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authorGravatar Xiaoqiang Zheng <zhengxq@google.com>2016-05-07 22:22:44 -0800
committerGravatar TensorFlower Gardener <gardener@tensorflow.org>2016-05-09 09:21:14 -0700
commit6ff265ebae14586db5db623b7502ddbdbc8bbd12 (patch)
treed4df06ea887dfb603b22c9df1147b41b38994b54 /tensorflow/stream_executor
parenta846576a67da4bdd0b610a17b5c8d0d92e41f094 (diff)
Adding autotune to the Cudnn conv algorithm selection.
For now, use TF_CUDNN_USE_AUTOTUNE=1 to enable this feature. Once it is mature enough, it will be turned on by default. Support for the backward steps will be added later. Change: 121769364
Diffstat (limited to 'tensorflow/stream_executor')
-rw-r--r--tensorflow/stream_executor/cuda/cuda_dnn.cc169
-rw-r--r--tensorflow/stream_executor/cuda/cuda_dnn.h7
-rw-r--r--tensorflow/stream_executor/cuda/cuda_driver.cc10
-rw-r--r--tensorflow/stream_executor/dnn.cc5
-rw-r--r--tensorflow/stream_executor/dnn.h38
-rw-r--r--tensorflow/stream_executor/stream.cc36
-rw-r--r--tensorflow/stream_executor/stream.h12
-rw-r--r--tensorflow/stream_executor/stream_executor_pimpl.cc9
-rw-r--r--tensorflow/stream_executor/stream_executor_pimpl.h3
9 files changed, 248 insertions, 41 deletions
diff --git a/tensorflow/stream_executor/cuda/cuda_dnn.cc b/tensorflow/stream_executor/cuda/cuda_dnn.cc
index fbaa42effb..f35c59a82a 100644
--- a/tensorflow/stream_executor/cuda/cuda_dnn.cc
+++ b/tensorflow/stream_executor/cuda/cuda_dnn.cc
@@ -17,6 +17,7 @@ limitations under the License.
#include <dlfcn.h>
#include <functional>
+#include <memory>
#include "tensorflow/stream_executor/cuda/cuda_activation.h"
#include "tensorflow/stream_executor/cuda/cuda_diagnostics.h"
@@ -24,6 +25,7 @@ limitations under the License.
#include "tensorflow/stream_executor/cuda/cuda_gpu_executor.h"
#include "tensorflow/stream_executor/cuda/cuda_platform_id.h"
#include "tensorflow/stream_executor/cuda/cuda_stream.h"
+#include "tensorflow/stream_executor/cuda/cuda_timer.h"
#include "tensorflow/stream_executor/dnn.h"
#include "tensorflow/stream_executor/dso_loader.h"
#include "tensorflow/stream_executor/lib/env.h"
@@ -36,7 +38,9 @@ limitations under the License.
#include "tensorflow/stream_executor/scratch_allocator.h"
#include "tensorflow/stream_executor/stream.h"
#include "tensorflow/stream_executor/stream_executor_pimpl.h"
+// clang-format off
#include "third_party/gpus/cuda/include/cudnn.h"
+// clang-format on
namespace {
@@ -255,6 +259,22 @@ cudnnHandle_t ToHandle(void* opaque_handle) {
return static_cast<cudnnHandle_t>(opaque_handle);
}
+cudnnConvolutionFwdAlgo_t ToConvForwardAlgo(dnn::AlgorithmType algorithm) {
+ cudnnConvolutionFwdAlgo_t algo = cudnnConvolutionFwdAlgo_t(algorithm);
+ switch (algo) {
+ case CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_GEMM:
+ case CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM:
+ case CUDNN_CONVOLUTION_FWD_ALGO_GEMM:
+ case CUDNN_CONVOLUTION_FWD_ALGO_DIRECT:
+ case CUDNN_CONVOLUTION_FWD_ALGO_FFT:
+ case CUDNN_CONVOLUTION_FWD_ALGO_FFT_TILING:
+ return algo;
+ default:
+ LOG(FATAL) << "Unsupported Cudnn convolution forward algorithm: "
+ << algorithm;
+ }
+}
+
} // namespace
CudnnSupport::CudnnSupport(CUDAExecutor* parent)
@@ -647,7 +667,8 @@ bool CudnnSupport::DoConvolve(
const DeviceMemory<float>& filter_data,
const ConvolutionDescriptor& convolution_descriptor,
const BatchDescriptor& output_descriptor, DeviceMemory<float>* output_data,
- ScratchAllocator* scratch_allocator) {
+ ScratchAllocator* scratch_allocator, dnn::AlgorithmType algorithm,
+ dnn::ProfileResult* output_profile_result) {
ScopedTensorDescriptor input_nd{parent_, batch_descriptor, CUDNN_DATA_FLOAT};
ScopedTensorDescriptor output_nd{parent_, output_descriptor,
CUDNN_DATA_FLOAT};
@@ -667,52 +688,101 @@ bool CudnnSupport::DoConvolve(
// Beta is the scaling factor for output.
