feat add marl for fiber

3party/marl/include/marl/mutex.h

@@ -0,0 +1,109 @@
+// Copyright 2020 The Marl Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Wrappers around std::mutex and std::unique_lock that provide clang's
+// Thread Safety Analysis annotations.
+// See: https://clang.llvm.org/docs/ThreadSafetyAnalysis.html
+
+#ifndef marl_mutex_h
+#define marl_mutex_h
+
+#include "export.h"
+#include "tsa.h"
+
+#include <condition_variable>
+#include <mutex>
+
+namespace marl {
+
+// mutex is a wrapper around std::mutex that offers Thread Safety Analysis
+// annotations.
+// mutex also holds methods for performing std::condition_variable::wait() calls
+// as these require a std::unique_lock<> which are unsupported by the TSA.
+class CAPABILITY("mutex") mutex {
+ public:
+  MARL_NO_EXPORT inline void lock() ACQUIRE() { _.lock(); }
+
+  MARL_NO_EXPORT inline void unlock() RELEASE() { _.unlock(); }
+
+  MARL_NO_EXPORT inline bool try_lock() TRY_ACQUIRE(true) {
+    return _.try_lock();
+  }
+
+  // wait_locked calls cv.wait() on this already locked mutex.
+  template <typename Predicate>
+  MARL_NO_EXPORT inline void wait_locked(std::condition_variable& cv,
+                                         Predicate&& p) REQUIRES(this) {
+    std::unique_lock<std::mutex> lock(_, std::adopt_lock);
+    cv.wait(lock, std::forward<Predicate>(p));
+    lock.release();  // Keep lock held.
+  }
+
+  // wait_until_locked calls cv.wait() on this already locked mutex.
+  template <typename Predicate, typename Time>
+  MARL_NO_EXPORT inline bool wait_until_locked(std::condition_variable& cv,
+                                               Time&& time,
+                                               Predicate&& p) REQUIRES(this) {
+    std::unique_lock<std::mutex> lock(_, std::adopt_lock);
+    auto res = cv.wait_until(lock, std::forward<Time>(time),
+                             std::forward<Predicate>(p));
+    lock.release();  // Keep lock held.
+    return res;
+  }
+
+ private:
+  friend class lock;
+  std::mutex _;
+};
+
+// lock is a RAII lock helper that offers Thread Safety Analysis annotations.
+// lock also holds methods for performing std::condition_variable::wait()
+// calls as these require a std::unique_lock<> which are unsupported by the TSA.
+class SCOPED_CAPABILITY lock {
+ public:
+  inline lock(mutex& m) ACQUIRE(m) : _(m._) {}
+  inline ~lock() RELEASE() = default;
+
+  // wait calls cv.wait() on this lock.
+  template <typename Predicate>
+  inline void wait(std::condition_variable& cv, Predicate&& p) {
+    cv.wait(_, std::forward<Predicate>(p));
+  }
+
+  // wait_until calls cv.wait() on this lock.
+  template <typename Predicate, typename Time>
+  inline bool wait_until(std::condition_variable& cv,
+                         Time&& time,
+                         Predicate&& p) {
+    return cv.wait_until(_, std::forward<Time>(time),
+                         std::forward<Predicate>(p));
+  }
+
+  inline bool owns_lock() const { return _.owns_lock(); }
+
+  // lock_no_tsa locks the mutex outside of the visiblity of the thread
+  // safety analysis. Use with caution.
+  inline void lock_no_tsa() { _.lock(); }
+
+  // unlock_no_tsa unlocks the mutex outside of the visiblity of the thread
+  // safety analysis. Use with caution.
+  inline void unlock_no_tsa() { _.unlock(); }
+
+ private:
+  std::unique_lock<std::mutex> _;
+};
+
+}  // namespace marl
+
+#endif  // marl_mutex_h