1 //===-- OperatingSystemPython.cpp -----------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "lldb/Host/Config.h" 10 11 #if LLDB_ENABLE_PYTHON 12 13 #include "OperatingSystemPython.h" 14 15 #include "Plugins/Process/Utility/RegisterContextDummy.h" 16 #include "Plugins/Process/Utility/RegisterContextMemory.h" 17 #include "Plugins/Process/Utility/ThreadMemory.h" 18 #include "lldb/Core/Debugger.h" 19 #include "lldb/Core/Module.h" 20 #include "lldb/Core/PluginManager.h" 21 #include "lldb/Core/ValueObjectVariable.h" 22 #include "lldb/Interpreter/CommandInterpreter.h" 23 #include "lldb/Interpreter/ScriptInterpreter.h" 24 #include "lldb/Symbol/ObjectFile.h" 25 #include "lldb/Symbol/VariableList.h" 26 #include "lldb/Target/Process.h" 27 #include "lldb/Target/StopInfo.h" 28 #include "lldb/Target/Target.h" 29 #include "lldb/Target/Thread.h" 30 #include "lldb/Target/ThreadList.h" 31 #include "lldb/Utility/DataBufferHeap.h" 32 #include "lldb/Utility/LLDBLog.h" 33 #include "lldb/Utility/RegisterValue.h" 34 #include "lldb/Utility/StreamString.h" 35 #include "lldb/Utility/StructuredData.h" 36 37 #include <memory> 38 39 using namespace lldb; 40 using namespace lldb_private; 41 42 LLDB_PLUGIN_DEFINE(OperatingSystemPython) 43 44 void OperatingSystemPython::Initialize() { 45 PluginManager::RegisterPlugin(GetPluginNameStatic(), 46 GetPluginDescriptionStatic(), CreateInstance, 47 nullptr); 48 } 49 50 void OperatingSystemPython::Terminate() { 51 PluginManager::UnregisterPlugin(CreateInstance); 52 } 53 54 OperatingSystem *OperatingSystemPython::CreateInstance(Process *process, 55 bool force) { 56 // Python OperatingSystem plug-ins must be requested by name, so force must 57 // be true 58 FileSpec python_os_plugin_spec(process->GetPythonOSPluginPath()); 59 if (python_os_plugin_spec && 60 FileSystem::Instance().Exists(python_os_plugin_spec)) { 61 std::unique_ptr<OperatingSystemPython> os_up( 62 new OperatingSystemPython(process, python_os_plugin_spec)); 63 if (os_up.get() && os_up->IsValid()) 64 return os_up.release(); 65 } 66 return nullptr; 67 } 68 69 llvm::StringRef OperatingSystemPython::GetPluginDescriptionStatic() { 70 return "Operating system plug-in that gathers OS information from a python " 71 "class that implements the necessary OperatingSystem functionality."; 72 } 73 74 OperatingSystemPython::OperatingSystemPython(lldb_private::Process *process, 75 const FileSpec &python_module_path) 76 : OperatingSystem(process), m_thread_list_valobj_sp(), m_register_info_up(), 77 m_interpreter(nullptr), m_python_object_sp() { 78 if (!process) 79 return; 80 TargetSP target_sp = process->CalculateTarget(); 81 if (!target_sp) 82 return; 83 m_interpreter = target_sp->GetDebugger().GetScriptInterpreter(); 84 if (m_interpreter) { 85 86 std::string os_plugin_class_name( 87 python_module_path.GetFilename().AsCString("")); 88 if (!os_plugin_class_name.empty()) { 89 LoadScriptOptions options; 90 char python_module_path_cstr[PATH_MAX]; 91 python_module_path.GetPath(python_module_path_cstr, 92 sizeof(python_module_path_cstr)); 93 Status error; 94 if (m_interpreter->LoadScriptingModule(python_module_path_cstr, options, 95 error)) { 96 // Strip the ".py" extension if there is one 97 size_t py_extension_pos = os_plugin_class_name.rfind(".py"); 98 if (py_extension_pos != std::string::npos) 99 os_plugin_class_name.erase(py_extension_pos); 100 // Add ".OperatingSystemPlugIn" to the module name to get a string like 101 // "modulename.OperatingSystemPlugIn" 102 os_plugin_class_name += ".OperatingSystemPlugIn"; 103 StructuredData::ObjectSP object_sp = 104 m_interpreter->OSPlugin_CreatePluginObject( 105 os_plugin_class_name.c_str(), process->CalculateProcess()); 106 if (object_sp && object_sp->IsValid()) 107 m_python_object_sp = object_sp; 108 } 109 } 110 } 111 } 112 113 