float beta = 0.0;
- auto get_algorithm = [&](bool specify_limit)
- SHARED_LOCKS_REQUIRED(dnn_handle_mutex_) {
- cudnnConvolutionFwdPreference_t preference =
- specify_limit ? CUDNN_CONVOLUTION_FWD_SPECIFY_WORKSPACE_LIMIT
- : CUDNN_CONVOLUTION_FWD_NO_WORKSPACE;
-
- auto memory_limit_bytes =
- scratch_allocator == nullptr
- ? 0
- : scratch_allocator->GetMemoryLimitInBytes(stream);
- if (memory_limit_bytes < 0) {
- memory_limit_bytes = 0;
- }
+ const bool is_profiling = output_profile_result != nullptr;
+ cudnnConvolutionFwdAlgo_t algo;
+ DeviceMemory<uint8> scratch;
- cudnnConvolutionFwdAlgo_t algo;
- status = dynload::cudnnGetConvolutionForwardAlgorithm(
- parent_, ToHandle(dnn_handle_), input_nd.handle(), filter.handle(),
- conv.handle(), output_nd.handle(),
- /*preference=*/preference,
- /*memoryLimitInBytes=*/memory_limit_bytes, /*algo=*/&algo);
- CHECK_EQ(status, CUDNN_STATUS_SUCCESS) << "Unable to find a suitable "
- "algorithm for doing forward "
- "convolution";
- return algo;
- };
+ if (algorithm == dnn::kDefaultAlgorithm) {
+ // With the default algorithm, use Cudnn's heuristics.
+ auto get_algorithm = [&](bool specify_limit)
+ SHARED_LOCKS_REQUIRED(dnn_handle_mutex_) {
+ cudnnConvolutionFwdPreference_t preference =
+ specify_limit ? CUDNN_CONVOLUTION_FWD_SPECIFY_WORKSPACE_LIMIT
+ : CUDNN_CONVOLUTION_FWD_NO_WORKSPACE;
+
+ auto memory_limit_bytes =
+ scratch_allocator == nullptr
+ ? 0
+ : scratch_allocator->GetMemoryLimitInBytes(stream);
+ if (memory_limit_bytes < 0) {
+ memory_limit_bytes = 0;
+ }
+
+ cudnnConvolutionFwdAlgo_t algo_to_use;
+ status = dynload::cudnnGetConvolutionForwardAlgorithm(
+ parent_, ToHandle(dnn_handle_), input_nd.handle(),
+ filter.handle(), conv.handle(), output_nd.handle(),
+ /*preference=*/preference,
+ /*memoryLimitInBytes=*/memory_limit_bytes,
+ /*algo=*/&algo_to_use);
+ CHECK_EQ(status, CUDNN_STATUS_SUCCESS)
+ << "Unable to find a suitable "
+ "algorithm for doing forward "
+ "convolution";
+ return algo_to_use;
+ };
+
+ algo = get_algorithm(/*specify_limit=*/scratch_allocator != nullptr);
+
+ if (scratch_allocator != nullptr) {
+ size_t size_in_bytes;
+ status = dynload::cudnnGetConvolutionForwardWorkspaceSize(
+ parent_, ToHandle(dnn_handle_), /*srcDesc=*/input_nd.handle(),
+ /*filterDesc=*/filter.handle(), /*convDesc=*/conv.handle(),
+ /*destDesc=*/output_nd.handle(), /*algo=*/algo,
+ /*sizeInBytes=*/&size_in_bytes);
+ if (status == CUDNN_STATUS_SUCCESS && size_in_bytes != 0) {
+ scratch = scratch_allocator->AllocateBytes(stream, size_in_bytes)
+ .ValueOrDie();
+ }
+ }
- auto algo = get_algorithm(/*specify_limit=*/scratch_allocator != nullptr);
+ // If we didn't allocate any scratch space (perhaps because of failed
+ // allocation), we force a switch back to the "no workspace" algorithm.
