Aaryaman Sagar 77273d4137 Fix TSAN failures in DistributedMutex tests (#5684)
Summary:
TSAN was not able to correctly instrument atomic bts and btr instructions, so
when TSAN is enabled implement those with std::atomic::fetch_or and
std::atomic::fetch_and. Also disable tests that fail on TSAN with false
negatives (we know these are false negatives because this other verifiably
correct program fails with the same TSAN error <link>)

```
make clean
TEST_TMPDIR=/dev/shm/rocksdb OPT=-g COMPILE_WITH_TSAN=1 make J=1 -j56 folly_synchronization_distributed_mutex_test
```

This is the code that fails with the same false-negative with TSAN
```
namespace {
class ExceptionWithConstructionTrack : public std::exception {
 public:
  explicit ExceptionWithConstructionTrack(int id)
      : id_{folly::to<std::string>(id)}, constructionTrack_{id} {}

  const char* what() const noexcept override {
    return id_.c_str();
  }

 private:
  std::string id_;
  TestConstruction constructionTrack_;
};

template <typename Storage, typename Atomic>
void transferCurrentException(Storage& storage, Atomic& produced) {
  assert(std::current_exception());
  new (&storage) std::exception_ptr(std::current_exception());
  produced->store(true, std::memory_order_release);
}

void concurrentExceptionPropagationStress(
    int numThreads,
    std::chrono::milliseconds milliseconds) {
  auto&& stop = std::atomic<bool>{false};
  auto&& exceptions = std::vector<std::aligned_storage<48, 8>::type>{};
  auto&& produced = std::vector<std::unique_ptr<std::atomic<bool>>>{};
  auto&& consumed = std::vector<std::unique_ptr<std::atomic<bool>>>{};
  auto&& consumers = std::vector<std::thread>{};
  for (auto i = 0; i < numThreads; ++i) {
    produced.emplace_back(new std::atomic<bool>{false});
    consumed.emplace_back(new std::atomic<bool>{false});
    exceptions.push_back({});
  }

  auto producer = std::thread{[&]() {
    auto counter = std::vector<int>(numThreads, 0);
    for (auto i = 0; true; i = ((i + 1) % numThreads)) {
      try {
        throw ExceptionWithConstructionTrack{counter.at(i)++};
      } catch (...) {
        transferCurrentException(exceptions.at(i), produced.at(i));
      }

      while (!consumed.at(i)->load(std::memory_order_acquire)) {
        if (stop.load(std::memory_order_acquire)) {
          return;
        }
      }

      consumed.at(i)->store(false, std::memory_order_release);
    }
  }};

  for (auto i = 0; i < numThreads; ++i) {
    consumers.emplace_back([&, i]() {
      auto counter = 0;
      while (true) {
        while (!produced.at(i)->load(std::memory_order_acquire)) {
          if (stop.load(std::memory_order_acquire)) {
            return;
          }
        }
        produced.at(i)->store(false, std::memory_order_release);

        try {
          auto storage = &exceptions.at(i);
          auto exc = folly::launder(
            reinterpret_cast<std::exception_ptr*>(storage));
          auto copy = std::move(*exc);
          exc->std::exception_ptr::~exception_ptr();
          std::rethrow_exception(std::move(copy));
        } catch (std::exception& exc) {
          auto value = std::stoi(exc.what());
          EXPECT_EQ(value, counter++);
        }

        consumed.at(i)->store(true, std::memory_order_release);
      }
    });
  }

  std::this_thread::sleep_for(milliseconds);
  stop.store(true);
  producer.join();
  for (auto& thread : consumers) {
    thread.join();
  }
}
} // namespace
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5684

Differential Revision: D16746077

Pulled By: miasantreble

fbshipit-source-id: 8af88dcf9161c05daec1a76290f577918638f79d
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RocksDB: A Persistent Key-Value Store for Flash and RAM Storage

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RocksDB is developed and maintained by Facebook Database Engineering Team. It is built on earlier work on LevelDB by Sanjay Ghemawat (sanjay@google.com) and Jeff Dean (jeff@google.com)

This code is a library that forms the core building block for a fast key value server, especially suited for storing data on flash drives. It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF) and Space-Amplification-Factor (SAF). It has multi-threaded compactions, making it specially suitable for storing multiple terabytes of data in a single database.

Start with example usage here: https://github.com/facebook/rocksdb/tree/master/examples

See the github wiki for more explanation.

The public interface is in include/. Callers should not include or rely on the details of any other header files in this package. Those internal APIs may be changed without warning.

Design discussions are conducted in https://www.facebook.com/groups/rocksdb.dev/

License

RocksDB is dual-licensed under both the GPLv2 (found in the COPYING file in the root directory) and Apache 2.0 License (found in the LICENSE.Apache file in the root directory). You may select, at your option, one of the above-listed licenses.

Description
A library that provides an embeddable, persistent key-value store for fast storage.
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