1 //===-- AppleGetThreadItemInfoHandler.cpp -------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "AppleGetThreadItemInfoHandler.h" 11 12 // C Includes 13 // C++ Includes 14 // Other libraries and framework includes 15 // Project includes 16 17 #include "lldb/Core/ConstString.h" 18 #include "lldb/Core/Log.h" 19 #include "lldb/Core/Module.h" 20 #include "lldb/Core/StreamString.h" 21 #include "lldb/Core/Value.h" 22 #include "lldb/Expression/DiagnosticManager.h" 23 #include "lldb/Expression/Expression.h" 24 #include "lldb/Expression/FunctionCaller.h" 25 #include "lldb/Expression/UtilityFunction.h" 26 #include "lldb/Symbol/ClangASTContext.h" 27 #include "lldb/Symbol/Symbol.h" 28 #include "lldb/Target/ExecutionContext.h" 29 #include "lldb/Target/Process.h" 30 #include "lldb/Target/StackFrame.h" 31 #include "lldb/Target/Target.h" 32 #include "lldb/Target/Thread.h" 33 #include "lldb/lldb-private.h" 34 35 using namespace lldb; 36 using namespace lldb_private; 37 38 const char *AppleGetThreadItemInfoHandler::g_get_thread_item_info_function_name = "__lldb_backtrace_recording_get_thread_item_info"; 39 const char *AppleGetThreadItemInfoHandler::g_get_thread_item_info_function_code = " \n\ 40 extern \"C\" \n\ 41 { \n\ 42 /* \n\ 43 * mach defines \n\ 44 */ \n\ 45 \n\ 46 typedef unsigned int uint32_t; \n\ 47 typedef unsigned long long uint64_t; \n\ 48 typedef uint32_t mach_port_t; \n\ 49 typedef mach_port_t vm_map_t; \n\ 50 typedef int kern_return_t; \n\ 51 typedef uint64_t mach_vm_address_t; \n\ 52 typedef uint64_t mach_vm_size_t; \n\ 53 \n\ 54 mach_port_t mach_task_self (); \n\ 55 kern_return_t mach_vm_deallocate (vm_map_t target, mach_vm_address_t address, mach_vm_size_t size); \n\ 56 \n\ 57 typedef void *pthread_t; \n\ 58 extern int printf(const char *format, ...); \n\ 59 extern pthread_t pthread_self(void); \n\ 60 \n\ 61 /* \n\ 62 * libBacktraceRecording defines \n\ 63 */ \n\ 64 \n\ 65 typedef uint32_t queue_list_scope_t; \n\ 66 typedef void *dispatch_queue_t; \n\ 67 typedef void *introspection_dispatch_queue_info_t; \n\ 68 typedef void *introspection_dispatch_item_info_ref; \n\ 69 \n\ 70 extern void __introspection_dispatch_thread_get_item_info (uint64_t thread_id, \n\ 71 introspection_dispatch_item_info_ref *returned_queues_buffer, \n\ 72 uint64_t *returned_queues_buffer_size); \n\ 73 \n\ 74 /* \n\ 75 * return type define \n\ 76 */ \n\ 77 \n\ 78 struct get_thread_item_info_return_values \n\ 79 { \n\ 80 uint64_t item_info_buffer_ptr; /* the address of the items buffer from libBacktraceRecording */ \n\ 81 uint64_t item_info_buffer_size; /* the size of the items buffer from libBacktraceRecording */ \n\ 82 }; \n\ 83 \n\ 84 void __lldb_backtrace_recording_get_thread_item_info \n\ 85 (struct get_thread_item_info_return_values *return_buffer, \n\ 86 int debug, \n\ 87 uint64_t thread_id, \n\ 88 void *page_to_free, \n\ 89 uint64_t page_to_free_size) \n\ 90 { \n\ 91 void *pthread_id = pthread_self (); \n\ 92 if (debug) \n\ 93 printf (\"entering get_thread_item_info with args return_buffer == %p, debug == %d, thread id == 0x%llx, page_to_free == %p, page_to_free_size == 0x%llx\\n\", return_buffer, debug, (uint64_t) thread_id, page_to_free, page_to_free_size); \n\ 94 if (page_to_free != 0) \n\ 95 { \n\ 96 mach_vm_deallocate (mach_task_self(), (mach_vm_address_t) page_to_free, (mach_vm_size_t) page_to_free_size); \n\ 97 } \n\ 98 \n\ 99 __introspection_dispatch_thread_get_item_info (thread_id, \n\ 100 (void**)&return_buffer->item_info_buffer_ptr, \n\ 101 &return_buffer->item_info_buffer_size); \n\ 102 } \n\ 103 } \n\ 104 "; 105 106 AppleGetThreadItemInfoHandler::AppleGetThreadItemInfoHandler(Process *process) 107 : m_process(process), 