1 /*
2 * Copyright (C) 2015 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 #include "dso.h"
18
19 #include <stdlib.h>
20 #include <string.h>
21
22 #include <algorithm>
23 #include <limits>
24 #include <memory>
25 #include <vector>
26
27 #include <android-base/file.h>
28 #include <android-base/logging.h>
29 #include <android-base/strings.h>
30
31 #include "environment.h"
32 #include "read_apk.h"
33 #include "read_dex_file.h"
34 #include "read_elf.h"
35 #include "utils.h"
36
37 namespace simpleperf_dso_impl {
38
RemovePathSeparatorSuffix(const std::string & path)39 std::string RemovePathSeparatorSuffix(const std::string& path) {
40 // Don't remove path separator suffix for '/'.
41 if (android::base::EndsWith(path, OS_PATH_SEPARATOR) && path.size() > 1u) {
42 return path.substr(0, path.size() - 1);
43 }
44 return path;
45 }
46
Reset()47 void DebugElfFileFinder::Reset() {
48 vdso_64bit_.clear();
49 vdso_32bit_.clear();
50 symfs_dir_.clear();
51 build_id_to_file_map_.clear();
52 }
53
SetSymFsDir(const std::string & symfs_dir)54 bool DebugElfFileFinder::SetSymFsDir(const std::string& symfs_dir) {
55 symfs_dir_ = RemovePathSeparatorSuffix(symfs_dir);
56 if (!IsDir(symfs_dir_)) {
57 LOG(ERROR) << "Invalid symfs_dir '" << symfs_dir_ << "'";
58 return false;
59 }
60 std::string build_id_list_file = symfs_dir_ + OS_PATH_SEPARATOR + "build_id_list";
61 std::string build_id_list;
62 if (android::base::ReadFileToString(build_id_list_file, &build_id_list)) {
63 for (auto& line : android::base::Split(build_id_list, "\n")) {
64 std::vector<std::string> items = android::base::Split(line, "=");
65 if (items.size() == 2u) {
66 build_id_to_file_map_[items[0]] = symfs_dir_ + OS_PATH_SEPARATOR + items[1];
67 }
68 }
69 }
70 return true;
71 }
72
AddSymbolDir(const std::string & symbol_dir)73 bool DebugElfFileFinder::AddSymbolDir(const std::string& symbol_dir) {
74 if (!IsDir(symbol_dir)) {
75 LOG(ERROR) << "Invalid symbol dir " << symbol_dir;
76 return false;
77 }
78 std::string dir = RemovePathSeparatorSuffix(symbol_dir);
79 CollectBuildIdInDir(dir);
80 return true;
81 }
82
CollectBuildIdInDir(const std::string & dir)83 void DebugElfFileFinder::CollectBuildIdInDir(const std::string& dir) {
84 for (const std::string& entry : GetEntriesInDir(dir)) {
85 std::string path = dir + OS_PATH_SEPARATOR + entry;
86 if (IsDir(path)) {
87 CollectBuildIdInDir(path);
88 } else {
89 BuildId build_id;
90 if (GetBuildIdFromElfFile(path, &build_id) == ElfStatus::NO_ERROR) {
91 build_id_to_file_map_[build_id.ToString()] = path;
92 }
93 }
94 }
95 }
96
SetVdsoFile(const std::string & vdso_file,bool is_64bit)97 void DebugElfFileFinder::SetVdsoFile(const std::string& vdso_file, bool is_64bit) {
98 if (is_64bit) {
99 vdso_64bit_ = vdso_file;
100 } else {
101 vdso_32bit_ = vdso_file;
102 }
103 }
104
FindDebugFile(const std::string & dso_path,bool force_64bit,BuildId & build_id)105 std::string DebugElfFileFinder::FindDebugFile(const std::string& dso_path, bool force_64bit,
106 BuildId& build_id) {
107 if (dso_path == "[vdso]") {
108 if (force_64bit && !vdso_64bit_.empty()) {
109 return vdso_64bit_;
110 } else if (!force_64bit && !vdso_32bit_.empty()) {
111 return vdso_32bit_;
112 }
113 }
114 // 1. Try build_id_to_file_map.
