cute.size(self.cluster_layout_vmnk.shape[2])
self.num_mcast_ctas_b = cute.size(self.cluster_layout_vmnk.shape[1])
self.num_mcast_ctas_sfb = cute.size(self.cluster_layout_sfb_vmnk.shape[1])
self.is_a_mcast = self.num_mcast_ctas_a > 1
self.is_b_mcast = self.num_mcast_ctas_b > 1
self.is_sfb_mcast = self.num_mcast_ctas_sfb > 1
# Compute epilogue subtile
self.epi_tile = sm100_utils.compute_epilogue_tile_shape(
self.cta_tile_shape_mnk,
self.use_2cta_instrs,
self.c_layout,
self.c_dtype,
)
# Setup A/B/C stage count in shared memory and ACC stage count in tensor memory
self.num_acc_stage, self.num_ab_stage, self.num_c_stage = self._compute_stages(
tiled_mma,
self.mma_tiler,
self.a_dtype,
self.b_dtype,
self.epi_tile,
self.c_dtype,
self.c_layout,
self.sf_dtype,
self.sf_vec_size,
self.smem_capacity,
self.occupancy,
)
# Compute A/B/SFA/SFB/C shared memory layout
self.a_smem_layout_staged = sm100_utils.make_smem_layout_a(
tiled_mma,
self.mma_tiler,
self.a_dtype,
self.num_ab_stage,
)
self.b_smem_layout_staged = sm100_utils.make_smem_layout_b(
tiled_mma,
self.mma_tiler,
self.b_dtype,
self.num_ab_stage,
)
self.sfa_smem_layout_staged = blockscaled_utils.make_smem_layout_sfa(
tiled_mma,
self.mma_tiler,
self.sf_vec_size,
self.num_ab_stage,
)
self.sfb_smem_layout_staged = blockscaled_utils.make_smem_layout_sfb(
tiled_mma,
self.mma_tiler,
self.sf_vec_size,
self.num_ab_stage,
)
self.c_smem_layout_staged = sm100_utils.make_smem_layout_epi(
self.c_dtype,
self.c_layout,
self.epi_tile,
self.num_c_stage,
)
mbar_smem_bytes = self._get_mbar_smem_bytes(
num_acc_stage=self.num_acc_stage,
num_ab_stage=self.num_ab_stage,
num_c_stage=self.num_c_stage,
)
# Use utils.TensorMapUpdateMode.SMEM by default
tensormap_smem_bytes = (
Sm100GroupedBlockScaledGemmKernel.bytes_per_tensormap
* Sm100GroupedBlockScaledGemmKernel.num_tensormaps
)
if (
mbar_smem_bytes
+ tensormap_smem_bytes
+ Sm100GroupedBlockScaledGemmKernel.tensor_memory_management_bytes
> self.reserved_smem_bytes
):
raise ValueError(
f"smem consumption for mbar and tensormap {mbar_smem_bytes + tensormap_smem_bytes} exceeds the "
f"reserved smem bytes {self.reserved_smem_bytes}"
)
@cute.jit
def __call__(
self,
ptr_of_tensor_of_problem_sizes: cute.Pointer,
ptr_of_tensor_of_abc_ptrs: cute.Pointer,
ptr_of_tensor_of_sfasfb_ptrs: cute.Pointer,
ptr_of_tensor_of_tensormap: cute.Pointer,
total_num_clusters: cutlass.Int32,
num_groups: cutlass.Constexpr[int],
max_active_clusters: cutlass.Constexpr[int],
):
"""Execute the GEMM operation in steps:
- Setup static attributes before smem/grid/tma computation
- Setup TMA load/store atoms and tensors
- Compute grid size with regard to hardware constraints
- Define shared storage for kernel
- Launch the kernel synchronously
For grouped GEMM, tensor shapes, tensor strides, and tensor address are all provided
by different tensors in global memory. The "initial" tensors only carry data type and
majorness information.
:param initial_a: Initial tensor A, used for data type and majorness information.
:type initial_a: cute.Tensor
:param initial_b: Initial tensor B, used for data type and majorness information.
:type initial_b: cute.Tensor
:param initial_c: Initial tensor C, used for data type and majorness information.
:type initial_c: cute.Tensor
:param initial_sfa: Initial tensor SFA, used for data type and majorness information.
:type initial_sfa: cute.Tensor
:param initial_sfb: Initial tensor SFB, used for data type and majorness information.
:type initial_sfb: cute.Tensor
:param group_count: The number of GEMM groups.
:type group_count: cutlass.Constexpr[int]
:param problem_shape_mnkl: Tensor containing the (M, N, K, L) shape for each group.
:type problem_shape_mnkl: cute.Tensor
:param strides_abc: Tensor containing the strides for A, B, and C for each group.
:type strides_abc: cute.Tensor
:param tensor_address_abc: Tensor containing the base addresses for A, B, and C for each group.
:type tensor_address_abc: cute.Tensor
:param tensor_address_sfasfb: Tensor containing the base addresses for SFA and SFB for each group.
:type tensor_address_sfasfb: cute.Tensor
:param total_num_clusters: Total number of clusters needed for all groups.
:type total_num_clusters: cutlass.Constexpr[int]
:param tensormap_cute_tensor: Tensor for storing tensormaps.
:type tensormap_cute_tensor: cute.Tensor
:param max_active_clusters: Maximum number of active clusters.
:type max_active_clusters: cutlass.Constexpr[int]
:raises TypeError: If A and B data types do not match.
"""
tensor_of_abc_ptrs = cute.make_tensor(
ptr_of_tensor_of_abc_ptrs, cute.make_layout((num_groups, 3), stride=(3, 1))
)
tensor_of_sfasfb_ptrs = cute.make_tensor(
ptr_of_tensor_of_sfasfb_ptrs, cute.make_layout((num_groups, 2), stride=(2, 1))
)
tensor_of_problem_sizes = cute.make_tensor(
ptr_of_tensor_of_problem_sizes, cute.make_layout((num_groups, 4), stride=(4, 1))
)
tensor_of_tensormap = cute.make_tensor(
ptr_of_tensor_of_tensormap, cute.make_layout((total_num_clusters, self.num_tensormaps, 16), stride=(16*self.num_tensormaps, 16, 1))
)
# Use fake shape for initial Tma descriptor and atom setup
# The real Tma desc and atom will be updated during kernel execution.
min_a_shape = (cutlass.Int32(64), cutlass.Int32(64), cutlass.Int32(64), cutlass.Int32(1))
min_b_shape = (cutlass.Int32(64), cutlass.Int32(64), cutlass.Int32(64), cutlass.Int32(1))
min_c_shape = (cutlass.Int32(64), cutlass.Int32(64), cutlass.Int32(64), cutlass.Int32(1))
initial_a = cute.make_tensor(
cute.make_ptr(ab_dtype, 0, cute.AddressSpace.gmem, assumed_align=16,),
cute.make_layout(
(min_a_shape[0], cute.assume(min_a_shape[2], 32), min_a_shape[3]),
stride=(
cute.assume(min_a_shape[2], 32),
1,
cute.assume(min_a_shape[0] * min_a_shape[2], 32),
),
),
)
initial_b = cute.make_tensor(
cute.make_ptr(ab_dtype, 0, cute.AddressSpace.gmem, assumed_align=16,),
cute.make_layout(
(min_b_shape[1], cute.assume(min_b_shape[2], 32), min_b_shape[3]),
stride=(
cute.assume(min_b_shape[2], 32),
1,
cute.assume(min_b_shape[1] * min_b_shape[2], 32),
),
),
)
initial_c = cute.make_tensor(
cute.make_ptr(c_dtype, 0, cute.AddressSpace.gmem, assumed_align=16),
cute.make_layout(
(min_c_shape[0], min_c_shape[1], min_c_shape[3]),
stride=(
cute.assume(min_c_shape[1], 32),
1,
cute.assume(min_c_shape[0] * min_c_shape[1], 32),
),
),
)
# Setup sfa/sfb tensor by filling A/B tensor to scale factor atom layout
# ((Atom_M, Rest_M),(Atom_K, Rest_K),RestL)
sfa_layout = blockscaled_utils.tile_atom_to_shape_SF(
initial_a.shape, sf_vec_size
)
# ((Atom_N, Rest_N),(Atom_K, Rest_K),RestL)
sfb_layout = blockscaled_utils.tile_atom_to_shape_SF(
initial_b.shape, sf_vec_size
)
# Create initial SFA and SFB tensors with null pointers
initial_sfa = cute.make_tensor(
cute.make_ptr(sf_dtype, 0, cute.AddressSpace.gmem, assumed_align=16), sfa_layout
)
initial_sfb = cute.make_tensor(
cute.make_ptr(sf_dtype, 0, cute.AddressSpace.gmem, assumed_align=16), sfb_layout
)
self.a_dtype = initial_a.element_type
self.b_dtype = initial_b.element_type
self.sf_dtype = initial_sfa.element_type
self.c_dtype = initial_c.element_type
self.a_major_mode = utils.LayoutEnum.from_tensor(initial_a).mma_major_mode()
self.b_major_mode = utils.LayoutEnum.from_tensor(initial_b).mma_major_mode()
self.c_layout = utils.LayoutEnum.from_tensor(initial_c)
if cutlass.const_expr(self.a_dtype != self.b_dtype):
raise TypeError(f"Type mismatch: {self.a_dtype} != {self.b_dtype}")
# Setup attributes that dependent on gemm inputs
self._setup_attributes()
# Setup sfa/sfb tensor by filling A/B tensor to scale factor atom layout
# ((Atom_M, Rest_M),(Atom_K, Rest_K),RestL)
sfa_layout = blockscaled_utils.tile_atom_to_shape_SF(
initial_a.shape, self.sf_vec_size
)
initial_sfa = cute.make_tensor(initial_sfa.iterator, sfa_layout)
# ((Atom_N, Rest_N),(Atom_K, Rest_K),RestL)
sfb_layout = blockscaled_utils.tile_atom_to_shape_SF(
initial_b.shape, self.sf_vec_size
)
initial_sfb = cute.make_tensor(initial_sfb.iterator, sfb_layout)
tiled_mma = sm100_utils.make_blockscaled_trivial_tiled_mma(
self.a_dtype,
self.a_major_mode,
self.b_major_mode,
self.sf_dtype,
self.sf_vec_size,
self.cta_group,
self.mma_inst_shape_mn,
)
tiled_mma_sfb = sm100_utils.make_blockscaled_trivial_tiled_mma(
self.a_dtype,
self.a_major_mode,
self.b_major_mode,
self.sf_dtype,
self.sf_vec_size,
cute.nvgpu.tcgen05.CtaGroup.ONE,
self.mma_inst_shape_mn_sfb,
)
atom_thr_size = cute.size(tiled_mma.thr_id.shape)
# Setup TMA load for A
a_op = sm100_utils.cluster_shape_to_tma_atom_A(
self.cluster_shape_mn, tiled_mma.thr_id
)
a_smem_layout = cute.slice_(self.a_smem_layout_staged, (None, None, None, 0))
tma_atom_a, tma_tensor_a = cute.nvgpu.make_tiled_tma_atom_A(
a_op,
initial_a,
a_smem_layout,
self.mma_tiler,
tiled_mma,
self.cluster_layout_vmnk.shape,