+ if (scratch == nullptr) {
+ algo = get_algorithm(/*specify_limit=*/false);
+ }
+ } else {
+ // An algorithm has been specified.
+ algo = ToConvForwardAlgo(algorithm);
- DeviceMemory<uint8> scratch;
- if (scratch_allocator != nullptr) {
size_t size_in_bytes;
status = dynload::cudnnGetConvolutionForwardWorkspaceSize(
parent_, ToHandle(dnn_handle_), /*srcDesc=*/input_nd.handle(),
/*filterDesc=*/filter.handle(), /*convDesc=*/conv.handle(),
/*destDesc=*/output_nd.handle(), /*algo=*/algo,
/*sizeInBytes=*/&size_in_bytes);
- if (status == CUDNN_STATUS_SUCCESS && size_in_bytes != 0) {
- scratch =
- scratch_allocator->AllocateBytes(stream, size_in_bytes).ValueOrDie();
+ if (status != CUDNN_STATUS_SUCCESS) {
+ if (is_profiling) {
+ // Silently return when we are profiling.
+ return false;
+ }
+ LOG(FATAL) << "Cannot query the size of workspace needed for the given "
+ "algorithm: "
+ << algorithm;
+ }
+ if (size_in_bytes != 0) {
+ if (scratch_allocator == nullptr) {
+ LOG(FATAL) << "An allocator must be specified when scratch memory is "
+ "needed";
+ }
+ auto allocated = scratch_allocator->AllocateBytes(stream, size_in_bytes);
+ if (is_profiling && !allocated.ok()) {
+ // Silently return when we are profiling.
+ return false;
+ }
+ scratch = allocated.ValueOrDie();
}
}
- // If we didn't allocate any scratch space (perhaps because of failed
- // allocation), we force a switch back to the "no workspace" algorithm.
- if (scratch == nullptr) {
- algo = get_algorithm(/*specify_limit=*/false);
+ std::unique_ptr<CUDATimer> timer;
+ if (is_profiling) {
+ timer.reset(new CUDATimer(parent_));
+ timer->Init();
+ // The start and stop of the timer should be as close to the Cudnn call as
+ // possible. It is still possible for other threads to issue workload on
+ // to this stream. So it could take multiple profiling measurements.
+ timer->Start(AsCUDAStream(stream));
}
status = dynload::cudnnConvolutionForward(
@@ -725,11 +795,38 @@ bool CudnnSupport::DoConvolve(
/*destDesc=*/output_nd.handle(), /*destData=*/output_data->opaque());
if (status != CUDNN_STATUS_SUCCESS) {
+ if (is_profiling) {
+ // Silently return when we are profiling.