115 if (!build_id_to_file_map_.empty()) {
116 if (!build_id.IsEmpty() || GetBuildIdFromDsoPath(dso_path, &build_id)) {
117 auto it = build_id_to_file_map_.find(build_id.ToString());
118 if (it != build_id_to_file_map_.end()) {
119 return it->second;
120 }
121 }
122 }
123 auto check_path = [&](const std::string& path) {
124 BuildId debug_build_id;
125 if (GetBuildIdFromDsoPath(path, &debug_build_id)) {
126 if (!build_id.IsEmpty() || GetBuildIdFromDsoPath(dso_path, &build_id)) {
127 if (build_id == debug_build_id) {
128 return true;
129 }
130 }
131 }
132 return false;
133 };
134
135 // 2. Try concatenating symfs_dir and dso_path.
136 if (!symfs_dir_.empty()) {
137 std::string path = GetPathInSymFsDir(dso_path);
138 if (check_path(path)) {
139 return path;
140 }
141 }
142 // 3. Try concatenating /usr/lib/debug and dso_path.
143 // Linux host can store debug shared libraries in /usr/lib/debug.
144 if (check_path("/usr/lib/debug" + dso_path)) {
145 return "/usr/lib/debug" + dso_path;
146 }
147 return dso_path;
148 }
149
GetPathInSymFsDir(const std::string & path)150 std::string DebugElfFileFinder::GetPathInSymFsDir(const std::string& path) {
151 auto add_symfs_prefix = [&](const std::string& path) {
152 if (android::base::StartsWith(path, OS_PATH_SEPARATOR)) {
153 return symfs_dir_ + path;
154 }
155 return symfs_dir_ + OS_PATH_SEPARATOR + path;
156 };
157 if (OS_PATH_SEPARATOR == '/') {
158 return add_symfs_prefix(path);
159 }
160 // Paths in recorded perf.data uses '/' as path separator. When reporting on Windows, it needs
161 // to be converted to '\\'.
162 auto tuple = SplitUrlInApk(path);
163 if (std::get<0>(tuple)) {
164 std::string apk_path = std::get<1>(tuple);
165 std::string entry_path = std::get<2>(tuple);
166 std::replace(apk_path.begin(), apk_path.end(), '/', OS_PATH_SEPARATOR);
167 return GetUrlInApk(add_symfs_prefix(apk_path), entry_path);
168 }
169 std::string elf_path = path;
170 std::replace(elf_path.begin(), elf_path.end(), '/', OS_PATH_SEPARATOR);
171 return add_symfs_prefix(elf_path);
172 }
173 } // namespace simpleperf_dso_imp
174
175 static OneTimeFreeAllocator symbol_name_allocator;
176
Symbol(std::string_view name,uint64_t addr,uint64_t len)177 Symbol::Symbol(std::string_view name, uint64_t addr, uint64_t len)
178 : addr(addr),
179 len(len),
180 name_(symbol_name_allocator.AllocateString(name)),
181 demangled_name_(nullptr),
182 dump_id_(UINT_MAX) {
183 }
184
DemangledName() const185 const char* Symbol::DemangledName() const {
186 if (demangled_name_ == nullptr) {
187 const std::string s = Dso::Demangle(name_);
188 if (s == name_) {
189 demangled_name_ = name_;
190 } else {
191 demangled_name_ = symbol_name_allocator.AllocateString(s);
192 }
193 }
194 return demangled_name_;
195 }
196
197 bool Dso::demangle_ = true;
198 std::string Dso::vmlinux_;
199 std::string Dso::kallsyms_;
200 bool Dso::read_kernel_symbols_from_proc_;
201 std::unordered_map<std::string, BuildId> Dso::build_id_map_;
202 size_t Dso::dso_count_;
203 uint32_t Dso::g_dump_id_;
204 simpleperf_dso_impl::DebugElfFileFinder Dso::debug_elf_file_finder_;