)
# Setup TMA load for B
b_op = sm100_utils.cluster_shape_to_tma_atom_B(
self.cluster_shape_mn, tiled_mma.thr_id
)
b_smem_layout = cute.slice_(self.b_smem_layout_staged, (None, None, None, 0))
tma_atom_b, tma_tensor_b = cute.nvgpu.make_tiled_tma_atom_B(
b_op,
initial_b,
b_smem_layout,
self.mma_tiler,
tiled_mma,
self.cluster_layout_vmnk.shape,
)
# Setup TMA load for SFA
sfa_op = sm100_utils.cluster_shape_to_tma_atom_A(
self.cluster_shape_mn, tiled_mma.thr_id
)
sfa_smem_layout = cute.slice_(
self.sfa_smem_layout_staged, (None, None, None, 0)
)
tma_atom_sfa, tma_tensor_sfa = cute.nvgpu.make_tiled_tma_atom_A(
sfa_op,
initial_sfa,
sfa_smem_layout,
self.mma_tiler,
tiled_mma,
self.cluster_layout_vmnk.shape,
internal_type=cutlass.Int16,
)
# Setup TMA load for SFB
sfb_op = sm100_utils.cluster_shape_to_tma_atom_SFB(
self.cluster_shape_mn, tiled_mma.thr_id
)
sfb_smem_layout = cute.slice_(
self.sfb_smem_layout_staged, (None, None, None, 0)
)
tma_atom_sfb, tma_tensor_sfb = cute.nvgpu.make_tiled_tma_atom_B(
sfb_op,
initial_sfb,
sfb_smem_layout,
self.mma_tiler_sfb,
tiled_mma_sfb,
self.cluster_layout_sfb_vmnk.shape,
internal_type=cutlass.Int16,
)
a_copy_size = cute.size_in_bytes(self.a_dtype, a_smem_layout)
b_copy_size = cute.size_in_bytes(self.b_dtype, b_smem_layout)
sfa_copy_size = cute.size_in_bytes(self.sf_dtype, sfa_smem_layout)
sfb_copy_size = cute.size_in_bytes(self.sf_dtype, sfb_smem_layout)
self.num_tma_load_bytes = (
a_copy_size + b_copy_size + sfa_copy_size + sfb_copy_size
) * atom_thr_size
# Setup TMA store for C
epi_smem_layout = cute.slice_(self.c_smem_layout_staged, (None, None, 0))
tma_atom_c, tma_tensor_c = cpasync.make_tiled_tma_atom(
cpasync.CopyBulkTensorTileS2GOp(),
initial_c,
epi_smem_layout,
self.epi_tile,
)
# Compute grid size
self.tile_sched_params, grid = self._compute_grid(
total_num_clusters, self.cluster_shape_mn, max_active_clusters
)
self.buffer_align_bytes = 1024
self.size_tensormap_in_i64 = (
Sm100GroupedBlockScaledGemmKernel.num_tensormaps
* Sm100GroupedBlockScaledGemmKernel.bytes_per_tensormap
// 8
)
# Define shared storage for kernel
@cute.struct
class SharedStorage:
tensormap_buffer: cute.struct.MemRange[
cutlass.Int64, self.size_tensormap_in_i64
]
ab_full_mbar_ptr: cute.struct.MemRange[cutlass.Int64, self.num_ab_stage]
ab_empty_mbar_ptr: cute.struct.MemRange[cutlass.Int64, self.num_ab_stage]
acc_full_mbar_ptr: cute.struct.MemRange[cutlass.Int64, self.num_acc_stage]
acc_empty_mbar_ptr: cute.struct.MemRange[cutlass.Int64, self.num_acc_stage]
tmem_dealloc_mbar_ptr: cutlass.Int64
tmem_holding_buf: cutlass.Int32
# (EPI_TILE_M, EPI_TILE_N, STAGE)
sC: cute.struct.Align[
cute.struct.MemRange[
self.c_dtype,
cute.cosize(self.c_smem_layout_staged.outer),
],
self.buffer_align_bytes,
]
# (MMA, MMA_M, MMA_K, STAGE)
sA: cute.struct.Align[
cute.struct.MemRange[
self.a_dtype, cute.cosize(self.a_smem_layout_staged.outer)
],
self.buffer_align_bytes,
]
# (MMA, MMA_N, MMA_K, STAGE)
sB: cute.struct.Align[
cute.struct.MemRange[
self.b_dtype, cute.cosize(self.b_smem_layout_staged.outer)
],
self.buffer_align_bytes,
]
# (MMA, MMA_M, MMA_K, STAGE)
sSFA: cute.struct.Align[
cute.struct.MemRange[
self.sf_dtype, cute.cosize(self.sfa_smem_layout_staged)
],
self.buffer_align_bytes,
]
# (MMA, MMA_N, MMA_K, STAGE)
sSFB: cute.struct.Align[
cute.struct.MemRange[
self.sf_dtype, cute.cosize(self.sfb_smem_layout_staged)
],
self.buffer_align_bytes,
]
self.shared_storage = SharedStorage
# Launch the kernel synchronously
self.kernel(
tiled_mma,
tiled_mma_sfb,
tma_atom_a,
tma_tensor_a,
tma_atom_b,
tma_tensor_b,
tma_atom_sfa,
tma_tensor_sfa,
tma_atom_sfb,
tma_tensor_sfb,
tma_atom_c,
tma_tensor_c,
self.cluster_layout_vmnk,
self.cluster_layout_sfb_vmnk,
self.a_smem_layout_staged,
self.b_smem_layout_staged,
self.sfa_smem_layout_staged,
self.sfb_smem_layout_staged,
self.c_smem_layout_staged,
self.epi_tile,
self.tile_sched_params,
num_groups,
tensor_of_problem_sizes,
tensor_of_abc_ptrs,
tensor_of_sfasfb_ptrs,
tensor_of_tensormap,
).launch(
grid=grid,
block=[self.threads_per_cta, 1, 1],
cluster=(*self.cluster_shape_mn, 1),
smem=self.shared_storage.size_in_bytes(),
min_blocks_per_mp=1,
)
return
# GPU device kernel
@cute.kernel
def kernel(
self,
tiled_mma: cute.TiledMma,
tiled_mma_sfb: cute.TiledMma,
tma_atom_a: cute.CopyAtom,
mA_mkl: cute.Tensor,
tma_atom_b: cute.CopyAtom,
mB_nkl: cute.Tensor,
tma_atom_sfa: cute.CopyAtom,
mSFA_mkl: cute.Tensor,
tma_atom_sfb: cute.CopyAtom,
mSFB_nkl: cute.Tensor,
tma_atom_c: cute.CopyAtom,
mC_mnl: cute.Tensor,
cluster_layout_vmnk: cute.Layout,
cluster_layout_sfb_vmnk: cute.Layout,
a_smem_layout_staged: cute.ComposedLayout,
b_smem_layout_staged: cute.ComposedLayout,
sfa_smem_layout_staged: cute.Layout,
sfb_smem_layout_staged: cute.Layout,
c_smem_layout_staged: Union[cute.Layout, cute.ComposedLayout],
epi_tile: cute.Tile,
tile_sched_params: utils.PersistentTileSchedulerParams,
group_count: cutlass.Int32,
problem_sizes_mnkl: cute.Tensor,
ptrs_abc: cute.Tensor,
ptrs_sfasfb: cute.Tensor,
tensormaps: cute.Tensor,
):
"""
GPU device kernel performing the grouped GEMM computation.
"""
warp_idx = cute.arch.warp_idx()
warp_idx = cute.arch.make_warp_uniform(warp_idx)
if warp_idx == self.tma_warp_id and self.prefetch:
cute.nvgpu.cpasync.prefetch_descriptor(tma_atom_a)
cute.nvgpu.cpasync.prefetch_descriptor(tma_atom_b)
cute.nvgpu.cpasync.prefetch_descriptor(tma_atom_sfa)
cute.nvgpu.cpasync.prefetch_descriptor(tma_atom_sfb)
cute.nvgpu.cpasync.prefetch_descriptor(tma_atom_c)
use_2cta_instrs = cute.size(tiled_mma.thr_id.shape) == 2
#
# Setup cta/thread coordinates
#
# Coords inside cluster
bidx, bidy, bidz = cute.arch.block_idx()
mma_tile_coord_v = bidx % cute.size(tiled_mma.thr_id.shape)
is_leader_cta = mma_tile_coord_v == 0
cta_rank_in_cluster = cute.arch.make_warp_uniform(
cute.arch.block_idx_in_cluster()
)
block_in_cluster_coord_vmnk = cluster_layout_vmnk.get_flat_coord(
cta_rank_in_cluster
)
block_in_cluster_coord_sfb_vmnk = cluster_layout_sfb_vmnk.get_flat_coord(
cta_rank_in_cluster
)
# coord inside cta
tidx, _, _ = cute.arch.thread_idx()
#
# Alloc and init: tensormap buffer, a+b full/empty, accumulator full/empty, tensor memory dealloc barrier
#
smem = utils.SmemAllocator()
storage = smem.allocate(self.shared_storage)
tensormap_smem_ptr = storage.tensormap_buffer.data_ptr()
tensormap_a_smem_ptr = tensormap_smem_ptr
tensormap_b_smem_ptr = (
tensormap_a_smem_ptr
+ Sm100GroupedBlockScaledGemmKernel.bytes_per_tensormap // 8
)
tensormap_sfa_smem_ptr = (
tensormap_b_smem_ptr
+ Sm100GroupedBlockScaledGemmKernel.bytes_per_tensormap // 8
)
tensormap_sfb_smem_ptr = (
tensormap_sfa_smem_ptr
+ Sm100GroupedBlockScaledGemmKernel.bytes_per_tensormap // 8
)
tensormap_c_smem_ptr = (
tensormap_sfb_smem_ptr
+ Sm100GroupedBlockScaledGemmKernel.bytes_per_tensormap // 8
)
# Initialize mainloop ab_pipeline (barrier) and states
ab_pipeline_producer_group = pipeline.CooperativeGroup(pipeline.Agent.Thread)
num_tma_producer = self.num_mcast_ctas_a + self.num_mcast_ctas_b - 1
ab_pipeline_consumer_group = pipeline.CooperativeGroup(
pipeline.Agent.Thread, num_tma_producer
)
ab_pipeline = pipeline.PipelineTmaUmma.create(
barrier_storage=storage.ab_full_mbar_ptr.data_ptr(),
num_stages=self.num_ab_stage,
producer_group=ab_pipeline_producer_group,
consumer_group=ab_pipeline_consumer_group,
tx_count=self.num_tma_load_bytes,
cta_layout_vmnk=cluster_layout_vmnk,
)
# Initialize acc_pipeline (barrier) and states
acc_pipeline_producer_group = pipeline.CooperativeGroup(pipeline.Agent.Thread)
num_acc_consumer_threads = len(self.epilog_warp_id) * (
2 if use_2cta_instrs else 1
)
acc_pipeline_consumer_group = pipeline.CooperativeGroup(
pipeline.Agent.Thread, num_acc_consumer_threads
)
acc_pipeline = pipeline.PipelineUmmaAsync.create(
barrier_storage=storage.acc_full_mbar_ptr.data_ptr(),
num_stages=self.num_acc_stage,
producer_group=acc_pipeline_producer_group,
consumer_group=acc_pipeline_consumer_group,
cta_layout_vmnk=cluster_layout_vmnk,
)
tmem = utils.TmemAllocator(
storage.tmem_holding_buf,
barrier_for_retrieve=self.tmem_alloc_barrier,
allocator_warp_id=self.epilog_warp_id[0],
is_two_cta=use_2cta_instrs,
two_cta_tmem_dealloc_mbar_ptr=storage.tmem_dealloc_mbar_ptr,
)
# Cluster arrive after barrier init
pipeline_init_arrive(cluster_shape_mn=self.cluster_shape_mn, is_relaxed=True)
#
# Setup smem tensor A/B/SFA/SFB/C
#
sC = storage.sC.get_tensor(
c_smem_layout_staged.outer, swizzle=c_smem_layout_staged.inner
)
# (MMA, MMA_M, MMA_K, STAGE)
sA = storage.sA.get_tensor(
a_smem_layout_staged.outer, swizzle=a_smem_layout_staged.inner
)
# (MMA, MMA_N, MMA_K, STAGE)
sB = storage.sB.get_tensor(
b_smem_layout_staged.outer, swizzle=b_smem_layout_staged.inner
)
# (MMA, MMA_M, MMA_K, STAGE)
sSFA = storage.sSFA.get_tensor(sfa_smem_layout_staged)
