Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2016 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef LIBMEMUNREACHABLE_HEAP_WALKER_H_ |
| 18 | #define LIBMEMUNREACHABLE_HEAP_WALKER_H_ |
| 19 | |
Colin Cross | 1369ba4 | 2016-04-26 16:51:32 -0700 | [diff] [blame] | 20 | #include <signal.h> |
| 21 | |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 22 | #include "android-base/macros.h" |
| 23 | |
| 24 | #include "Allocator.h" |
Colin Cross | 1369ba4 | 2016-04-26 16:51:32 -0700 | [diff] [blame] | 25 | #include "ScopedSignalHandler.h" |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 26 | #include "Tarjan.h" |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 27 | |
Colin Cross | 1fa81f5 | 2017-06-21 13:13:00 -0700 | [diff] [blame] | 28 | namespace android { |
| 29 | |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 30 | // A range [begin, end) |
| 31 | struct Range { |
| 32 | uintptr_t begin; |
| 33 | uintptr_t end; |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 34 | |
| 35 | size_t size() const { return end - begin; }; |
Colin Cross | 0b631e7 | 2016-04-26 17:10:04 -0700 | [diff] [blame] | 36 | bool operator==(const Range& other) const { |
| 37 | return this->begin == other.begin && this->end == other.end; |
| 38 | } |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 39 | bool operator!=(const Range& other) const { return !(*this == other); } |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 40 | }; |
| 41 | |
| 42 | // Comparator for Ranges that returns equivalence for overlapping ranges |
| 43 | struct compare_range { |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 44 | bool operator()(const Range& a, const Range& b) const { return a.end <= b.begin; } |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 45 | }; |
| 46 | |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 47 | class HeapWalker { |
| 48 | public: |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 49 | explicit HeapWalker(Allocator<HeapWalker> allocator) |
| 50 | : allocator_(allocator), |
| 51 | allocations_(allocator), |
| 52 | allocation_bytes_(0), |
| 53 | roots_(allocator), |
| 54 | root_vals_(allocator), |
Pirama Arumuga Nainar | 2583afd | 2018-09-26 09:00:24 -0700 | [diff] [blame] | 55 | segv_handler_(), |
Colin Cross | c2c76d4 | 2018-11-27 16:14:53 -0800 | [diff] [blame] | 56 | walking_ptr_(0), |
| 57 | walking_range_{0, 0}, |
| 58 | segv_logged_(false), |
| 59 | segv_page_count_(0) { |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 60 | valid_allocations_range_.end = 0; |
| 61 | valid_allocations_range_.begin = ~valid_allocations_range_.end; |
Colin Cross | 223069f | 2018-11-28 17:01:59 -0800 | [diff] [blame^] | 62 | valid_mappings_range_.end = 0; |
| 63 | valid_mappings_range_.begin = ~valid_allocations_range_.end; |
Colin Cross | 1369ba4 | 2016-04-26 16:51:32 -0700 | [diff] [blame] | 64 | |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 65 | segv_handler_.install( |
| 66 | SIGSEGV, [=](ScopedSignalHandler& handler, int signal, siginfo_t* siginfo, void* uctx) { |
Colin Cross | 1369ba4 | 2016-04-26 16:51:32 -0700 | [diff] [blame] | 67 | this->HandleSegFault(handler, signal, siginfo, uctx); |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 68 | }); |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 69 | } |
Colin Cross | 1369ba4 | 2016-04-26 16:51:32 -0700 | [diff] [blame] | 70 | |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 71 | ~HeapWalker() {} |
| 72 | bool Allocation(uintptr_t begin, uintptr_t end); |
Colin Cross | 223069f | 2018-11-28 17:01:59 -0800 | [diff] [blame^] | 73 | void Mapping(uintptr_t begin, uintptr_t end); |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 74 | void Root(uintptr_t begin, uintptr_t end); |
| 75 | void Root(const allocator::vector<uintptr_t>& vals); |
| 76 | |
| 77 | bool DetectLeaks(); |