108 m_get_thread_item_info_impl_code(), 109 m_get_thread_item_info_function_mutex(), 110 m_get_thread_item_info_return_buffer_addr(LLDB_INVALID_ADDRESS), 111 m_get_thread_item_info_retbuffer_mutex() 112 { 113 } 114 115 AppleGetThreadItemInfoHandler::~AppleGetThreadItemInfoHandler () 116 { 117 } 118 119 void 120 AppleGetThreadItemInfoHandler::Detach() 121 { 122 123 if (m_process && m_process->IsAlive() && m_get_thread_item_info_return_buffer_addr != LLDB_INVALID_ADDRESS) 124 { 125 std::unique_lock<std::mutex> lock(m_get_thread_item_info_retbuffer_mutex, std::defer_lock); 126 lock.try_lock(); // Even if we don't get the lock, deallocate the buffer 127 m_process->DeallocateMemory(m_get_thread_item_info_return_buffer_addr); 128 } 129 } 130 131 // Compile our __lldb_backtrace_recording_get_thread_item_info() function (from the 132 // source above in g_get_thread_item_info_function_code) if we don't find that function in the inferior 133 // already with USE_BUILTIN_FUNCTION defined. (e.g. this would be the case for testing.) 134 // 135 // Insert the __lldb_backtrace_recording_get_thread_item_info into the inferior process if needed. 136 // 137 // Write the get_thread_item_info_arglist into the inferior's memory space to prepare for the call. 138 // 139 // Returns the address of the arguments written down in the inferior process, which can be used to 140 // make the function call. 141 142 lldb::addr_t 143 AppleGetThreadItemInfoHandler::SetupGetThreadItemInfoFunction (Thread &thread, ValueList &get_thread_item_info_arglist) 144 { 145 ThreadSP thread_sp(thread.shared_from_this()); 146 ExecutionContext exe_ctx (thread_sp); 147 Address impl_code_address; 148 DiagnosticManager diagnostics; 149 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_SYSTEM_RUNTIME)); 150 lldb::addr_t args_addr = LLDB_INVALID_ADDRESS; 151 FunctionCaller *get_thread_item_info_caller = nullptr; 152 153 // Scope for mutex locker: 154 { 155 std::lock_guard<std::mutex> guard(m_get_thread_item_info_function_mutex); 156 157 // First stage is to make the ClangUtility to hold our injected function: 158 159 if (!m_get_thread_item_info_impl_code.get()) 160 { 161 Error error; 162 if (g_get_thread_item_info_function_code != NULL) 163 { 164 m_get_thread_item_info_impl_code.reset (exe_ctx.GetTargetRef().GetUtilityFunctionForLanguage (g_get_thread_item_info_function_code, 165 eLanguageTypeC, 166 g_get_thread_item_info_function_name, 167 error)); 168 if (error.Fail()) 169 { 170 if (log) 171 log->Printf ("Failed to get UtilityFunction for get-thread-item-info introspection: %s.", 172 error.AsCString()); 173 m_get_thread_item_info_impl_code.reset(); 174 return args_addr; 175 } 176 177 if (!m_get_thread_item_info_impl_code->Install(diagnostics, exe_ctx)) 178 { 179 if (log) 180 { 181 log->Printf("Failed to install get-thread-item-info introspection."); 182 diagnostics.Dump(log); 183 } 184 185 m_get_thread_item_info_impl_code.reset(); 186 return args_addr; 187 } 188 } 189 else 190 { 191 if (log) 192 log->Printf("No get-thread-item-info introspection code found."); 193 return LLDB_INVALID_ADDRESS; 194 } 195 196 // Also make the FunctionCaller for this UtilityFunction: 197 198 ClangASTContext *clang_ast_context = thread.GetProcess()->GetTarget().GetScratchClangASTContext(); 199 CompilerType get_thread_item_info_return_type = clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); 200 201 get_thread_item_info_caller = m_get_thread_item_info_impl_code->MakeFunctionCaller (get_thread_item_info_return_type, 202 get_thread_item_info_arglist, 203 thread_sp, 204 error); 205 if (error.Fail()) 206 { 207 if (log) 208 log->Printf ("Failed to install get-thread-item-info