xref: /aosp_15_r20/system/extras/simpleperf/thread_tree.cpp (revision 288bf5226967eb3dac5cce6c939ccc2a7f2b4fe5)
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 "thread_tree.h"
18  
19  #include <inttypes.h>
20  
21  #include <limits>
22  
23  #include <android-base/logging.h>
24  #include <android-base/stringprintf.h>
25  #include <android-base/strings.h>
26  
27  #include "perf_event.h"
28  #include "record.h"
29  #include "record_file.h"
30  #include "utils.h"
31  
32  namespace simpleperf {
33  namespace {
34  
35  // Real map file path depends on where the process can create files.
36  // For example, app can create files only in its data directory.
37  // Use normalized name inherited from pid instead.
GetSymbolMapDsoName(int pid)38  std::string GetSymbolMapDsoName(int pid) {
39    return android::base::StringPrintf("perf-%d.map", pid);
40  }
41  
42  }  // namespace
43  
SetThreadName(int pid,int tid,const std::string & comm)44  void ThreadTree::SetThreadName(int pid, int tid, const std::string& comm) {
45    ThreadEntry* thread = FindThreadOrNew(pid, tid);
46    if (comm != thread->comm) {
47      thread_comm_storage_.push_back(std::unique_ptr<std::string>(new std::string(comm)));
48      thread->comm = thread_comm_storage_.back()->c_str();
49    }
50  }
51  
ForkThread(int pid,int tid,int ppid,int ptid)52  bool ThreadTree::ForkThread(int pid, int tid, int ppid, int ptid) {
53    // Check thread ID.
54    if (tid == ptid) {
55      return false;
56    }
57    // Check thread group ID (pid here) as in https://linux.die.net/man/2/clone2.
58    if (pid != tid && pid != ppid) {
59      return false;
60    }
61    ThreadEntry* parent = FindThreadOrNew(ppid, ptid);
62    ThreadEntry* child = FindThreadOrNew(pid, tid);
63    child->comm = parent->comm;
64    if (pid != ppid) {
65      // Copy maps from parent process.
66      if (child->maps->maps.empty()) {
67        *child->maps = *parent->maps;
68      } else {
69        CHECK_NE(child->maps, parent->maps);
70        for (auto& pair : parent->maps->maps) {
71          InsertMap(*child->maps, *pair.second);
72        }
73      }
74    }
75    return true;
76  }
77  
FindThread(int tid) const78  ThreadEntry* ThreadTree::FindThread(int tid) const {
79    if (auto it = thread_tree_.find(tid); it != thread_tree_.end()) {
80      return it->second.get();
81    }
82    return nullptr;
83  }
84  
FindThreadOrNew(int pid,int tid)85  ThreadEntry* ThreadTree::FindThreadOrNew(int pid, int tid) {
86    auto it = thread_tree_.find(tid);
87    if (it != thread_tree_.end() && pid == it->second.get()->pid) {
88      return it->second.get();
89    }
90    if (it != thread_tree_.end()) {
91      ExitThread(it->second.get()->pid, tid);
92    }
93    return CreateThread(pid, tid);
94  }
95  
CreateThread(int pid,int tid)96  ThreadEntry* ThreadTree::CreateThread(int pid, int tid) {
97    const char* comm;
98    std::shared_ptr<MapSet> maps;
99    if (pid == tid) {
100      comm = "unknown";
101      maps.reset(new MapSet);
102    } else {
103      // Share maps among threads in the same thread group.
104      ThreadEntry* process = FindThreadOrNew(pid, pid);
105      comm = process->comm;
106      maps = process->maps;
107    }
108    ThreadEntry* thread = new ThreadEntry{
109        pid,
110        tid,
111        comm,
112        maps,
113    };
114    auto pair = thread_tree_.insert(std::make_pair(tid, std::unique_ptr<ThreadEntry>(thread)));
115    CHECK(pair.second);
116    if (pid == tid) {
117      // If there is a symbol map dso for the process, add maps for the symbols.
