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 "clang/AST/ASTContext.h" 18 #include "clang/AST/DeclCXX.h" 19 20 #include "lldb/Core/ConstString.h" 21 #include "lldb/Core/Log.h" 22 #include "lldb/Core/Module.h" 23 #include "lldb/Core/StreamString.h" 24 #include "lldb/Core/Value.h" 25 #include "lldb/Expression/ClangExpression.h" 26 #include "lldb/Expression/ClangFunction.h" 27 #include "lldb/Expression/ClangUtilityFunction.h" 28 #include "lldb/Symbol/ClangASTContext.h" 29 #include "lldb/Symbol/Symbol.h" 30 #include "lldb/Target/ExecutionContext.h" 31 #include "lldb/Target/Process.h" 32 #include "lldb/Target/Target.h" 33 #include "lldb/Target/Thread.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_function (), 109 m_get_thread_item_info_impl_code (), 110 m_get_thread_item_info_function_mutex(), 111 m_get_thread_item_info_return_buffer_addr (LLDB_INVALID_ADDRESS), 112 m_get_thread_item_info_retbuffer_mutex() 113 { 114 } 115 116 AppleGetThreadItemInfoHandler::~AppleGetThreadItemInfoHandler () 117 { 118 } 119 120 void 121 AppleGetThreadItemInfoHandler::Detach () 122 { 123 124 if (m_process && m_process->IsAlive() && m_get_thread_item_info_return_buffer_addr != LLDB_INVALID_ADDRESS) 125 { 126 Mutex::Locker locker; 127 locker.TryLock (m_get_thread_item_info_retbuffer_mutex); // Even if we don't get the lock, deallocate the buffer 128 m_process->DeallocateMemory (m_get_thread_item_info_return_buffer_addr); 129 } 130 } 131 132 // Compile our __lldb_backtrace_recording_get_thread_item_info() function (from the 133 // source above in g_get_thread_item_info_function_code) if we don't find that function in the inferior 134 // already with USE_BUILTIN_FUNCTION defined. (e.g. this would be the case for testing.) 135 // 136 // Insert the __lldb_backtrace_recording_get_thread_item_info into the inferior process if needed. 137 // 138 // Write the get_thread_item_info_arglist into the inferior's memory space to prepare for the call. 139 // 140 // Returns the address of the arguments written down in the inferior process, which can be used to 141 // make the function call. 142 143 lldb::addr_t 144 AppleGetThreadItemInfoHandler::SetupGetThreadItemInfoFunction (Thread &thread, ValueList &get_thread_item_info_arglist) 145 { 146 ExecutionContext exe_ctx (thread.shared_from_this()); 147 Address impl_code_address; 148 StreamString errors; 149 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_SYSTEM_RUNTIME)); 150 lldb::addr_t args_addr = LLDB_INVALID_ADDRESS; 151 152 // Scope for mutex locker: 153 { 154 Mutex::Locker locker(m_get_thread_item_info_function_mutex); 155 156 // First stage is to make the ClangUtility to hold our injected function: 157 158 #define USE_BUILTIN_FUNCTION 0 // Define this to 1 and we will use the get_implementation function found in the target. 159 // This is useful for debugging additions to the get_impl function 'cause you don't have 160 // to bother with string-ifying the code into g_get_thread_item_info_function_code. 161 162 if (USE_BUILTIN_FUNCTION) 163 { 164 ConstString our_utility_function_name("__lldb_backtrace_recording_get_thread_item_info"); 165 SymbolContextList sc_list; 166 167 exe_ctx.GetTargetRef().GetImages().FindSymbolsWithNameAndType (our_utility_function_name, eSymbolTypeCode, sc_list); 168 if (sc_list.GetSize() == 1) 169 { 170 SymbolContext sc; 171 sc_list.GetContextAtIndex(0, sc); 172 if (sc.symbol != NULL) 173 impl_code_address = sc.symbol->GetAddress(); 174 175 //lldb::addr_t addr = impl_code_address.GetOpcodeLoadAddress (exe_ctx.GetTargetPtr()); 176 //printf ("Getting address for our_utility_function: 0x%" PRIx64 ".\n", addr); 177 } 178 else 179 { 180 //printf ("Could not find queues introspection function address.\n"); 181 return args_addr; 182 } 183 } 184 else if (!m_get_thread_item_info_impl_code.get()) 185 { 186 if (g_get_thread_item_info_function_code != NULL) 187 { 188 m_get_thread_item_info_impl_code.reset (new ClangUtilityFunction (g_get_thread_item_info_function_code, 189 g_get_thread_item_info_function_name)); 190 if (!m_get_thread_item_info_impl_code->Install(errors, exe_ctx)) 191 { 192 if (log) 193 log->Printf ("Failed to install get-thread-item-info introspection: %s.", errors.GetData()); 194 m_get_thread_item_info_impl_code.reset(); 195 return args_addr; 196 } 197 } 198 else 199 { 200 if (log) 201 log->Printf("No get-thread-item-info introspection code found."); 202 errors.Printf ("No get-thread-item-info introspection code found."); 203 return LLDB_INVALID_ADDRESS; 204 } 205 206 impl_code_address.Clear(); 207 impl_code_address.SetOffset(m_get_thread_item_info_impl_code->StartAddress()); 208 } 209 else 210 { 211 impl_code_address.Clear(); 212 impl_code_address.SetOffset(m_get_thread_item_info_impl_code->StartAddress()); 213 } 214 215 // Next make the runner function for our implementation utility function. 