introspection caller: %s.", error.AsCString()); 209 m_get_thread_item_info_impl_code.reset(); 210 return args_addr; 211 } 212 213 } 214 else 215 { 216 get_thread_item_info_caller = m_get_thread_item_info_impl_code->GetFunctionCaller(); 217 } 218 } 219 220 diagnostics.Clear(); 221 222 // Now write down the argument values for this particular call. This looks like it might be a race condition 223 // if other threads were calling into here, but actually it isn't because we allocate a new args structure for 224 // this call by passing args_addr = LLDB_INVALID_ADDRESS... 225 226 if (!get_thread_item_info_caller->WriteFunctionArguments(exe_ctx, args_addr, get_thread_item_info_arglist, 227 diagnostics)) 228 { 229 if (log) 230 { 231 log->Printf("Error writing get-thread-item-info function arguments"); 232 diagnostics.Dump(log); 233 } 234 return args_addr; 235 } 236 237 return args_addr; 238 } 239 240 AppleGetThreadItemInfoHandler::GetThreadItemInfoReturnInfo 241 AppleGetThreadItemInfoHandler::GetThreadItemInfo (Thread &thread, tid_t thread_id, addr_t page_to_free, uint64_t page_to_free_size, Error &error) 242 { 243 lldb::StackFrameSP thread_cur_frame = thread.GetStackFrameAtIndex(0); 244 ProcessSP process_sp (thread.CalculateProcess()); 245 TargetSP target_sp (thread.CalculateTarget()); 246 ClangASTContext *clang_ast_context = target_sp->GetScratchClangASTContext(); 247 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_SYSTEM_RUNTIME)); 248 249 GetThreadItemInfoReturnInfo return_value; 250 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 251 return_value.item_buffer_size = 0; 252 253 error.Clear(); 254 255 if (thread.SafeToCallFunctions() == false) 256 { 257 if (log) 258 log->Printf ("Not safe to call functions on thread 0x%" PRIx64, thread.GetID()); 259 error.SetErrorString ("Not safe to call functions on this thread."); 260 return return_value; 261 } 262 263 // Set up the arguments for a call to 264 265 // struct get_thread_item_info_return_values 266 // { 267 // uint64_t item_info_buffer_ptr; /* the address of the items buffer from libBacktraceRecording */ 268 // uint64_t item_info_buffer_size; /* the size of the items buffer from libBacktraceRecording */ 269 // }; 270 // 271 // void __lldb_backtrace_recording_get_thread_item_info 272 // (struct get_thread_item_info_return_values *return_buffer, 273 // int debug, 274 // void *page_to_free, 275 // uint64_t page_to_free_size) 276 277 // Where the return_buffer argument points to a 24 byte region of memory already allocated by lldb in 278 // the inferior process. 279 280 CompilerType clang_void_ptr_type = clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); 281 Value return_buffer_ptr_value; 282 return_buffer_ptr_value.SetValueType (Value::eValueTypeScalar); 283 return_buffer_ptr_value.SetCompilerType (clang_void_ptr_type); 284 285 CompilerType clang_int_type = clang_ast_context->GetBasicType(eBasicTypeInt); 286 Value debug_value; 287 debug_value.SetValueType (Value::eValueTypeScalar); 288 debug_value.SetCompilerType (clang_int_type); 289 290 CompilerType clang_uint64_type = clang_ast_context->GetBasicType(eBasicTypeUnsignedLongLong); 291 Value thread_id_value; 292 thread_id_value.SetValueType (Value::eValueTypeScalar); 293 thread_id_value.SetCompilerType (clang_uint64_type); 294 295 Value page_to_free_value; 296 page_to_free_value.SetValueType (Value::eValueTypeScalar); 297 page_to_free_value.SetCompilerType (clang_void_ptr_type); 298 299 Value page_to_free_size_value; 300 page_to_free_size_value.SetValueType (Value::eValueTypeScalar); 301 page_to_free_size_value.SetCompilerType (clang_uint64_type); 302 303 std::lock_guard<std::mutex> guard(m_get_thread_item_info_retbuffer_mutex); 