118      auto name = GetSymbolMapDsoName(pid);
119      auto it = user_dso_tree_.find(name);
120      if (it != user_dso_tree_.end()) {
121        AddThreadMapsForDsoSymbols(thread, it->second.get());
122      }
123    }
124    return thread;
125  }
126  
ExitThread(int pid,int tid)127  void ThreadTree::ExitThread(int pid, int tid) {
128    auto it = thread_tree_.find(tid);
129    if (it != thread_tree_.end() && pid == it->second.get()->pid) {
130      thread_tree_.erase(it);
131    }
132  }
133  
AddKernelMap(uint64_t start_addr,uint64_t len,uint64_t pgoff,const std::string & filename)134  void ThreadTree::AddKernelMap(uint64_t start_addr, uint64_t len, uint64_t pgoff,
135                                const std::string& filename) {
136    // kernel map len can be 0 when record command is not run in supervisor mode.
137    if (len == 0) {
138      return;
139    }
140    Dso* dso;
141    if (android::base::StartsWith(filename, DEFAULT_KERNEL_MMAP_NAME) ||
142        android::base::StartsWith(filename, DEFAULT_KERNEL_BPF_MMAP_NAME)) {
143      dso = FindKernelDsoOrNew();
144    } else {
145      dso = FindKernelModuleDsoOrNew(filename, start_addr, start_addr + len);
146    }
147    InsertMap(kernel_maps_, MapEntry(start_addr, len, pgoff, dso, true));
148  }
149  
FindKernelDsoOrNew()150  Dso* ThreadTree::FindKernelDsoOrNew() {
151    if (!kernel_dso_) {
152      kernel_dso_ = Dso::CreateDso(DSO_KERNEL, DEFAULT_KERNEL_MMAP_NAME);
153    }
154    return kernel_dso_.get();
155  }
156  
FindKernelModuleDsoOrNew(const std::string & filename,uint64_t memory_start,uint64_t memory_end)157  Dso* ThreadTree::FindKernelModuleDsoOrNew(const std::string& filename, uint64_t memory_start,
158                                            uint64_t memory_end) {
159    auto it = module_dso_tree_.find(filename);
160    if (it == module_dso_tree_.end()) {
161      module_dso_tree_[filename] =
162          Dso::CreateKernelModuleDso(filename, memory_start, memory_end, FindKernelDsoOrNew());
163      it = module_dso_tree_.find(filename);
164    }
165    return it->second.get();
166  }
167  
AddThreadMap(int pid,int tid,uint64_t start_addr,uint64_t len,uint64_t pgoff,const std::string & filename,uint32_t flags)168  void ThreadTree::AddThreadMap(int pid, int tid, uint64_t start_addr, uint64_t len, uint64_t pgoff,
169                                const std::string& filename, uint32_t flags) {
170    ThreadEntry* thread = FindThreadOrNew(pid, tid);
171    Dso* dso = FindUserDsoOrNew(filename, start_addr);
172    CHECK(dso != nullptr);
173    InsertMap(*thread->maps, MapEntry(start_addr, len, pgoff, dso, false, flags));
174  }
175  
AddThreadMapsForDsoSymbols(ThreadEntry * thread,Dso * dso)176  void ThreadTree::AddThreadMapsForDsoSymbols(ThreadEntry* thread, Dso* dso) {
177    const uint64_t page_size = GetPageSize();
178  
179    auto maps = thread->maps;
180  
181    uint64_t map_start = 0;
182    uint64_t map_end = 0;
183  
184    // Dso symbols are sorted by address. Walk and calculate containing pages.