| 78 | |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 79 | bool Leaked(allocator::vector<Range>&, size_t limit, size_t* num_leaks, size_t* leak_bytes); |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 80 | size_t Allocations(); |
| 81 | size_t AllocationBytes(); |
| 82 | |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 83 | template <class F> |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 84 | void ForEachPtrInRange(const Range& range, F&& f); |
| 85 | |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 86 | template <class F> |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 87 | void ForEachAllocation(F&& f); |
| 88 | |
| 89 | struct AllocationInfo { |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 90 | bool referenced_from_root; |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 91 | }; |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 92 | |
| 93 | private: |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 94 | void RecurseRoot(const Range& root); |
Colin Cross | 1369ba4 | 2016-04-26 16:51:32 -0700 | [diff] [blame] | 95 | bool WordContainsAllocationPtr(uintptr_t ptr, Range* range, AllocationInfo** info); |
| 96 | void HandleSegFault(ScopedSignalHandler&, int, siginfo_t*, void*); |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 97 | |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 98 | DISALLOW_COPY_AND_ASSIGN(HeapWalker); |
| 99 | Allocator<HeapWalker> allocator_; |
Colin Cross | 20774fc | 2016-03-04 16:34:42 -0800 | [diff] [blame] | 100 | using AllocationMap = allocator::map<Range, AllocationInfo, compare_range>; |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 101 | AllocationMap allocations_; |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 102 | size_t allocation_bytes_; |
| 103 | Range valid_allocations_range_; |
Colin Cross | 223069f | 2018-11-28 17:01:59 -0800 | [diff] [blame^] | 104 | Range valid_mappings_range_; |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 105 | |
| 106 | allocator::vector<Range> roots_; |
| 107 | allocator::vector<uintptr_t> root_vals_; |
Colin Cross | 1369ba4 | 2016-04-26 16:51:32 -0700 | [diff] [blame] | 108 | |
| 109 | ScopedSignalHandler segv_handler_; |
Colin Cross | c2c76d4 | 2018-11-27 16:14:53 -0800 | [diff] [blame] | 110 | volatile uintptr_t walking_ptr_; |
| 111 | Range walking_range_; |
| 112 | bool segv_logged_; |
| 113 | size_t segv_page_count_; |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 114 | }; |
| 115 | |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 116 | template <class F> |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 117 | inline void HeapWalker::ForEachPtrInRange(const Range& range, F&& f) { |
| 118 | uintptr_t begin = (range.begin + (sizeof(uintptr_t) - 1)) & ~(sizeof(uintptr_t) - 1); |
| 119 | // TODO(ccross): we might need to consider a pointer to the end of a buffer |
| 120 | // to be inside the buffer, which means the common case of a pointer to the |
| 121 | // beginning of a buffer may keep two ranges live. |
| 122 | for (uintptr_t i = begin; i < range.end; i += sizeof(uintptr_t)) { |
| 123 | Range ref_range; |
| 124 | AllocationInfo* ref_info; |
Colin Cross | 1369ba4 | 2016-04-26 16:51:32 -0700 | [diff] [blame] | 125 | if (WordContainsAllocationPtr(i, &ref_range, &ref_info)) { |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 126 | f(ref_range, ref_info); |
| 127 | } |
| 128 | } |
| 129 | } |
| 130 | |
Colin Cross | 401319a | 2017-06-22 10:50:05 -0700 | [diff] [blame] | 131 | template <class F> |
Colin Cross | eccc5e4 | 2016-03-02 17:53:39 -0800 | [diff] [blame] | 132 | inline void HeapWalker::ForEachAllocation(F&& f) { |
| 133 | for (auto& it : allocations_) { |
| 134 | const Range& range = it.first; |
| 135 | HeapWalker::AllocationInfo& allocation = it.second; |
| 136 | f(range, allocation); |
| 137 | } |
| 138 | } |
| 139 | |
Colin Cross | 1fa81f5 | 2017-06-21 13:13:00 -0700 | [diff] [blame] | 140 | } // namespace android |
| 141 | |
Colin Cross | ab7c9f1 | 2016-01-14 15:35:40 -0800 | [diff] [blame] | 142 | #endif |