Martin Stjernholm | 4fb5111 | 2021-04-30 11:53:52 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2011 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 ART_LIBARTBASE_BASE_UTILS_H_ |
| 18 | #define ART_LIBARTBASE_BASE_UTILS_H_ |
| 19 | |
| 20 | #include <pthread.h> |
| 21 | #include <stdlib.h> |
| 22 | |
| 23 | #include <random> |
| 24 | #include <string> |
| 25 | |
| 26 | #include <android-base/logging.h> |
| 27 | #include <android-base/parseint.h> |
| 28 | |
| 29 | #include "casts.h" |
| 30 | #include "enums.h" |
| 31 | #include "globals.h" |
| 32 | #include "macros.h" |
| 33 | |
Fairphone ODM | 25c12f5 | 2023-12-15 17:24:06 +0800 | [diff] [blame] | 34 | #if defined(__linux__) |
| 35 | #include <sys/utsname.h> |
| 36 | #endif |
| 37 | |
Martin Stjernholm | 4fb5111 | 2021-04-30 11:53:52 +0100 | [diff] [blame] | 38 | namespace art { |
| 39 | |
| 40 | static inline uint32_t PointerToLowMemUInt32(const void* p) { |
| 41 | uintptr_t intp = reinterpret_cast<uintptr_t>(p); |
| 42 | DCHECK_LE(intp, 0xFFFFFFFFU); |
| 43 | return intp & 0xFFFFFFFFU; |
| 44 | } |
| 45 | |
| 46 | // Returns a human-readable size string such as "1MB". |
| 47 | std::string PrettySize(uint64_t size_in_bytes); |
| 48 | |
| 49 | // Splits a string using the given separator character into a vector of |
| 50 | // strings. Empty strings will be omitted. |
| 51 | template<typename StrIn, typename Str> |
| 52 | void Split(const StrIn& s, char separator, std::vector<Str>* out_result); |
| 53 | |
| 54 | template<typename Str> |
| 55 | void Split(const Str& s, char separator, size_t len, Str* out_result); |
| 56 | |
| 57 | template<typename StrIn, typename Str, size_t kLen> |
| 58 | void Split(const StrIn& s, char separator, std::array<Str, kLen>* out_result) { |
| 59 | Split<Str>(Str(s), separator, kLen, &((*out_result)[0])); |
| 60 | } |
| 61 | |
| 62 | // Returns the calling thread's tid. (The C libraries don't expose this.) |
| 63 | uint32_t GetTid(); |
| 64 | |
| 65 | // Returns the given thread's name. |
| 66 | std::string GetThreadName(pid_t tid); |
| 67 | |
| 68 | // Sets the name of the current thread. The name may be truncated to an |
| 69 | // implementation-defined limit. |
| 70 | void SetThreadName(const char* thread_name); |
| 71 | |
| 72 | // Reads data from "/proc/self/task/${tid}/stat". |
| 73 | void GetTaskStats(pid_t tid, char* state, int* utime, int* stime, int* task_cpu); |
| 74 | |
| 75 | class VoidFunctor { |
| 76 | public: |
| 77 | template <typename A> |
| 78 | inline void operator() (A a ATTRIBUTE_UNUSED) const { |
| 79 | } |
| 80 | |
| 81 | template <typename A, typename B> |
| 82 | inline void operator() (A a ATTRIBUTE_UNUSED, B b ATTRIBUTE_UNUSED) const { |
| 83 | } |
| 84 | |
| 85 | template <typename A, typename B, typename C> |
| 86 | inline void operator() (A a ATTRIBUTE_UNUSED, B b ATTRIBUTE_UNUSED, C c ATTRIBUTE_UNUSED) const { |
| 87 | } |
| 88 | }; |
| 89 | |
| 90 | inline bool TestBitmap(size_t idx, const uint8_t* bitmap) { |
| 91 | return ((bitmap[idx / kBitsPerByte] >> (idx % kBitsPerByte)) & 0x01) != 0; |
| 92 | } |
| 93 | |
| 94 | static inline constexpr bool ValidPointerSize(size_t pointer_size) { |
| 95 | return pointer_size == 4 || pointer_size == 8; |
| 96 | } |
| 97 | |
| 98 | static inline const void* EntryPointToCodePointer(const void* entry_point) { |
| 99 | uintptr_t code = reinterpret_cast<uintptr_t>(entry_point); |
| 100 | // TODO: Make this Thumb2 specific. It is benign on other architectures as code is always at |
| 101 | // least 2 byte aligned. |
| 102 | code &= ~0x1; |
| 103 | return reinterpret_cast<const void*>(code); |
| 104 | } |
| 105 | |
| 106 | #if defined(__BIONIC__) |
| 107 | struct Arc4RandomGenerator { |