OperatingSystemPython::~OperatingSystemPython() = default; 114 115 DynamicRegisterInfo *OperatingSystemPython::GetDynamicRegisterInfo() { 116 if (m_register_info_up == nullptr) { 117 if (!m_interpreter || !m_python_object_sp) 118 return nullptr; 119 Log *log = GetLog(LLDBLog::OS); 120 121 LLDB_LOGF(log, 122 "OperatingSystemPython::GetDynamicRegisterInfo() fetching " 123 "thread register definitions from python for pid %" PRIu64, 124 m_process->GetID()); 125 126 StructuredData::DictionarySP dictionary = 127 m_interpreter->OSPlugin_RegisterInfo(m_python_object_sp); 128 if (!dictionary) 129 return nullptr; 130 131 m_register_info_up = std::make_unique<DynamicRegisterInfo>( 132 *dictionary, m_process->GetTarget().GetArchitecture()); 133 assert(m_register_info_up->GetNumRegisters() > 0); 134 assert(m_register_info_up->GetNumRegisterSets() > 0); 135 } 136 return m_register_info_up.get(); 137 } 138 139 bool OperatingSystemPython::UpdateThreadList(ThreadList &old_thread_list, 140 ThreadList &core_thread_list, 141 ThreadList &new_thread_list) { 142 if (!m_interpreter || !m_python_object_sp) 143 return false; 144 145 Log *log = GetLog(LLDBLog::OS); 146 147 // First thing we have to do is to try to get the API lock, and the 148 // interpreter lock. We're going to change the thread content of the process, 149 // and we're going to use python, which requires the API lock to do it. We 150 // need the interpreter lock to make sure thread_info_dict stays alive. 151 // 152 // If someone already has the API lock, that is ok, we just want to avoid 153 // external code from making new API calls while this call is happening. 154 // 155 // This is a recursive lock so we can grant it to any Python code called on 156 // the stack below us. 157 Target &target = m_process->GetTarget(); 158 std::unique_lock<std::recursive_mutex> api_lock(target.GetAPIMutex(), 159 std::defer_lock); 160 (void)api_lock.try_lock(); // See above. 161 auto interpreter_lock = m_interpreter->AcquireInterpreterLock(); 162 163 LLDB_LOGF(log, 164 "OperatingSystemPython::UpdateThreadList() fetching thread " 165 "data from python for pid %" PRIu64, 166 m_process->GetID()); 167 168 // The threads that are in "core_thread_list" upon entry are the threads from 169 // the lldb_private::Process subclass, no memory threads will be in this 170 // list. 171 StructuredData::ArraySP threads_list = 172 m_interpreter->OSPlugin_ThreadsInfo(m_python_object_sp); 173 174 const uint32_t num_cores = core_thread_list.GetSize(false); 175 176 // Make a map so we can keep track of which cores were used from the 177 // core_thread list. Any real threads/cores that weren't used should later be 178 // put back into the "new_thread_list". 179 std::vector<bool> core_used_map(num_cores, false); 180 if (threads_list) { 181 if (log) { 182 StreamString strm; 183 threads_list->Dump(strm); 184 LLDB_LOGF(log, "threads_list = %s", strm.GetData()); 185 } 186 187 const uint32_t num_threads = threads_list->GetSize(); 188 for (uint32_t i = 0; i < num_threads; ++i) { 189 StructuredData::ObjectSP thread_dict_obj = 190 threads_list->GetItemAtIndex(i); 191 if (auto thread_dict = thread_dict_obj->GetAsDictionary()) { 192 ThreadSP thread_sp(CreateThreadFromThreadInfo( 193 *thread_dict, core_thread_list, old_thread_list, core_used_map, 194 nullptr)); 195 if (thread_sp) 196 new_thread_list.AddThread(thread_sp); 197 } 198 } 199 } 200 201 // Any real core threads that didn't end up backing a memory thread should 202 // still be in the main thread list, and they should be inserted at the 203 // beginning of the list 204 uint32_t insert_idx = 0; 205 for (uint32_t core_idx = 0; core_idx < num_cores; ++core_idx) { 206 if (!core_used_map[core_idx]) { 207 new_thread_list.InsertThread( 208 core_thread_list.GetThreadAtIndex(core_idx, false), insert_idx); 209 ++insert_idx; 210 } 211 } 212 213 return