folly::CoreCachedSharedPtr< T, kNumSlots > Class Template Reference

#include <CoreCachedSharedPtr.h>

Public Member Functions
	CoreCachedSharedPtr (const std::shared_ptr< T > &p=nullptr)
void	reset (const std::shared_ptr< T > &p=nullptr)
std::shared_ptr< T >	get () const

Private Types
using	Holder = std::shared_ptr< T >

Private Attributes
std::array< std::shared_ptr< T >, kNumSlots >	slots_

Friends
template<class , size_t >
class	CoreCachedWeakPtr

Detailed Description

template<class T, size_t kNumSlots = 64>
class folly::CoreCachedSharedPtr< T, kNumSlots >

This class creates core-local caches for a given shared_ptr, to mitigate contention when acquiring/releasing it.

It has the same thread-safety guarantees as shared_ptr: it is safe to concurrently call get(), but reset()s must be synchronized with reads and other resets().

Author

Giuseppe Ottaviano ott@f.nosp@m.b.co.nosp@m.m

Definition at line 40 of file CoreCachedSharedPtr.h.

Member Typedef Documentation

template<class T, size_t kNumSlots = 64>

using folly::CoreCachedSharedPtr< T, kNumSlots >::Holder = std::shared_ptr<T>

private

Definition at line 62 of file CoreCachedSharedPtr.h.

Constructor & Destructor Documentation

template<class T, size_t kNumSlots = 64>

folly::CoreCachedSharedPtr< T, kNumSlots >::CoreCachedSharedPtr ( const std::shared_ptr< T > &  p = nullptr )

inlineexplicit

Definition at line 42 of file CoreCachedSharedPtr.h.

References folly::CoreCachedSharedPtr< T, kNumSlots >::reset().

                                                                    {
    reset(p);
  }

Member Function Documentation

template<class T, size_t kNumSlots = 64>

std::shared_ptr<T> folly::CoreCachedSharedPtr< T, kNumSlots >::get ( ) const

inline

Definition at line 57 of file CoreCachedSharedPtr.h.

References folly::AccessSpreader< Atom >::current(), and folly::CoreCachedSharedPtr< T, kNumSlots >::slots_.

                               {
    return slots_[AccessSpreader<>::current(kNumSlots)];
  }

template<class T, size_t kNumSlots = 64>

void folly::CoreCachedSharedPtr< T, kNumSlots >::reset ( const std::shared_ptr< T > &  p = nullptr )

inline

Definition at line 46 of file CoreCachedSharedPtr.h.

References folly::enumerate(), and folly::CoreCachedSharedPtr< T, kNumSlots >::slots_.

Referenced by folly::AtomicCoreCachedSharedPtr< T, kNumSlots >::AtomicCoreCachedSharedPtr(), and folly::CoreCachedSharedPtr< T, kNumSlots >::CoreCachedSharedPtr().

                                                  {
    // Allocate each Holder in a different CoreRawAllocator stripe to
    // prevent false sharing. Their control blocks will be adjacent
    // thanks to allocate_shared().
    for (auto slot : folly::enumerate(slots_)) {
      auto alloc = getCoreAllocator<Holder, kNumSlots>(slot.index);
      auto holder = std::allocate_shared<Holder>(alloc, p);
      *slot = std::shared_ptr<T>(holder, p.get());
    }
  }

Friends And Related Function Documentation

template<class T, size_t kNumSlots = 64>

template<class , size_t >

friend class CoreCachedWeakPtr

friend

Definition at line 65 of file CoreCachedSharedPtr.h.

Member Data Documentation

template<class T, size_t kNumSlots = 64>

std::array<std::shared_ptr<T>, kNumSlots> folly::CoreCachedSharedPtr< T, kNumSlots >::slots_

private

Definition at line 67 of file CoreCachedSharedPtr.h.

Referenced by folly::CoreCachedWeakPtr< T, kNumSlots >::CoreCachedWeakPtr(), folly::CoreCachedSharedPtr< T, kNumSlots >::get(), folly::CoreCachedWeakPtr< T, kNumSlots >::get(), folly::AtomicCoreCachedSharedPtr< T, kNumSlots >::get(), folly::CoreCachedSharedPtr< T, kNumSlots >::reset(), folly::AtomicCoreCachedSharedPtr< T, kNumSlots >::reset(), and folly::AtomicCoreCachedSharedPtr< T, kNumSlots >::~AtomicCoreCachedSharedPtr().

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The documentation for this class was generated from the following file:

• proxygen/folly/folly/concurrency/CoreCachedSharedPtr.h