cutlass/include/cutlass/epilogue/threadblock/epilogue_with_visitor_callbacks.h
2024-01-16 14:37:22 -05:00

505 lines
17 KiB
C++

/***************************************************************************************************
* Copyright (c) 2023 - 2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
**************************************************************************************************/
/*! \file
\brief Functor performing elementwise operations used by epilogues.
*/
#pragma once
/////////////////////////////////////////////////////////////////////////////////////////////////
#include "cutlass/epilogue/threadblock/epilogue_base.h"
////////////////////////////////////////////////////////////////////////////////////////////////////
namespace cutlass {
namespace epilogue {
namespace threadblock {
namespace detail {
struct EVT2xBase { };
template <class T>
static constexpr bool is_2x_evt_v = platform::is_base_of<EVT2xBase, T>::value;
} // namespace detail
////////////////////////////////////////////////////////////////////////////////////////////////////
/// Epilogue operator
template <
typename DefaultEpilogue, ///< Default Epilogue Descriptor
typename FusionCallbacks_, ///< The called fusion callbacks
int Stages = 2, ///< Software pipeline stages for epilogue
int IterationsUnroll = true ///< Used to reduce binary size when epilogue op is large
>
class EpilogueWithVisitorCallbacks :
public EpilogueBase<
typename DefaultEpilogue::Shape,
typename DefaultEpilogue::WarpMmaOperator::Shape,
DefaultEpilogue::kPartitionsK,
typename DefaultEpilogue::AccumulatorFragmentIterator,
typename DefaultEpilogue::WarpTileIterator,
typename DefaultEpilogue::Padding,
DefaultEpilogue::kFragmentsPerIteration>,
public EpilogueBaseStreamK<
typename DefaultEpilogue::Shape,
DefaultEpilogue::kPartitionsK,
typename DefaultEpilogue::WarpMmaOperator,
typename DefaultEpilogue::AccumulatorFragmentIterator>,
public detail::EVT2xBase
{
public:
static_assert(Stages <= 2, "Sm80 EVT only support upto 2 Stages.");
// Whether the epilogue is pipelined
static bool constexpr Pipelined = Stages > 1;
using FusionCallbacks = FusionCallbacks_;
using OutputTileIterator = typename DefaultEpilogue::OutputTileIterator;
// Number of epilogue iterations.
// Each iteration processes a 8xThreadblockTile::kN output tile
static const int kIterations = OutputTileIterator::kIterations;
using Base = EpilogueBase<
typename DefaultEpilogue::Shape,
typename DefaultEpilogue::WarpMmaOperator::Shape,
DefaultEpilogue::kPartitionsK,
typename DefaultEpilogue::AccumulatorFragmentIterator,
typename DefaultEpilogue::WarpTileIterator,
typename DefaultEpilogue::Padding,
DefaultEpilogue::kFragmentsPerIteration>;
using BaseStreamK = EpilogueBaseStreamK<
typename DefaultEpilogue::Shape,
DefaultEpilogue::kPartitionsK,
typename DefaultEpilogue::WarpMmaOperator,
typename DefaultEpilogue::AccumulatorFragmentIterator>;
static int const kPartitionsK = DefaultEpilogue::kPartitionsK;
using AccumulatorFragmentIterator = typename DefaultEpilogue::AccumulatorFragmentIterator;
using WarpTileIterator = typename DefaultEpilogue::WarpTileIterator;
using SharedLoadIterator = typename DefaultEpilogue::SharedLoadIterator;
/// The complete warp-level accumulator tile
using AccumulatorTile = typename Base::AccumulatorTile;
/// Accumulator element
using ElementAccumulator = typename WarpTileIterator::Element;
