mirror of
https://github.com/facebook/rocksdb.git
synced 2024-11-26 07:30:54 +00:00
3c327ac2d0
Summary: Closes https://github.com/facebook/rocksdb/pull/2589 Differential Revision: D5431502 Pulled By: siying fbshipit-source-id: 8ebf8c87883daa9daa54b2303d11ce01ab1f6f75
39 lines
975 B
C++
39 lines
975 B
C++
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under both the GPLv2 (found in the
|
|
// COPYING file in the root directory) and Apache 2.0 License
|
|
// (found in the LICENSE.Apache file in the root directory).
|
|
//
|
|
|
|
#include "util/random.h"
|
|
|
|
#include <stdint.h>
|
|
#include <string.h>
|
|
#include <thread>
|
|
#include <utility>
|
|
|
|
#include "port/likely.h"
|
|
#include "util/thread_local.h"
|
|
|
|
#ifdef ROCKSDB_SUPPORT_THREAD_LOCAL
|
|
#define STORAGE_DECL static __thread
|
|
#else
|
|
#define STORAGE_DECL static
|
|
#endif
|
|
|
|
namespace rocksdb {
|
|
|
|
Random* Random::GetTLSInstance() {
|
|
STORAGE_DECL Random* tls_instance;
|
|
STORAGE_DECL std::aligned_storage<sizeof(Random)>::type tls_instance_bytes;
|
|
|
|
auto rv = tls_instance;
|
|
if (UNLIKELY(rv == nullptr)) {
|
|
size_t seed = std::hash<std::thread::id>()(std::this_thread::get_id());
|
|
rv = new (&tls_instance_bytes) Random((uint32_t)seed);
|
|
tls_instance = rv;
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
} // namespace rocksdb
|