EventCountTest.cpp File Reference

#include <folly/experimental/EventCount.h>
#include <algorithm>
#include <atomic>
#include <random>
#include <thread>
#include <vector>
#include <glog/logging.h>
#include <folly/Random.h>
#include <folly/portability/GTest.h>

Go to the source code of this file.

Functions
	TEST (EventCount, Simple)

Function Documentation

TEST	(	EventCount	,
		Simple
	)

Definition at line 82 of file EventCountTest.cpp.

References count, EXPECT_EQ, ops, folly::randomNumberSeed(), and threads.

                         {
  // We're basically testing for no deadlock.
  static const size_t count = 300000;

  enum class Op {
    UP,
    DOWN,
  };
  std::vector<std::pair<Op, int>> ops;
  std::mt19937 rnd(randomNumberSeed());
  randomPartition(rnd, Op::UP, count, ops);
  size_t uppers = ops.size();
  randomPartition(rnd, Op::DOWN, count, ops);
  size_t downers = ops.size() - uppers;
  VLOG(1) << "Using " << ops.size() << " threads: uppers=" << uppers
          << " downers=" << downers << " sem_count=" << count;

  std::shuffle(ops.begin(), ops.end(), std::mt19937(std::random_device()()));

  std::vector<std::thread> threads;
  threads.reserve(ops.size());

  Semaphore sem;
  for (auto& op : ops) {
    int n = op.second;
    if (op.first == Op::UP) {
      auto fn = [&sem, n]() mutable {
        while (n--) {
          sem.up();
        }
      };
      threads.push_back(std::thread(fn));
    } else {
      auto fn = [&sem, n]() mutable {
        while (n--) {
          sem.down();
        }
      };
      threads.push_back(std::thread(fn));
    }
  }

  for (auto& thread : threads) {
    thread.join();
  }

  EXPECT_EQ(0, sem.value());
}