YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.

//  This source code is licensed under the BSD-style license found in the

//  LICENSE file in the root directory of this source tree. An additional grant

//  of patent rights can be found in the PATENTS file in the same directory.

//

// The following only applies to changes made to this file as part of YugaByte development.

//

// Portions Copyright (c) YugaByte, Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except

// in compliance with the License.  You may obtain a copy of the License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software distributed under the License

// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express

// or implied.  See the License for the specific language governing permissions and limitations

// under the License.

//

// Copyright (c) 2011 The LevelDB Authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file. See the AUTHORS file for names of contributors.

#include "yb/rocksdb/util/concurrent_arena.h"

#include <thread>

#include "yb/rocksdb/port/likely.h"

#include "yb/rocksdb/port/port.h"

#include "yb/rocksdb/util/random.h"

#include "yb/gutil/sysinfo.h"

namespace rocksdb {

#if ROCKSDB_SUPPORT_THREAD_LOCAL

__thread uint32_t ConcurrentArena::tls_cpuid = 0;

#endif

ConcurrentArena::ConcurrentArena(size_t block_size, size_t huge_page_size)

    : shard_block_size_(block_size / 8), arena_(block_size, huge_page_size) {

  // find a power of two >= num_cpus and >= 8

  index_mask_ = 7;

  size_t num_cpus = base::NumCPUs();

  while (index_mask_ + 1 < num_cpus) {

    index_mask_ = index_mask_ * 2 + 1;

  }

  shards_.reset(new Shard[index_mask_ + 1]);

  Fixup();

}

ConcurrentArena::Shard* ConcurrentArena::Repick() {

  int cpuid = port::PhysicalCoreID();

  if (UNLIKELY(cpuid < 0)) {

    // cpu id unavailable, just pick randomly

    cpuid =

        Random::GetTLSInstance()->Uniform(static_cast<int>(index_mask_) + 1);

  }

#if ROCKSDB_SUPPORT_THREAD_LOCAL

  // even if we are cpu 0, use a non-zero tls_cpuid so we can tell we

  // have repicked

  tls_cpuid = cpuid | (static_cast<int>(index_mask_) + 1);

#endif

  return &shards_[cpuid & index_mask_];

}

void ConcurrentArena::SetMemTracker(std::shared_ptr<yb::MemTracker> mem_tracker) {

  arena_.SetMemTracker(std::move(mem_tracker));

}

}  // namespace rocksdb