# (MMA, MMA_N, MMA_K, STAGE)
sSFB = storage.sSFB.get_tensor(sfb_smem_layout_staged)
#
# Compute multicast mask for A/B/SFA/SFB buffer full
#
a_full_mcast_mask = None
b_full_mcast_mask = None
sfa_full_mcast_mask = None
sfb_full_mcast_mask = None
if cutlass.const_expr(self.is_a_mcast or self.is_b_mcast or use_2cta_instrs):
a_full_mcast_mask = cpasync.create_tma_multicast_mask(
cluster_layout_vmnk, block_in_cluster_coord_vmnk, mcast_mode=2
)
b_full_mcast_mask = cpasync.create_tma_multicast_mask(
cluster_layout_vmnk, block_in_cluster_coord_vmnk, mcast_mode=1
)
sfa_full_mcast_mask = cpasync.create_tma_multicast_mask(
cluster_layout_vmnk, block_in_cluster_coord_vmnk, mcast_mode=2
)
sfb_full_mcast_mask = cpasync.create_tma_multicast_mask(
cluster_layout_sfb_vmnk, block_in_cluster_coord_sfb_vmnk, mcast_mode=1
)
#
# Local_tile partition global tensors
#
# (bM, bK, RestM, RestK, RestL)
gA_mkl = cute.local_tile(
mA_mkl, cute.slice_(self.mma_tiler, (None, 0, None)), (None, None, None)
)
# (bN, bK, RestN, RestK, RestL)
gB_nkl = cute.local_tile(
mB_nkl, cute.slice_(self.mma_tiler, (0, None, None)), (None, None, None)
)
# (bM, bK, RestM, RestK, RestL)
gSFA_mkl = cute.local_tile(
mSFA_mkl, cute.slice_(self.mma_tiler, (None, 0, None)), (None, None, None)
)
# (bN, bK, RestN, RestK, RestL)
gSFB_nkl = cute.local_tile(
mSFB_nkl, cute.slice_(self.mma_tiler, (0, None, None)), (None, None, None)
)
# (bM, bN, RestM, RestN, RestL)
gC_mnl = cute.local_tile(
mC_mnl, cute.slice_(self.mma_tiler, (None, None, 0)), (None, None, None)
)
#
# Partition global tensor for TiledMMA_A/B/C
#
thr_mma = tiled_mma.get_slice(mma_tile_coord_v)
thr_mma_sfb = tiled_mma_sfb.get_slice(mma_tile_coord_v)
# (MMA, MMA_M, MMA_K, RestM, RestK, RestL)
tCgA = thr_mma.partition_A(gA_mkl)
# (MMA, MMA_N, MMA_K, RestN, RestK, RestL)
tCgB = thr_mma.partition_B(gB_nkl)
# (MMA, MMA_M, MMA_K, RestM, RestK, RestL)
tCgSFA = thr_mma.partition_A(gSFA_mkl)
# (MMA, MMA_N, MMA_K, RestN, RestK, RestL)
tCgSFB = thr_mma_sfb.partition_B(gSFB_nkl)
# (MMA, MMA_M, MMA_N, RestM, RestN, RestL)
tCgC = thr_mma.partition_C(gC_mnl)
#
# Partition global/shared tensor for TMA load A/B
#
# TMA load A partition_S/D
a_cta_layout = cute.make_layout(
cute.slice_(cluster_layout_vmnk, (0, 0, None, 0)).shape
)
# ((atom_v, rest_v), STAGE)
# ((atom_v, rest_v), RestM, RestK, RestL)
tAsA, tAgA = cpasync.tma_partition(
tma_atom_a,
block_in_cluster_coord_vmnk[2],
a_cta_layout,
cute.group_modes(sA, 0, 3),
cute.group_modes(tCgA, 0, 3),
)
# TMA load B partition_S/D
b_cta_layout = cute.make_layout(
cute.slice_(cluster_layout_vmnk, (0, None, 0, 0)).shape
)
# ((atom_v, rest_v), STAGE)
# ((atom_v, rest_v), RestN, RestK, RestL)
tBsB, tBgB = cpasync.tma_partition(
tma_atom_b,
block_in_cluster_coord_vmnk[1],
b_cta_layout,
cute.group_modes(sB, 0, 3),
cute.group_modes(tCgB, 0, 3),
)
# TMA Load SFA partition_S/D
sfa_cta_layout = a_cta_layout
# ((atom_v, rest_v), STAGE)
# ((atom_v, rest_v), RestM, RestK, RestL)
tAsSFA, tAgSFA = cute.nvgpu.cpasync.tma_partition(
tma_atom_sfa,
block_in_cluster_coord_vmnk[2],
sfa_cta_layout,
cute.group_modes(sSFA, 0, 3),
cute.group_modes(tCgSFA, 0, 3),
)
tAsSFA = cute.filter_zeros(tAsSFA)
tAgSFA = cute.filter_zeros(tAgSFA)
# TMA Load SFB partition_S/D
sfb_cta_layout = cute.make_layout(
cute.slice_(cluster_layout_sfb_vmnk, (0, None, 0, 0)).shape
)
# ((atom_v, rest_v), STAGE)
# ((atom_v, rest_v), RestN, RestK, RestL)
tBsSFB, tBgSFB = cute.nvgpu.cpasync.tma_partition(
tma_atom_sfb,
block_in_cluster_coord_sfb_vmnk[1],
sfb_cta_layout,
cute.group_modes(sSFB, 0, 3),
cute.group_modes(tCgSFB, 0, 3),
)
tBsSFB = cute.filter_zeros(tBsSFB)
tBgSFB = cute.filter_zeros(tBgSFB)
#
# Partition shared/tensor memory tensor for TiledMMA_A/B/C
#
# (MMA, MMA_M, MMA_K, STAGE)
tCrA = tiled_mma.make_fragment_A(sA)
# (MMA, MMA_N, MMA_K, STAGE)
tCrB = tiled_mma.make_fragment_B(sB)
# (MMA, MMA_M, MMA_N)
acc_shape = tiled_mma.partition_shape_C(self.mma_tiler[:2])
# (MMA, MMA_M, MMA_N, STAGE)
tCtAcc_fake = tiled_mma.make_fragment_C(
cute.append(acc_shape, self.num_acc_stage)
)
#
# Cluster wait before tensor memory alloc
#
pipeline_init_wait(cluster_shape_mn=self.cluster_shape_mn)
#
# Get tensormap buffer address
#
grid_dim = cute.arch.grid_dim()
tensormap_workspace_idx = (
bidz * grid_dim[1] * grid_dim[0] + bidy * grid_dim[0] + bidx
)
tensormap_manager = utils.TensorMapManager(
utils.TensorMapUpdateMode.SMEM,
Sm100GroupedBlockScaledGemmKernel.bytes_per_tensormap,
)
tensormap_a_gmem_ptr = tensormap_manager.get_tensormap_ptr(
tensormaps[(tensormap_workspace_idx, 0, None)].iterator
)
tensormap_b_gmem_ptr = tensormap_manager.get_tensormap_ptr(
tensormaps[(tensormap_workspace_idx, 1, None)].iterator
)
tensormap_sfa_gmem_ptr = tensormap_manager.get_tensormap_ptr(
tensormaps[(tensormap_workspace_idx, 2, None)].iterator
)
tensormap_sfb_gmem_ptr = tensormap_manager.get_tensormap_ptr(
tensormaps[(tensormap_workspace_idx, 3, None)].iterator
)
tensormap_c_gmem_ptr = tensormap_manager.get_tensormap_ptr(
tensormaps[(tensormap_workspace_idx, 4, None)].iterator
)
#
# Specialized TMA load warp
#
if warp_idx == self.tma_warp_id:
#
# Persistent tile scheduling loop
#
tile_sched = utils.StaticPersistentTileScheduler.create(
tile_sched_params, cute.arch.block_idx(), grid_dim
)
# grouped gemm tile scheduler helper will compute the group index for the tile we're working on
group_gemm_ts_helper = utils.GroupedGemmTileSchedulerHelper(
group_count,
tile_sched_params,
self.cluster_tile_shape_mnk,
utils.create_initial_search_state(),
)
tensormap_init_done = cutlass.Boolean(False)
# group index of last tile
last_group_idx = cutlass.Int32(-1)
work_tile = tile_sched.initial_work_tile_info()
ab_producer_state = pipeline.make_pipeline_state(
pipeline.PipelineUserType.Producer, self.num_ab_stage
)
while work_tile.is_valid_tile:
cur_tile_coord = work_tile.tile_idx
grouped_gemm_cta_tile_info = group_gemm_ts_helper.delinearize_z(
cur_tile_coord,
problem_sizes_mnkl,
)
cur_k_tile_cnt = grouped_gemm_cta_tile_info.cta_tile_count_k
cur_group_idx = grouped_gemm_cta_tile_info.group_idx
is_group_changed = cur_group_idx != last_group_idx
# skip tensormap update if we're working on the same group
if is_group_changed:
real_tensor_a = self.make_tensor_abc_for_tensormap_update(
cur_group_idx,
self.a_dtype,
(
grouped_gemm_cta_tile_info.problem_shape_m,
grouped_gemm_cta_tile_info.problem_shape_n,
grouped_gemm_cta_tile_info.problem_shape_k,
),
ptrs_abc,
0, # 0 for tensor A
)
real_tensor_b = self.make_tensor_abc_for_tensormap_update(
cur_group_idx,
self.b_dtype,
(
grouped_gemm_cta_tile_info.problem_shape_m,
grouped_gemm_cta_tile_info.problem_shape_n,
grouped_gemm_cta_tile_info.problem_shape_k,
),
ptrs_abc,
1, # 1 for tensor B
)
real_tensor_sfa = self.make_tensor_sfasfb_for_tensormap_update(
cur_group_idx,
self.sf_dtype,
(
grouped_gemm_cta_tile_info.problem_shape_m,
grouped_gemm_cta_tile_info.problem_shape_n,
grouped_gemm_cta_tile_info.problem_shape_k,
),
ptrs_sfasfb,
0, # 0 for tensor SFA
)
real_tensor_sfb = self.make_tensor_sfasfb_for_tensormap_update(
cur_group_idx,
self.sf_dtype,
(
grouped_gemm_cta_tile_info.problem_shape_m,
grouped_gemm_cta_tile_info.problem_shape_n,
grouped_gemm_cta_tile_info.problem_shape_k,
),
ptrs_sfasfb,
1, # 1 for tensor SFB
)
if tensormap_init_done == False:
# wait tensormap initialization complete
self.tensormap_ab_init_barrier.arrive_and_wait()
tensormap_init_done = True
tensormap_manager.update_tensormap(
(
real_tensor_a,
real_tensor_b,
real_tensor_sfa,
real_tensor_sfb,
),
(tma_atom_a, tma_atom_b, tma_atom_sfa, tma_atom_sfb),
(
tensormap_a_gmem_ptr,
tensormap_b_gmem_ptr,
tensormap_sfa_gmem_ptr,
tensormap_sfb_gmem_ptr,
),
self.tma_warp_id,
(
tensormap_a_smem_ptr,
tensormap_b_smem_ptr,
tensormap_sfa_smem_ptr,
tensormap_sfb_smem_ptr,
),
)
mma_tile_coord_mnl = (
grouped_gemm_cta_tile_info.cta_tile_idx_m
// cute.size(tiled_mma.thr_id.shape),
grouped_gemm_cta_tile_info.cta_tile_idx_n,
0,
)
#
# Slice to per mma tile index
#
# ((atom_v, rest_v), RestK)
tAgA_slice = tAgA[
(None, mma_tile_coord_mnl[0], None, mma_tile_coord_mnl[2])
]
# ((atom_v, rest_v), RestK)
tBgB_slice = tBgB[
(None, mma_tile_coord_mnl[1], None, mma_tile_coord_mnl[2])
]
# ((atom_v, rest_v), RestK)
tAgSFA_slice = tAgSFA[
(None, mma_tile_coord_mnl[0], None, mma_tile_coord_mnl[2])
]
# ((atom_v, rest_v), RestK)
tBgSFB_slice = tBgSFB[
(None, mma_tile_coord_mnl[1], None, mma_tile_coord_mnl[2])
]
# Peek (try_wait) AB buffer empty for k_tile = prefetch_k_tile_cnt
ab_producer_state.reset_count()
peek_ab_empty_status = cutlass.Boolean(1)
if ab_producer_state.count < cur_k_tile_cnt:
peek_ab_empty_status = ab_pipeline.producer_try_acquire(
ab_producer_state
)
if is_group_changed:
