rocksdb/util/jemalloc_nodump_allocator.h
Yi Wu 5f5fddabc7 port folly::JemallocNodumpAllocator (#4534)
Summary:
Introduce `JemallocNodumpAllocator`, which allow exclusion of block cache usage from core dump. It utilize custom hook of jemalloc arena, and when jemalloc arena request memory from system, the allocator use the hook to set `MADV_DONTDUMP ` to the memory. The implementation is basically the same as `folly::JemallocNodumpAllocator`, except for some minor difference:
1. It only support jemalloc >= 5.0
2. When the allocator destruct, it explicitly destruct the corresponding arena via `arena.<i>.destroy` via `mallctl`.

Depending on #4502.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4534

Differential Revision: D10435474

Pulled By: yiwu-arbug

fbshipit-source-id: e80edea755d3853182485d2be710376384ce0bb4
2018-10-26 17:29:18 -07:00

57 lines
1.9 KiB
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).
#pragma once
#include <atomic>
#include "rocksdb/memory_allocator.h"
#if defined(ROCKSDB_JEMALLOC) && defined(ROCKSDB_PLATFORM_POSIX)
#include <jemalloc/jemalloc.h>
#include <sys/mman.h>
#if (JEMALLOC_VERSION_MAJOR >= 5) && defined(MADV_DONTDUMP)
#define ROCKSDB_JEMALLOC_NODUMP_ALLOCATOR
namespace rocksdb {
class JemallocNodumpAllocator : public MemoryAllocator {
public:
JemallocNodumpAllocator(unsigned arena_index, int flags,
std::unique_ptr<extent_hooks_t>&& hooks);
~JemallocNodumpAllocator();
const char* Name() const override { return "JemallocNodumpAllocator"; }
void* Allocate(size_t size) override;
void Deallocate(void* p) override;
size_t UsableSize(void* p, size_t allocation_size) const override;
private:
friend Status NewJemallocNodumpAllocator(
std::shared_ptr<MemoryAllocator>* memory_allocator);
// Custom alloc hook to replace jemalloc default alloc.
static void* Alloc(extent_hooks_t* extent, void* new_addr, size_t size,
size_t alignment, bool* zero, bool* commit,
unsigned arena_ind);
// A function pointer to jemalloc default alloc. Use atomic to make sure
// NewJemallocNodumpAllocator is thread-safe.
//
// Hack: original_alloc_ needs to be static for Alloc() to access it.
// alloc needs to be static to pass to jemalloc as function pointer.
static std::atomic<extent_alloc_t*> original_alloc_;
unsigned arena_index_;
int flags_;
const std::unique_ptr<extent_hooks_t> hooks_;
};
} // namespace rocksdb
#endif // (JEMALLOC_VERSION_MAJOR >= 5) && MADV_DONTDUMP
#endif // ROCKSDB_JEMALLOC && ROCKSDB_PLATFORM_POSIX