internal/ceres/thread_token_provider.cc

// Ceres Solver - A fast non-linear least squares minimizer
// Copyright 2023 Google Inc. All rights reserved.
// http://ceres-solver.org/
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// Author: yp@photonscore.de (Yury Prokazov)

#include "ceres/thread_token_provider.h"

#include "absl/log/check.h"

namespace ceres::internal {

ThreadTokenProvider::ThreadTokenProvider(int num_threads) {
  for (int i = 0; i < num_threads; i++) {
    pool_.Push(i);
  }
}

int ThreadTokenProvider::Acquire() {
  int thread_id;
  CHECK(pool_.Wait(&thread_id));
  return thread_id;
}

void ThreadTokenProvider::Release(int thread_id) { pool_.Push(thread_id); }

}  // namespace ceres::internal