tensormap_manager.fence_tensormap_update(tensormap_a_gmem_ptr)
tensormap_manager.fence_tensormap_update(tensormap_b_gmem_ptr)
tensormap_manager.fence_tensormap_update(tensormap_sfa_gmem_ptr)
tensormap_manager.fence_tensormap_update(tensormap_sfb_gmem_ptr)
#
# Tma load loop
#
for k_tile in cutlass.range(0, cur_k_tile_cnt, 1, unroll=1):
# Conditionally wait for AB buffer empty
ab_pipeline.producer_acquire(
ab_producer_state, peek_ab_empty_status
)
# TMA load A/B/SFA/SFB
cute.copy(
tma_atom_a,
tAgA_slice[(None, ab_producer_state.count)],
tAsA[(None, ab_producer_state.index)],
tma_bar_ptr=ab_pipeline.producer_get_barrier(ab_producer_state),
mcast_mask=a_full_mcast_mask,
tma_desc_ptr=tensormap_manager.get_tensormap_ptr(
tensormap_a_gmem_ptr,
cute.AddressSpace.generic,
),
cache_policy=cutlass.Int64(cutlass.Int64(self.cache_policy).ir_value()),
)
cute.copy(
tma_atom_b,
tBgB_slice[(None, ab_producer_state.count)],
tBsB[(None, ab_producer_state.index)],
tma_bar_ptr=ab_pipeline.producer_get_barrier(ab_producer_state),
mcast_mask=b_full_mcast_mask,
tma_desc_ptr=tensormap_manager.get_tensormap_ptr(
tensormap_b_gmem_ptr,
cute.AddressSpace.generic,
),
cache_policy=cutlass.Int64(cutlass.Int64(self.cache_policy).ir_value()),
)
cute.copy(
tma_atom_sfa,
tAgSFA_slice[(None, ab_producer_state.count)],
tAsSFA[(None, ab_producer_state.index)],
tma_bar_ptr=ab_pipeline.producer_get_barrier(ab_producer_state),
mcast_mask=sfa_full_mcast_mask,
tma_desc_ptr=tensormap_manager.get_tensormap_ptr(
tensormap_sfa_gmem_ptr,
cute.AddressSpace.generic,
),
cache_policy=cutlass.Int64(cutlass.Int64(self.cache_policy).ir_value()),
)
cute.copy(
tma_atom_sfb,
tBgSFB_slice[(None, ab_producer_state.count)],
tBsSFB[(None, ab_producer_state.index)],
tma_bar_ptr=ab_pipeline.producer_get_barrier(ab_producer_state),
mcast_mask=sfb_full_mcast_mask,
tma_desc_ptr=tensormap_manager.get_tensormap_ptr(
tensormap_sfb_gmem_ptr,
cute.AddressSpace.generic,
),
cache_policy=cutlass.Int64(cutlass.Int64(self.cache_policy).ir_value()),
)
# Peek (try_wait) AB buffer empty for k_tile = prefetch_k_tile_cnt + k_tile + 1
ab_producer_state.advance()
peek_ab_empty_status = cutlass.Boolean(1)
if ab_producer_state.count < cur_k_tile_cnt:
peek_ab_empty_status = ab_pipeline.producer_try_acquire(
ab_producer_state
)
#
# Advance to next tile
#
tile_sched.advance_to_next_work()
work_tile = tile_sched.get_current_work()
last_group_idx = cur_group_idx
#
# Wait A/B buffer empty
#
ab_pipeline.producer_tail(ab_producer_state)
#
# Specialized MMA warp
#
if warp_idx == self.mma_warp_id:
#
# Initialize tensormaps for A, B, SFA and SFB
#
tensormap_manager.init_tensormap_from_atom(
tma_atom_a, tensormap_a_smem_ptr, self.mma_warp_id
)
tensormap_manager.init_tensormap_from_atom(
tma_atom_b, tensormap_b_smem_ptr, self.mma_warp_id
)
tensormap_manager.init_tensormap_from_atom(
tma_atom_sfa, tensormap_sfa_smem_ptr, self.mma_warp_id
)
tensormap_manager.init_tensormap_from_atom(
tma_atom_sfb, tensormap_sfb_smem_ptr, self.mma_warp_id
)
# indicate tensormap initialization has finished
self.tensormap_ab_init_barrier.arrive_and_wait()
#
# Bar sync for retrieve tensor memory ptr from shared mem
#
tmem.wait_for_alloc()
#
# Retrieving tensor memory ptr and make accumulator/SFA/SFB tensor
#
# Make accumulator tmem tensor
acc_tmem_ptr = tmem.retrieve_ptr(
self.acc_dtype,
)
# (MMA, MMA_M, MMA_N, STAGE)
tCtAcc_base = cute.make_tensor(acc_tmem_ptr, tCtAcc_fake.layout)
# Make SFA tmem tensor
sfa_tmem_ptr = cute.recast_ptr(
acc_tmem_ptr + tcgen05.find_tmem_tensor_col_offset(tCtAcc_base),
dtype=self.sf_dtype,
)
# (MMA, MMA_M, MMA_K)
tCtSFA_layout = blockscaled_utils.make_tmem_layout_sfa(
tiled_mma,
self.mma_tiler,
self.sf_vec_size,
cute.slice_(sfa_smem_layout_staged, (None, None, None, 0)),
)
tCtSFA = cute.make_tensor(sfa_tmem_ptr, tCtSFA_layout)
# Make SFB tmem tensor
sfb_tmem_ptr = cute.recast_ptr(
acc_tmem_ptr
+ tcgen05.find_tmem_tensor_col_offset(tCtAcc_base)
+ tcgen05.find_tmem_tensor_col_offset(tCtSFA),
dtype=self.sf_dtype,
)
# (MMA, MMA_N, MMA_K)
tCtSFB_layout = blockscaled_utils.make_tmem_layout_sfb(
tiled_mma,
self.mma_tiler,
self.sf_vec_size,
cute.slice_(sfb_smem_layout_staged, (None, None, None, 0)),
)
tCtSFB = cute.make_tensor(sfb_tmem_ptr, tCtSFB_layout)
#
# Partition for S2T copy of SFA/SFB
#
tiled_copy_s2t_sfa, tCsSFA_compact_s2t, tCtSFA_compact_s2t = (
self.mainloop_s2t_copy_and_partition(sSFA, tCtSFA)
)
tiled_copy_s2t_sfb, tCsSFB_compact_s2t, tCtSFB_compact_s2t = (
self.mainloop_s2t_copy_and_partition(sSFB, tCtSFB)
)
#
# Persistent tile scheduling loop
#
tile_sched = utils.StaticPersistentTileScheduler.create(
tile_sched_params, cute.arch.block_idx(), grid_dim
)
# grouped gemm tile scheduler helper will compute the group index for the tile we're working on
group_gemm_ts_helper = utils.GroupedGemmTileSchedulerHelper(
group_count,
tile_sched_params,
self.cluster_tile_shape_mnk,
utils.create_initial_search_state(),
)
work_tile = tile_sched.initial_work_tile_info()
ab_consumer_state = pipeline.make_pipeline_state(
pipeline.PipelineUserType.Consumer, self.num_ab_stage
)
acc_producer_state = pipeline.make_pipeline_state(
pipeline.PipelineUserType.Producer, self.num_acc_stage
)
while work_tile.is_valid_tile:
cur_tile_coord = work_tile.tile_idx
# MMA warp is only interested in number of tiles along K dimension
(
cur_k_tile_cnt,
cur_group_idx,
) = group_gemm_ts_helper.search_cluster_tile_count_k(
cur_tile_coord,
problem_sizes_mnkl,
)
# (MMA, MMA_M, MMA_N)
tCtAcc = tCtAcc_base[(None, None, None, acc_producer_state.index)]
# Peek (try_wait) AB buffer full for k_tile = 0
ab_consumer_state.reset_count()
peek_ab_full_status = cutlass.Boolean(1)
if ab_consumer_state.count < cur_k_tile_cnt and is_leader_cta:
peek_ab_full_status = ab_pipeline.consumer_try_wait(
ab_consumer_state
)
#
# Wait for accumulator buffer empty
#
if is_leader_cta:
acc_pipeline.producer_acquire(acc_producer_state)
#
# Reset the ACCUMULATE field for each tile
#
tiled_mma.set(tcgen05.Field.ACCUMULATE, False)
#
# Mma mainloop
#
for k_tile in range(cur_k_tile_cnt):
if is_leader_cta:
# Conditionally wait for AB buffer full
ab_pipeline.consumer_wait(
ab_consumer_state, peek_ab_full_status
)
# Copy SFA/SFB from smem to tmem
s2t_stage_coord = (
None,
None,
None,
None,
ab_consumer_state.index,
)
tCsSFA_compact_s2t_staged = tCsSFA_compact_s2t[s2t_stage_coord]
tCsSFB_compact_s2t_staged = tCsSFB_compact_s2t[s2t_stage_coord]
cute.copy(
tiled_copy_s2t_sfa,
tCsSFA_compact_s2t_staged,
tCtSFA_compact_s2t,
)
cute.copy(
tiled_copy_s2t_sfb,
tCsSFB_compact_s2t_staged,
tCtSFB_compact_s2t,
)
# tCtAcc += tCrA * tCrSFA * tCrB * tCrSFB
num_kblocks = cute.size(tCrA, mode=[2])
for kblock_idx in cutlass.range(num_kblocks, unroll_full=True):
kblock_coord = (
None,
None,
kblock_idx,
ab_consumer_state.index,
)
# Set SFA/SFB tensor to tiled_mma
sf_kblock_coord = (None, None, kblock_idx)
tiled_mma.set(
tcgen05.Field.SFA,
tCtSFA[sf_kblock_coord].iterator,
)
tiled_mma.set(
tcgen05.Field.SFB,
tCtSFB[sf_kblock_coord].iterator,
)
cute.gemm(
tiled_mma,
tCtAcc,
tCrA[kblock_coord],
tCrB[kblock_coord],
tCtAcc,
)
# Enable accumulate on tCtAcc after first kblock
tiled_mma.set(tcgen05.Field.ACCUMULATE, True)
# Async arrive AB buffer empty
ab_pipeline.consumer_release(ab_consumer_state)
# Peek (try_wait) AB buffer full for k_tile = k_tile + 1
ab_consumer_state.advance()
peek_ab_full_status = cutlass.Boolean(1)
if ab_consumer_state.count < cur_k_tile_cnt:
if is_leader_cta:
peek_ab_full_status = ab_pipeline.consumer_try_wait(
ab_consumer_state
)
#
# Async arrive accumulator buffer full
#
if is_leader_cta:
acc_pipeline.producer_commit(acc_producer_state)
acc_producer_state.advance()
#
# Advance to next tile
#
tile_sched.advance_to_next_work()
work_tile = tile_sched.get_current_work()
#
# Wait for accumulator buffer empty
#
acc_pipeline.producer_tail(acc_producer_state)
#
# Specialized epilogue warps
#
if warp_idx < self.mma_warp_id:
# initialize tensorap for C
tensormap_manager.init_tensormap_from_atom(
tma_atom_c,
tensormap_c_smem_ptr,
self.epilog_warp_id[0],
)
#
# Alloc tensor memory buffer
#
tmem.allocate(self.num_tmem_alloc_cols)
tmem.wait_for_alloc()
#
# Retrieving tensor memory ptr and make accumulator tensor
#
acc_tmem_ptr = tmem.retrieve_ptr(self.acc_dtype)
# (MMA, MMA_M, MMA_N, STAGE)
tCtAcc_base = cute.make_tensor(acc_tmem_ptr, tCtAcc_fake.layout)
### Start from here
#
# Partition for epilogue
#
epi_tidx = tidx
tiled_copy_t2r, tTR_tAcc_base, tTR_rAcc = (
self.epilog_tmem_copy_and_partition(
epi_tidx, tCtAcc_base, tCgC, epi_tile, use_2cta_instrs
)
)
tTR_rC = cute.make_rmem_tensor(tTR_rAcc.shape, self.c_dtype)
tiled_copy_r2s, tRS_rC, tRS_sC = self.epilog_smem_copy_and_partition(
tiled_copy_t2r, tTR_rC, epi_tidx, sC
)