205
SetDemangle(bool demangle)206 void Dso::SetDemangle(bool demangle) { demangle_ = demangle; }
207
208 extern "C" char* __cxa_demangle(const char* mangled_name, char* buf, size_t* n,
209 int* status);
210
Demangle(const std::string & name)211 std::string Dso::Demangle(const std::string& name) {
212 if (!demangle_) {
213 return name;
214 }
215 int status;
216 bool is_linker_symbol = (name.find(linker_prefix) == 0);
217 const char* mangled_str = name.c_str();
218 if (is_linker_symbol) {
219 mangled_str += linker_prefix.size();
220 }
221 std::string result = name;
222 char* demangled_name = __cxa_demangle(mangled_str, nullptr, nullptr, &status);
223 if (status == 0) {
224 if (is_linker_symbol) {
225 result = std::string("[linker]") + demangled_name;
226 } else {
227 result = demangled_name;
228 }
229 free(demangled_name);
230 } else if (is_linker_symbol) {
231 result = std::string("[linker]") + mangled_str;
232 }
233 return result;
234 }
235
SetSymFsDir(const std::string & symfs_dir)236 bool Dso::SetSymFsDir(const std::string& symfs_dir) {
237 return debug_elf_file_finder_.SetSymFsDir(symfs_dir);
238 }
239
AddSymbolDir(const std::string & symbol_dir)240 bool Dso::AddSymbolDir(const std::string& symbol_dir) {
241 return debug_elf_file_finder_.AddSymbolDir(symbol_dir);
242 }
243
SetVmlinux(const std::string & vmlinux)244 void Dso::SetVmlinux(const std::string& vmlinux) { vmlinux_ = vmlinux; }
245
SetBuildIds(const std::vector<std::pair<std::string,BuildId>> & build_ids)246 void Dso::SetBuildIds(
247 const std::vector<std::pair<std::string, BuildId>>& build_ids) {
248 std::unordered_map<std::string, BuildId> map;
249 for (auto& pair : build_ids) {
250 LOG(DEBUG) << "build_id_map: " << pair.first << ", "
251 << pair.second.ToString();
252 map.insert(pair);
253 }
254 build_id_map_ = std::move(map);
255 }
256
SetVdsoFile(const std::string & vdso_file,bool is_64bit)257 void Dso::SetVdsoFile(const std::string& vdso_file, bool is_64bit) {
258 debug_elf_file_finder_.SetVdsoFile(vdso_file, is_64bit);
259 }
260
FindExpectedBuildIdForPath(const std::string & path)261 BuildId Dso::FindExpectedBuildIdForPath(const std::string& path) {
262 auto it = build_id_map_.find(path);
263 if (it != build_id_map_.end()) {
264 return it->second;
265 }
266 return BuildId();
267 }
268
GetExpectedBuildId()269 BuildId Dso::GetExpectedBuildId() {
270 return FindExpectedBuildIdForPath(path_);
271 }
272
Dso(DsoType type,const std::string & path,const std::string & debug_file_path)273 Dso::Dso(DsoType type, const std::string& path, const std::string& debug_file_path)
274 : type_(type),
275 path_(path),
276 debug_file_path_(debug_file_path),
277 is_loaded_(false),
278 dump_id_(UINT_MAX),
279 symbol_dump_id_(0),
280 symbol_warning_loglevel_(android::base::WARNING) {
281 size_t pos = path.find_last_of("/\\");
282 if (pos != std::string::npos) {
283 file_name_ = path.substr(pos + 1);
284 } else {
285 file_name_ = path;
286 }
287 dso_count_++;
288 }
289
~Dso()290 Dso::~Dso() {
291 if (--dso_count_ == 0) {
292 // Clean up global variables when no longer used.