struct OutputOp{
using ElementAccumulator = ElementAccumulator;
using Params = typename FusionCallbacks::Arguments;
};
/// Fragment type used by the accumulator tile's fragment iterator
using AccumulatorFragment = typename AccumulatorFragmentIterator::Fragment;
// Output access size
static int const kElementsPerAccess = DefaultEpilogue::kElementsPerAccess;
/// Array type used by output functor
using AccumulatorAccessType = Array<
typename WarpTileIterator::Element, kElementsPerAccess>;
static int constexpr kSmemTiles = Base::kFragmentsPerIteration > 1 ? Base::kFragmentsPerIteration : kPartitionsK;
static int constexpr kSmemPointerOffset = Base::SharedStorage::StorageShape::kCount / kSmemTiles;
using Params = typename FusionCallbacks::Params;
static size_t constexpr kSmemStageOffset = sizeof(Base::SharedStorage) / sizeof(ElementAccumulator);
static int constexpr kAccumulatorFragmentCount = AccumulatorTile::kElements / (kIterations * AccumulatorAccessType::kElements) / kPartitionsK;
struct SharedStorage {
typename Base::SharedStorage acc_smem[Stages];
typename FusionCallbacks::SharedStorage callback_smem;
};
private:
/// Loads fragment from shared memory aligned with output tensor
SharedLoadIterator shared_load_iterator_;
FusionCallbacks fusion_callbacks;
public:
/// Constructor
CUTLASS_DEVICE
EpilogueWithVisitorCallbacks(
const Params &params_callbacks, ///< Epilogue Visitor params
SharedStorage &shared_storage, ///< Shared storage object
int thread_idx, ///< ID of a thread within the threadblock
int warp_idx, ///< ID of warp within threadblock
int lane_idx ///< Id of thread within warp
):
Base(shared_storage.acc_smem[0], thread_idx, warp_idx, lane_idx),
BaseStreamK(thread_idx),
shared_load_iterator_(shared_storage.acc_smem[0].reference(), thread_idx),
fusion_callbacks(params_callbacks, shared_storage.callback_smem)
{ }
/// Aggregates the accumulator sets shared by peer blocks in the global workspace,
/// performing epilogue computations, writing to output
template <class ProblemShape>
CUTLASS_DEVICE
void reduce(
int peer_idx_begin,
int peer_idx_end,
int reduce_fragment_idx,
void *element_workspace,
cutlass::gemm::GemmCoord threadblock_tile_offset,
ProblemShape problem_shape,
int thread_idx)
{
auto callbacks = fusion_callbacks.get_callbacks(
threadblock_tile_offset,
thread_idx,
problem_shape
);
callbacks.begin_epilogue();
// Reduce peer accumulator fragments into one fragment
AccumulatorFragment accum_fragment;
BaseStreamK::reduce(accum_fragment, peer_idx_begin, peer_idx_end, reduce_fragment_idx, element_workspace);
// Store fragment to shared memory
this->warp_tile_iterator_.store(accum_fragment);
__syncthreads();
callbacks.begin_step(reduce_fragment_idx);
// Load fragment from shared memory
typename SharedLoadIterator::Fragment aligned_accum_fragment;
shared_load_iterator_.load(aligned_accum_fragment);
// Add fragments shared by other k partitions
if (kPartitionsK > 1)
{
plus <typename SharedLoadIterator::Fragment> add_fragments;
CUTLASS_PRAGMA_UNROLL
for ( int i = 1; i < kPartitionsK; ++i) {
typename SharedLoadIterator::Fragment aligned_addend_fragment;
shared_load_iterator_.add_pointer_offset(kSmemPointerOffset);
shared_load_iterator_.load(aligned_addend_fragment);
aligned_accum_fragment = add_fragments(aligned_accum_fragment, aligned_addend_fragment);
}
}
//