185    for (const auto& sym : dso->GetSymbols()) {
186      uint64_t sym_map_start = AlignDown(sym.addr, page_size);
187      uint64_t sym_map_end = Align(sym.addr + sym.len, page_size);
188  
189      if (map_end < sym_map_start) {
190        if (map_start < map_end) {
191          InsertMap(*maps, MapEntry(map_start, map_end - map_start, map_start, dso, false, 0));
192        }
193        map_start = sym_map_start;
194      }
195      if (map_end < sym_map_end) {
196        map_end = sym_map_end;
197      }
198    }
199  
200    if (map_start < map_end) {
201      InsertMap(*maps, MapEntry(map_start, map_end - map_start, map_start, dso, false, 0));
202    }
203  }
204  
FindUserDsoOrNew(const std::string & filename,uint64_t start_addr,DsoType dso_type)205  Dso* ThreadTree::FindUserDsoOrNew(const std::string& filename, uint64_t start_addr,
206                                    DsoType dso_type) {
207    auto it = user_dso_tree_.find(filename);
208    if (it == user_dso_tree_.end()) {
209      bool force_64bit = start_addr > UINT_MAX;
210      std::unique_ptr<Dso> dso = Dso::CreateDso(dso_type, filename, force_64bit);
211      if (!dso) {
212        return nullptr;
213      }
214      auto pair = user_dso_tree_.insert(std::make_pair(filename, std::move(dso)));
215      CHECK(pair.second);
216      it = pair.first;
217    }
218    return it->second.get();
219  }
220  
AddSymbolsForProcess(int pid,std::vector<Symbol> * symbols)221  void ThreadTree::AddSymbolsForProcess(int pid, std::vector<Symbol>* symbols) {
222    auto name = GetSymbolMapDsoName(pid);
223  
224    auto dso = FindUserDsoOrNew(name, 0, DSO_SYMBOL_MAP_FILE);
225    dso->SetSymbols(symbols);
226  
227    auto thread = FindThreadOrNew(pid, pid);
228    AddThreadMapsForDsoSymbols(thread, dso);
229  }
230  
AllocateMap(const MapEntry & entry)231  const MapEntry* ThreadTree::AllocateMap(const MapEntry& entry) {
232    map_storage_.emplace_back(new MapEntry(entry));
233    return map_storage_.back().get();
234  }
235  
RemoveFirstPartOfMapEntry(const MapEntry * entry,uint64_t new_start_addr)236  static MapEntry RemoveFirstPartOfMapEntry(const MapEntry* entry, uint64_t new_start_addr) {
237    MapEntry result = *entry;
238    result.start_addr = new_start_addr;
239    result.len -= result.start_addr - entry->start_addr;
240    result.pgoff += result.start_addr - entry->start_addr;
241    return result;
242  }
243  
RemoveSecondPartOfMapEntry(const MapEntry * entry,uint64_t new_len)244  static MapEntry RemoveSecondPartOfMapEntry(const MapEntry* entry, uint64_t new_len) {
245    MapEntry result = *entry;
246    result.len = new_len;
247    return result;
248  }
249  
250  // Insert a new map entry in a MapSet. If some existing map entries overlap the new map entry,
251  // then remove the overlapped parts.
InsertMap(MapSet & maps,const MapEntry & entry)252  void ThreadTree::InsertMap(MapSet& maps, const MapEntry& entry) {
253    std::map<uint64_t, const MapEntry*>& map = maps.maps;
254    auto it = map.lower_bound(entry.start_addr);
255    // Remove overlapped entry with start_addr < entry.start_addr.
256    if (it != map.begin()) {
257      auto it2 = it;
258      --it2;
259      if (it2->second->get_end_addr() > entry.get_end_addr()) {
260        map.emplace(entry.get_end_addr(),
261                    AllocateMap(RemoveFirstPartOfMapEntry(it2->second, entry.get_end_addr())));
262      }
263      if (it2->second->get_end_addr() > entry.start_addr) {
264        it2->second =
265            AllocateMap(RemoveSecondPartOfMapEntry(it2->second, entry.start_addr - it2->first));
266      }
267    }
268    // Remove overlapped entries with start_addr >= entry.start_addr.
269    while (it != map.end() && it->second->get_end_addr() <= entry.get_end_addr()) {
270      it = map.erase(it);
271    }
272    if (it != map.end() && it->second->start_addr < entry.get_end_addr()) {
273      map.emplace(entry.get_end_addr(),
274                  AllocateMap(RemoveFirstPartOfMapEntry(it->second, entry.get_end_addr())));
275      map.erase(it);
276    }
277    // Insert the new entry.
