diff options
author | costan <costan@google.com> | 2019-03-11 13:04:53 -0700 |
---|---|---|
committer | Chris Mumford <cmumford@google.com> | 2019-03-11 13:41:25 -0700 |
commit | 7d8e41e49b8fddda66a2c5f0a6a47f1a916e8d26 (patch) | |
tree | 0a5556aaf20ba27bd6ea0ab3792d1366e60b2f81 /port/port_example.h | |
parent | dd906262fd364c08a652dfa914f9995f6b7608a9 (diff) | |
download | leveldb-7d8e41e49b8fddda66a2c5f0a6a47f1a916e8d26.tar.gz |
leveldb: Replace AtomicPointer with std::atomic.
This CL removes AtomicPointer from leveldb's port interface. Its usage is replaced with std::atomic<> from the C++11 standard library.
AtomicPointer was used to wrap flags, numbers, and pointers, so its instances are replaced with std::atomic<bool>, std::atomic<int>, std::atomic<size_t> and std::atomic<Node*>.
This CL does not revise the memory ordering. AtomicPointer's methods are replaced mechanically with their std::atomic equivalents, even when the underlying usage is incorrect. (Example: DBImpl::has_imm_ is written using release stores, even though it is always read using relaxed ordering.) Revising the memory ordering is left for future CLs.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=237865146
Diffstat (limited to 'port/port_example.h')
-rw-r--r-- | port/port_example.h | 29 |
1 files changed, 0 insertions, 29 deletions
diff --git a/port/port_example.h b/port/port_example.h index 9c648c3..1a8fca2 100644 --- a/port/port_example.h +++ b/port/port_example.h @@ -62,35 +62,6 @@ class CondVar { void SignallAll(); }; -// A type that holds a pointer that can be read or written atomically -// (i.e., without word-tearing.) -class AtomicPointer { - private: - intptr_t rep_; - public: - // Initialize to arbitrary value - AtomicPointer(); - - // Initialize to hold v - explicit AtomicPointer(void* v) : rep_(v) { } - - // Read and return the stored pointer with the guarantee that no - // later memory access (read or write) by this thread can be - // reordered ahead of this read. - void* Acquire_Load() const; - - // Set v as the stored pointer with the guarantee that no earlier - // memory access (read or write) by this thread can be reordered - // after this store. - void Release_Store(void* v); - - // Read the stored pointer with no ordering guarantees. - void* NoBarrier_Load() const; - - // Set va as the stored pointer with no ordering guarantees. - void NoBarrier_Store(void* v); -}; - // ------------------ Compression ------------------- // Store the snappy compression of "input[0,input_length-1]" in *output. |