1 //===-- AppleGetThreadItemInfoHandler.cpp -------------------------------*- C++ 2 //-*-===// 3 // 4 // The LLVM Compiler Infrastructure 5 // 6 // This file is distributed under the University of Illinois Open Source 7 // License. See LICENSE.TXT for details. 8 // 9 //===----------------------------------------------------------------------===// 10 11 #include "AppleGetThreadItemInfoHandler.h" 12 13 // C Includes 14 // C++ Includes 15 // Other libraries and framework includes 16 // Project includes 17 18 #include "lldb/Core/ConstString.h" 19 #include "lldb/Core/Log.h" 20 #include "lldb/Core/Module.h" 21 #include "lldb/Core/StreamString.h" 22 #include "lldb/Core/Value.h" 23 #include "lldb/Expression/DiagnosticManager.h" 24 #include "lldb/Expression/Expression.h" 25 #include "lldb/Expression/FunctionCaller.h" 26 #include "lldb/Expression/UtilityFunction.h" 27 #include "lldb/Symbol/ClangASTContext.h" 28 #include "lldb/Symbol/Symbol.h" 29 #include "lldb/Target/ExecutionContext.h" 30 #include "lldb/Target/Process.h" 31 #include "lldb/Target/StackFrame.h" 32 #include "lldb/Target/Target.h" 33 #include "lldb/Target/Thread.h" 34 #include "lldb/lldb-private.h" 35 36 using namespace lldb; 37 using namespace lldb_private; 38 39 const char 40 *AppleGetThreadItemInfoHandler::g_get_thread_item_info_function_name = 41 "__lldb_backtrace_recording_get_thread_item_info"; 42 const char 43 *AppleGetThreadItemInfoHandler::g_get_thread_item_info_function_code = 44 " \n\ 45 extern \"C\" \n\ 46 { \n\ 47 /* \n\ 48 * mach defines \n\ 49 */ \n\ 50 \n\ 51 typedef unsigned int uint32_t; \n\ 52 typedef unsigned long long uint64_t; \n\ 53 typedef uint32_t mach_port_t; \n\ 54 typedef mach_port_t vm_map_t; \n\ 55 typedef int kern_return_t; \n\ 56 typedef uint64_t mach_vm_address_t; \n\ 57 typedef uint64_t mach_vm_size_t; \n\ 58 \n\ 59 mach_port_t mach_task_self (); \n\ 60 kern_return_t mach_vm_deallocate (vm_map_t target, mach_vm_address_t address, mach_vm_size_t size); \n\ 61 \n\ 62 typedef void *pthread_t; \n\ 63 extern int printf(const char *format, ...); \n\ 64 extern pthread_t pthread_self(void); \n\ 65 \n\ 66 /* \n\ 67 * libBacktraceRecording defines \n\ 68 */ \n\ 69 \n\ 70 typedef uint32_t queue_list_scope_t; \n\ 71 typedef void *dispatch_queue_t; \n\ 72 typedef void *introspection_dispatch_queue_info_t; \n\ 73 typedef void *introspection_dispatch_item_info_ref; \n\ 74 \n\ 75 extern void __introspection_dispatch_thread_get_item_info (uint64_t thread_id, \n\ 76 introspection_dispatch_item_info_ref *returned_queues_buffer, \n\ 77 uint64_t *returned_queues_buffer_size); \n\ 78 \n\ 79 /* \n\ 80 * return type define \n\ 81 */ \n\ 82 \n\ 83 struct get_thread_item_info_return_values \n\ 84 { \n\ 85 uint64_t item_info_buffer_ptr; /* the address of the items buffer from libBacktraceRecording */ \n\ 86 uint64_t item_info_buffer_size; /* the size of the items buffer from libBacktraceRecording */ \n\ 87 }; \n\ 88 \n\ 89 void __lldb_backtrace_recording_get_thread_item_info \n\ 90 (struct get_thread_item_info_return_values *return_buffer, \n\ 91 int debug, \n\ 92 uint64_t thread_id, \n\ 93 void *page_to_free, \n\ 94 uint64_t page_to_free_size) \n\ 95 { \n\ 96 void *pthread_id = pthread_self (); \n\ 97 if (debug) \n\ 98 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\ 99 if (page_to_free != 0) \n\ 100 { \n\ 101 mach_vm_deallocate (mach_task_self(), (mach_vm_address_t) page_to_free, (mach_vm_size_t) page_to_free_size); \n\ 102 } \n\ 103 \n\ 104 __introspection_dispatch_thread_get_item_info (thread_id, \n\ 105 (void**)&return_buffer->item_info_buffer_ptr, \n\ 106 &return_buffer->item_info_buffer_size); \n\ 107 } \n\ 108 } \n\ 109 "; 110 111 AppleGetThreadItemInfoHandler::AppleGetThreadItemInfoHandler(Process *process) 112 : m_process(process), m_get_thread_item_info_impl_code(), 113 m_get_thread_item_info_function_mutex(), 114 m_get_thread_item_info_return_buffer_addr(LLDB_INVALID_ADDRESS), 115 m_get_thread_item_info_retbuffer_mutex() {} 116 117 AppleGetThreadItemInfoHandler::~AppleGetThreadItemInfoHandler() {} 118 119 void AppleGetThreadItemInfoHandler::Detach() { 120 121 if (m_process && m_process->IsAlive() && 122 m_get_thread_item_info_return_buffer_addr != LLDB_INVALID_ADDRESS) { 123 std::unique_lock<std::mutex> lock(m_get_thread_item_info_retbuffer_mutex, 124 std::defer_lock); 125 lock.try_lock(); // Even if we don't get the lock, deallocate the buffer 126 m_process->DeallocateMemory(m_get_thread_item_info_return_buffer_addr); 127 } 128 } 129 130 // Compile our __lldb_backtrace_recording_get_thread_item_info() function (from 131 // the 132 // source above in g_get_thread_item_info_function_code) if we don't find that 133 // function in the inferior 134 // already with USE_BUILTIN_FUNCTION defined. (e.g. this would be the case for 135 // testing.) 136 // 137 // Insert the __lldb_backtrace_recording_get_thread_item_info into the inferior 138 // process if needed. 139 // 140 // Write the get_thread_item_info_arglist into the inferior's memory space to 141 // prepare for the call. 142 // 143 // Returns the address of the arguments written down in the inferior process, 144 // which can be used to 145 // make the function call. 146 147 lldb::addr_t AppleGetThreadItemInfoHandler::SetupGetThreadItemInfoFunction( 148 Thread &thread, ValueList &get_thread_item_info_arglist) { 149 ThreadSP thread_sp(thread.shared_from_this()); 150 ExecutionContext exe_ctx(thread_sp); 151 Address impl_code_address; 152 DiagnosticManager diagnostics; 153 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_SYSTEM_RUNTIME)); 154 lldb::addr_t args_addr = LLDB_INVALID_ADDRESS; 155 FunctionCaller *get_thread_item_info_caller = nullptr; 156 157 // Scope for mutex locker: 158 { 159 std::lock_guard<std::mutex> guard(m_get_thread_item_info_function_mutex); 160 161 // First stage is to make the ClangUtility to hold our injected function: 162 163 if (!m_get_thread_item_info_impl_code.get()) { 164 Error error; 165 if (g_get_thread_item_info_function_code != NULL) { 166 m_get_thread_item_info_impl_code.reset( 167 exe_ctx.GetTargetRef().GetUtilityFunctionForLanguage( 168 g_get_thread_item_info_function_code, eLanguageTypeC, 169 g_get_thread_item_info_function_name, error)); 170 if (error.Fail()) { 171 if (log) 172 log->Printf("Failed to get UtilityFunction for " 173 "get-thread-item-info introspection: %s.", 174 error.AsCString()); 175 m_get_thread_item_info_impl_code.reset(); 176 return args_addr; 177 } 178 179 if (!m_get_thread_item_info_impl_code->Install(diagnostics, exe_ctx)) { 180 if (log) { 181 log->Printf( 182 "Failed to install get-thread-item-info introspection."); 183 diagnostics.Dump(log); 184 } 185 186 m_get_thread_item_info_impl_code.reset(); 187 return args_addr; 188 } 189 } else { 190 if (log) 191 log->Printf("No get-thread-item-info introspection code found."); 192 return LLDB_INVALID_ADDRESS; 193 } 194 195 // Also make the FunctionCaller for this UtilityFunction: 196 197 ClangASTContext *clang_ast_context = 198 thread.GetProcess()->GetTarget().GetScratchClangASTContext(); 199 CompilerType get_thread_item_info_return_type = 200 clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); 201 202 get_thread_item_info_caller = 203 m_get_thread_item_info_impl_code->MakeFunctionCaller( 204 get_thread_item_info_return_type, get_thread_item_info_arglist, 205 thread_sp, error); 206 if (error.Fail()) { 207 if (log) 208 log->Printf("Failed to install get-thread-item-info introspection " 209 "caller: %s.", 210 error.AsCString()); 211 m_get_thread_item_info_impl_code.reset(); 212 return args_addr; 213 } 214 215 } else { 216 get_thread_item_info_caller = 217 m_get_thread_item_info_impl_code->GetFunctionCaller(); 218 } 219 } 220 221 diagnostics.Clear(); 222 223 // Now write down the argument values for this particular call. This looks 224 // like it might be a race condition 225 // if other threads were calling into here, but actually it isn't because we 226 // allocate a new args structure for 227 // this call by passing args_addr = LLDB_INVALID_ADDRESS... 228 229 if (!get_thread_item_info_caller->WriteFunctionArguments( 230 exe_ctx, args_addr, get_thread_item_info_arglist, diagnostics)) { 231 if (log) { 232 log->Printf("Error writing get-thread-item-info function arguments"); 233 diagnostics.Dump(log); 234 } 235 return args_addr; 236 } 237 238 return args_addr; 239 } 240 241 AppleGetThreadItemInfoHandler::GetThreadItemInfoReturnInfo 242 AppleGetThreadItemInfoHandler::GetThreadItemInfo(Thread &thread, 243 tid_t thread_id, 244 addr_t page_to_free, 245 uint64_t page_to_free_size, 246 Error &error) { 247 lldb::StackFrameSP thread_cur_frame = thread.GetStackFrameAtIndex(0); 248 ProcessSP process_sp(thread.CalculateProcess()); 249 TargetSP target_sp(thread.CalculateTarget()); 250 ClangASTContext *clang_ast_context = target_sp->GetScratchClangASTContext(); 251 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_SYSTEM_RUNTIME)); 252 253 GetThreadItemInfoReturnInfo return_value; 254 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 255 return_value.item_buffer_size = 0; 256 257 error.Clear(); 258 259 if (thread.SafeToCallFunctions() == false) { 260 if (log) 261 log->Printf("Not safe to call functions on thread 0x%" PRIx64, 262 thread.GetID()); 263 error.SetErrorString("Not safe to call functions on this thread."); 264 return return_value; 265 } 266 267 // Set up the arguments for a call to 268 269 // struct get_thread_item_info_return_values 270 // { 271 // uint64_t item_info_buffer_ptr; /* the address of the items buffer 272 // from libBacktraceRecording */ 273 // uint64_t item_info_buffer_size; /* the size of the items buffer from 274 // libBacktraceRecording */ 275 // }; 276 // 277 // void __lldb_backtrace_recording_get_thread_item_info 278 // (struct 279 // get_thread_item_info_return_values 280 // *return_buffer, 281 // int debug, 282 // void *page_to_free, 283 // uint64_t page_to_free_size) 284 285 // Where the return_buffer argument points to a 24 byte region of memory 286 // already allocated by lldb in 287 // the inferior process. 288 289 CompilerType clang_void_ptr_type = 290 clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); 291 Value return_buffer_ptr_value; 292 return_buffer_ptr_value.SetValueType(Value::eValueTypeScalar); 293 return_buffer_ptr_value.SetCompilerType(clang_void_ptr_type); 294 295 CompilerType clang_int_type = clang_ast_context->GetBasicType(eBasicTypeInt); 296 Value debug_value; 297 debug_value.SetValueType(Value::eValueTypeScalar); 298 debug_value.SetCompilerType(clang_int_type); 299 300 CompilerType clang_uint64_type = 301 clang_ast_context->GetBasicType(eBasicTypeUnsignedLongLong); 302 Value thread_id_value; 303 thread_id_value.SetValueType(Value::eValueTypeScalar); 304 thread_id_value.SetCompilerType(clang_uint64_type); 305 306 Value page_to_free_value; 307 page_to_free_value.SetValueType(Value::eValueTypeScalar); 308 page_to_free_value.SetCompilerType(clang_void_ptr_type); 309 310 Value page_to_free_size_value; 311 page_to_free_size_value.SetValueType(Value::eValueTypeScalar); 312 page_to_free_size_value.SetCompilerType(clang_uint64_type); 313 314 std::lock_guard<std::mutex> guard(m_get_thread_item_info_retbuffer_mutex); 