constexpr_log2_ceil

[folly.git] / folly / SharedMutex.h

diff --git a/folly/SharedMutex.h b/folly/SharedMutex.h
index 163382ab34b8155dc7e0b60cd95f23ef4af76ce5..ce160f8087a99a1d7bdfab51fc5e2c040d3a6dbc 100644 (file)
--- a/folly/SharedMutex.h
+++ b/folly/SharedMutex.h
@@ -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;
@@ -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;
@@ -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,