278    map.emplace(entry.start_addr, AllocateMap(entry));
279    maps.version++;
280  }
281  
FindMapByAddr(uint64_t addr) const282  const MapEntry* MapSet::FindMapByAddr(uint64_t addr) const {
283    auto it = maps.upper_bound(addr);
284    if (it != maps.begin()) {
285      --it;
286      if (it->second->get_end_addr() > addr) {
287        return it->second;
288      }
289    }
290    return nullptr;
291  }
292  
FindMap(const ThreadEntry * thread,uint64_t ip,bool in_kernel)293  const MapEntry* ThreadTree::FindMap(const ThreadEntry* thread, uint64_t ip, bool in_kernel) {
294    const MapEntry* result = nullptr;
295    if (!in_kernel) {
296      result = thread->maps->FindMapByAddr(ip);
297    } else {
298      result = kernel_maps_.FindMapByAddr(ip);
299    }
300    return result != nullptr ? result : &unknown_map_;
301  }
302  
FindMap(const ThreadEntry * thread,uint64_t ip)303  const MapEntry* ThreadTree::FindMap(const ThreadEntry* thread, uint64_t ip) {
304    const MapEntry* result = thread->maps->FindMapByAddr(ip);
305    if (result != nullptr) {
306      return result;
307    }
308    result = kernel_maps_.FindMapByAddr(ip);
309    return result != nullptr ? result : &unknown_map_;
310  }
311  
FindSymbol(const MapEntry * map,uint64_t ip,uint64_t * pvaddr_in_file,Dso ** pdso)312  const Symbol* ThreadTree::FindSymbol(const MapEntry* map, uint64_t ip, uint64_t* pvaddr_in_file,
313                                       Dso** pdso) {
314    uint64_t vaddr_in_file = 0;
315    const Symbol* symbol = nullptr;
316    Dso* dso = map->dso;
317    if (map->flags & map_flags::PROT_JIT_SYMFILE_MAP) {
318      vaddr_in_file = ip;
319    } else {
320      vaddr_in_file = dso->IpToVaddrInFile(ip, map->start_addr, map->pgoff);
321    }
322    symbol = dso->FindSymbol(vaddr_in_file);
323    if (symbol == nullptr && dso->type() == DSO_KERNEL_MODULE) {
324      // If the ip address hits the vmlinux, or hits a kernel module, but we can't find its symbol
325      // in the kernel module file, then find its symbol in /proc/kallsyms or vmlinux.
326      vaddr_in_file = ip;
327      dso = FindKernelDsoOrNew();
328      symbol = dso->FindSymbol(vaddr_in_file);
329    }
330  
331    if (symbol == nullptr) {
332      if (show_ip_for_unknown_symbol_) {
333        std::string name = android::base::StringPrintf("%s%s[+%" PRIx64 "]",
334                                                       (show_mark_for_unknown_symbol_ ? "*" : ""),
335                                                       dso->FileName().c_str(), vaddr_in_file);
336        dso->AddUnknownSymbol(vaddr_in_file, name);
337        symbol = dso->FindSymbol(vaddr_in_file);
338        CHECK(symbol != nullptr);
339      } else {
340        symbol = &unknown_symbol_;
341      }
342    }
343    if (pvaddr_in_file != nullptr) {
344      *pvaddr_in_file = vaddr_in_file;
345    }
346    if (pdso != nullptr) {
347      *pdso = dso;
348    }
349    return symbol;
350  }
351  
FindKernelSymbol(uint64_t ip)352  const Symbol* ThreadTree::FindKernelSymbol(uint64_t ip) {
353    const MapEntry* map = FindMap(nullptr, ip, true);
354    return FindSymbol(map, ip, nullptr);
355  }
356  
ClearThreadAndMap()357  void ThreadTree::ClearThreadAndMap() {
358    thread_tree_.clear();
359    thread_comm_storage_.clear();
360    kernel_maps_.maps.clear();
361    map_storage_.clear();