304 if (m_get_thread_item_info_return_buffer_addr == LLDB_INVALID_ADDRESS) 305 { 306 addr_t bufaddr = process_sp->AllocateMemory (32, ePermissionsReadable | ePermissionsWritable, error); 307 if (!error.Success() || bufaddr == LLDB_INVALID_ADDRESS) 308 { 309 if (log) 310 log->Printf ("Failed to allocate memory for return buffer for get current queues func call"); 311 return return_value; 312 } 313 m_get_thread_item_info_return_buffer_addr = bufaddr; 314 } 315 316 ValueList argument_values; 317 318 return_buffer_ptr_value.GetScalar() = m_get_thread_item_info_return_buffer_addr; 319 argument_values.PushValue (return_buffer_ptr_value); 320 321 debug_value.GetScalar() = 0; 322 argument_values.PushValue (debug_value); 323 324 thread_id_value.GetScalar() = thread_id; 325 argument_values.PushValue (thread_id_value); 326 327 if (page_to_free != LLDB_INVALID_ADDRESS) 328 page_to_free_value.GetScalar() = page_to_free; 329 else 330 page_to_free_value.GetScalar() = 0; 331 argument_values.PushValue (page_to_free_value); 332 333 page_to_free_size_value.GetScalar() = page_to_free_size; 334 argument_values.PushValue (page_to_free_size_value); 335 336 addr_t args_addr = SetupGetThreadItemInfoFunction(thread, argument_values); 337 338 DiagnosticManager diagnostics; 339 ExecutionContext exe_ctx; 340 EvaluateExpressionOptions options; 341 FunctionCaller *get_thread_item_info_caller = nullptr; 342 343 options.SetUnwindOnError (true); 344 options.SetIgnoreBreakpoints (true); 345 options.SetStopOthers (true); 346 options.SetTimeoutUsec(500000); 347 options.SetTryAllThreads (false); 348 thread.CalculateExecutionContext (exe_ctx); 349 350 if (!m_get_thread_item_info_impl_code) 351 { 352 error.SetErrorString ("Unable to compile function to call __introspection_dispatch_thread_get_item_info"); 353 return return_value; 354 } 355 356 get_thread_item_info_caller = m_get_thread_item_info_impl_code->GetFunctionCaller(); 357 358 if (!get_thread_item_info_caller) 359 { 360 error.SetErrorString ("Unable to compile function caller for __introspection_dispatch_thread_get_item_info"); 361 return return_value; 362 } 363 364 ExpressionResults func_call_ret; 365 Value results; 366 func_call_ret = get_thread_item_info_caller->ExecuteFunction(exe_ctx, &args_addr, options, diagnostics, results); 367 if (func_call_ret != eExpressionCompleted || !error.Success()) 368 { 369 if (log) 370 log->Printf ("Unable to call __introspection_dispatch_thread_get_item_info(), got ExpressionResults %d, error contains %s", func_call_ret, error.AsCString("")); 371 error.SetErrorString ("Unable to call __introspection_dispatch_thread_get_item_info() for list of queues"); 372 return return_value; 373 } 374 375 return_value.item_buffer_ptr = m_process->ReadUnsignedIntegerFromMemory (m_get_thread_item_info_return_buffer_addr, 8, LLDB_INVALID_ADDRESS, error); 376 if (!error.Success() || return_value.item_buffer_ptr == LLDB_INVALID_ADDRESS) 377 { 378 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 379 return return_value; 380 } 381 382 return_value.item_buffer_size = m_process->ReadUnsignedIntegerFromMemory (m_get_thread_item_info_return_buffer_addr + 8, 8, 0, error); 383 384 if (!error.Success()) 385 { 386 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 387 return return_value; 388 } 389 390 if (log) 391 log->Printf ("AppleGetThreadItemInfoHandler called __introspection_dispatch_thread_get_item_info (page_to_free == 0x%" PRIx64 ", size = %" PRId64 "), returned page is at 0x%" PRIx64 ", size %" PRId64, page_to_free, page_to_free_size, return_value.item_buffer_ptr, return_value.item_buffer_size); 392 393 return return_value; 394 } 395