| // Ceres Solver - A fast non-linear least squares minimizer |
| // Copyright 2023 Google Inc. All rights reserved. |
| // http://ceres-solver.org/ |
| // |
| // 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 Google Inc. 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 OWNER 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. |
| // |
| // Author: vitus@google.com (Michael Vitus) |
| |
| #ifndef CERES_INTERNAL_CONTEXT_IMPL_H_ |
| #define CERES_INTERNAL_CONTEXT_IMPL_H_ |
| |
| // This include must come before any #ifndef check on Ceres compile options. |
| // clang-format off |
| #include "ceres/internal/config.h" |
| // clang-format on |
| |
| #include <string> |
| |
| #include "ceres/context.h" |
| #include "ceres/internal/disable_warnings.h" |
| #include "ceres/internal/export.h" |
| |
| #ifndef CERES_NO_CUDA |
| #include "cublas_v2.h" |
| #include "cuda_runtime.h" |
| #include "cusolverDn.h" |
| #include "cusparse.h" |
| #endif // CERES_NO_CUDA |
| |
| #include "ceres/thread_pool.h" |
| |
| namespace ceres::internal { |
| |
| class CERES_NO_EXPORT ContextImpl final : public Context { |
| public: |
| ContextImpl(); |
| ~ContextImpl() override; |
| ContextImpl(const ContextImpl&) = delete; |
| void operator=(const ContextImpl&) = delete; |
| |
| // When compiled with C++ threading support, resize the thread pool to have |
| // at min(num_thread, num_hardware_threads) where num_hardware_threads is |
| // defined by the hardware. Otherwise this call is a no-op. |
| void EnsureMinimumThreads(int num_threads); |
| |
| ThreadPool thread_pool; |
| |
| #ifndef CERES_NO_CUDA |
| // Note on Ceres' use of CUDA Devices on multi-GPU systems: |
| // 1. On a multi-GPU system, if nothing special is done, the "default" CUDA |
| // device will be used, which is device 0. |
| // 2. If the user masks out GPUs using the CUDA_VISIBLE_DEVICES environment |
| // variable, Ceres will still use device 0 visible to the program, but |
| // device 0 will be the first GPU indicated in the environment variable. |
| // 3. If the user explicitly selects a GPU in the host process before calling |
| // Ceres, Ceres will use that GPU. |
| |
| // Note on Ceres' use of CUDA Streams: |
| // Most of operations on the GPU are performed using a single stream. In |
| // those cases DefaultStream() should be used. This ensures that operations |
| // are stream-ordered, and might be concurrent with cpu processing with no |
| // additional efforts. |
| // |
| // a. Single-stream workloads |
| // - Only use default stream |
| // - Return control to the callee without synchronization whenever possible |
| // - Stream synchronization occurs only after GPU to CPU transfers, and is |
| // handled by CudaBuffer |
| // |
| // b. Multi-stream workloads |
| // Multi-stream workloads are more restricted in order to make it harder to |
| // get a race-condition. |
| // - Should always synchronize the default stream on entry |
| // - Should always synchronize all utilized streams on exit |
| // - Should not make any assumptions on one of streams_[] being default |
| // |
| // With those rules in place |
| // - All single-stream asynchronous workloads are serialized using default |
| // stream |
| // - Multiple-stream workloads always wait single-stream workloads to finish |
| // and leave no running computations on exit. |
| // This slightly penalizes multi-stream workloads, but makes it easier to |
| // avoid race conditions when multiple-stream workload depends on results of |
| // any preceeding gpu computations. |
| |
| // Initializes cuBLAS, cuSOLVER, and cuSPARSE contexts, creates an |
| // asynchronous CUDA stream, and associates the stream with the contexts. |
| // Returns true iff initialization was successful, else it returns false and a |
| // human-readable error message is returned. |
| bool InitCuda(std::string* message); |
| void TearDown(); |
| inline bool IsCudaInitialized() const { return is_cuda_initialized_; } |
| // Returns a human-readable string describing the capabilities of the current |
| // CUDA device. CudaConfigAsString can only be called after InitCuda has been |
| // called. |
| std::string CudaConfigAsString() const; |
| // Returns the number of bytes of available global memory on the current CUDA |
| // device. If it is called before InitCuda, it returns 0. |
| size_t GpuMemoryAvailable() const; |
| |
| cusolverDnHandle_t cusolver_handle_ = nullptr; |
| cublasHandle_t cublas_handle_ = nullptr; |
| |
| // Default stream. |
| // Kernel invocations and memory copies on this stream can be left without |
| // synchronization. |
| cudaStream_t DefaultStream() { return streams_[0]; } |
| static constexpr int kNumCudaStreams = 2; |
| cudaStream_t streams_[kNumCudaStreams] = {0}; |
| |
| cusparseHandle_t cusparse_handle_ = nullptr; |
| bool is_cuda_initialized_ = false; |
| int gpu_device_id_in_use_ = -1; |
| cudaDeviceProp gpu_device_properties_; |
| bool is_cuda_memory_pools_supported_ = false; |
| int cuda_version_major_ = 0; |
| int cuda_version_minor_ = 0; |
| #endif // CERES_NO_CUDA |
| }; |
| |
| } // namespace ceres::internal |
| |
| #include "ceres/internal/reenable_warnings.h" |
| |
| #endif // CERES_INTERNAL_CONTEXT_IMPL_H_ |