+ return false;
+ }
LOG(FATAL) << "failed to enqueue convolution on stream: "
<< ToString(status);
- return false;
}
+ if (is_profiling) {
+ timer->Stop(AsCUDAStream(stream));
+ output_profile_result->set_is_valid(true);
+ output_profile_result->set_algorithm(algo);
+ output_profile_result->set_elapsed_time_in_ms(
+ timer->GetElapsedMilliseconds());
+ timer->Destroy();
+ }
+
+ return true;
+}
+
+bool CudnnSupport::GetConvolveAlgorithms(
+ std::vector<dnn::AlgorithmType>* out_algorithms) {
+ out_algorithms->assign({
+ // clang-format off
+ CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_GEMM,
+ CUDNN_CONVOLUTION_FWD_ALGO_IMPLICIT_PRECOMP_GEMM,
+ CUDNN_CONVOLUTION_FWD_ALGO_GEMM,
+ CUDNN_CONVOLUTION_FWD_ALGO_DIRECT,
+ CUDNN_CONVOLUTION_FWD_ALGO_FFT,
+ CUDNN_CONVOLUTION_FWD_ALGO_FFT_TILING,
+ // clang-format on
+ });
return true;
}
diff --git a/tensorflow/stream_executor/cuda/cuda_dnn.h b/tensorflow/stream_executor/cuda/cuda_dnn.h
index 37be60ec63..76af118962 100644
--- a/tensorflow/stream_executor/cuda/cuda_dnn.h
+++ b/tensorflow/stream_executor/cuda/cuda_dnn.h
@@ -44,6 +44,9 @@ class CudnnSupport : public dnn::DnnSupport {
port::Status Init() override;
+ bool GetConvolveAlgorithms(
+ std::vector<dnn::AlgorithmType>* out_algorithms) override;
+
bool DoConvolve(Stream* stream, const dnn::BatchDescriptor& input_descriptor,
const DeviceMemory<float>& input_data,
const dnn::FilterDescriptor& filter_descriptor,
@@ -51,7 +54,9 @@ class CudnnSupport : public dnn::DnnSupport {
const dnn::ConvolutionDescriptor& convolution_descriptor,
const dnn::BatchDescriptor& output_descriptor,
DeviceMemory<float>* output_data,
- ScratchAllocator* scratch_allocator) override;
+ ScratchAllocator* scratch_allocator,
+ dnn::AlgorithmType algorithm,
+ dnn::ProfileResult* output_profile_result) override;
bool DoConvolve(Stream* stream, const dnn::BatchDescriptor& batch_descriptor,
const DeviceMemory<double>& input_data,
diff --git a/tensorflow/stream_executor/cuda/cuda_driver.cc b/tensorflow/stream_executor/cuda/cuda_driver.cc
index c88dc88d29..66cfccdd90 100644
--- a/tensorflow/stream_executor/cuda/cuda_driver.cc
+++ b/tensorflow/stream_executor/cuda/cuda_driver.cc
@@ -94,6 +94,7 @@ PERFTOOLS_GPUTOOLS_LIBCUDA_WRAP(cuEventDestroy_v2);
PERFTOOLS_GPUTOOLS_LIBCUDA_WRAP(cuEventElapsedTime);
PERFTOOLS_GPUTOOLS_LIBCUDA_WRAP(cuEventQuery);
PERFTOOLS_GPUTOOLS_LIBCUDA_WRAP(cuEventRecord);
+PERFTOOLS_GPUTOOLS_LIBCUDA_WRAP(cuEventSynchronize);
PERFTOOLS_GPUTOOLS_LIBCUDA_WRAP(cuFuncGetAttribute);
PERFTOOLS_GPUTOOLS_LIBCUDA_WRAP(cuFuncSetCacheConfig);
PERFTOOLS_GPUTOOLS_LIBCUDA_WRAP(cuGetErrorName);
@@ -1069,7 +1070,14 @@ CUDADriver::ContextGetSharedMemConfig(CUcontext context) {
float *elapsed_milliseconds,
CUevent start, CUevent stop) {
ScopedActivateContext activated{context};
- CUresult res = dynload::cuEventElapsedTime(elapsed_milliseconds, start, stop);
+ // The stop event must have completed in order for cuEventElapsedTime to
+ // work.
+ CUresult res = dynload::cuEventSynchronize(stop);
+ if (res != CUDA_SUCCESS) {
+ LOG(ERROR) << "failed to synchronize the stop event: " << ToString(res);
+ return false;
+ }
+ res = dynload::cuEventElapsedTime(elapsed_milliseconds, start, stop);
if (res != CUDA_SUCCESS) {
LOG(ERROR) << "failed to get elapsed time between events: "
<< ToString(res);
diff --git a/tensorflow/stream_executor/dnn.cc b/tensorflow/stream_executor/dnn.cc
index 41f3bf83d3..7e98db723f 100644
--- a/tensorflow/stream_executor/dnn.cc
+++ b/tensorflow/stream_executor/dnn.cc
@@ -22,6 +22,11 @@ namespace perftools {
namespace gputools {
namespace dnn {
+bool DnnSupport::GetConvolveAlgorithms(
+ std::vector<AlgorithmType>* out_algorithms) {
+ return false;
+}
+
string QuantizedActivationModeString(QuantizedActivationMode mode) {
switch (mode) {
case dnn::QuantizedActivationMode::k8Bit:
diff --git a/tensorflow/stream_executor/dnn.h b/tensorflow/stream_executor/dnn.h
index 3d19f481c9..8cba8295db 100644
--- a/tensorflow/stream_executor/dnn.h
+++ b/tensorflow/stream_executor/dnn.h
@@ -527,6 +527,30 @@ class PoolingDescriptor {
std::vector<int64> strides_;
};
+typedef int64 AlgorithmType;
+constexpr AlgorithmType kDefaultAlgorithm = -1;
+
+// Describes the result from a perf experiment.