tma_atom_c, bSG_sC, bSG_gC_partitioned = (
self.epilog_gmem_copy_and_partition(
epi_tidx, tma_atom_c, tCgC, epi_tile, sC
)
)
#
# Persistent tile scheduling loop
#
tile_sched = utils.StaticPersistentTileScheduler.create(
tile_sched_params, cute.arch.block_idx(), grid_dim
)
# grouped gemm tile scheduler helper will compute the group index for the tile we're working on
group_gemm_ts_helper = utils.GroupedGemmTileSchedulerHelper(
group_count,
tile_sched_params,
self.cluster_tile_shape_mnk,
utils.create_initial_search_state(),
)
work_tile = tile_sched.initial_work_tile_info()
acc_consumer_state = pipeline.make_pipeline_state(
pipeline.PipelineUserType.Consumer, self.num_acc_stage
)
# Threads/warps participating in tma store pipeline
c_producer_group = pipeline.CooperativeGroup(
pipeline.Agent.Thread,
32 * len(self.epilog_warp_id),
)
c_pipeline = pipeline.PipelineTmaStore.create(
num_stages=self.num_c_stage,
producer_group=c_producer_group,
)
# group index to start searching
last_group_idx = cutlass.Int32(-1)
while work_tile.is_valid_tile:
cur_tile_coord = work_tile.tile_idx
grouped_gemm_cta_tile_info = group_gemm_ts_helper.delinearize_z(
cur_tile_coord,
problem_sizes_mnkl,
)
cur_group_idx = grouped_gemm_cta_tile_info.group_idx
is_group_changed = cur_group_idx != last_group_idx
if is_group_changed:
# construct tensor c based on real shape, stride information
real_tensor_c = self.make_tensor_abc_for_tensormap_update(
cur_group_idx,
self.c_dtype,
(
grouped_gemm_cta_tile_info.problem_shape_m,
grouped_gemm_cta_tile_info.problem_shape_n,
grouped_gemm_cta_tile_info.problem_shape_k,
),
ptrs_abc,
2, # 2 for tensor C
)
tensormap_manager.update_tensormap(
((real_tensor_c),),
((tma_atom_c),),
((tensormap_c_gmem_ptr),),
self.epilog_warp_id[0],
(tensormap_c_smem_ptr,),
)
mma_tile_coord_mnl = (
grouped_gemm_cta_tile_info.cta_tile_idx_m
// cute.size(tiled_mma.thr_id.shape),
grouped_gemm_cta_tile_info.cta_tile_idx_n,
0,
)
cur_k_tile_cnt = grouped_gemm_cta_tile_info.cta_tile_count_k
#
# Slice to per mma tile index
#
# ((ATOM_V, REST_V), EPI_M, EPI_N)
bSG_gC = bSG_gC_partitioned[
(
None,
None,
None,
*mma_tile_coord_mnl,
)
]
# Set tensor memory buffer for current tile
# (T2R, T2R_M, T2R_N, EPI_M, EPI_M)
tTR_tAcc = tTR_tAcc_base[
(None, None, None, None, None, acc_consumer_state.index)
]
#
# Wait for accumulator buffer full
#
acc_pipeline.consumer_wait(acc_consumer_state)
tTR_tAcc = cute.group_modes(tTR_tAcc, 3, cute.rank(tTR_tAcc))
bSG_gC = cute.group_modes(bSG_gC, 1, cute.rank(bSG_gC))
if is_group_changed:
if warp_idx == self.epilog_warp_id[0]:
tensormap_manager.fence_tensormap_update(tensormap_c_gmem_ptr)
#
# Store accumulator to global memory in subtiles
#
subtile_cnt = cute.size(tTR_tAcc.shape, mode=[3])
num_prev_subtiles = tile_sched.num_tiles_executed * subtile_cnt
for subtile_idx in range(subtile_cnt):
#
# Load accumulator from tensor memory buffer to register
#
tTR_tAcc_mn = tTR_tAcc[(None, None, None, subtile_idx)]
cute.copy(tiled_copy_t2r, tTR_tAcc_mn, tTR_rAcc)
#
# Convert to C type
#
acc_vec = tiled_copy_r2s.retile(tTR_rAcc).load()
tRS_rC.store(acc_vec.to(self.c_dtype))
#
# Store C to shared memory
#
c_buffer = (num_prev_subtiles + subtile_idx) % self.num_c_stage
cute.copy(
tiled_copy_r2s,
tRS_rC,
tRS_sC[(None, None, None, c_buffer)],
)
# Fence and barrier to make sure shared memory store is visible to TMA store
cute.arch.fence_proxy(
cute.arch.ProxyKind.async_shared,
space=cute.arch.SharedSpace.shared_cta,
)
self.epilog_sync_barrier.arrive_and_wait()
#
# TMA store C to global memory
#
if warp_idx == self.epilog_warp_id[0]:
cute.copy(
tma_atom_c,
bSG_sC[(None, c_buffer)],
bSG_gC[(None, subtile_idx)],
tma_desc_ptr=tensormap_manager.get_tensormap_ptr(
tensormap_c_gmem_ptr,
cute.AddressSpace.generic,
),
)
# Fence and barrier to make sure shared memory store is visible to TMA store
c_pipeline.producer_commit()
c_pipeline.producer_acquire()
self.epilog_sync_barrier.arrive_and_wait()
#
# Async arrive accumulator buffer empty
#
with cute.arch.elect_one():
acc_pipeline.consumer_release(acc_consumer_state)
acc_consumer_state.advance()
#
# Advance to next tile
#
tile_sched.advance_to_next_work()
work_tile = tile_sched.get_current_work()
last_group_idx = cur_group_idx
#
# Dealloc the tensor memory buffer
#
if warp_idx == self.epilog_warp_id[0]:
cute.arch.relinquish_tmem_alloc_permit(is_two_cta=use_2cta_instrs)
self.epilog_sync_barrier.arrive_and_wait()
if warp_idx == self.epilog_warp_id[0]:
if use_2cta_instrs:
pipeline_init_arrive(cluster_shape_mn=self.cluster_shape_mn)
pipeline_init_wait(cluster_shape_mn=self.cluster_shape_mn)
#
# Wait for C store complete
#
c_pipeline.producer_tail()
tmem.free(acc_tmem_ptr)
@cute.jit
def make_tensor_abc_for_tensormap_update(
self,
group_idx: cutlass.Int32,
dtype: Type[cutlass.Numeric],
problem_shape_mnk: tuple[cutlass.Int32, cutlass.Int32, cutlass.Int32],
tensor_address_abc: cute.Tensor,
tensor_index: int,
):
# Retrieve the pointer for this group and tensor index
ptr_i64 = tensor_address_abc[(group_idx, tensor_index)]
tensor_gmem_ptr = cute.make_ptr(
dtype, ptr_i64, cute.AddressSpace.gmem, assumed_align=16
)
# Helper constants
c0 = cutlass.Int32(0)
c1 = cutlass.Int32(1)
c2 = cutlass.Int32(2)
# Reconstruct strides assuming contiguous inputs
if cutlass.const_expr(tensor_index == 0): # Tensor A: [M, K]
m = problem_shape_mnk[0]
k = problem_shape_mnk[2]
# Logic: Input A is [M, K/2] packed.
# Contiguous stride(0) is K/2. Your code used stride(0)*2 = K.
# Contiguous stride(1) is 1. Your code used stride(1)*2 = 2.
stride_mn = k
stride_k = c2
return cute.make_tensor(
tensor_gmem_ptr,
cute.make_layout((m, k, c1), stride=(stride_mn, stride_k, c0)),
)
elif cutlass.const_expr(tensor_index == 1): # Tensor B: [N, K]
n = problem_shape_mnk[1]
k = problem_shape_mnk[2]
# Logic: Input B is [N, K/2] packed. Same logic as A.
stride_mn = k
stride_k = c2
return cute.make_tensor(
tensor_gmem_ptr,
cute.make_layout((n, k, c1), stride=(stride_mn, stride_k, c0)),
)
else: # Tensor C: [M, N]
m = problem_shape_mnk[0]
n = problem_shape_mnk[1]
# Logic: Input C is [M, N] float16.
# Contiguous stride(0) is N.
# Contiguous stride(1) is 1.
stride_mn = n
stride_k = c1
return cute.make_tensor(
tensor_gmem_ptr,
cute.make_layout((m, n, c1), stride=(stride_mn, stride_k, c0)),
)
@cute.jit
def make_tensor_sfasfb_for_tensormap_update(
self,
group_idx: cutlass.Int32,
dtype: Type[cutlass.Numeric],
problem_shape_mnk: tuple[cutlass.Int32, cutlass.Int32, cutlass.Int32],
tensor_address_sfasfb: cute.Tensor,
tensor_index: int,
):
"""Extract tensor address for a given group and construct a global tensor for SFA or SFB.
This function is used within the kernel to dynamically create a CUTE tensor
representing SFA or SFB for the current group being processed, using the
group-specific address, shape information.
:param group_idx: The index of the current group within the grouped GEMM.
:type group_idx: cutlass.Int32
:param dtype: The data type of the tensor elements (e.g., cutlass.Float16).
:type dtype: Type[cutlass.Numeric]
:param problem_shape_mnk: The (M, N, K) problem shape for the current group.
:type problem_shape_mnk: tuple[cutlass.Int32, cutlass.Int32, cutlass.Int32]
:param tensor_address_sfasfb: Tensor containing global memory addresses for SFA, SFB for all groups. Layout: (group_count, 2).
:type tensor_address_sfasfb: cute.Tensor
:param tensor_index: Specifies which tensor to create: 0 for SFA, 1 for SFB.
:type tensor_index: int
:return: A CUTE tensor representing the requested global memory tensor (SFA, SFB) for the specified group.
:rtype: cute.Tensor
:raises TypeError: If the provided dtype is not a subclass of cutlass.Numeric.
"""
ptr_i64 = tensor_address_sfasfb[(group_idx, tensor_index)]
if cutlass.const_expr(
not isclass(dtype) or not issubclass(dtype, cutlass.Numeric)
):
raise TypeError(
f"dtype must be a type of cutlass.Numeric, got {type(dtype)}"
)
tensor_gmem_ptr = cute.make_ptr(
dtype, ptr_i64, cute.AddressSpace.gmem, assumed_align=16
)
c1 = cutlass.Int32(1)
if cutlass.const_expr(tensor_index == 0): # tensor SFA
m = problem_shape_mnk[0]
k = problem_shape_mnk[2]
sfa_layout = blockscaled_utils.tile_atom_to_shape_SF(
(m, k, c1), self.sf_vec_size
)
return cute.make_tensor(
tensor_gmem_ptr,
sfa_layout,
)
else: # tensor SFB
n = problem_shape_mnk[1]
k = problem_shape_mnk[2]
sfb_layout = blockscaled_utils.tile_atom_to_shape_SF(
(n, k, c1), self.sf_vec_size
)
return cute.make_tensor(
tensor_gmem_ptr,
sfb_layout,
)
def mainloop_s2t_copy_and_partition(
self,
sSF: cute.Tensor,
tSF: cute.Tensor,
) -> Tuple[cute.TiledCopy, cute.Tensor, cute.Tensor]:
"""
Make tiledCopy for smem to tmem load for scale factor tensor, then use it to partition smem memory (source) and tensor memory (destination).
