Switch away from using the legacy Synchronized macros

Summary: [Folly] Switch away from using the legacy `Synchronized` macros within Folly.

Reviewed By: simpkins

Differential Revision: D7118324

fbshipit-source-id: 328ecdd572d84bb99a28ddb8689bdc4ae08421a6

folly/experimental/exception_tracer/ExceptionCounterLib.cpp

@@ -119,7 +119,7 @@ void throwHandler(void*, std::type_info* exType, void (*)(void*)) noexcept {
   auto exceptionId =
       folly::hash::SpookyHashV2::Hash64(frames, (n + 1) * sizeof(frames[0]), 0);
 
-  SYNCHRONIZED(holder, gExceptionStats->statsHolder) {
+  gExceptionStats->statsHolder.withWLock([&](auto& holder) {
     auto it = holder.find(exceptionId);
     if (it != holder.end()) {
       ++it->second.count;
@@ -129,7 +129,7 @@ void throwHandler(void*, std::type_info* exType, void (*)(void*)) noexcept {
       info.frames.assign(frames + 1, frames + 1 + n);
       holder.emplace(exceptionId, ExceptionStats{1, std::move(info)});
     }
-  }
+  });
 }
 
 struct Initializer {

folly/experimental/exception_tracer/ExceptionTracerLib.cpp

@@ -47,20 +47,17 @@ template <typename Function>
 class CallbackHolder {
  public:
   void registerCallback(Function f) {
-    SYNCHRONIZED(callbacks_) {
-      callbacks_.push_back(std::move(f));
-    }
+    callbacks_.wlock()->push_back(std::move(f));
   }
 
   // always inline to enforce kInternalFramesNumber
   template <typename... Args>
   FOLLY_ALWAYS_INLINE void invoke(Args... args) {
-    SYNCHRONIZED_CONST(callbacks_) {
-      for (auto& cb : callbacks_) {
+    auto callbacksLock = callbacks_.rlock();
+    for (auto& cb : *callbacksLock) {
       cb(args...);
     }
   }
-  }
 
  private:
   folly::Synchronized<std::vector<Function>> callbacks_;

folly/fibers/FiberManagerMap.cpp

@@ -99,14 +99,14 @@ class ThreadLocalCache {
 
   static void erase(EventBaseT& evb) {
     for (auto& localInstance : instance().accessAllThreads()) {
-      SYNCHRONIZED(info, localInstance.eraseInfo_) {
+      localInstance.eraseInfo_.withWLock([&](auto& info) {
         if (info.eraseList.size() >= kEraseListMaxSize) {
           info.eraseAll = true;
         } else {
           info.eraseList.push_back(&evb);
         }
         localInstance.eraseRequested_ = true;
-      }
+      });
     }
   }
 
@@ -143,7 +143,7 @@ class ThreadLocalCache {
       return;
     }
 
-    SYNCHRONIZED(info, eraseInfo_) {
+    eraseInfo_.withWLock([&](auto& info) {
       if (info.eraseAll) {
         map_.clear();
       } else {
@@ -155,7 +155,7 @@ class ThreadLocalCache {
       info.eraseList.clear();
       info.eraseAll = false;
       eraseRequested_ = false;
-    }
+    });
   }
 
   std::unordered_map<EventBaseT*, FiberManager*> map_;

folly/fibers/GuardPageAllocator.cpp

@@ -90,9 +90,7 @@ class StackCache {
     auto p = freeList_.back().first;
     if (!freeList_.back().second) {
       PCHECK(0 == ::mprotect(p, pagesize(), PROT_NONE));
-      SYNCHRONIZED(pages, protectedPages()) {
-        pages.insert(reinterpret_cast<intptr_t>(p));
-      }
+      protectedPages().wlock()->insert(reinterpret_cast<intptr_t>(p));
     }
     freeList_.pop_back();
 
@@ -132,25 +130,25 @@ class StackCache {
 
   ~StackCache() {
     assert(storage_);
-    SYNCHRONIZED(pages, protectedPages()) {
+    protectedPages().withWLock([&](auto& pages) {
       for (const auto& item : freeList_) {
         pages.erase(reinterpret_cast<intptr_t>(item.first));
       }
-    }
+    });
     PCHECK(0 == ::munmap(storage_, allocSize_ * kNumGuarded));
   }
 
   static bool isProtected(intptr_t addr) {
     // Use a read lock for reading.
-    SYNCHRONIZED_CONST(pages, protectedPages()) {
+    return protectedPages().withRLock([&](auto const& pages) {
       for (const auto& page : pages) {
         intptr_t pageEnd = intptr_t(page + pagesize());
         if (page <= addr && addr < pageEnd) {
           return true;
         }
       }
-    }
       return false;
+    });
   }
 
  private:

folly/fibers/Semaphore.cpp

@@ -20,23 +20,24 @@ namespace fibers {
 
 bool Semaphore::signalSlow() {
   // If we signalled a release, notify the waitlist
-  SYNCHRONIZED(waitList_) {
+  auto waitListLock = waitList_.wlock();
+  auto& waitList = *waitListLock;
+
   auto testVal = tokens_.load(std::memory_order_acquire);
   if (testVal != 0) {
     return false;
   }
 
-    if (waitList_.empty()) {
+  if (waitList.empty()) {
     // If the waitlist is now empty, ensure the token count increments
     // No need for CAS here as we will always be under the mutex
     CHECK(tokens_.compare_exchange_strong(
         testVal, testVal + 1, std::memory_order_relaxed));
   } else {
     // trigger waiter if there is one
-      waitList_.front()->post();
-      waitList_.pop();
+    waitList.front()->post();
+    waitList.pop();
   }
-  } // SYNCHRONIZED(waitList_)
   return true;
 }
 
@@ -59,13 +60,16 @@ bool Semaphore::waitSlow() {
   // Slow path, create a baton and acquire a mutex to update the wait list
   folly::fibers::Baton waitBaton;
 
-  SYNCHRONIZED(waitList_) {
+  {
+    auto waitListLock = waitList_.wlock();
+    auto& waitList = *waitListLock;
+
     auto testVal = tokens_.load(std::memory_order_acquire);
     if (testVal != 0) {
       return false;
     }
     // prepare baton and add to queue
-    waitList_.push(&waitBaton);
+    waitList.push(&waitBaton);
   }
   // If we managed to create a baton, wait on it
   // This has to be done here so the mutex has been released

folly/io/async/EventBaseLocal.cpp

@@ -43,17 +43,13 @@ void EventBaseLocalBase::erase(EventBase& evb) {
   evb.localStorage_.erase(key_);
   evb.localStorageToDtor_.erase(this);
 
-  SYNCHRONIZED(eventBases_) {
-    eventBases_.erase(&evb);
-  }
+  eventBases_.wlock()->erase(&evb);
 }
 
 void EventBaseLocalBase::onEventBaseDestruction(EventBase& evb) {
   evb.dcheckIsInEventBaseThread();
 
-  SYNCHRONIZED(eventBases_) {
-    eventBases_.erase(&evb);
-  }
+  eventBases_.wlock()->erase(&evb);
 }
 
 void EventBaseLocalBase::setVoid(EventBase& evb, std::shared_ptr<void>&& ptr) {