Martin Stjernholm | 413b2b5 | 2021-11-15 13:56:19 +0000 | [diff] [blame] | 108 | using result_type = uint32_t; |
Martin Stjernholm | 4fb5111 | 2021-04-30 11:53:52 +0100 | [diff] [blame] | 109 | static constexpr uint32_t min() { return std::numeric_limits<uint32_t>::min(); } |
| 110 | static constexpr uint32_t max() { return std::numeric_limits<uint32_t>::max(); } |
| 111 | uint32_t operator() () { return arc4random(); } |
| 112 | }; |
| 113 | using RNG = Arc4RandomGenerator; |
| 114 | #else |
| 115 | using RNG = std::random_device; |
| 116 | #endif |
| 117 | |
| 118 | template <typename T> |
| 119 | static T GetRandomNumber(T min, T max) { |
| 120 | CHECK_LT(min, max); |
| 121 | std::uniform_int_distribution<T> dist(min, max); |
| 122 | RNG rng; |
| 123 | return dist(rng); |
| 124 | } |
| 125 | |
| 126 | // Sleep forever and never come back. |
| 127 | NO_RETURN void SleepForever(); |
| 128 | |
| 129 | // Flush CPU caches. Returns true on success, false if flush failed. |
| 130 | WARN_UNUSED bool FlushCpuCaches(void* begin, void* end); |
| 131 | |
Fairphone ODM | 25c12f5 | 2023-12-15 17:24:06 +0800 | [diff] [blame] | 132 | #if defined(__linux__) |
| 133 | bool IsKernelVersionAtLeast(int reqd_major, int reqd_minor); |
| 134 | #endif |
| 135 | |
Martin Stjernholm | 4fb5111 | 2021-04-30 11:53:52 +0100 | [diff] [blame] | 136 | // On some old kernels, a cache operation may segfault. |
| 137 | WARN_UNUSED bool CacheOperationsMaySegFault(); |
| 138 | |
| 139 | template <typename T> |
| 140 | constexpr PointerSize ConvertToPointerSize(T any) { |
| 141 | if (any == 4 || any == 8) { |
| 142 | return static_cast<PointerSize>(any); |
| 143 | } else { |
| 144 | LOG(FATAL); |
| 145 | UNREACHABLE(); |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | // Return -1 if <, 0 if ==, 1 if >. |
| 150 | template <typename T> |
| 151 | inline static int32_t Compare(T lhs, T rhs) { |
| 152 | return (lhs < rhs) ? -1 : ((lhs == rhs) ? 0 : 1); |
| 153 | } |
| 154 | |
| 155 | // Return -1 if < 0, 0 if == 0, 1 if > 0. |
| 156 | template <typename T> |
| 157 | inline static int32_t Signum(T opnd) { |
| 158 | return (opnd < 0) ? -1 : ((opnd == 0) ? 0 : 1); |
| 159 | } |
| 160 | |
| 161 | template <typename Func, typename... Args> |
| 162 | static inline void CheckedCall(const Func& function, const char* what, Args... args) { |
| 163 | int rc = function(args...); |
| 164 | if (UNLIKELY(rc != 0)) { |
| 165 | PLOG(FATAL) << "Checked call failed for " << what; |
| 166 | } |
| 167 | } |
| 168 | |
Fairphone ODM | 25c12f5 | 2023-12-15 17:24:06 +0800 | [diff] [blame] | 169 | // Forces the compiler to emit a load instruction, but discards the value. |
| 170 | // Useful when dealing with memory paging. |
| 171 | template <typename T> |
| 172 | inline void ForceRead(const T* pointer) { |
| 173 | static_cast<void>(*const_cast<volatile T*>(pointer)); |
| 174 | } |
| 175 | |
Martin Stjernholm | 4fb5111 | 2021-04-30 11:53:52 +0100 | [diff] [blame] | 176 | // Lookup value for a given key in /proc/self/status. Keys and values are separated by a ':' in |
| 177 | // the status file. Returns value found on success and "<unknown>" if the key is not found or |
| 178 | // there is an I/O error. |
| 179 | std::string GetProcessStatus(const char* key); |
| 180 | |
| 181 | // Return whether the address is guaranteed to be backed by a file or is shared. |
| 182 | // This information can be used to know whether MADV_DONTNEED will make |
| 183 | // following accesses repopulate the memory or return zero. |
| 184 | bool IsAddressKnownBackedByFileOrShared(const void* addr); |
| 185 | |
| 186 | // Returns the number of threads running. |
| 187 | int GetTaskCount(); |
| 188 | |
| 189 | } // namespace art |
| 190 | |
| 191 | #endif // ART_LIBARTBASE_BASE_UTILS_H_ |