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