:param sSF: The scale factor tensor in smem
:type sSF: cute.Tensor
:param tSF: The scale factor tensor in tmem
:type tSF: cute.Tensor
:return: A tuple containing (tiled_copy_s2t, tCsSF_compact_s2t, tCtSF_compact_s2t) where:
- tiled_copy_s2t: The tiled copy operation for smem to tmem load for scale factor tensor(s2t)
- tCsSF_compact_s2t: The partitioned scale factor tensor in smem
- tSF_compact_s2t: The partitioned scale factor tensor in tmem
:rtype: Tuple[cute.TiledCopy, cute.Tensor, cute.Tensor]
"""
# (MMA, MMA_MN, MMA_K, STAGE)
tCsSF_compact = cute.filter_zeros(sSF)
# (MMA, MMA_MN, MMA_K)
tCtSF_compact = cute.filter_zeros(tSF)
# Make S2T CopyAtom and tiledCopy
copy_atom_s2t = cute.make_copy_atom(
tcgen05.Cp4x32x128bOp(self.cta_group),
self.sf_dtype,
)
tiled_copy_s2t = tcgen05.make_s2t_copy(copy_atom_s2t, tCtSF_compact)
thr_copy_s2t = tiled_copy_s2t.get_slice(0)
# ((ATOM_V, REST_V), Rest_Tiler, MMA_MN, MMA_K, STAGE)
tCsSF_compact_s2t_ = thr_copy_s2t.partition_S(tCsSF_compact)
# ((ATOM_V, REST_V), Rest_Tiler, MMA_MN, MMA_K, STAGE)
tCsSF_compact_s2t = tcgen05.get_s2t_smem_desc_tensor(
tiled_copy_s2t, tCsSF_compact_s2t_
)
# ((ATOM_V, REST_V), Rest_Tiler, MMA_MN, MMA_K)
tCtSF_compact_s2t = thr_copy_s2t.partition_D(tCtSF_compact)
return tiled_copy_s2t, tCsSF_compact_s2t, tCtSF_compact_s2t
def epilog_tmem_copy_and_partition(
self,
tidx: cutlass.Int32,
tAcc: cute.Tensor,
gC_mnl: cute.Tensor,
epi_tile: cute.Tile,
use_2cta_instrs: Union[cutlass.Boolean, bool],
) -> Tuple[cute.TiledCopy, cute.Tensor, cute.Tensor]:
"""
Make tiledCopy for tensor memory load, then use it to partition tensor memory (source) and register array (destination).
:param tidx: The thread index in epilogue warp groups
:type tidx: cutlass.Int32
:param tAcc: The accumulator tensor to be copied and partitioned
:type tAcc: cute.Tensor
:param gC_mnl: The global tensor C
:type gC_mnl: cute.Tensor
:param epi_tile: The epilogue tiler
:type epi_tile: cute.Tile
:param use_2cta_instrs: Whether use_2cta_instrs is enabled
:type use_2cta_instrs: bool
:return: A tuple containing (tiled_copy_t2r, tTR_tAcc, tTR_rAcc) where:
- tiled_copy_t2r: The tiled copy operation for tmem to register copy(t2r)
- tTR_tAcc: The partitioned accumulator tensor
- tTR_rAcc: The accumulated tensor in register used to hold t2r results
:rtype: Tuple[cute.TiledCopy, cute.Tensor, cute.Tensor]
"""
# Make tiledCopy for tensor memory load
copy_atom_t2r = sm100_utils.get_tmem_load_op(
self.cta_tile_shape_mnk,
self.c_layout,
self.c_dtype,
self.acc_dtype,
epi_tile,
use_2cta_instrs,
)
# (EPI_TILE_M, EPI_TILE_N, EPI_M, EPI_N, STAGE)
tAcc_epi = cute.flat_divide(
tAcc[((None, None), 0, 0, None)],
epi_tile,
)
# (EPI_TILE_M, EPI_TILE_N)
tiled_copy_t2r = tcgen05.make_tmem_copy(
copy_atom_t2r, tAcc_epi[(None, None, 0, 0, 0)]
)
thr_copy_t2r = tiled_copy_t2r.get_slice(tidx)
# (T2R, T2R_M, T2R_N, EPI_M, EPI_M, STAGE)
tTR_tAcc = thr_copy_t2r.partition_S(tAcc_epi)
# (EPI_TILE_M, EPI_TILE_N, EPI_M, EPI_N, RestM, RestN, RestL)
gC_mnl_epi = cute.flat_divide(
gC_mnl[((None, None), 0, 0, None, None, None)], epi_tile
)
# (T2R, T2R_M, T2R_N, EPI_M, EPI_N, RestM, RestN, RestL)
tTR_gC = thr_copy_t2r.partition_D(gC_mnl_epi)
# (T2R, T2R_M, T2R_N)
tTR_rAcc = cute.make_rmem_tensor(
tTR_gC[(None, None, None, 0, 0, 0, 0, 0)].shape, self.acc_dtype
)
return tiled_copy_t2r, tTR_tAcc, tTR_rAcc
def epilog_smem_copy_and_partition(
self,
tiled_copy_t2r: cute.TiledCopy,
tTR_rC: cute.Tensor,
tidx: cutlass.Int32,
sC: cute.Tensor,
) -> Tuple[cute.TiledCopy, cute.Tensor, cute.Tensor]:
"""
Make tiledCopy for shared memory store, then use it to partition register array (source) and shared memory (destination).
:param tiled_copy_t2r: The tiled copy operation for tmem to register copy(t2r)
:type tiled_copy_t2r: cute.TiledCopy
:param tTR_rC: The partitioned accumulator tensor
:type tTR_rC: cute.Tensor
:param tidx: The thread index in epilogue warp groups
:type tidx: cutlass.Int32
:param sC: The shared memory tensor to be copied and partitioned
:type sC: cute.Tensor
:type sepi: cute.Tensor
:return: A tuple containing (tiled_copy_r2s, tRS_rC, tRS_sC) where:
- tiled_copy_r2s: The tiled copy operation for register to smem copy(r2s)
- tRS_rC: The partitioned tensor C (register source)
- tRS_sC: The partitioned tensor C (smem destination)
:rtype: Tuple[cute.TiledCopy, cute.Tensor, cute.Tensor]
"""
copy_atom_r2s = sm100_utils.get_smem_store_op(
self.c_layout, self.c_dtype, self.acc_dtype, tiled_copy_t2r
)
tiled_copy_r2s = cute.make_tiled_copy_D(copy_atom_r2s, tiled_copy_t2r)
# (R2S, R2S_M, R2S_N, PIPE_D)
thr_copy_r2s = tiled_copy_r2s.get_slice(tidx)
tRS_sC = thr_copy_r2s.partition_D(sC)
# (R2S, R2S_M, R2S_N)
tRS_rC = tiled_copy_r2s.retile(tTR_rC)
return tiled_copy_r2s, tRS_rC, tRS_sC
def epilog_gmem_copy_and_partition(
self,
tidx: cutlass.Int32,
atom: Union[cute.CopyAtom, cute.TiledCopy],
gC_mnl: cute.Tensor,
epi_tile: cute.Tile,
sC: cute.Tensor,
) -> Tuple[cute.CopyAtom, cute.Tensor, cute.Tensor]:
"""Make tiledCopy for global memory store, then use it to:
partition shared memory (source) and global memory (destination) for TMA store version.
:param tidx: The thread index in epilogue warp groups
:type tidx: cutlass.Int32
:param atom: The copy_atom_c to be used for TMA store version, or tiled_copy_t2r for none TMA store version
:type atom: cute.CopyAtom or cute.TiledCopy
:param gC_mnl: The global tensor C
:type gC_mnl: cute.Tensor
:param epi_tile: The epilogue tiler
:type epi_tile: cute.Tile
:param sC: The shared memory tensor to be copied and partitioned
:type sC: cute.Tensor
:return: A tuple containing (tma_atom_c, bSG_sC, bSG_gC) where:
- tma_atom_c: The TMA copy atom
- bSG_sC: The partitioned shared memory tensor C
- bSG_gC: The partitioned global tensor C
:rtype: Tuple[cute.CopyAtom, cute.Tensor, cute.Tensor]
"""
# (EPI_TILE_M, EPI_TILE_N, EPI_M, EPI_N, RestM, RestN, RestL)
gC_epi = cute.flat_divide(
gC_mnl[((None, None), 0, 0, None, None, None)], epi_tile
)
tma_atom_c = atom
sC_for_tma_partition = cute.group_modes(sC, 0, 2)
gC_for_tma_partition = cute.group_modes(gC_epi, 0, 2)
# ((ATOM_V, REST_V), EPI_M, EPI_N)
# ((ATOM_V, REST_V), EPI_M, EPI_N, RestM, RestN, RestL)
bSG_sC, bSG_gC = cpasync.tma_partition(
tma_atom_c,
0,
cute.make_layout(1),
sC_for_tma_partition,
gC_for_tma_partition,
)
return tma_atom_c, bSG_sC, bSG_gC
@staticmethod
def _compute_stages(
tiled_mma: cute.TiledMma,
mma_tiler_mnk: Tuple[int, int, int],
a_dtype: Type[cutlass.Numeric],
b_dtype: Type[cutlass.Numeric],
epi_tile: cute.Tile,
c_dtype: Type[cutlass.Numeric],
c_layout: utils.LayoutEnum,
sf_dtype: Type[cutlass.Numeric],
sf_vec_size: int,
smem_capacity: int,
occupancy: int,
) -> Tuple[int, int, int]:
"""Computes the number of stages for A/B/C operands based on heuristics.
:param tiled_mma: The tiled MMA object defining the core computation.
:type tiled_mma: cute.TiledMma
:param mma_tiler_mnk: The shape (M, N, K) of the MMA tiler.
:type mma_tiler_mnk: tuple[int, int, int]
:param a_dtype: Data type of operand A.
:type a_dtype: type[cutlass.Numeric]
:param b_dtype: Data type of operand B.
:type b_dtype: type[cutlass.Numeric]
:param epi_tile: The epilogue tile shape.
:type epi_tile: cute.Tile
:param c_dtype: Data type of operand C (output).
:type c_dtype: type[cutlass.Numeric]
:param c_layout: Layout enum of operand C.
:type c_layout: utils.LayoutEnum
:param sf_dtype: Data type of Scale factor.
:type sf_dtype: type[cutlass.Numeric]
:param sf_vec_size: Scale factor vector size.
:type sf_vec_size: int
:param smem_capacity: Total available shared memory capacity in bytes.
:type smem_capacity: int
:param occupancy: Target number of CTAs per SM (occupancy).
:type occupancy: int
:return: A tuple containing the computed number of stages for:
(ACC stages, A/B operand stages, C stages)
:rtype: tuple[int, int, int]
"""
# ACC stages
num_acc_stage = 1 if mma_tiler_mnk[1] == 256 else 2
# Default C stages
num_c_stage = 2
# Calculate smem layout and size for one stage of A, B, SFA, SFB and C
a_smem_layout_stage_one = sm100_utils.make_smem_layout_a(
tiled_mma,
mma_tiler_mnk,
a_dtype,
1, # a tmp 1 stage is provided
)
b_smem_layout_staged_one = sm100_utils.make_smem_layout_b(
tiled_mma,
mma_tiler_mnk,
b_dtype,
1, # a tmp 1 stage is provided
)
sfa_smem_layout_staged_one = blockscaled_utils.make_smem_layout_sfa(
tiled_mma,
mma_tiler_mnk,
sf_vec_size,
1, # a tmp 1 stage is provided
)
sfb_smem_layout_staged_one = blockscaled_utils.make_smem_layout_sfb(
tiled_mma,
mma_tiler_mnk,
sf_vec_size,
1, # a tmp 1 stage is provided
)
c_smem_layout_staged_one = sm100_utils.make_smem_layout_epi(
c_dtype,
c_layout,
epi_tile,
1,
)
ab_bytes_per_stage = (
cute.size_in_bytes(a_dtype, a_smem_layout_stage_one)
+ cute.size_in_bytes(b_dtype, b_smem_layout_staged_one)
+ cute.size_in_bytes(sf_dtype, sfa_smem_layout_staged_one)
+ cute.size_in_bytes(sf_dtype, sfb_smem_layout_staged_one)
)
mbar_helpers_bytes = 1024
c_bytes_per_stage = cute.size_in_bytes(c_dtype, c_smem_layout_staged_one)
c_bytes = c_bytes_per_stage * num_c_stage
# Calculate A/B/SFA/SFB stages:
# Start with total smem per CTA (capacity / occupancy)
# Subtract reserved bytes and initial C stages bytes
# Divide remaining by bytes needed per A/B/SFA/SFB stage
num_ab_stage = (
smem_capacity // occupancy - (mbar_helpers_bytes + c_bytes)
) // ab_bytes_per_stage
# Refine epilogue stages:
# Calculate remaining smem after allocating for A/B/SFA/SFB stages and reserved bytes
# Add remaining unused smem to epilogue
num_c_stage += (
smem_capacity
- occupancy * ab_bytes_per_stage * num_ab_stage
- occupancy * (mbar_helpers_bytes + c_bytes)
) // (occupancy * c_bytes_per_stage)
return num_acc_stage, num_ab_stage, num_c_stage
@staticmethod
def _compute_grid(
total_num_clusters: int,
cluster_shape_mn: tuple[int, int],
max_active_clusters: cutlass.Constexpr[int],
) -> tuple[utils.PersistentTileSchedulerParams, tuple[int, int, int]]:
"""Compute tile scheduler parameters and grid shape for grouped GEMM operations.