293 symbol_name_allocator.Clear();
294 demangle_ = true;
295 vmlinux_.clear();
296 kallsyms_.clear();
297 read_kernel_symbols_from_proc_ = false;
298 build_id_map_.clear();
299 g_dump_id_ = 0;
300 debug_elf_file_finder_.Reset();
301 }
302 }
303
CreateDumpId()304 uint32_t Dso::CreateDumpId() {
305 CHECK(!HasDumpId());
306 return dump_id_ = g_dump_id_++;
307 }
308
CreateSymbolDumpId(const Symbol * symbol)309 uint32_t Dso::CreateSymbolDumpId(const Symbol* symbol) {
310 CHECK(!symbol->HasDumpId());
311 symbol->dump_id_ = symbol_dump_id_++;
312 return symbol->dump_id_;
313 }
314
FindSymbol(uint64_t vaddr_in_dso)315 const Symbol* Dso::FindSymbol(uint64_t vaddr_in_dso) {
316 if (!is_loaded_) {
317 Load();
318 }
319 auto it = std::upper_bound(symbols_.begin(), symbols_.end(),
320 Symbol("", vaddr_in_dso, 0),
321 Symbol::CompareValueByAddr);
322 if (it != symbols_.begin()) {
323 --it;
324 if (it->addr <= vaddr_in_dso && (it->addr + it->len > vaddr_in_dso)) {
325 return &*it;
326 }
327 }
328 if (!unknown_symbols_.empty()) {
329 auto it = unknown_symbols_.find(vaddr_in_dso);
330 if (it != unknown_symbols_.end()) {
331 return &it->second;
332 }
333 }
334 return nullptr;
335 }
336
SetSymbols(std::vector<Symbol> * symbols)337 void Dso::SetSymbols(std::vector<Symbol>* symbols) {
338 symbols_ = std::move(*symbols);
339 symbols->clear();
340 }
341
AddUnknownSymbol(uint64_t vaddr_in_dso,const std::string & name)342 void Dso::AddUnknownSymbol(uint64_t vaddr_in_dso, const std::string& name) {
343 unknown_symbols_.insert(std::make_pair(vaddr_in_dso, Symbol(name, vaddr_in_dso, 1)));
344 }
345
IsForJavaMethod()346 bool Dso::IsForJavaMethod() {
347 if (type_ == DSO_DEX_FILE) {
348 return true;
349 }
350 if (type_ == DSO_ELF_FILE) {
351 // JIT symfiles for JITed Java methods are dumped as temporary files, whose name are in format
352 // "TemporaryFile-XXXXXX".
353 size_t pos = path_.rfind('/');
354 pos = (pos == std::string::npos) ? 0 : pos + 1;
355 return strncmp(&path_[pos], "TemporaryFile", strlen("TemporaryFile")) == 0;
356 }
357 return false;
358 }
359
Load()360 void Dso::Load() {
361 is_loaded_ = true;
362 std::vector<Symbol> symbols = LoadSymbols();
363 if (symbols_.empty()) {
364 symbols_ = std::move(symbols);
365 } else {
366 std::vector<Symbol> merged_symbols;
367 std::set_union(symbols_.begin(), symbols_.end(), symbols.begin(), symbols.end(),
368 std::back_inserter(merged_symbols), Symbol::CompareValueByAddr);
369 symbols_ = std::move(merged_symbols);
370 }
371 }
372
ReportReadElfSymbolResult(ElfStatus result,const std::string & path,const std::string & debug_file_path,android::base::LogSeverity warning_loglevel=android::base::WARNING)373 static void ReportReadElfSymbolResult(ElfStatus result, const std::string& path,
374 const std::string& debug_file_path,
375 android::base::LogSeverity warning_loglevel = android::base::WARNING) {
376 if (result == ElfStatus::NO_ERROR) {
377 LOG(VERBOSE) << "Read symbols from " << debug_file_path << " successfully";
378 } else if (result == ElfStatus::NO_SYMBOL_TABLE) {
379 if (path == "[vdso]") {
380 // Vdso only contains dynamic symbol table, and we can't change that.
381 return;
382 }
383 // Lacking symbol table isn't considered as an error but worth reporting.
