
Requires a recent clang build (r359248 or newer). Enable compilation with clang with these options: cmake -DCUDA_COMPILER=clang -DCMAKE_CXX_COMPILER=/path/to/clang++
275 lines
10 KiB
C++
275 lines
10 KiB
C++
/***************************************************************************************************
|
|
* Copyright (c) 2017-2019, NVIDIA CORPORATION. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without modification, are permitted
|
|
* provided that the following conditions are met:
|
|
* * Redistributions of source code must retain the above copyright notice, this list of
|
|
* conditions and the following disclaimer.
|
|
* * 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.
|
|
* * Neither the name of the NVIDIA CORPORATION 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 NVIDIA CORPORATION 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 TOR (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 Implements a software-pipelined efficient GEMM.
|
|
*/
|
|
#pragma once
|
|
|
|
#include "cutlass/cutlass.h"
|
|
#include "cutlass/coord.h"
|
|
|
|
namespace cutlass {
|
|
namespace gemm {
|
|
|
|
/////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
|
template <typename Traits_>
|
|
struct GemmMainloop {
|
|
|
|
//
|
|
// Type definitions
|
|
//
|
|
|
|
/// The traits.
|
|
typedef Traits_ Traits;
|
|
|
|
/// The GEMM mainloop
|
|
typedef typename Traits::KernelClass KernelClass;
|
|
|
|
/// The shared storage.
|
|
typedef typename Traits::SharedStorage SharedStorage;
|
|
|
|
/// The scalar for A.
|
|
typedef typename Traits::ScalarA ScalarA;
|
|
/// The scalar for B.
|
|
typedef typename Traits::ScalarB ScalarB;
|
|
/// The scalar in the epilogue.
|
|
typedef typename Traits::Epilogue::Scalar ScalarEpilogue;
|
|
/// The scalar for C.
|
|
typedef typename Traits::Epilogue::ScalarC ScalarC;
|
|
/// The scalar for D.
|
|
typedef typename Traits::Epilogue::ScalarD ScalarD;
|
|
/// The index.
|
|
typedef typename Traits::Index Index;
|
|
|
|
/// Define the mainloop iteration size
|
|
typedef typename Traits::MultiplyAdd MultiplyAdd;
|
|
|
|
/// The number of threads.
|
|
static int const kThreads = Traits::GemmConfig::kThreads;
|
|
|
|
// Number of warp-level multiply-accumulate steps executed by each warp.
|
|
static Index const kWarpGemmSteps =
|
|
Traits::GemmConfig::AccumulatorsPerWarp::kD / MultiplyAdd::InstructionShape::kD;
|
|
|
|
/*
|
|
// Make sure we have at least 2 unrolling steps or our pipeling is not going to work.
|
|
static_assert(kWarpGemmSteps >= 2, "The pipelining assumes at least two steps");
|
|
*/
|
|
|
|
/// Use the params object defined in traits
|
|
typedef typename Traits::Params Params;
|
|
|
|
//
|
|
// Data members
|
|
//
|
|
|
|
/// The params.
|
|
Params const& params;
|
|
|
|
/// SharedStorage object
|
|
SharedStorage& shared_storage;
|
|
|
|
//
|
|
// Methods
|
|
//
|
|
|
|
/// Ctor.
|
|
CUTLASS_DEVICE GemmMainloop(Params const& params_, SharedStorage& shared_storage_)
|
|
: params(params_), shared_storage(shared_storage_) {}
|
|
|
|
/// Fetches global stream pair
|
|
template <bool Residue>
|
|
CUTLASS_DEVICE void fetch_global(typename Traits::GlobalLoadStream& global_to_shared_stream,
|
|
Index outer_k) {
|
|
// If residue portion and not calculating residue in prolog, update residue predicates now.