:param total_num_clusters: Total number of clusters to process across all groups.
:type total_num_clusters: int
:param cluster_shape_mn: Shape of each cluster in M, N dimensions.
:type cluster_shape_mn: tuple[int, int]
:param max_active_clusters: Maximum number of active clusters.
:type max_active_clusters: cutlass.Constexpr[int]
:return: A tuple containing:
- tile_sched_params: Parameters for the persistent tile scheduler.
- grid: Grid shape for kernel launch.
:rtype: tuple[utils.PersistentTileSchedulerParams, tuple[int, ...]]
"""
# Create problem shape with M, N dimensions from cluster shape
# and L dimension representing the total number of clusters.
problem_shape_ntile_mnl = (
cluster_shape_mn[0],
cluster_shape_mn[1],
cutlass.Int32(total_num_clusters),
)
tile_sched_params = utils.PersistentTileSchedulerParams(
problem_shape_ntile_mnl, (*cluster_shape_mn, 1)
)
grid = utils.StaticPersistentTileScheduler.get_grid_shape(
tile_sched_params, max_active_clusters
)
return tile_sched_params, grid
@staticmethod
def _get_mbar_smem_bytes(**kwargs_stages: int) -> int:
"""Calculate shared memory consumption for memory barriers based on provided stages.
Each stage requires 2 barriers, and each barrier consumes 8 bytes of shared memory.
The total consumption is the sum across all provided stages. This function calculates the total
shared memory needed for these barriers.
:param kwargs_stages: Variable keyword arguments where each key is a stage name
(e.g., num_acc_stage, num_ab_stage) and each value is the
number of stages of that type.
:type kwargs_stages: int
:return: Total shared memory bytes required for all memory barriers.
:rtype: int
"""
num_barriers_per_stage = 2
num_bytes_per_barrier = 8
mbar_smem_consumption = sum(
[
num_barriers_per_stage * num_bytes_per_barrier * stage
for stage in kwargs_stages.values()
]
)
return mbar_smem_consumption
# Size of smem we reserved for mbarrier, tensor memory management and tensormap update
reserved_smem_bytes = 1024
bytes_per_tensormap = 128
num_tensormaps = 5
# size of smem used for tensor memory management
tensor_memory_management_bytes = 12
# Global cache for compiled kernels (keyed by group size)
_compiled_kernel_cache = {}
# This function is used to compile the kernel once and cache it and then allow users to
# run the kernel multiple times to get more accurate timing results.
def compile_kernel(problem_sizes):
"""
Compile the kernel once and cache it using problem_sizes as the key.
This should be called before any timing measurements.
Returns:
The compiled kernel function
"""
global _compiled_kernel_cache
_, n, k, _ = problem_sizes[0]
# Convert problem_sizes list to a hashable tuple for use as dictionary key
cache_key = f"{len(problem_sizes)}_{n}_{k}"
# Check if we already have a compiled kernel for these problem sizes
if cache_key in _compiled_kernel_cache:
return _compiled_kernel_cache[cache_key]
cute_ptr_of_tensor_of_problem_sizes = make_ptr(
cutlass.Int32, 0, cute.AddressSpace.gmem, assumed_align=16,
)
cute_ptr_of_tensor_of_abc_ptrs = make_ptr(
cutlass.Int64, 0, cute.AddressSpace.gmem, assumed_align=16,
)
cute_ptr_of_tensor_of_sfasfb_ptrs = make_ptr(
cutlass.Int64, 0, cute.AddressSpace.gmem, assumed_align=16,
)
mma_tiler_mn, cluster_shape_mn, _, _ = config_map.get((n, k), ((128, 128), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_FIRST))
total_num_clusters = cutlass.Int32(1)
num_groups = cutlass.Int32(len(problem_sizes))
# Each cluster needs its own set of tensormaps (one for A, B, SFA, SFB)
# Shape: (total_num_clusters, num_tensormaps=4, bytes_per_tensormap/8=16)
cute_ptr_of_tensor_of_tensormap = make_ptr(
cutlass.Int64, 0, cute.AddressSpace.gmem, assumed_align=16,
)
hardware_info = cutlass.utils.HardwareInfo()
max_active_clusters = hardware_info.get_max_active_clusters(
cluster_shape_mn[0] * cluster_shape_mn[1]
)
my_kernel = Sm100GroupedBlockScaledGemmKernel(
sf_vec_size,
mma_tiler_mn,
cluster_shape_mn,
)
num_groups = cutlass.Int32(len(problem_sizes))
try:
compiled_func = cute.compile(
my_kernel,
cute_ptr_of_tensor_of_problem_sizes,
cute_ptr_of_tensor_of_abc_ptrs,
cute_ptr_of_tensor_of_sfasfb_ptrs,
cute_ptr_of_tensor_of_tensormap,
total_num_clusters,
num_groups,
max_active_clusters
)
except Exception as e:
print(f"MLIR compilation failed: {e}")
print(f"Full traceback:")
import traceback
traceback.print_exc()
raise
# Store compiled kernel in cache with problem_sizes as key
_compiled_kernel_cache[cache_key] = compiled_func
return compiled_func
# Global context to persist GPU allocations and Pinned Memory across calls
# This eliminates cudaMalloc, cudaMemcpy, and python garbage collection overheads from the hot path.
_KERNEL_CONTEXT = {
"gpu_buffers": {}, # {name: torch.Tensor} (On Device)
"cpu_pinned": {}, # {name: torch.Tensor} (On Host, Pinned)
"cute_ptrs": {}, # {name: make_ptr(...)}
}
def custom_kernel(data: input_t) -> output_t:
abc_tensors, _, sfasfb_reordered_tensors, problem_sizes = data
compiled_func = compile_kernel(problem_sizes)
ctx = _KERNEL_CONTEXT
buffers = ctx["gpu_buffers"]
pinned = ctx["cpu_pinned"]
if buffers.get("combined") is None:
MAX_GROUPS = 8
MAX_CTAS = 1024
# Combined Buffer Layout (int64 elements):
# [0:3*MAX] -> ABC (3 pointers per group)
# [3*MAX:5*MAX] -> SF (2 pointers per group)
# [5*MAX:7*MAX] -> Sizes (4 int32s = 2 int64s per group)
total_int64 = 7 * MAX_GROUPS
# Single Unified Buffer (GPU + Pinned)
buffers["combined"] = torch.zeros(total_int64, dtype=torch.int64, device="cuda")
pinned["combined"] = torch.zeros(total_int64, dtype=torch.int64, pin_memory=True)
# Tensormap Buffer
tm_size = MAX_CTAS * Sm100GroupedBlockScaledGemmKernel.num_tensormaps * 16
buffers["tm"] = torch.empty(tm_size, dtype=torch.int64, device="cuda")
# Pre-calculate offsets (in bytes)
base_ptr = buffers["combined"].data_ptr()
idx_sf = MAX_GROUPS * 3
idx_sz = MAX_GROUPS * 5
# Pre-create CuTe pointers using the stable base address
ctx["cute_ptrs"]["abc"] = make_ptr(cutlass.Int64, base_ptr, cute.AddressSpace.gmem, assumed_align=16)
ctx["cute_ptrs"]["sf"] = make_ptr(cutlass.Int64, base_ptr + idx_sf * 8, cute.AddressSpace.gmem, assumed_align=16)
ctx["cute_ptrs"]["sizes"] = make_ptr(cutlass.Int32, base_ptr + idx_sz * 8, cute.AddressSpace.gmem, assumed_align=16)
ctx["cute_ptrs"]["tm"] = make_ptr(cutlass.Int64, buffers["tm"].data_ptr(), cute.AddressSpace.gmem, assumed_align=16)
ctx["offsets"] = (idx_sf, idx_sz)
# 1. Flatten Data for Copy
flat_sizes = [x for p in problem_sizes for x in p]
flat_abc = [p for (a,b,c) in abc_tensors for p in (a.data_ptr(), b.data_ptr(), c.data_ptr())]
flat_sf = [p for (sfa,sfb) in sfasfb_reordered_tensors for p in (sfa.data_ptr(), sfb.data_ptr())]
# 2. Update Pinned Memory (CPU side)
idx_sf, idx_sz = ctx["offsets"]
p_buf = pinned["combined"]
p_buf[:len(flat_abc)] = torch.tensor(flat_abc, dtype=torch.int64)
p_buf[idx_sf : idx_sf + len(flat_sf)] = torch.tensor(flat_sf, dtype=torch.int64)
# Cast to int32 for sizes (indices scale by 2 vs int64)
p_sizes = p_buf.view(torch.int32)
idx_sz_32 = idx_sz * 2
p_sizes[idx_sz_32 : idx_sz_32 + len(flat_sizes)] = torch.tensor(flat_sizes, dtype=torch.int32)
# 3. Async Copy to GPU (Single Call)
buffers["combined"].copy_(pinned["combined"], non_blocking=True)
_, n, k, _ = problem_sizes[0]
mma_tiler_mn, cluster_shape_mn, _, _ = config_map.get((n, k), ((128, 128), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_FIRST))
total_num_clusters = 0
for m, n, _, _ in problem_sizes:
# Calculate Tile Counts
tiles_m = (m + mma_tiler_mn[0] - 1) // mma_tiler_mn[0]
tiles_n = (n + mma_tiler_mn[1] - 1) // mma_tiler_mn[1]
clusters_m = (tiles_m + cluster_shape_mn[0] - 1) // cluster_shape_mn[0]
clusters_n = (tiles_n + cluster_shape_mn[1] - 1) // cluster_shape_mn[1]
total_num_clusters += clusters_m * clusters_n
compiled_func(
ctx["cute_ptrs"]["sizes"],
ctx["cute_ptrs"]["abc"],
ctx["cute_ptrs"]["sf"],
ctx["cute_ptrs"]["tm"],
cutlass.Int32(total_num_clusters)
)
# Return Result (Metadata construction only)
return [t[2] for t in abc_tensors]
scrolls · 2296 lines total
Source code from GPU Mode and the KernelBot dataset · June 9 Researcher Reciprocity License v1.0
Changes from previous submission
Against this author's previous submission submission 442449.