384 LOG(warning_loglevel) << debug_file_path << " doesn't contain symbol table";
385 } else {
386 LOG(warning_loglevel) << "failed to read symbols from " << debug_file_path << ": " << result;
387 }
388 }
389
SortAndFixSymbols(std::vector<Symbol> & symbols)390 static void SortAndFixSymbols(std::vector<Symbol>& symbols) {
391 std::sort(symbols.begin(), symbols.end(), Symbol::CompareValueByAddr);
392 Symbol* prev_symbol = nullptr;
393 for (auto& symbol : symbols) {
394 if (prev_symbol != nullptr && prev_symbol->len == 0) {
395 prev_symbol->len = symbol.addr - prev_symbol->addr;
396 }
397 prev_symbol = &symbol;
398 }
399 }
400
401 class DexFileDso : public Dso {
402 public:
DexFileDso(const std::string & path,const std::string & debug_file_path)403 DexFileDso(const std::string& path, const std::string& debug_file_path)
404 : Dso(DSO_DEX_FILE, path, debug_file_path) {}
405
AddDexFileOffset(uint64_t dex_file_offset)406 void AddDexFileOffset(uint64_t dex_file_offset) override {
407 auto it = std::lower_bound(dex_file_offsets_.begin(), dex_file_offsets_.end(),
408 dex_file_offset);
409 if (it != dex_file_offsets_.end() && *it == dex_file_offset) {
410 return;
411 }
412 dex_file_offsets_.insert(it, dex_file_offset);
413 }
414
DexFileOffsets()415 const std::vector<uint64_t>* DexFileOffsets() override {
416 return &dex_file_offsets_;
417 }
418
IpToVaddrInFile(uint64_t ip,uint64_t map_start,uint64_t map_pgoff)419 uint64_t IpToVaddrInFile(uint64_t ip, uint64_t map_start, uint64_t map_pgoff) override {
420 return ip - map_start + map_pgoff;
421 }
422
LoadSymbols()423 std::vector<Symbol> LoadSymbols() override {
424 std::vector<Symbol> symbols;
425 std::vector<DexFileSymbol> dex_file_symbols;
426 auto tuple = SplitUrlInApk(debug_file_path_);
427 bool status = false;
428 if (std::get<0>(tuple)) {
429 std::unique_ptr<ArchiveHelper> ahelper = ArchiveHelper::CreateInstance(std::get<1>(tuple));
430 ZipEntry entry;
431 std::vector<uint8_t> data;
432 if (ahelper &&
433 ahelper->FindEntry(std::get<2>(tuple), &entry) && ahelper->GetEntryData(entry, &data)) {
434 status = ReadSymbolsFromDexFileInMemory(data.data(), data.size(), dex_file_offsets_,
435 &dex_file_symbols);
436 }
437 } else {
438 status = ReadSymbolsFromDexFile(debug_file_path_, dex_file_offsets_, &dex_file_symbols);
439 }
440 if (!status) {
441 android::base::LogSeverity level = symbols_.empty() ? android::base::WARNING
442 : android::base::DEBUG;
443 LOG(level) << "Failed to read symbols from " << debug_file_path_;
444 return symbols;
445 }
446 LOG(VERBOSE) << "Read symbols from " << debug_file_path_ << " successfully";
447 for (auto& symbol : dex_file_symbols) {
448 symbols.emplace_back(symbol.name, symbol.offset, symbol.len);
449 }
450 SortAndFixSymbols(symbols);
451 return symbols;
452 }
453
454 private:
455 std::vector<uint64_t> dex_file_offsets_;
456 };
457
458 class ElfDso : public Dso {
459 public:
ElfDso(const std::string & path,const std::string & debug_file_path)460 ElfDso(const std::string& path, const std::string& debug_file_path)
461 : Dso(DSO_ELF_FILE, path, debug_file_path) {}
462
SetMinExecutableVaddr(uint64_t min_vaddr,uint64_t file_offset)463 void SetMinExecutableVaddr(uint64_t min_vaddr, uint64_t file_offset) override {
464 min_vaddr_ = min_vaddr;
465 file_offset_of_min_vaddr_ = file_offset;
466 }
467
GetMinExecutableVaddr(uint64_t * min_vaddr,uint64_t * file_offset)468 void GetMinExecutableVaddr(uint64_t* min_vaddr, uint64_t* file_offset) override {