new_thread_list.GetSize(false) > 0; 214 } 215 216 ThreadSP OperatingSystemPython::CreateThreadFromThreadInfo( 217 StructuredData::Dictionary &thread_dict, ThreadList &core_thread_list, 218 ThreadList &old_thread_list, std::vector<bool> &core_used_map, 219 bool *did_create_ptr) { 220 ThreadSP thread_sp; 221 tid_t tid = LLDB_INVALID_THREAD_ID; 222 if (!thread_dict.GetValueForKeyAsInteger("tid", tid)) 223 return ThreadSP(); 224 225 uint32_t core_number; 226 addr_t reg_data_addr; 227 llvm::StringRef name; 228 llvm::StringRef queue; 229 230 thread_dict.GetValueForKeyAsInteger("core", core_number, UINT32_MAX); 231 thread_dict.GetValueForKeyAsInteger("register_data_addr", reg_data_addr, 232 LLDB_INVALID_ADDRESS); 233 thread_dict.GetValueForKeyAsString("name", name); 234 thread_dict.GetValueForKeyAsString("queue", queue); 235 236 // See if a thread already exists for "tid" 237 thread_sp = old_thread_list.FindThreadByID(tid, false); 238 if (thread_sp) { 239 // A thread already does exist for "tid", make sure it was an operating 240 // system 241 // plug-in generated thread. 242 if (!IsOperatingSystemPluginThread(thread_sp)) { 243 // We have thread ID overlap between the protocol threads and the 244 // operating system threads, clear the thread so we create an operating 245 // system thread for this. 246 thread_sp.reset(); 247 } 248 } 249 250 if (!thread_sp) { 251 if (did_create_ptr) 252 *did_create_ptr = true; 253 thread_sp = std::make_shared<ThreadMemory>(*m_process, tid, name, queue, 254 reg_data_addr); 255 } 256 257 if (core_number < core_thread_list.GetSize(false)) { 258 ThreadSP core_thread_sp( 259 core_thread_list.GetThreadAtIndex(core_number, false)); 260 if (core_thread_sp) { 261 // Keep track of which cores were set as the backing thread for memory 262 // threads... 263 if (core_number < core_used_map.size()) 264 core_used_map[core_number] = true; 265 266 ThreadSP backing_core_thread_sp(core_thread_sp->GetBackingThread()); 267 if (backing_core_thread_sp) { 268 thread_sp->SetBackingThread(backing_core_thread_sp); 269 } else { 270 thread_sp->SetBackingThread(core_thread_sp); 271 } 272 } 273 } 274 return thread_sp; 275 } 276 277 void OperatingSystemPython::ThreadWasSelected(Thread *thread) {} 278 279 RegisterContextSP 280 OperatingSystemPython::CreateRegisterContextForThread(Thread *thread, 281 addr_t reg_data_addr) { 282 RegisterContextSP reg_ctx_sp; 283 if (!m_interpreter || !m_python_object_sp || !thread) 284 return reg_ctx_sp; 285 286 if (!IsOperatingSystemPluginThread(thread->shared_from_this())) 287 return reg_ctx_sp; 288 289 // First thing we have to do is to try to get the API lock, and the 290 // interpreter lock. We're going to change the thread content of the process, 291 // and we're going to use python, which requires the API lock to do it. We 292 // need the interpreter lock to make sure thread_info_dict stays alive. 293 // 294 // If someone already has the API lock, that is ok, we just want to avoid 295 // external code from making new API calls while this call is happening. 296 // 297 // This is a recursive lock so we can grant it to any Python code called on 298 // the stack below us. 299 Target &target = m_process->GetTarget(); 300 std::unique_lock<std::recursive_mutex> api_lock(target.GetAPIMutex(), 301 std::defer_lock); 302 (void)api_lock.try_lock(); // See above. 