315 if (m_get_thread_item_info_return_buffer_addr == LLDB_INVALID_ADDRESS) { 316 addr_t bufaddr = process_sp->AllocateMemory( 317 32, ePermissionsReadable | ePermissionsWritable, error); 318 if (!error.Success() || bufaddr == LLDB_INVALID_ADDRESS) { 319 if (log) 320 log->Printf("Failed to allocate memory for return buffer for get " 321 "current queues func call"); 322 return return_value; 323 } 324 m_get_thread_item_info_return_buffer_addr = bufaddr; 325 } 326 327 ValueList argument_values; 328 329 return_buffer_ptr_value.GetScalar() = 330 m_get_thread_item_info_return_buffer_addr; 331 argument_values.PushValue(return_buffer_ptr_value); 332 333 debug_value.GetScalar() = 0; 334 argument_values.PushValue(debug_value); 335 336 thread_id_value.GetScalar() = thread_id; 337 argument_values.PushValue(thread_id_value); 338 339 if (page_to_free != LLDB_INVALID_ADDRESS) 340 page_to_free_value.GetScalar() = page_to_free; 341 else 342 page_to_free_value.GetScalar() = 0; 343 argument_values.PushValue(page_to_free_value); 344 345 page_to_free_size_value.GetScalar() = page_to_free_size; 346 argument_values.PushValue(page_to_free_size_value); 347 348 addr_t args_addr = SetupGetThreadItemInfoFunction(thread, argument_values); 349 350 DiagnosticManager diagnostics; 351 ExecutionContext exe_ctx; 352 EvaluateExpressionOptions options; 353 FunctionCaller *get_thread_item_info_caller = nullptr; 354 355 options.SetUnwindOnError(true); 356 options.SetIgnoreBreakpoints(true); 357 options.SetStopOthers(true); 358 options.SetTimeoutUsec(500000); 359 options.SetTryAllThreads(false); 360 thread.CalculateExecutionContext(exe_ctx); 361 362 if (!m_get_thread_item_info_impl_code) { 363 error.SetErrorString("Unable to compile function to call " 364 "__introspection_dispatch_thread_get_item_info"); 365 return return_value; 366 } 367 368 get_thread_item_info_caller = 369 m_get_thread_item_info_impl_code->GetFunctionCaller(); 370 371 if (!get_thread_item_info_caller) { 372 error.SetErrorString("Unable to compile function caller for " 373 "__introspection_dispatch_thread_get_item_info"); 374 return return_value; 375 } 376 377 ExpressionResults func_call_ret; 378 Value results; 379 func_call_ret = get_thread_item_info_caller->ExecuteFunction( 380 exe_ctx, &args_addr, options, diagnostics, results); 381 if (func_call_ret != eExpressionCompleted || !error.Success()) { 382 if (log) 383 log->Printf("Unable to call " 384 "__introspection_dispatch_thread_get_item_info(), got " 385 "ExpressionResults %d, error contains %s", 386 func_call_ret, error.AsCString("")); 387 error.SetErrorString("Unable to call " 388 "__introspection_dispatch_thread_get_item_info() for " 389 "list of queues"); 390 return return_value; 391 } 392 393 return_value.item_buffer_ptr = m_process->ReadUnsignedIntegerFromMemory( 394 m_get_thread_item_info_return_buffer_addr, 8, LLDB_INVALID_ADDRESS, 395 error); 396 if (!error.Success() || 397 return_value.item_buffer_ptr == LLDB_INVALID_ADDRESS) { 398 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 399 return return_value; 400 } 401 402 return_value.item_buffer_size = m_process->ReadUnsignedIntegerFromMemory( 403 m_get_thread_item_info_return_buffer_addr + 8, 8, 0, error); 404 405 if (!error.Success()) { 406 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 407 return return_value; 408 } 409 410 if (log) 411 log->Printf("AppleGetThreadItemInfoHandler called " 412 "__introspection_dispatch_thread_get_item_info (page_to_free " 413 "== 0x%" PRIx64 ", size = %" PRId64 414 "), returned page is at 0x%" PRIx64 ", size %" PRId64, 415 page_to_free, page_to_free_size, return_value.item_buffer_ptr, 416 return_value.item_buffer_size); 417 418 return return_value; 419 } 420