|
|
if (Residue) {
|
|
global_to_shared_stream.residue(outer_k);
|
|
}
|
|
global_to_shared_stream.copy();
|
|
}
|
|
|
|
/// Computes a warp-level GEMM on data held in shared memory
|
|
template <bool Residue, bool LastIteration>
|
|
CUTLASS_DEVICE void consume_tile(typename Traits::GlobalLoadStream& global_to_shared_stream,
|
|
typename Traits::SharedStream& shared_load_stream,
|
|
typename MultiplyAdd::Accumulators& accumulators,
|
|
Index outer_k) {
|
|
|
|
// Whether to load global stream before loading shared stream
|
|
const bool kGlobalStreamFirst = (kWarpGemmSteps <= 4);
|
|
|
|
// Load data for the next iteration of the main loop (unless it's the last iteration).
|
|
if (kGlobalStreamFirst && !LastIteration) {
|
|
fetch_global<Residue>(global_to_shared_stream, outer_k);
|
|
}
|
|
|
|
CUTLASS_PRAGMA_UNROLL
|
|
for (int step = 0; step < kWarpGemmSteps; ++step) {
|
|
|
|
// Trigger the copy from shared memory for the next A/B values.
|
|
shared_load_stream.copy((step + 1) % kWarpGemmSteps);
|
|
|
|
// Load data for the next iteration of the main loop (unless it's the last iteration).
|
|
if (!kGlobalStreamFirst && (step == 0) && !LastIteration) {
|
|
fetch_global<Residue>(global_to_shared_stream, outer_k);
|
|
}
|
|
|
|
if (step == kWarpGemmSteps - 2) {
|
|
// Make sure the data from shared memory has been entirely consumed.
|
|
Traits::shared_load_fence(true);
|
|
|
|
global_to_shared_stream.commit();
|
|
|
|
// Make sure the data is in shared memory.
|
|
Traits::shared_store_fence(true);
|
|
|
|
// Move to the next stage for the load (if it makes sense).
|
|
shared_load_stream.inc_stage();
|
|
}
|
|
|
|
// Make sure the values are available for the current iteration to do the multiply-add.
|
|
shared_load_stream.commit(step);
|
|
|
|
// Do the math on the fragments of the current iteration.
|
|
MultiplyAdd multiply_add;
|
|
multiply_add.multiply_add(shared_load_stream.fragment_a(step),
|
|
shared_load_stream.fragment_b(step),
|
|
accumulators,
|
|
accumulators);
|
|
}
|
|
}
|
|
|
|
/// Do the GEMM.
|
|
CUTLASS_DEVICE void multiply_add() {
|
|
// Swizzle the IDs of the block (to enable better cache behavior).
|
|
typename Traits::BlockSwizzle block_swizzle;
|
|
Coord<3> threadblock_offset =
|
|
block_swizzle.get_threadblock_offset(make_Coord_from_shape<typename Traits::OutputTile>());
|
|
|
|
// We may want to use shared memory to clear the registers.
|
|
typedef typename Traits::ClearAccumulators ClearAccumulators;
|
|
|
|
// Get the bounds for each thread, it maybe different than problem_size
|
|
Coord<3> bounds = block_swizzle.get_threadblock_bounds(params.problem_size,
|
|
params.partitionK_range);
|
|
|
|
// The streams to read A/B from global memory to shared memory.
|
|
typename Traits::GlobalLoadStream global_to_shared_stream(
|
|
params.global_to_shared_stream,
|
|
shared_storage.main_loop.global_to_shared_stream,
|
|
shared_storage.main_loop.threadblock_tile.reference(),
|
|
bounds,
|
|
threadblock_offset);
|
|
|
|
// update A and B pointer offset based on batch_id and batch_stride_offset
|
|
global_to_shared_stream.add_batch_offset(block_swizzle.get_batch_id());
|
|
|
|
// Create the accumulator clear.
|
|
ClearAccumulators clear;
|
|
|
|
// Deal with residue in prolog.