303 auto interpreter_lock = m_interpreter->AcquireInterpreterLock(); 304 305 Log *log = GetLog(LLDBLog::Thread); 306 307 if (reg_data_addr != LLDB_INVALID_ADDRESS) { 308 // The registers data is in contiguous memory, just create the register 309 // context using the address provided 310 LLDB_LOGF(log, 311 "OperatingSystemPython::CreateRegisterContextForThread (tid " 312 "= 0x%" PRIx64 ", 0x%" PRIx64 ", reg_data_addr = 0x%" PRIx64 313 ") creating memory register context", 314 thread->GetID(), thread->GetProtocolID(), reg_data_addr); 315 reg_ctx_sp = std::make_shared<RegisterContextMemory>( 316 *thread, 0, *GetDynamicRegisterInfo(), reg_data_addr); 317 } else { 318 // No register data address is provided, query the python plug-in to let it 319 // make up the data as it sees fit 320 LLDB_LOGF(log, 321 "OperatingSystemPython::CreateRegisterContextForThread (tid " 322 "= 0x%" PRIx64 ", 0x%" PRIx64 323 ") fetching register data from python", 324 thread->GetID(), thread->GetProtocolID()); 325 326 StructuredData::StringSP reg_context_data = 327 m_interpreter->OSPlugin_RegisterContextData(m_python_object_sp, 328 thread->GetID()); 329 if (reg_context_data) { 330 std::string value = std::string(reg_context_data->GetValue()); 331 DataBufferSP data_sp(new DataBufferHeap(value.c_str(), value.length())); 332 if (data_sp->GetByteSize()) { 333 RegisterContextMemory *reg_ctx_memory = new RegisterContextMemory( 334 *thread, 0, *GetDynamicRegisterInfo(), LLDB_INVALID_ADDRESS); 335 if (reg_ctx_memory) { 336 reg_ctx_sp.reset(reg_ctx_memory); 337 reg_ctx_memory->SetAllRegisterData(data_sp); 338 } 339 } 340 } 341 } 342 // if we still have no register data, fallback on a dummy context to avoid 343 // crashing 344 if (!reg_ctx_sp) { 345 LLDB_LOGF(log, 346 "OperatingSystemPython::CreateRegisterContextForThread (tid " 347 "= 0x%" PRIx64 ") forcing a dummy register context", 348 thread->GetID()); 349 reg_ctx_sp = std::make_shared<RegisterContextDummy>( 350 *thread, 0, target.GetArchitecture().GetAddressByteSize()); 351 } 352 return reg_ctx_sp; 353 } 354 355 StopInfoSP 356 OperatingSystemPython::CreateThreadStopReason(lldb_private::Thread *thread) { 357 // We should have gotten the thread stop info from the dictionary of data for 358 // the thread in the initial call to get_thread_info(), this should have been 359 // cached so we can return it here 360 StopInfoSP 361 stop_info_sp; //(StopInfo::CreateStopReasonWithSignal (*thread, SIGSTOP)); 362 return stop_info_sp; 363 } 364 365 lldb::ThreadSP OperatingSystemPython::CreateThread(lldb::tid_t tid, 366 addr_t context) { 367 Log *log = GetLog(LLDBLog::Thread); 368 369 LLDB_LOGF(log, 370 "OperatingSystemPython::CreateThread (tid = 0x%" PRIx64 371 ", context = 0x%" PRIx64 ") fetching register data from python", 372 tid, context); 373 374 if (m_interpreter && m_python_object_sp) { 375 // First thing we have to do is to try to get the API lock, and the 376 // interpreter lock. We're going to change the thread content of the 377 // process, and we're going to use python, which requires the API lock to 378 // do it. We need the interpreter lock to make sure thread_info_dict stays 379 // alive. 380 // 381 // If someone already has the API lock, that is ok, we just want to avoid 382 // external code from making new API calls while this call is happening. 383 // 384 // This is a recursive lock so we can grant it to any Python code called on 385 // the stack below us. 386 Target &target = m_process->GetTarget(); 387 std::unique_lock<std::recursive_mutex> api_lock(target.GetAPIMutex(), 388 std::defer_lock); 389 (void)api_lock.try_lock(); // See above. 390 auto interpreter_lock = m_interpreter->AcquireInterpreterLock(); 391 392 StructuredData::DictionarySP thread_info_dict = 393 m_interpreter->OSPlugin_CreateThread(m_python_object_sp, tid, context); 394 std::vector<bool> core_used_map; 395 if (thread_info_dict) { 396 ThreadList core_threads(m_process); 397 ThreadList &thread_list = m_process->GetThreadList(); 398 bool did_create = false; 399 ThreadSP thread_sp( 400 CreateThreadFromThreadInfo(*thread_info_dict, core_threads, 401 thread_list, core_used_map, &did_create)); 402 if (did_create) 403 thread_list.AddThread(thread_sp); 404 return thread_sp; 405 } 406 } 407 return ThreadSP(); 408 } 409 410 #endif // #if LLDB_ENABLE_PYTHON 411