362  }
363  
AddDsoInfo(FileFeature & file)364  bool ThreadTree::AddDsoInfo(FileFeature& file) {
365    DsoType dso_type = file.type;
366    Dso* dso = nullptr;
367    if (dso_type == DSO_KERNEL) {
368      dso = FindKernelDsoOrNew();
369    } else if (dso_type == DSO_KERNEL_MODULE) {
370      dso = FindKernelModuleDsoOrNew(file.path, 0, 0);
371    } else {
372      dso = FindUserDsoOrNew(file.path, 0, dso_type);
373    }
374    if (!dso) {
375      return false;
376    }
377    dso->SetMinExecutableVaddr(file.min_vaddr, file.file_offset_of_min_vaddr);
378    dso->SetSymbols(&file.symbols);
379    for (uint64_t offset : file.dex_file_offsets) {
380      dso->AddDexFileOffset(offset);
381    }
382    return true;
383  }
384  
AddDexFileOffset(const std::string & file_path,uint64_t dex_file_offset)385  void ThreadTree::AddDexFileOffset(const std::string& file_path, uint64_t dex_file_offset) {
386    Dso* dso = FindUserDsoOrNew(file_path, 0, DSO_DEX_FILE);
387    dso->AddDexFileOffset(dex_file_offset);
388  }
389  
Update(const Record & record)390  void ThreadTree::Update(const Record& record) {
391    if (record.type() == PERF_RECORD_MMAP) {
392      const MmapRecord& r = *static_cast<const MmapRecord*>(&record);
393      if (r.InKernel()) {
394        AddKernelMap(r.data->addr, r.data->len, r.data->pgoff, r.filename);
395      } else {
396        AddThreadMap(r.data->pid, r.data->tid, r.data->addr, r.data->len, r.data->pgoff, r.filename);
397      }
398    } else if (record.type() == PERF_RECORD_MMAP2) {
399      const Mmap2Record& r = *static_cast<const Mmap2Record*>(&record);
400      if (r.InKernel()) {
401        AddKernelMap(r.data->addr, r.data->len, r.data->pgoff, r.filename);
402      } else {
403        std::string filename =
404            (r.filename == DEFAULT_EXECNAME_FOR_THREAD_MMAP) ? "[unknown]" : r.filename;
405        AddThreadMap(r.data->pid, r.data->tid, r.data->addr, r.data->len, r.data->pgoff, filename,
406                     r.data->prot);
407      }
408    } else if (record.type() == PERF_RECORD_COMM) {
409      const CommRecord& r = *static_cast<const CommRecord*>(&record);
410      SetThreadName(r.data->pid, r.data->tid, r.comm);
411    } else if (record.type() == PERF_RECORD_FORK) {
412      const ForkRecord& r = *static_cast<const ForkRecord*>(&record);
413      ForkThread(r.data->pid, r.data->tid, r.data->ppid, r.data->ptid);
414    } else if (record.type() == PERF_RECORD_EXIT) {
415      if (!disable_thread_exit_records_) {
416        const ExitRecord& r = *static_cast<const ExitRecord*>(&record);
417        ExitThread(r.data->pid, r.data->tid);
418      }
419    } else if (record.type() == SIMPLE_PERF_RECORD_KERNEL_SYMBOL) {
420      const auto& r = *static_cast<const KernelSymbolRecord*>(&record);
421      Dso::SetKallsyms(std::string(r.kallsyms, r.kallsyms_size));
422    }
423  }
424  
GetAllDsos() const425  std::vector<Dso*> ThreadTree::GetAllDsos() const {
426    std::vector<Dso*> result;
427    if (kernel_dso_) {
428      result.push_back(kernel_dso_.get());
429    }
430    for (auto& p : module_dso_tree_) {
431      result.push_back(p.second.get());
432    }
433    for (auto& p : user_dso_tree_) {
434      result.push_back(p.second.get());
435    }
436    result.push_back(unknown_dso_.get());
437    return result;
438  }
439  
440  }  // namespace simpleperf
441