|
|
// global_to_shared_stream.move_to_residue(params.problem_size[0], Traits::OutputTile::kD);
|
|
global_to_shared_stream.move_to_residue(bounds[0], Traits::OutputTile::kD);
|
|
|
|
// Fetch the fragments for A and B from global memory.
|
|
global_to_shared_stream.copy();
|
|
|
|
// Copy the elements to shared memory (after transformation if needed).
|
|
global_to_shared_stream.commit();
|
|
|
|
// Make sure the data is in shared memory.
|
|
Traits::shared_store_fence(false);
|
|
|
|
// Rollback to the beginning of the first tile (if residue exists).
|
|
// global_to_shared_stream.rollback(params.problem_size[0] % Traits::OutputTile::kD);
|
|
global_to_shared_stream.rollback(bounds[0] % Traits::OutputTile::kD);
|
|
|
|
// The stream of data from shared memory to fragments.
|
|
typename Traits::SharedStream shared_load_stream(
|
|
params.shared_stream,
|
|
shared_storage.main_loop.threadblock_tile.reference());
|
|
|
|
// Trigger the copy from shared memory for the 1st stream.
|
|
shared_load_stream.copy(0);
|
|
|
|
// Allocate the accumulators.
|
|
typename MultiplyAdd::Accumulators accumulators;
|
|
|
|
// Clear the accumulators.
|
|
clear.clear(accumulators);
|
|
|
|
// Initial index
|
|
// Index outer_k = params.problem_size[0] - Traits::OutputTile::kD;
|
|
// problem_size[0] might be bigger than bounds[0]
|
|
Index outer_k = bounds[0] - Traits::OutputTile::kD;
|
|
// Check if we are computing residue in prolog or not.
|
|
if (Traits::GemmConfig::kResidueInProlog) {
|
|
// Execute all mainloop iterations but the last one.
|
|
|
|
CUTLASS_GEMM_LOOP
|
|
for (; outer_k > 0; outer_k -= Traits::OutputTile::kD) {
|
|
CUTLASS_GEMM_LOOP_HEADER
|
|
consume_tile<false, false>(
|
|
global_to_shared_stream, shared_load_stream, accumulators, outer_k);
|
|
}
|
|
|
|
consume_tile<false, true>(
|
|
global_to_shared_stream, shared_load_stream, accumulators, outer_k);
|
|
|
|
} else {
|
|
// When kResidueSeparate = true, execute all mainloop iterations but the last two without any
|
|
// consideration for K-residue or predicate updates. This improves the steady state of some
|
|
// kernels.
|
|
if (Traits::GemmConfig::kResidueSeparate) {
|
|
|
|
CUTLASS_GEMM_LOOP
|
|
for (; outer_k > Traits::OutputTile::kD; outer_k -= Traits::OutputTile::kD) {
|
|
CUTLASS_GEMM_LOOP_HEADER
|
|
consume_tile<false, false>(
|
|
global_to_shared_stream, shared_load_stream, accumulators, outer_k);
|
|
}
|
|
}
|
|
|
|
// Execute remaining tiles with K-residue predicate updates enabled.
|
|
CUTLASS_GEMM_LOOP
|
|
for (; outer_k > -Traits::OutputTile::kD; outer_k -= Traits::OutputTile::kD) {
|
|
CUTLASS_GEMM_LOOP_HEADER
|
|
consume_tile<true, false>(
|
|
global_to_shared_stream, shared_load_stream, accumulators, outer_k);
|
|
}
|
|
}
|
|
|
|
typedef typename Traits::Epilogue Epilogue;
|
|
Epilogue epilogue(params.epilogue, shared_storage.epilogue, params.problem_size.knm());
|
|
epilogue.epilogue(accumulators, threadblock_offset, block_swizzle.get_batch_id());
|
|
}
|
|
};
|
|
|
|
/////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
|
} // namespace gemm
|
|
} // namespace cutlass
|