469 if (type_ == DSO_DEX_FILE) {
470 return dex_file_dso_->GetMinExecutableVaddr(min_vaddr, file_offset);
471 }
472 if (min_vaddr_ == uninitialized_value) {
473 min_vaddr_ = 0;
474 BuildId build_id = GetExpectedBuildId();
475 uint64_t addr;
476 uint64_t offset;
477 ElfStatus result;
478 auto tuple = SplitUrlInApk(debug_file_path_);
479 if (std::get<0>(tuple)) {
480 EmbeddedElf* elf = ApkInspector::FindElfInApkByName(std::get<1>(tuple),
481 std::get<2>(tuple));
482 if (elf == nullptr) {
483 result = ElfStatus::FILE_NOT_FOUND;
484 } else {
485 result = ReadMinExecutableVirtualAddressFromEmbeddedElfFile(
486 elf->filepath(), elf->entry_offset(), elf->entry_size(), build_id, &addr, &offset);
487 }
488 } else {
489 result = ReadMinExecutableVirtualAddressFromElfFile(debug_file_path_, build_id, &addr,
490 &offset);
491 }
492 if (result != ElfStatus::NO_ERROR) {
493 LOG(WARNING) << "failed to read min virtual address of "
494 << GetDebugFilePath() << ": " << result;
495 } else {
496 min_vaddr_ = addr;
497 file_offset_of_min_vaddr_ = offset;
498 }
499 }
500 *min_vaddr = min_vaddr_;
501 *file_offset = file_offset_of_min_vaddr_;
502 }
503
IpToVaddrInFile(uint64_t ip,uint64_t map_start,uint64_t map_pgoff)504 uint64_t IpToVaddrInFile(uint64_t ip, uint64_t map_start, uint64_t map_pgoff) override {
505 if (type_ == DSO_DEX_FILE) {
506 return dex_file_dso_->IpToVaddrInFile(ip, map_start, map_pgoff);
507 }
508 uint64_t min_vaddr;
509 uint64_t file_offset_of_min_vaddr;
510 GetMinExecutableVaddr(&min_vaddr, &file_offset_of_min_vaddr);
511 if (file_offset_of_min_vaddr == uninitialized_value) {
512 return ip - map_start + min_vaddr;
513 }
514 // Apps may make part of the executable segment of a shared library writeable, which can
515 // generate multiple executable segments at runtime. So use map_pgoff to calculate
516 // vaddr_in_file.
517 return ip - map_start + map_pgoff - file_offset_of_min_vaddr + min_vaddr;
518 }
519
AddDexFileOffset(uint64_t dex_file_offset)520 void AddDexFileOffset(uint64_t dex_file_offset) override {
521 if (type_ == DSO_ELF_FILE) {
522 // When simpleperf does unwinding while recording, it processes mmap records before reading
523 // dex file linked list (via JITDebugReader). To process mmap records, it creates Dso
524 // objects of type ELF_FILE. Then after reading dex file linked list, it realizes some
525 // ELF_FILE Dso objects should actually be DEX_FILE, because they have dex file offsets.
526 // So here converts ELF_FILE Dso into DEX_FILE Dso.
527 type_ = DSO_DEX_FILE;
528 dex_file_dso_.reset(new DexFileDso(path_, path_));
529 }
530 dex_file_dso_->AddDexFileOffset(dex_file_offset);
531 }
532
DexFileOffsets()533 const std::vector<uint64_t>* DexFileOffsets() override {
534 return dex_file_dso_ ? dex_file_dso_->DexFileOffsets() : nullptr;
535 }
536
537 protected:
LoadSymbols()538 std::vector<Symbol> LoadSymbols() override {
539 if (dex_file_dso_) {
540 return dex_file_dso_->LoadSymbols();
541 }
542 std::vector<Symbol> symbols;
543 BuildId build_id = GetExpectedBuildId();
544 auto symbol_callback = [&](const ElfFileSymbol& symbol) {
545 if (symbol.is_func || (symbol.is_label && symbol.is_in_text_section)) {
546 symbols.emplace_back(symbol.name, symbol.vaddr, symbol.len);
547 }
548 };
549 ElfStatus status;
550 std::tuple<bool, std::string, std::string> tuple = SplitUrlInApk(debug_file_path_);
551 if (std::get<0>(tuple)) {