// Iterate over output fragment
//
AccumulatorAccessType const *accum_frag_ptr =
reinterpret_cast<AccumulatorAccessType const*>(&aligned_accum_fragment);
CUTLASS_PRAGMA_UNROLL
for (int idx = 0; idx < kAccumulatorFragmentCount; ++idx) {
int row_idx = idx / SharedLoadIterator::ThreadMap::Iterations::kColumn;
int col_idx = idx % SharedLoadIterator::ThreadMap::Iterations::kColumn;
// Start a new row of the output fragment
if (!col_idx) {
callbacks.begin_row(row_idx);
}
callbacks.visit(
reduce_fragment_idx,
row_idx,
col_idx,
idx,
accum_frag_ptr[idx]
);
// End the row of the output fragment
if (col_idx + 1 == SharedLoadIterator::ThreadMap::Iterations::kColumn) {
callbacks.end_row(row_idx);
}
}
callbacks.end_step(reduce_fragment_idx);
callbacks.end_epilogue();
}
/// Streams the result to global memory
template <class ProblemShape>
CUTLASS_DEVICE
void operator()(
AccumulatorTile const &accumulators,
cutlass::gemm::GemmCoord threadblock_tile_offset,
ProblemShape problem_shape,
int thread_idx
) { ///< Threadblock tile coordinate in GEMM (in units of threadblock tiles)
auto callbacks = fusion_callbacks.get_callbacks(
threadblock_tile_offset,
thread_idx,
problem_shape
);
callbacks.begin_epilogue();
//
// Iterator over warp-level accumulator fragment
//
AccumulatorFragmentIterator accum_fragment_iterator(accumulators);
//
// Iterate over accumulator tile
//
if constexpr(Pipelined){
__syncthreads();
//
// Pipeline Prologue
//
size_t warp_iterator_offset = kSmemStageOffset;
size_t smem_iterator_offset = kSmemStageOffset;
callbacks.begin_step(0);
acc2smem_source_needed<cutlass::make_index_sequence<kIterations>>::push(
0, accum_fragment_iterator, this->warp_tile_iterator_);
this->warp_tile_iterator_.add_pointer_offset(warp_iterator_offset);
warp_iterator_offset = -warp_iterator_offset;
//
// Pipeline Loop
//
#pragma unroll(IterationsUnroll ? kIterations : 1)
for (int iter_idx = 1; iter_idx < kIterations + 1; ++iter_idx) {
__syncthreads();
// Skip the load for epilogue
if (iter_idx < kIterations) {
callbacks.begin_step(iter_idx);
acc2smem_source_needed<cutlass::make_index_sequence<kIterations>>::push(
iter_idx, accum_fragment_iterator, this->warp_tile_iterator_);
this->warp_tile_iterator_.add_pointer_offset(warp_iterator_offset);
warp_iterator_offset = -warp_iterator_offset;
}
typename SharedLoadIterator::Fragment aligned_accum_fragment[kPartitionsK];
shared_load_iterator_.load(aligned_accum_fragment[0]);
// If the number of k-slices is > 1 - perform a reduction amongst the k-slices
if (kPartitionsK > 1) {
plus <typename SharedLoadIterator::Fragment> add_fragments;
CUTLASS_PRAGMA_UNROLL
for ( int i = 1; i < kPartitionsK; ++i) {
shared_load_iterator_.add_pointer_offset(kSmemPointerOffset);
shared_load_iterator_.load(aligned_accum_fragment[i]);
aligned_accum_fragment[0] = add_fragments(aligned_accum_fragment[0], aligned_accum_fragment[i]);
}
shared_load_iterator_.add_pointer_offset((1 - kPartitionsK) * kSmemPointerOffset);
}
shared_load_iterator_.add_pointer_offset(smem_iterator_offset);
smem_iterator_offset = -smem_iterator_offset;
//
// Iterate over output fragments
//
AccumulatorAccessType const *accum_frag_ptr =
reinterpret_cast<AccumulatorAccessType const *>(&aligned_accum_fragment);
CUTLASS_PRAGMA_UNROLL
for (int idx = 0; idx < kAccumulatorFragmentCount; ++idx) {
int row_idx = idx / SharedLoadIterator::ThreadMap::Iterations::kColumn;
