cmake: fix path to FindGLog.cmake

[folly.git] / folly / SharedMutex.h

diff --git a/folly/SharedMutex.h b/folly/SharedMutex.h
index 24d8051c4d5e81780610a4d5c83b8084298f6766..65baec0abe58c7382f25dce496d0e49476a3d068 100644 (file)
--- a/folly/SharedMutex.h
+++ b/folly/SharedMutex.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Facebook, Inc.
+ * Copyright 2015-present Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -236,10 +236,11 @@ struct SharedMutexToken {
   uint16_t slot_;
 };
 
-template <bool ReaderPriority,
-          typename Tag_ = void,
-          template <typename> class Atom = std::atomic,
-          bool BlockImmediately = false>
+template <
+    bool ReaderPriority,
+    typename Tag_ = void,
+    template <typename> class Atom = std::atomic,
+    bool BlockImmediately = false>
 class SharedMutexImpl {
  public:
   static constexpr bool kReaderPriority = ReaderPriority;
@@ -562,7 +563,7 @@ class SharedMutexImpl {
   };
 
   // 32 bits of state
-  Futex state_;
+  Futex state_{};
 
   // S count needs to be on the end, because we explicitly allow it to
   // underflow.  This can occur while we are in the middle of applying
@@ -737,9 +738,8 @@ class SharedMutexImpl {
   typedef Atom<uintptr_t> DeferredReaderSlot;
 
  private:
-  FOLLY_ALIGN_TO_AVOID_FALSE_SHARING static DeferredReaderSlot deferredReaders
-      [kMaxDeferredReaders *
-       kDeferredSeparationFactor];
+  alignas(hardware_destructive_interference_size) static DeferredReaderSlot
+      deferredReaders[kMaxDeferredReaders * kDeferredSeparationFactor];
 
   // Performs an exclusive lock, waiting for state_ & waitMask to be
   // zero first
@@ -849,6 +849,7 @@ class SharedMutexImpl {
                             WaitContext& ctx) {
 #ifdef RUSAGE_THREAD
     struct rusage usage;
+    std::memset(&usage, 0, sizeof(usage));
     long before = -1;
 #endif
     for (uint32_t yieldCount = 0; yieldCount < kMaxSoftYieldCount;
@@ -991,7 +992,7 @@ class SharedMutexImpl {
           return;
         }
       }
-      asm_pause();
+      asm_volatile_pause();
       if (UNLIKELY(++spinCount >= kMaxSpinCount)) {
         applyDeferredReaders(state, ctx, slot);
         return;
@@ -1004,6 +1005,7 @@ class SharedMutexImpl {
 
 #ifdef RUSAGE_THREAD
     struct rusage usage;
+    std::memset(&usage, 0, sizeof(usage));
     long before = -1;
 #endif
     for (uint32_t yieldCount = 0; yieldCount < kMaxSoftYieldCount;
@@ -1347,11 +1349,11 @@ template <
     typename Tag_,
     template <typename> class Atom,
     bool BlockImmediately>
-typename SharedMutexImpl<ReaderPriority, Tag_, Atom, BlockImmediately>::
-    DeferredReaderSlot
-        SharedMutexImpl<ReaderPriority, Tag_, Atom, BlockImmediately>::
-            deferredReaders[kMaxDeferredReaders * kDeferredSeparationFactor] =
-                {};
+alignas(hardware_destructive_interference_size)
+    typename SharedMutexImpl<ReaderPriority, Tag_, Atom, BlockImmediately>::
+        DeferredReaderSlot
+    SharedMutexImpl<ReaderPriority, Tag_, Atom, BlockImmediately>::
+        deferredReaders[kMaxDeferredReaders * kDeferredSeparationFactor] = {};
 
 template <
     bool ReaderPriority,