552 EmbeddedElf* elf = ApkInspector::FindElfInApkByName(std::get<1>(tuple), std::get<2>(tuple));
553 if (elf == nullptr) {
554 status = ElfStatus::FILE_NOT_FOUND;
555 } else {
556 status = ParseSymbolsFromEmbeddedElfFile(elf->filepath(), elf->entry_offset(),
557 elf->entry_size(), build_id, symbol_callback);
558 }
559 } else {
560 status = ParseSymbolsFromElfFile(debug_file_path_, build_id, symbol_callback);
561 }
562 ReportReadElfSymbolResult(status, path_, debug_file_path_,
563 symbols_.empty() ? android::base::WARNING : android::base::DEBUG);
564 SortAndFixSymbols(symbols);
565 return symbols;
566 }
567
568 private:
569 static constexpr uint64_t uninitialized_value = std::numeric_limits<uint64_t>::max();
570
571 uint64_t min_vaddr_ = uninitialized_value;
572 uint64_t file_offset_of_min_vaddr_ = uninitialized_value;
573 std::unique_ptr<DexFileDso> dex_file_dso_;
574 };
575
576 class KernelDso : public Dso {
577 public:
KernelDso(const std::string & path,const std::string & debug_file_path)578 KernelDso(const std::string& path, const std::string& debug_file_path)
579 : Dso(DSO_KERNEL, path, debug_file_path) {}
580
IpToVaddrInFile(uint64_t ip,uint64_t,uint64_t)581 uint64_t IpToVaddrInFile(uint64_t ip, uint64_t, uint64_t) override {
582 return ip;
583 }
584
585 protected:
LoadSymbols()586 std::vector<Symbol> LoadSymbols() override {
587 std::vector<Symbol> symbols;
588 BuildId build_id = GetExpectedBuildId();
589 if (!vmlinux_.empty()) {
590 auto symbol_callback = [&](const ElfFileSymbol& symbol) {
591 if (symbol.is_func) {
592 symbols.emplace_back(symbol.name, symbol.vaddr, symbol.len);
593 }
594 };
595 ElfStatus status = ParseSymbolsFromElfFile(vmlinux_, build_id, symbol_callback);
596 ReportReadElfSymbolResult(status, path_, vmlinux_);
597 } else if (!kallsyms_.empty()) {
598 symbols = ReadSymbolsFromKallsyms(kallsyms_);
599 } else if (read_kernel_symbols_from_proc_ || !build_id.IsEmpty()) {
600 // Try /proc/kallsyms only when asked to do so, or when build id matches.
601 // Otherwise, it is likely to use /proc/kallsyms on host for perf.data recorded on device.
602 bool can_read_kallsyms = true;
603 if (!build_id.IsEmpty()) {
604 BuildId real_build_id;
605 if (!GetKernelBuildId(&real_build_id) || build_id != real_build_id) {
606 LOG(DEBUG) << "failed to read symbols from /proc/kallsyms: Build id mismatch";
607 can_read_kallsyms = false;
608 }
609 }
610 if (can_read_kallsyms) {
611 std::string kallsyms;
612 if (!android::base::ReadFileToString("/proc/kallsyms", &kallsyms)) {
613 LOG(DEBUG) << "failed to read /proc/kallsyms";
614 } else {
615 symbols = ReadSymbolsFromKallsyms(kallsyms);
616 }
617 }
618 }
619 SortAndFixSymbols(symbols);
620 if (!symbols.empty()) {
621 symbols.back().len = std::numeric_limits<uint64_t>::max() - symbols.back().addr;
622 }
623 return symbols;
624 }
625
626 private:
ReadSymbolsFromKallsyms(std::string & kallsyms)627 std::vector<Symbol> ReadSymbolsFromKallsyms(std::string& kallsyms) {
628 std::vector<Symbol> symbols;
629 auto symbol_callback = [&](const KernelSymbol& symbol) {
630 if (strchr("TtWw", symbol.type) && symbol.addr != 0u) {
631 symbols.emplace_back(symbol.name, symbol.addr, 0);
632 }
633 return false;
634 };
635 ProcessKernelSymbols(kallsyms, symbol_callback);
636 if (symbols.empty()) {
637 LOG(WARNING) << "Symbol addresses in /proc/kallsyms on device are all zero. "
638 "`echo 0 >/proc/sys/kernel/kptr_restrict` if possible.";
639 }
640 return symbols;
641 }
642 };
643
644 class KernelModuleDso : public Dso {