#!POPCORN leaderboard nvfp4_group_gemm- #!POPCORN gpu NVIDIA+ #!POPCORN gpu B200import cutlassimport cutlass.cute as cuteimport cutlass.utils as utils⋯ 3 unchanged linesimport cutlass.utils.blockscaled_layout as blockscaled_utilsfrom cutlass.cute.runtime import make_ptrfrom task import input_t, output_t- import functoolsfrom typing import List, Type, Tuple, Unionfrom inspect import isclassimport torchfrom cutlass.pipeline import pipeline_init_arrive, pipeline_init_wait- mma_tiler_mnk = (128, 128, 128)- cluster_shape_mn = (1, 1)ab_dtype = cutlass.Float4E2M1FNsf_dtype = cutlass.Float8E4M3FNc_dtype = cutlass.Float16sf_vec_size = 16+ _TMA_CACHE_EVICT_NORMAL = 0x1000000000000000+ _TMA_CACHE_EVICT_FIRST = 0x12F0000000000000+ _TMA_CACHE_EVICT_LAST = 0x14F0000000000000++ config_map = {+ (4096, 7168): ((128, 128), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_FIRST),+ (7168, 2048): ((128, 256), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_LAST),+ (3072, 4096): ((128, 128), (1, 4), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_LAST),+ (4096, 1536): ((128, 128), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_LAST),+ }+class Sm100GroupedBlockScaledGemmKernel:"""This example demonstrates an implementation of grouped blockscaled GEMM using a TMA plus Blackwell SM100 TensorCorewarp-specialized persistent kernel.⋯ 45 unchanged lines:param cluster_shape_mn: tuple (ClusterM, ClusterN) shape of the cluster.:type cluster_shape_mn: tuple[int, int]"""+ self.prefetch = True+ self.cache_policy = _TMA_CACHE_EVICT_LAST+self.acc_dtype = cutlass.Float32self.sf_vec_size = sf_vec_sizeself.use_2cta_instrs = mma_tiler_mn[0] == 256⋯ 583 unchanged lines"""warp_idx = cute.arch.warp_idx()warp_idx = cute.arch.make_warp_uniform(warp_idx)- if warp_idx == self.tma_warp_id:+ if warp_idx == self.tma_warp_id and self.prefetch:cute.nvgpu.cpasync.prefetch_descriptor(tma_atom_a)cute.nvgpu.cpasync.prefetch_descriptor(tma_atom_b)cute.nvgpu.cpasync.prefetch_descriptor(tma_atom_sfa)⋯ 445 unchanged linestensormap_a_gmem_ptr,cute.AddressSpace.generic,),+ cache_policy=cutlass.Int64(cutlass.Int64(self.cache_policy).ir_value()),)cute.copy(tma_atom_b,⋯ 5 unchanged linestensormap_b_gmem_ptr,cute.AddressSpace.generic,),+ cache_policy=cutlass.Int64(cutlass.Int64(self.cache_policy).ir_value()),)cute.copy(tma_atom_sfa,⋯ 5 unchanged linestensormap_sfa_gmem_ptr,cute.AddressSpace.generic,),+ cache_policy=cutlass.Int64(cutlass.Int64(self.cache_policy).ir_value()),)cute.copy(tma_atom_sfb,⋯ 5 unchanged linestensormap_sfb_gmem_ptr,cute.AddressSpace.generic,),+ cache_policy=cutlass.Int64(cutlass.Int64(self.cache_policy).ir_value()),)# Peek (try_wait) AB buffer empty for k_tile = prefetch_k_tile_cnt + k_tile + 1⋯ 974 unchanged linesThe compiled kernel function"""global _compiled_kernel_cache-+ _, n, k, _ = problem_sizes[0]# Convert problem_sizes list to a hashable tuple for use as dictionary key- cache_key = f"{len(problem_sizes)}"+ cache_key = f"{len(problem_sizes)}_{n}_{k}"# Check if we already have a compiled kernel for these problem sizesif cache_key in _compiled_kernel_cache:⋯ 9 unchanged linescutlass.Int64, 0, cute.AddressSpace.gmem, assumed_align=16,)+ mma_tiler_mn, cluster_shape_mn, _, _ = config_map.get((n, k), ((128, 128), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_FIRST))total_num_clusters = cutlass.Int32(1)num_groups = cutlass.Int32(len(problem_sizes))# Each cluster needs its own set of tensormaps (one for A, B, SFA, SFB)⋯ 9 unchanged linesmy_kernel = Sm100GroupedBlockScaledGemmKernel(sf_vec_size,- mma_tiler_mnk[:2],+ mma_tiler_mn,cluster_shape_mn,)⋯ 26 unchanged lines"gpu_buffers": {}, # {name: torch.Tensor} (On Device)"cpu_pinned": {}, # {name: torch.Tensor} (On Host, Pinned)"cute_ptrs": {}, # {name: make_ptr(...)}- "last_num_groups": -1, # To track if we need to resize}def custom_kernel(data: input_t) -> output_t:- """- Optimized custom kernel launch.- 1. Reuses pre-allocated GPU & Pinned CPU buffers (Flattened 1D).- 2. Uses async H2D copies to hide latency.- 3. Calculates strides on-device (removed from host).- """abc_tensors, _, sfasfb_reordered_tensors, problem_sizes = data- # 1. Compile (Cached by len(problem_sizes) internally)compiled_func = compile_kernel(problem_sizes)- total_num_clusters = 0- for m, n, _, _ in problem_sizes:- # equivalent to: ceil(m / 256) * ceil(n / 128)- total_num_clusters += ((m + mma_tiler_mnk[0] - 1) // mma_tiler_mnk[0]) * ((n + mma_tiler_mnk[1] - 1) // mma_tiler_mnk[1])ctx = _KERNEL_CONTEXTbuffers = ctx["gpu_buffers"]pinned = ctx["cpu_pinned"]- # Initialize ONCE with generous static limits (skips per-call resizing logic)- if buffers.get("abc") is None:- # Static Limits: Covers 4096 groups and 65k CTAs (sufficient for massive grids)- MAX_GROUPS = 4096- MAX_CTAS = 65536+ if buffers.get("combined") is None:+ MAX_GROUPS = 8+ MAX_CTAS = 1024- # GPU Buffers (1D)- buffers["abc"] = torch.zeros(MAX_GROUPS * 3, dtype=torch.int64, device="cuda")- buffers["sf"] = torch.zeros(MAX_GROUPS * 2, dtype=torch.int64, device="cuda")- buffers["sizes"] = torch.zeros(MAX_GROUPS * 4, dtype=torch.int32, device="cuda")+ # Combined Buffer Layout (int64 elements):+ # [0:3*MAX] -> ABC (3 pointers per group)+ # [3*MAX:5*MAX] -> SF (2 pointers per group)+ # [5*MAX:7*MAX] -> Sizes (4 int32s = 2 int64s per group)+ total_int64 = 7 * MAX_GROUPS+ # Single Unified Buffer (GPU + Pinned)+ buffers["combined"] = torch.zeros(total_int64, dtype=torch.int64, device="cuda")+ pinned["combined"] = torch.zeros(total_int64, dtype=torch.int64, pin_memory=True)+# Tensormap Buffertm_size = MAX_CTAS * Sm100GroupedBlockScaledGemmKernel.num_tensormaps * 16buffers["tm"] = torch.empty(tm_size, dtype=torch.int64, device="cuda")- # Pinned CPU Buffers (1D) - Essential for fast async copies- pinned["abc"] = torch.zeros(MAX_GROUPS * 3, dtype=torch.int64, pin_memory=True)- pinned["sf"] = torch.zeros(MAX_GROUPS * 2, dtype=torch.int64, pin_memory=True)- pinned["sizes"] = torch.zeros(MAX_GROUPS * 4, dtype=torch.int32, pin_memory=True)-+ # Pre-calculate offsets (in bytes)+ base_ptr = buffers["combined"].data_ptr()+ idx_sf = MAX_GROUPS * 3+ idx_sz = MAX_GROUPS * 5+# Pre-create CuTe pointers using the stable base address- ctx["cute_ptrs"]["abc"] = make_ptr(cutlass.Int64, buffers["abc"].data_ptr(), cute.AddressSpace.gmem, assumed_align=16)- ctx["cute_ptrs"]["sf"] = make_ptr(cutlass.Int64, buffers["sf"].data_ptr(), cute.AddressSpace.gmem, assumed_align=16)- ctx["cute_ptrs"]["sizes"] = make_ptr(cutlass.Int32, buffers["sizes"].data_ptr(), cute.AddressSpace.gmem, assumed_align=16)+ ctx["cute_ptrs"]["abc"] = make_ptr(cutlass.Int64, base_ptr, cute.AddressSpace.gmem, assumed_align=16)+ ctx["cute_ptrs"]["sf"] = make_ptr(cutlass.Int64, base_ptr + idx_sf * 8, cute.AddressSpace.gmem, assumed_align=16)+ ctx["cute_ptrs"]["sizes"] = make_ptr(cutlass.Int32, base_ptr + idx_sz * 8, cute.AddressSpace.gmem, assumed_align=16)ctx["cute_ptrs"]["tm"] = make_ptr(cutlass.Int64, buffers["tm"].data_ptr(), cute.AddressSpace.gmem, assumed_align=16)++ ctx["offsets"] = (idx_sf, idx_sz)# 1. Flatten Data for Copy- # List comprehensions are faster than loops with .appendflat_sizes = [x for p in problem_sizes for x in p]flat_abc = [p for (a,b,c) in abc_tensors for p in (a.data_ptr(), b.data_ptr(), c.data_ptr())]flat_sf = [p for (sfa,sfb) in sfasfb_reordered_tensors for p in (sfa.data_ptr(), sfb.data_ptr())]# 2. Update Pinned Memory (CPU side)- # Using 1D slice assignment avoids "size mismatch" errors- # creating torch.tensor from list is fast for these sizes (~2us)- pinned["sizes"][:len(flat_sizes)] = torch.tensor(flat_sizes, dtype=torch.int32)- pinned["abc"][:len(flat_abc)] = torch.tensor(flat_abc, dtype=torch.int64)- pinned["sf"][:len(flat_sf)] = torch.tensor(flat_sf, dtype=torch.int64)+ idx_sf, idx_sz = ctx["offsets"]+ p_buf = pinned["combined"]++ p_buf[:len(flat_abc)] = torch.tensor(flat_abc, dtype=torch.int64)+ p_buf[idx_sf : idx_sf + len(flat_sf)] = torch.tensor(flat_sf, dtype=torch.int64)- # 3. Async Copy to GPU- # The copy engine runs in parallel with Python execution- buffers["sizes"][:len(flat_sizes)].copy_(pinned["sizes"][:len(flat_sizes)], non_blocking=True)- buffers["abc"][:len(flat_abc)].copy_(pinned["abc"][:len(flat_abc)], non_blocking=True)- buffers["sf"][:len(flat_sf)].copy_(pinned["sf"][:len(flat_sf)], non_blocking=True)+ # Cast to int32 for sizes (indices scale by 2 vs int64)+ p_sizes = p_buf.view(torch.int32)+ idx_sz_32 = idx_sz * 2+ p_sizes[idx_sz_32 : idx_sz_32 + len(flat_sizes)] = torch.tensor(flat_sizes, dtype=torch.int32)- # --- STEP 4: Launch ----- # Use cached cute pointers (their .data_ptr() is constant)- # Passed arguments: sizes_ptr, abc_ptrs_ptr, sf_ptrs_ptr, tm_ptr, strides_ptr(REMOVED), total_clusters+ # 3. Async Copy to GPU (Single Call)+ buffers["combined"].copy_(pinned["combined"], non_blocking=True)++ _, n, k, _ = problem_sizes[0]+ mma_tiler_mn, cluster_shape_mn, _, _ = config_map.get((n, k), ((128, 128), (1, 1), _TMA_CACHE_EVICT_LAST, _TMA_CACHE_EVICT_FIRST))+ total_num_clusters = 0+ for m, n, _, _ in problem_sizes:+ # Calculate Tile Counts+ tiles_m = (m + mma_tiler_mn[0] - 1) // mma_tiler_mn[0]+ tiles_n = (n + mma_tiler_mn[1] - 1) // mma_tiler_mn[1]++ clusters_m = (tiles_m + cluster_shape_mn[0] - 1) // cluster_shape_mn[0]+ clusters_n = (tiles_n + cluster_shape_mn[1] - 1) // cluster_shape_mn[1]++ total_num_clusters += clusters_m * clusters_ncompiled_func(ctx["cute_ptrs"]["sizes"],ctx["cute_ptrs"]["abc"],ctx["cute_ptrs"]["sf"],ctx["cute_ptrs"]["tm"],- # Note: We removed the stride tensor argument based on previous optimizationcutlass.Int32(total_num_clusters))
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