Clean up kernels and drop unneeded modifications

This commit is contained in:
Thomas Gibson 2022-05-31 11:29:42 -05:00
parent a075455ad4
commit bcf8708f2c
3 changed files with 53 additions and 153 deletions

View File

@ -10,31 +10,6 @@
#define TBSIZE 1024 #define TBSIZE 1024
#ifdef NONTEMPORAL
template<typename T>
__device__ __forceinline__ T load(const T& ref)
{
return __builtin_nontemporal_load(&ref);
}
template<typename T>
__device__ __forceinline__ void store(const T& value, T& ref)
{
__builtin_nontemporal_store(value, &ref);
}
#else
template<typename T>
__device__ __forceinline__ T load(const T& ref)
{
return ref;
}
template<typename T>
__device__ __forceinline__ void store(const T& value, T& ref)
{
ref = value;
}
#endif
void check_error(void) void check_error(void)
{ {
@ -49,27 +24,23 @@ void check_error(void)
template <class T> template <class T>
HIPStream<T>::HIPStream(const int ARRAY_SIZE, const int device_index) HIPStream<T>::HIPStream(const int ARRAY_SIZE, const int device_index)
: array_size{ARRAY_SIZE}, : array_size{ARRAY_SIZE},
block_count(array_size / (TBSIZE * elements_per_lane * chunks_per_block)) block_count(array_size / (TBSIZE * elements_per_lane))
{ {
std::cerr << "Elements per lane: " << elements_per_lane << std::endl; std::cerr << "Elements per lane: " << elements_per_lane << std::endl;
std::cerr << "Chunks per block: " << chunks_per_block << std::endl; std::cerr << "Chunks per block: " << chunks_per_block << std::endl;
// The array size must be divisible by total number of elements // The array size must be divisible by total number of elements
// moved per block for kernel launches // moved per block for kernel launches
if (ARRAY_SIZE % (TBSIZE * elements_per_lane * chunks_per_block) != 0) if (ARRAY_SIZE % (TBSIZE * elements_per_lane) != 0)
{ {
std::stringstream ss; std::stringstream ss;
ss << "Array size must be a multiple of elements operated on per block (" ss << "Array size must be a multiple of elements operated on per block ("
<< TBSIZE * elements_per_lane * chunks_per_block << TBSIZE * elements_per_lane
<< ")."; << ").";
throw std::runtime_error(ss.str()); throw std::runtime_error(ss.str());
} }
std::cerr << "block count " << block_count << std::endl; std::cerr << "block count " << block_count << std::endl;
#ifdef NONTEMPORAL
std::cerr << "Using non-temporal memory operations." << std::endl;
#endif
// Set device // Set device
int count; int count;
hipGetDeviceCount(&count); hipGetDeviceCount(&count);
@ -86,7 +57,8 @@ HIPStream<T>::HIPStream(const int ARRAY_SIZE, const int device_index)
array_size = ARRAY_SIZE; array_size = ARRAY_SIZE;
// Allocate the host array for partial sums for dot kernels // Allocate the host array for partial sums for dot kernels
sums = (T*)malloc(block_count*sizeof(T)); hipHostMalloc(&sums, sizeof(T) * block_count, hipHostMallocNonCoherent);
check_error();
// Check buffers fit on the device // Check buffers fit on the device
hipDeviceProp_t props; hipDeviceProp_t props;
@ -101,15 +73,14 @@ HIPStream<T>::HIPStream(const int ARRAY_SIZE, const int device_index)
check_error(); check_error();
hipMalloc(&d_c, ARRAY_SIZE*sizeof(T)); hipMalloc(&d_c, ARRAY_SIZE*sizeof(T));
check_error(); check_error();
hipMalloc(&d_sum, block_count*sizeof(T));
check_error();
} }
template <class T> template <class T>
HIPStream<T>::~HIPStream() HIPStream<T>::~HIPStream()
{ {
free(sums); hipHostFree(sums);
check_error();
hipFree(d_a); hipFree(d_a);
check_error(); check_error();
@ -117,15 +88,13 @@ HIPStream<T>::~HIPStream()
check_error(); check_error();
hipFree(d_c); hipFree(d_c);
check_error(); check_error();
hipFree(d_sum);
check_error();
} }
template <typename T> template <typename T>
__global__ void init_kernel(T * a, T * b, T * c, T initA, T initB, T initC) __global__ void init_kernel(T * a, T * b, T * c, T initA, T initB, T initC)
{ {