+//
+// Arguments:
+// is_valid: indicates whether a valid measurement was obtained.
+// algorithm: returns the exact algorithm that was used.
+// elapsed_time_in_ms: returns the measured elapsed time in milliseconds.
+class ProfileResult {
+ public:
+ bool is_valid() const { return is_valid_; }
+ void set_is_valid(bool val) { is_valid_ = val; }
+ AlgorithmType algorithm() const { return algorithm_; }
+ void set_algorithm(AlgorithmType val) { algorithm_ = val; }
+ float elapsed_time_in_ms() const { return elapsed_time_in_ms_; }
+ void set_elapsed_time_in_ms(float val) { elapsed_time_in_ms_ = val; }
+
+ private:
+ bool is_valid_ = false;
+ AlgorithmType algorithm_ = kDefaultAlgorithm;
+ float elapsed_time_in_ms_ = -1.0f;
+};
+
// Describes a local response normalization (LRN). LRN is used e.g. in
// dist_belief.
//
@@ -655,6 +679,12 @@ class DnnSupport {
// convolution result.
// scratch_allocator: un-owned, may-be-null object that may allocate scratch
// space in order to speed up the convolution operation.
+ // algorithm: an integer to specify which algorithm should be used for the
+ // operation. kDefaultAlgorithm means the system will pick an algorithm
+ // by default. The coding of the algorithm is be interpretted by the
+ // underlying implementation.
+ // output_profile_result: the output profile result for this call. The
+ // profiling is only enabled when this is not nullptr.
//
// input_descriptor, filter_descriptor, convolution_descriptor and
// output_descriptor together specify exactly how the convolution is aligned
@@ -677,8 +707,12 @@ class DnnSupport {
const DeviceMemory<float>& filter_data,
const dnn::ConvolutionDescriptor& convolution_descriptor,
const dnn::BatchDescriptor& output_descriptor,
- DeviceMemory<float>* output_data,
- ScratchAllocator* scratch_allocator) = 0;
+ DeviceMemory<float>* output_data, ScratchAllocator* scratch_allocator,
+ AlgorithmType algorithm, ProfileResult* output_profile_result) = 0;
+
+ // Return a list of algorithms supported by the forward convolution pass.
+ virtual bool GetConvolveAlgorithms(
+ std::vector<AlgorithmType>* out_algorithms);
// Enqueues a double-precision convolution operation onto the stream.
// See DoConvolve above for argument details.
