| // Ceres Solver - A fast non-linear least squares minimizer |
| // Copyright 2018 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) |
| |
| // This include must come before any #ifndef check on Ceres compile options. |
| // clang-format off |
| #include "ceres/internal/config.h" |
| // clang-format on |
| |
| #include "ceres/parallel_for.h" |
| |
| #include <cmath> |
| #include <condition_variable> |
| #include <mutex> |
| #include <thread> |
| #include <vector> |
| |
| #include "ceres/context_impl.h" |
| #include "glog/logging.h" |
| #include "gmock/gmock.h" |
| #include "gtest/gtest.h" |
| |
| namespace ceres::internal { |
| |
| using testing::ElementsAreArray; |
| using testing::UnorderedElementsAreArray; |
| |
| // Tests the parallel for loop computes the correct result for various number of |
| // threads. |
| TEST(ParallelFor, NumThreads) { |
| ContextImpl context; |
| context.EnsureMinimumThreads(/*num_threads=*/2); |
| |
| const int size = 16; |
| std::vector<int> expected_results(size, 0); |
| for (int i = 0; i < size; ++i) { |
| expected_results[i] = std::sqrt(i); |
| } |
| |
| for (int num_threads = 1; num_threads <= 8; ++num_threads) { |
| std::vector<int> values(size, 0); |
| ParallelFor(&context, 0, size, num_threads, [&values](int i) { |
| values[i] = std::sqrt(i); |
| }); |
| EXPECT_THAT(values, ElementsAreArray(expected_results)); |
| } |
| } |
| |
| // Tests the parallel for loop with the thread ID interface computes the correct |
| // result for various number of threads. |
| TEST(ParallelForWithThreadId, NumThreads) { |
| ContextImpl context; |
| context.EnsureMinimumThreads(/*num_threads=*/2); |
| |
| const int size = 16; |
| std::vector<int> expected_results(size, 0); |
| for (int i = 0; i < size; ++i) { |
| expected_results[i] = std::sqrt(i); |
| } |
| |
| for (int num_threads = 1; num_threads <= 8; ++num_threads) { |
| std::vector<int> values(size, 0); |
| ParallelFor( |
| &context, 0, size, num_threads, [&values](int thread_id, int i) { |
| values[i] = std::sqrt(i); |
| }); |
| EXPECT_THAT(values, ElementsAreArray(expected_results)); |
| } |
| } |
| |
| // Tests nested for loops do not result in a deadlock. |
| TEST(ParallelFor, NestedParallelForDeadlock) { |
| ContextImpl context; |
| context.EnsureMinimumThreads(/*num_threads=*/2); |
| |
| // Increment each element in the 2D matrix. |
| std::vector<std::vector<int>> x(3, {1, 2, 3}); |
| ParallelFor(&context, 0, 3, 2, [&x, &context](int i) { |
| std::vector<int>& y = x.at(i); |
| ParallelFor(&context, 0, 3, 2, [&y](int j) { ++y.at(j); }); |
| }); |
| |
| const std::vector<int> results = {2, 3, 4}; |
| for (const std::vector<int>& value : x) { |
| EXPECT_THAT(value, ElementsAreArray(results)); |
| } |
| } |
| |
| // Tests nested for loops do not result in a deadlock for the parallel for with |
| // thread ID interface. |
| TEST(ParallelForWithThreadId, NestedParallelForDeadlock) { |
| ContextImpl context; |
| context.EnsureMinimumThreads(/*num_threads=*/2); |
| |
| // Increment each element in the 2D matrix. |
| std::vector<std::vector<int>> x(3, {1, 2, 3}); |
| ParallelFor(&context, 0, 3, 2, [&x, &context](int thread_id, int i) { |
| std::vector<int>& y = x.at(i); |
| ParallelFor(&context, 0, 3, 2, [&y](int thread_id, int j) { ++y.at(j); }); |
| }); |
| |
| const std::vector<int> results = {2, 3, 4}; |
| for (const std::vector<int>& value : x) { |
| EXPECT_THAT(value, ElementsAreArray(results)); |
| } |
| } |
| |
| // This test is only valid when multithreading support is enabled. |
| #ifndef CERES_NO_THREADS |
| TEST(ParallelForWithThreadId, UniqueThreadIds) { |
| // Ensure the hardware supports more than 1 thread to ensure the test will |
| // pass. |
| const int num_hardware_threads = std::thread::hardware_concurrency(); |
| if (num_hardware_threads <= 1) { |
| LOG(ERROR) |
| << "Test not supported, the hardware does not support threading."; |
| return; |
| } |
| |
| ContextImpl context; |
| context.EnsureMinimumThreads(/*num_threads=*/2); |
| // Increment each element in the 2D matrix. |
| std::vector<int> x(2, -1); |
| std::mutex mutex; |
| std::condition_variable condition; |
| int count = 0; |
| ParallelFor(&context, |
| 0, |
| 2, |
| 2, |
| [&x, &mutex, &condition, &count](int thread_id, int i) { |
| std::unique_lock<std::mutex> lock(mutex); |
| x[i] = thread_id; |
| ++count; |
| condition.notify_all(); |
| condition.wait(lock, [&]() { return count == 2; }); |
| }); |
| |
| EXPECT_THAT(x, UnorderedElementsAreArray({0, 1})); |
| } |
| #endif // CERES_NO_THREADS |
| |
| } // namespace ceres::internal |