const int i = hipBlockDim_x * hipBlockIdx_x + hipThreadIdx_x; const size_t i = blockDim.x * blockIdx.x + threadIdx.x;
a[i] = initA; a[i] = initA;
b[i] = initB; b[i] = initB;
c[i] = initC; c[i] = initC;
@ -152,26 +121,20 @@ void HIPStream<T>::read_arrays(std::vector<T>& a, std::vector<T>& b, std::vector
check_error(); check_error();
} }
template <size_t elements_per_lane, size_t chunks_per_block, typename T> template <size_t elements_per_lane, typename T>
__launch_bounds__(TBSIZE) __launch_bounds__(TBSIZE)
__global__ __global__
void copy_kernel(const T * __restrict a, T * __restrict c) void copy_kernel(const T * __restrict a, T * __restrict c)
{ {
const size_t dx = (blockDim.x * gridDim.x) * elements_per_lane;
const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane; const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane;
for (size_t i = 0; i != chunks_per_block; ++i) for (size_t j = 0; j < elements_per_lane; ++j)
{ c[gidx + j] = a[gidx + j];
for (size_t j = 0; j != elements_per_lane; ++j)
{
store(load(a[gidx + i * dx + j]), c[gidx + i * dx + j]);
}
}
} }
template <class T> template <class T>
void HIPStream<T>::copy() void HIPStream<T>::copy()
{ {
hipLaunchKernelGGL(HIP_KERNEL_NAME(copy_kernel<elements_per_lane, chunks_per_block, T>), hipLaunchKernelGGL(HIP_KERNEL_NAME(copy_kernel<elements_per_lane, T>),
dim3(block_count), dim3(block_count),
dim3(TBSIZE), dim3(TBSIZE),
0, 0, d_a, d_c); 0, 0, d_a, d_c);
@ -180,27 +143,21 @@ void HIPStream<T>::copy()
check_error(); check_error();
} }
template <size_t elements_per_lane, size_t chunks_per_block, typename T> template <size_t elements_per_lane, typename T>
__launch_bounds__(TBSIZE) __launch_bounds__(TBSIZE)
__global__ __global__
void mul_kernel(T * __restrict b, const T * __restrict c) void mul_kernel(T * __restrict b, const T * __restrict c)
{ {
const T scalar = startScalar; const T scalar = startScalar;
const size_t dx = (blockDim.x * gridDim.x) * elements_per_lane;
const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane; const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane;
for (size_t i = 0; i != chunks_per_block; ++i) for (size_t j = 0; j < elements_per_lane; ++j)
{ b[gidx + j] = scalar * c[gidx + j];
for (size_t j = 0; j != elements_per_lane; ++j)
{
store(scalar * load(c[gidx + i * dx + j]), b[gidx + i * dx + j]);
}
}
} }
template <class T> template <class T>
void HIPStream<T>::mul() void HIPStream<T>::mul()
{ {
hipLaunchKernelGGL(HIP_KERNEL_NAME(mul_kernel<elements_per_lane, chunks_per_block, T>), hipLaunchKernelGGL(HIP_KERNEL_NAME(mul_kernel<elements_per_lane, T>),
dim3(block_count), dim3(block_count),
dim3(TBSIZE), dim3(TBSIZE),
0, 0, d_b, d_c); 0, 0, d_b, d_c);
@ -209,26 +166,20 @@ void HIPStream<T>::mul()
check_error(); check_error();
} }
template <size_t elements_per_lane, size_t chunks_per_block, typename T> template <size_t elements_per_lane, typename T>
__launch_bounds__(TBSIZE) __launch_bounds__(TBSIZE)
__global__ __global__
void add_kernel(const T * __restrict a, const T * __restrict b, T * __restrict c) void add_kernel(const T * __restrict a, const T * __restrict b, T * __restrict c)
{ {
const size_t dx = (blockDim.x * gridDim.x) * elements_per_lane;
const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane; const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane;
for (size_t i = 0; i != chunks_per_block; ++i) for (size_t j = 0; j < elements_per_lane; ++j)
{ c[gidx + j] = a[gidx + j] + b[gidx + j];
for (size_t j = 0; j != elements_per_lane; ++j)
{
store(load(a[gidx + i * dx + j]) + load(b[gidx + i * dx + j]), c[gidx + i * dx + j]);
}
}
} }
template <class T> template <class T>
void HIPStream<T>::add() void HIPStream<T>::add()
{ {
hipLaunchKernelGGL(HIP_KERNEL_NAME(add_kernel<elements_per_lane, chunks_per_block, T>), hipLaunchKernelGGL(HIP_KERNEL_NAME(add_kernel<elements_per_lane, T>),