diff --git a/tensorflow/stream_executor/stream.cc b/tensorflow/stream_executor/stream.cc
index cee781f77b..b02df02c90 100644
--- a/tensorflow/stream_executor/stream.cc
+++ b/tensorflow/stream_executor/stream.cc
@@ -295,7 +295,41 @@ Stream &Stream::ThenConvolveWithScratch(
CheckError(dnn->DoConvolve(
this, input_descriptor, input_data, filter_descriptor, filter_data,
convolution_descriptor, output_descriptor, output,
- /*scratch_allocator=*/scratch_allocator));
+ /*scratch_allocator=*/scratch_allocator, dnn::kDefaultAlgorithm,
+ nullptr));
+ } else {
+ SetError();
+ LOG(WARNING)
+ << "attempting to perform DNN operation using StreamExecutor "
+ "without DNN support";
+ }
+ }
+ return *this;
+}
+
+Stream &Stream::ThenConvolveWithAlgorithm(
+ const dnn::BatchDescriptor &input_descriptor,
+ const DeviceMemory<float> &input_data,
+ const dnn::FilterDescriptor &filter_descriptor,
+ const DeviceMemory<float> &filter_data,
+ const dnn::ConvolutionDescriptor &convolution_descriptor,
+ const dnn::BatchDescriptor &output_descriptor, DeviceMemory<float> *output,
+ ScratchAllocator *scratch_allocator, dnn::AlgorithmType algorithm,
+ dnn::ProfileResult *output_profile_result) {
+ VLOG_CALL(PARAM(input_descriptor), PARAM(input_data),
+ PARAM(filter_descriptor), PARAM(filter_data),
+ PARAM(convolution_descriptor), PARAM(output_descriptor),
+ PARAM(output));
+
+ if (ok()) {
+ if (dnn::DnnSupport *dnn = parent_->AsDnn()) {
+ auto status = dnn->DoConvolve(
+ this, input_descriptor, input_data, filter_descriptor, filter_data,
+ convolution_descriptor, output_descriptor, output, scratch_allocator,
+ algorithm, output_profile_result);
+ if (!status && !output_profile_result) {
+ SetError();
+ }
} else {
SetError();
LOG(WARNING)
diff --git a/tensorflow/stream_executor/stream.h b/tensorflow/stream_executor/stream.h
index 599146f49b..ca52949657 100644
--- a/tensorflow/stream_executor/stream.h
+++ b/tensorflow/stream_executor/stream.h
@@ -66,6 +66,8 @@ namespace dnn {
struct BatchDescriptor;
struct FilterDescriptor;
struct ConvolutionDescriptor;
+struct ProfileResult;
+typedef int64 AlgorithmType;
} // namespace dnn
class StreamExecutor;
@@ -228,6 +230,16 @@ class Stream {
const dnn::BatchDescriptor &output_descriptor,
DeviceMemory<float> *output, ScratchAllocator *scratch_allocator);
+ Stream &ThenConvolveWithAlgorithm(
+ const dnn::BatchDescriptor &input_descriptor,
+ const DeviceMemory<float> &input_data,
+ const dnn::FilterDescriptor &filter_descriptor,
+ const DeviceMemory<float> &filter_data,
+ const dnn::ConvolutionDescriptor &convolution_descriptor,
+ const dnn::BatchDescriptor &output_descriptor,
+ DeviceMemory<float> *output, ScratchAllocator *scratch_allocator,
+ dnn::AlgorithmType algorithm, dnn::ProfileResult *output_profile_result);
+
Stream &ThenSeparableConvolve(
const dnn::BatchDescriptor &input_descriptor,
const DeviceMemory<float> &input_data,
diff --git a/tensorflow/stream_executor/stream_executor_pimpl.cc b/tensorflow/stream_executor/stream_executor_pimpl.cc
index acaa0efcb2..fe32039d71 100644
--- a/tensorflow/stream_executor/stream_executor_pimpl.cc
+++ b/tensorflow/stream_executor/stream_executor_pimpl.cc
@@ -286,6 +286,15 @@ bool StreamExecutor::SupportsDnn() const {
return implementation_->SupportsDnn();
}
+bool StreamExecutor::GetConvolveAlgorithms(
+ std::vector<dnn::AlgorithmType> *out_algorithms) {
+ dnn::DnnSupport *dnn_support = AsDnn();
+ if (!dnn_support) {
+ return false;
+ }
+ return dnn_support->GetConvolveAlgorithms(out_algorithms);
+}
+
dnn::DnnSupport *StreamExecutor::AsDnn() {
mutex_lock lock{mu_};
if (dnn_ != nullptr) {
diff --git a/tensorflow/stream_executor/stream_executor_pimpl.h b/tensorflow/stream_executor/stream_executor_pimpl.h
index f624e0fcdb..31b110a8e0 100644
--- a/tensorflow/stream_executor/stream_executor_pimpl.h
+++ b/tensorflow/stream_executor/stream_executor_pimpl.h
@@ -338,6 +338,9 @@ class StreamExecutor {
// platform that underlies this interface.
bool SupportsDnn() const;
+ // Get the list of supported algorithms for the forward convolution opeartion.
+ bool GetConvolveAlgorithms(std::vector<dnn::AlgorithmType> *out_algorithms);
+
// Returns the device ordinal that this StreamExecutor was initialized with.
// Meaningless before initialization.
int device_ordinal() const { return device_ordinal_; }