platform_system_core/libunwindstack/MemoryCache.h
Peter Collingbourne c71e0a652c libunwindstack: Add Memory::ReadTag() function for reading memory tags.
This uses an experimental Linux kernel API for reading the tags across
processes using ptrace.

Bug: 135772972

Test: Unit tests pass.
Change-Id: Ib1a09d9219166011de80cf250b756bb8a4bcdb0a
2020-04-16 00:23:45 -07:00

51 lines
1.5 KiB
C++

/*
* Copyright (C) 2019 The Android Open Source Project
*
* 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.
*/
#ifndef _LIBUNWINDSTACK_MEMORY_CACHE_H
#define _LIBUNWINDSTACK_MEMORY_CACHE_H
#include <stdint.h>
#include <memory>
#include <string>
#include <unordered_map>
#include <unwindstack/Memory.h>
namespace unwindstack {
class MemoryCache : public Memory {
public:
MemoryCache(Memory* memory) : impl_(memory) {}
virtual ~MemoryCache() = default;
size_t Read(uint64_t addr, void* dst, size_t size) override;
long ReadTag(uint64_t addr) override { return impl_->ReadTag(addr); }
void Clear() override { cache_.clear(); }
private:
constexpr static size_t kCacheBits = 12;
constexpr static size_t kCacheMask = (1 << kCacheBits) - 1;
constexpr static size_t kCacheSize = 1 << kCacheBits;
std::unordered_map<uint64_t, uint8_t[kCacheSize]> cache_;
std::unique_ptr<Memory> impl_;
};
} // namespace unwindstack
#endif // _LIBUNWINDSTACK_MEMORY_CACHE_H