dim3(block_count), dim3(block_count),
dim3(TBSIZE), dim3(TBSIZE),
0, 0, d_a, d_b, d_c); 0, 0, d_a, d_b, d_c);
@ -237,27 +188,21 @@ void HIPStream<T>::add()
check_error(); check_error();
} }
template <size_t elements_per_lane, size_t chunks_per_block, typename T> template <size_t elements_per_lane, typename T>
__launch_bounds__(TBSIZE) __launch_bounds__(TBSIZE)
__global__ __global__
void triad_kernel(T * __restrict a, const T * __restrict b, const T * __restrict c) void triad_kernel(T * __restrict a, const T * __restrict b, const T * __restrict c)
{ {
const T scalar = startScalar; const T scalar = startScalar;
const size_t dx = (blockDim.x * gridDim.x) * elements_per_lane;
const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane; const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane;
for (size_t i = 0; i != chunks_per_block; ++i) for (size_t j = 0; j < elements_per_lane; ++j)
{ a[gidx + j] = b[gidx + j] + scalar * c[gidx + j];
for (size_t j = 0; j != elements_per_lane; ++j)
{
store(load(b[gidx + i * dx + j]) + scalar * load(c[gidx + i * dx + j]), a[gidx + i * dx + j]);
}
}
} }
template <class T> template <class T>
void HIPStream<T>::triad() void HIPStream<T>::triad()
{ {
hipLaunchKernelGGL(HIP_KERNEL_NAME(triad_kernel<elements_per_lane, chunks_per_block, T>), hipLaunchKernelGGL(HIP_KERNEL_NAME(triad_kernel<elements_per_lane, T>),
dim3(block_count), dim3(block_count),
dim3(TBSIZE), dim3(TBSIZE),
0, 0, d_a, d_b, d_c); 0, 0, d_a, d_b, d_c);
@ -266,91 +211,63 @@ void HIPStream<T>::triad()
check_error(); check_error();
} }
template <typename T> template <size_t elements_per_lane, typename T>
__global__ void nstream_kernel(T * a, const T * b, const T * c) __launch_bounds__(TBSIZE)
__global__ void nstream_kernel(T * __restrict a, const T * __restrict b, const T * __restrict c)
{ {
const T scalar = startScalar; const T scalar = startScalar;
const int i = hipBlockDim_x * hipBlockIdx_x + hipThreadIdx_x; const size_t gidx = (threadIdx.x + blockIdx.x * blockDim.x) * elements_per_lane;
a[i] += b[i] + scalar * c[i]; for (size_t j = 0; j < elements_per_lane; ++j)
a[gidx + j] += b[gidx + j] + scalar * c[gidx + j];
} }
template <class T> template <class T>
void HIPStream<T>::nstream() void HIPStream<T>::nstream()
{ {
hipLaunchKernelGGL(HIP_KERNEL_NAME(nstream_kernel<T>), dim3(array_size/TBSIZE), dim3(TBSIZE), 0, 0, d_a, d_b, d_c); hipLaunchKernelGGL(HIP_KERNEL_NAME(nstream_kernel<elements_per_lane, T>),
dim3(block_count),
dim3(TBSIZE),
0, 0, d_a, d_b, d_c);
check_error(); check_error();
hipDeviceSynchronize(); hipDeviceSynchronize();
check_error(); check_error();
} }
template<unsigned int n = TBSIZE> template <size_t elements_per_lane, typename T>
struct Reducer
{
template<typename I>
__device__
static
void reduce(I it) noexcept
{
if (n == 1) return;
#if defined(__HIP_PLATFORM_NVCC__)
constexpr unsigned int warpSize = 32;
#endif
constexpr bool is_same_warp{n <= warpSize * 2};
if (static_cast<int>(threadIdx.x) < n/2)
{
it[threadIdx.x] += it[threadIdx.x + n/2];
}
is_same_warp ? __threadfence_block() : __syncthreads();
Reducer<n/2>::reduce(it);
}
};
template<>
struct Reducer<1u> {
template<typename I>
__device__
static
void reduce(I) noexcept
{}
};
template <size_t elements_per_lane, size_t chunks_per_block, typename T>
__launch_bounds__(TBSIZE) __launch_bounds__(TBSIZE)
__global__ __global__ void dot_kernel(const T * __restrict a, const T * __restrict b, T * __restrict sum, int array_size)
__global__ void dot_kernel(const T * __restrict a, const T * __restrict b, T * __restrict sum)
{ {
__shared__ T tb_sum[TBSIZE]; __shared__ T tb_sum[TBSIZE];
const size_t tidx = threadIdx.x;
const size_t dx = (blockDim.x * gridDim.x) * elements_per_lane;
