YugabyteDB (2.13.1.0-b60, 21121d69985fbf76aa6958d8f04a9bfa936293b5)

//  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/arena.h"

#include <algorithm>

#ifdef ROCKSDB_MALLOC_USABLE_SIZE

#include <malloc.h>

#endif

#ifndef OS_WIN

#include <sys/mman.h>

#endif

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

#include "yb/rocksdb/env.h"

#include "yb/util/mem_tracker.h"

namespace rocksdb {

// MSVC complains that it is already defined since it is static in the header.

#ifndef OS_WIN

const size_t Arena::kInlineSize;

#endif

const size_t Arena::kMinBlockSize = 4096;

const size_t Arena::kMaxBlockSize = 2 << 30;

static const int kAlignUnit = sizeof(void*);

size_t OptimizeBlockSize(size_t block_size) {

  // Make sure block_size is in optimal range

  block_size = std::max(Arena::kMinBlockSize, block_size);

  block_size = std::min(Arena::kMaxBlockSize, block_size);

  // make sure block_size is the multiple of kAlignUnit

  if (block_size % kAlignUnit != 0) {

    block_size = (1 + block_size / kAlignUnit) * kAlignUnit;

  }

  return block_size;

}

Arena::Arena(size_t block_size, size_t huge_page_size)

    : kBlockSize(OptimizeBlockSize(block_size)) {

  assert(kBlockSize >= kMinBlockSize && kBlockSize <= kMaxBlockSize &&

         kBlockSize % kAlignUnit == 0);

  alloc_bytes_remaining_ = sizeof(inline_block_);

  blocks_memory_ += alloc_bytes_remaining_;

  aligned_alloc_ptr_ = inline_block_;

  unaligned_alloc_ptr_ = inline_block_ + alloc_bytes_remaining_;

#ifdef MAP_HUGETLB

  hugetlb_size_ = huge_page_size;

  if (hugetlb_size_ && kBlockSize > hugetlb_size_) {

    hugetlb_size_ = ((kBlockSize - 1U) / hugetlb_size_ + 1U) * hugetlb_size_;

  }

#endif

}

Arena::~Arena() {

  for (const auto& block : blocks_) {

    delete[] block;

  }

#ifdef MAP_HUGETLB

  for (const auto& mmap_info : huge_blocks_) {

    auto ret = munmap(mmap_info.addr_, mmap_info.length_);

    if (ret != 0) {

      // TODO(sdong): Better handling

    }

  }

#endif

  if (mem_tracker_) {

    mem_tracker_->Release(blocks_memory_);

  }

}

char* Arena::AllocateFallback(size_t bytes, bool aligned) {

  if (bytes > kBlockSize / 4) {

    ++irregular_block_num;

    // Object is more than a quarter of our block size.  Allocate it separately

    // to avoid wasting too much space in leftover bytes.

    return AllocateNewBlock(bytes);

  }

  // We waste the remaining space in the current block.

  size_t size = 0;

  char* block_head = nullptr;

#ifdef MAP_HUGETLB

  if (hugetlb_size_) {

    size = hugetlb_size_;

    block_head = AllocateFromHugePage(size);

  }

#endif

  if (!block_head) {

    size = kBlockSize;

    block_head = AllocateNewBlock(size);

  }

  alloc_bytes_remaining_ = size - bytes;

  if (aligned) {

    aligned_alloc_ptr_ = block_head + bytes;

    unaligned_alloc_ptr_ = block_head + size;

    return block_head;

  } else {

    aligned_alloc_ptr_ = block_head;

    unaligned_alloc_ptr_ = block_head + size - bytes;

    return unaligned_alloc_ptr_;

  }

}

char* Arena::AllocateFromHugePage(size_t bytes) {

#ifdef MAP_HUGETLB

  if (hugetlb_size_ == 0) {

    return nullptr;

  }

  // already reserve space in huge_blocks_ before calling mmap().

  // this way the insertion into the vector below will not throw and we

  // won't leak the mapping in that case. if reserve() throws, we

  // won't leak either

  huge_blocks_.reserve(huge_blocks_.size() + 1);

  void* addr = mmap(nullptr, bytes, (PROT_READ | PROT_WRITE),

                    (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB), 0, 0);

  if (addr == MAP_FAILED) {

    return nullptr;

  }

  // the following shouldn't throw because of the above reserve()

  huge_blocks_.emplace_back(MmapInfo(addr, bytes));

  return reinterpret_cast<char*>(addr);

#else

  return nullptr;

#endif

}

char* Arena::AllocateAligned(size_t bytes, size_t huge_page_size,

                             Logger* logger) {

  assert((kAlignUnit & (kAlignUnit - 1)) ==

         0);  // Pointer size should be a power of 2

#ifdef MAP_HUGETLB

  if (huge_page_size > 0 && bytes > 0) {

    // Allocate from a huge page TBL table.

    assert(logger != nullptr);  // logger need to be passed in.

    size_t reserved_size =

        ((bytes - 1U) / huge_page_size + 1U) * huge_page_size;

    assert(reserved_size >= bytes);

    char* addr = AllocateFromHugePage(reserved_size);

    if (addr == nullptr) {

      RWARN(logger, "AllocateAligned fail to allocate huge TLB pages: %s",

           strerror(errno));

      // fail back to malloc

    } else {

      return addr;

    }

  }

#endif

  size_t current_mod =

      reinterpret_cast<uintptr_t>(aligned_alloc_ptr_) & (kAlignUnit - 1);

  size_t slop = (current_mod == 0 ? 
0587M
 : 
kAlignUnit - current_mod2.38M
);

  size_t needed = bytes + slop;

  char* result;

  if (needed <= alloc_bytes_remaining_) {

    result = aligned_alloc_ptr_ + slop;

    aligned_alloc_ptr_ += needed;

    alloc_bytes_remaining_ -= needed;

  } else {

    // AllocateFallback always returns aligned memory

    result = AllocateFallback(bytes, true /* aligned */);

  }

  assert((reinterpret_cast<uintptr_t>(result) & (kAlignUnit - 1)) == 0);

  return result;

}

char* Arena::AllocateNewBlock(size_t block_bytes) {

  // already reserve space in blocks_ before allocating memory via new.

  // this way the insertion into the vector below will not throw and we

  // won't leak the allocated memory in that case. if reserve() throws,

  // we won't leak either

  blocks_.reserve(blocks_.size() + 1);

  char* block = new char[block_bytes];

#ifdef ROCKSDB_MALLOC_USABLE_SIZE

  Consumed(malloc_usable_size(block));

#else

  Consumed(block_bytes);

#endif  // ROCKSDB_MALLOC_USABLE_SIZE

  // the following shouldn't throw because of the above reserve()

  blocks_.push_back(block);

  return block;

}

void Arena::Consumed(size_t size) {

  blocks_memory_ += size;

  if (mem_tracker_) {

    mem_tracker_->Consume(size);

  }

}

void Arena::SetMemTracker(yb::MemTrackerPtr mem_tracker) {

  mem_tracker_ = std::move(mem_tracker);

  mem_tracker_->Consume(blocks_memory_);

}

}  // namespace rocksdb