645 public:
KernelModuleDso(const std::string & path,const std::string & debug_file_path)646 KernelModuleDso(const std::string& path, const std::string& debug_file_path)
647 : Dso(DSO_KERNEL_MODULE, path, debug_file_path) {}
648
IpToVaddrInFile(uint64_t ip,uint64_t map_start,uint64_t)649 uint64_t IpToVaddrInFile(uint64_t ip, uint64_t map_start, uint64_t) override {
650 return ip - map_start;
651 }
652
653 protected:
LoadSymbols()654 std::vector<Symbol> LoadSymbols() override {
655 std::vector<Symbol> symbols;
656 BuildId build_id = GetExpectedBuildId();
657 auto symbol_callback = [&](const ElfFileSymbol& symbol) {
658 if (symbol.is_func || symbol.is_in_text_section) {
659 symbols.emplace_back(symbol.name, symbol.vaddr, symbol.len);
660 }
661 };
662 ElfStatus status = ParseSymbolsFromElfFile(debug_file_path_, build_id, symbol_callback);
663 ReportReadElfSymbolResult(status, path_, debug_file_path_,
664 symbols_.empty() ? android::base::WARNING : android::base::DEBUG);
665 SortAndFixSymbols(symbols);
666 return symbols;
667 }
668 };
669
670 class UnknownDso : public Dso {
671 public:
UnknownDso(const std::string & path)672 UnknownDso(const std::string& path) : Dso(DSO_UNKNOWN_FILE, path, path) {}
673
IpToVaddrInFile(uint64_t ip,uint64_t,uint64_t)674 uint64_t IpToVaddrInFile(uint64_t ip, uint64_t, uint64_t) override {
675 return ip;
676 }
677
678 protected:
LoadSymbols()679 std::vector<Symbol> LoadSymbols() override {
680 return std::vector<Symbol>();
681 }
682 };
683
CreateDso(DsoType dso_type,const std::string & dso_path,bool force_64bit)684 std::unique_ptr<Dso> Dso::CreateDso(DsoType dso_type, const std::string& dso_path,
685 bool force_64bit) {
686 switch (dso_type) {
687 case DSO_ELF_FILE: {
688 BuildId build_id = FindExpectedBuildIdForPath(dso_path);
689 return std::unique_ptr<Dso>(new ElfDso(dso_path,
690 debug_elf_file_finder_.FindDebugFile(dso_path, force_64bit, build_id)));
691 }
692 case DSO_KERNEL:
693 return std::unique_ptr<Dso>(new KernelDso(dso_path, dso_path));
694 case DSO_KERNEL_MODULE:
695 return std::unique_ptr<Dso>(new KernelModuleDso(dso_path, dso_path));
696 case DSO_DEX_FILE:
697 return std::unique_ptr<Dso>(new DexFileDso(dso_path, dso_path));
698 case DSO_UNKNOWN_FILE:
699 return std::unique_ptr<Dso>(new UnknownDso(dso_path));
700 default:
701 LOG(FATAL) << "Unexpected dso_type " << static_cast<int>(dso_type);
702 }
703 return nullptr;
704 }
705
DsoTypeToString(DsoType dso_type)706 const char* DsoTypeToString(DsoType dso_type) {
707 switch (dso_type) {
708 case DSO_KERNEL:
709 return "dso_kernel";
710 case DSO_KERNEL_MODULE:
711 return "dso_kernel_module";
712 case DSO_ELF_FILE:
713 return "dso_elf_file";
714 case DSO_DEX_FILE:
715 return "dso_dex_file";
716 default:
717 return "unknown";
718 }
719 }
720
GetBuildIdFromDsoPath(const std::string & dso_path,BuildId * build_id)721 bool GetBuildIdFromDsoPath(const std::string& dso_path, BuildId* build_id) {
722 auto tuple = SplitUrlInApk(dso_path);
723 ElfStatus result;
724 if (std::get<0>(tuple)) {
725 EmbeddedElf* elf = ApkInspector::FindElfInApkByName(std::get<1>(tuple), std::get<2>(tuple));
726 if (elf == nullptr) {
727 result = ElfStatus::FILE_NOT_FOUND;
728 } else {
729 result = GetBuildIdFromEmbeddedElfFile(elf->filepath(), elf->entry_offset(),
730 elf->entry_size(), build_id);
731 }
732 } else {
733 result = GetBuildIdFromElfFile(dso_path, build_id);
734 }
735 return result == ElfStatus::NO_ERROR;
736 }
737