const size_t gidx = (tidx + blockIdx.x * blockDim.x) * elements_per_lane;
T tmp{0}; const size_t local_i = threadIdx.x;
for (size_t i = 0; i != chunks_per_block; ++i) size_t i = blockDim.x * blockIdx.x + local_i;
tb_sum[local_i] = 0.0;
for (size_t j = 0; j < elements_per_lane && i < array_size; ++j, i += blockDim.x*gridDim.x)
tb_sum[local_i] += a[i] * b[i];
for (size_t offset = blockDim.x / 2; offset > 0; offset /= 2)
{ {
for (size_t j = 0; j != elements_per_lane; ++j) __syncthreads();
if (local_i < offset)
{ {
tmp += load(a[gidx + i * dx + j]) * load(b[gidx + i * dx + j]); tb_sum[local_i] += tb_sum[local_i+offset];
} }
} }
tb_sum[tidx] = tmp;
__syncthreads();
Reducer<>::reduce(tb_sum); if (local_i == 0)
if (tidx) return; sum[blockIdx.x] = tb_sum[local_i];
store(tb_sum[0], sum[blockIdx.x]);
} }
template <class T> template <class T>
T HIPStream<T>::dot() T HIPStream<T>::dot()
{ {
hipLaunchKernelGGL(HIP_KERNEL_NAME(dot_kernel<elements_per_lane, chunks_per_block, T>), hipLaunchKernelGGL(HIP_KERNEL_NAME(dot_kernel<elements_per_lane, T>),
dim3(block_count), dim3(block_count),
dim3(TBSIZE), dim3(TBSIZE),
0, 0, d_a, d_b, d_sum); 0, 0, d_a, d_b, sums, array_size);
check_error(); check_error();
hipDeviceSynchronize();
hipMemcpy(sums, d_sum, block_count*sizeof(T), hipMemcpyDeviceToHost);
check_error(); check_error();
T sum = 0.0; T sum = 0.0;

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@ -22,16 +22,10 @@ class HIPStream : public Stream<T>
#ifndef DWORDS_PER_LANE #ifndef DWORDS_PER_LANE
#define DWORDS_PER_LANE 1 #define DWORDS_PER_LANE 1
#endif #endif
#ifndef CHUNKS_PER_BLOCK
#define CHUNKS_PER_BLOCK 8
#endif
#else #else
#ifndef DWORDS_PER_LANE #ifndef DWORDS_PER_LANE
#define DWORDS_PER_LANE 4 #define DWORDS_PER_LANE 4
#endif #endif
#ifndef CHUNKS_PER_BLOCK
#define CHUNKS_PER_BLOCK 1
#endif
#endif #endif
// Make sure that either: // Make sure that either:
// DWORDS_PER_LANE is less than sizeof(T), in which case we default to 1 element // DWORDS_PER_LANE is less than sizeof(T), in which case we default to 1 element
@ -41,7 +35,6 @@ class HIPStream : public Stream<T>
(DWORDS_PER_LANE * sizeof(unsigned int) % sizeof(T) == 0), (DWORDS_PER_LANE * sizeof(unsigned int) % sizeof(T) == 0),
"DWORDS_PER_LANE not divisible by sizeof(element_type)"); "DWORDS_PER_LANE not divisible by sizeof(element_type)");
static constexpr unsigned int chunks_per_block{CHUNKS_PER_BLOCK};
static constexpr unsigned int dwords_per_lane{DWORDS_PER_LANE}; static constexpr unsigned int dwords_per_lane{DWORDS_PER_LANE};
// Take into account the datatype size // Take into account the datatype size
// That is, if we specify 4 DWORDS_PER_LANE, this is 2 FP64 elements // That is, if we specify 4 DWORDS_PER_LANE, this is 2 FP64 elements

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@ -2,19 +2,9 @@
register_flag_required(CMAKE_CXX_COMPILER register_flag_required(CMAKE_CXX_COMPILER
"Absolute path to the AMD HIP C++ compiler") "Absolute path to the AMD HIP C++ compiler")
register_flag_optional(USE_NONTEMPORAL_MEM register_flag_optional(DWORDS_PER_LANE "Flag indicating the number of dwords to process per wavefront lane." 4)
"Flag indicating to use non-temporal memory accesses to bypass cache."
"OFF")
# TODO: Better flag descriptions
register_flag_optional(DWORDS_PER_LANE "Flag indicating the number of double data types per wavefront lane." 4)
register_flag_optional(CHUNKS_PER_BLOCK "Flag indicating the chunks per block." 1)
macro(setup) macro(setup)
# Ensure we set the proper preprocessor directives # Ensure we set the proper preprocessor directives
if (USE_NONTEMPORAL_MEM)
add_definitions(-DNONTEMPORAL)
endif ()
register_definitions(DWORDS_PER_LANE=${DWORDS_PER_LANE}) register_definitions(DWORDS_PER_LANE=${DWORDS_PER_LANE})
register_definitions(CHUNKS_PER_BLOCK=${CHUNKS_PER_BLOCK})
endmacro() endmacro()