int col_idx = idx % SharedLoadIterator::ThreadMap::Iterations::kColumn;
// Start a new row of the output fragment
if (!col_idx) {
callbacks.begin_row(row_idx);
}
callbacks.visit(
iter_idx-1,
row_idx,
col_idx,
idx,
accum_frag_ptr[idx]
);
// End the row of the output fragment
if (col_idx + 1 == SharedLoadIterator::ThreadMap::Iterations::kColumn) {
callbacks.end_row(row_idx);
}
}
//
// Conclude the step
//
callbacks.end_step(iter_idx-1);
}
} else {
#pragma unroll(IterationsUnroll ? kIterations : 1)
for (int iter_idx = 0; iter_idx < kIterations; ++iter_idx) {
//
// Load the source
//
callbacks.begin_step(iter_idx);
//
// Convert and store fragment
//
__syncthreads();
acc2smem_source_needed<cutlass::make_index_sequence<kIterations>>::push(
iter_idx, accum_fragment_iterator, this->warp_tile_iterator_);
__syncthreads();
//
// Load fragments from shared memory
//
typename SharedLoadIterator::Fragment aligned_accum_fragment[kPartitionsK];
shared_load_iterator_.load(aligned_accum_fragment[0]);
// If the number of k-slices is > 1 - perform a reduction amongst the k-slices
if (kPartitionsK > 1) {
plus <typename SharedLoadIterator::Fragment> add_fragments;
CUTLASS_PRAGMA_UNROLL
for ( int i = 1; i < kPartitionsK; ++i) {
shared_load_iterator_.add_pointer_offset(kSmemPointerOffset);
shared_load_iterator_.load(aligned_accum_fragment[i]);
aligned_accum_fragment[0] = add_fragments(aligned_accum_fragment[0], aligned_accum_fragment[i]);
}
shared_load_iterator_.add_pointer_offset((1 - kPartitionsK) * kSmemPointerOffset);
}
//
// Iterate over output fragments
//
AccumulatorAccessType const *accum_frag_ptr =
reinterpret_cast<AccumulatorAccessType const *>(&aligned_accum_fragment[0]);
CUTLASS_PRAGMA_UNROLL
for (int idx = 0; idx < kAccumulatorFragmentCount; ++idx) {
int row_idx = idx / SharedLoadIterator::ThreadMap::Iterations::kColumn;
int col_idx = idx % SharedLoadIterator::ThreadMap::Iterations::kColumn;
// Start a new row of the output fragment
if (!col_idx) {
callbacks.begin_row(row_idx);
}
callbacks.visit(
iter_idx,
row_idx,
col_idx,
idx,
accum_frag_ptr[idx]
);
// End the row of the output fragment
if (col_idx + 1 == SharedLoadIterator::ThreadMap::Iterations::kColumn) {
callbacks.end_row(row_idx);
}
}
//
// Conclude the step
//
callbacks.end_step(iter_idx);
}
}
callbacks.end_epilogue();
}
private:
template<class Seq>
struct acc2smem_source_needed;
template <size_t... Seq>
struct acc2smem_source_needed<cutlass::index_sequence<Seq...>> {
template<int Advance>
CUTLASS_DEVICE
static void helper(AccumulatorFragmentIterator accum_fragment_iterator,
WarpTileIterator &warp_tile_iterator) {
CUTLASS_PRAGMA_UNROLL
for (int i = 0; i < Advance; i++) {
++accum_fragment_iterator;
}
typename AccumulatorFragmentIterator::Fragment accum_fragment;
accum_fragment_iterator.load(accum_fragment);
warp_tile_iterator.store(accum_fragment);
}
CUTLASS_DEVICE
static void push(size_t pos,
AccumulatorFragmentIterator const &iterator_begin,
WarpTileIterator &warp_tile_iterator) {
int dummy[] = {(pos == Seq) && (helper<Seq>(iterator_begin, warp_tile_iterator), 0)...};
}
};
};
/////////////////////////////////////////////////////////////////////////////////////////////////
} // namespace threadblock
} // namespace epilogue
} // namespace cutlass
/////////////////////////////////////////////////////////////////////////////////////////////////