216 if (!m_get_thread_item_info_function.get()) 217 { 218 ClangASTContext *clang_ast_context = thread.GetProcess()->GetTarget().GetScratchClangASTContext(); 219 ClangASTType get_thread_item_info_return_type = clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); 220 m_get_thread_item_info_function.reset(new ClangFunction (thread, 221 get_thread_item_info_return_type, 222 impl_code_address, 223 get_thread_item_info_arglist, 224 "queue-thread-item-info")); 225 226 errors.Clear(); 227 unsigned num_errors = m_get_thread_item_info_function->CompileFunction(errors); 228 if (num_errors) 229 { 230 if (log) 231 log->Printf ("Error compiling get-thread-item-info function: \"%s\".", errors.GetData()); 232 return args_addr; 233 } 234 235 errors.Clear(); 236 if (!m_get_thread_item_info_function->WriteFunctionWrapper(exe_ctx, errors)) 237 { 238 if (log) 239 log->Printf ("Error Inserting get-thread-item-info function: \"%s\".", errors.GetData()); 240 return args_addr; 241 } 242 } 243 } 244 245 errors.Clear(); 246 247 // Now write down the argument values for this particular call. This looks like it might be a race condition 248 // if other threads were calling into here, but actually it isn't because we allocate a new args structure for 249 // this call by passing args_addr = LLDB_INVALID_ADDRESS... 250 251 if (!m_get_thread_item_info_function->WriteFunctionArguments (exe_ctx, args_addr, impl_code_address, get_thread_item_info_arglist, errors)) 252 { 253 if (log) 254 log->Printf ("Error writing get-thread-item-info function arguments: \"%s\".", errors.GetData()); 255 return args_addr; 256 } 257 258 return args_addr; 259 } 260 261 AppleGetThreadItemInfoHandler::GetThreadItemInfoReturnInfo 262 AppleGetThreadItemInfoHandler::GetThreadItemInfo (Thread &thread, tid_t thread_id, addr_t page_to_free, uint64_t page_to_free_size, Error &error) 263 { 264 lldb::StackFrameSP thread_cur_frame = thread.GetStackFrameAtIndex(0); 265 ProcessSP process_sp (thread.CalculateProcess()); 266 TargetSP target_sp (thread.CalculateTarget()); 267 ClangASTContext *clang_ast_context = target_sp->GetScratchClangASTContext(); 268 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_SYSTEM_RUNTIME)); 269 270 GetThreadItemInfoReturnInfo return_value; 271 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 272 return_value.item_buffer_size = 0; 273 274 error.Clear(); 275 276 if (thread.SafeToCallFunctions() == false) 277 { 278 if (log) 279 log->Printf ("Not safe to call functions on thread 0x%" PRIx64, thread.GetID()); 280 error.SetErrorString ("Not safe to call functions on this thread."); 281 return return_value; 282 } 283 284 // Set up the arguments for a call to 285 286 // struct get_thread_item_info_return_values 287 // { 288 // uint64_t item_info_buffer_ptr; /* the address of the items buffer from libBacktraceRecording */ 289 // uint64_t item_info_buffer_size; /* the size of the items buffer from libBacktraceRecording */ 290 // }; 291 // 292 // void __lldb_backtrace_recording_get_thread_item_info 293 // (struct get_thread_item_info_return_values *return_buffer, 294 // int debug, 295 // void *page_to_free, 296 // uint64_t page_to_free_size) 297 298 // Where the return_buffer argument points to a 24 byte region of memory already allocated by lldb in 299 // the inferior process. 300 301 ClangASTType clang_void_ptr_type = clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); 302 Value return_buffer_ptr_value; 303 return_buffer_ptr_value.SetValueType (Value::eValueTypeScalar); 304 return_buffer_ptr_value.SetClangType (clang_void_ptr_type); 305 306 ClangASTType clang_int_type = clang_ast_context->GetBasicType(eBasicTypeInt); 307 Value debug_value; 308 debug_value.SetValueType (Value::eValueTypeScalar); 309 debug_value.SetClangType (clang_int_type); 310 311 ClangASTType clang_uint64_type = clang_ast_context->GetBasicType(eBasicTypeUnsignedLongLong); 312 Value thread_id_value; 313 thread_id_value.SetValueType (Value::eValueTypeScalar); 314 thread_id_value.SetClangType (clang_uint64_type); 315 316 Value page_to_free_value; 317 page_to_free_value.SetValueType (Value::eValueTypeScalar); 318 page_to_free_value.SetClangType (clang_void_ptr_type); 319 320 Value page_to_free_size_value; 321 page_to_free_size_value.SetValueType (Value::eValueTypeScalar); 322 page_to_free_size_value.SetClangType (clang_uint64_type); 323 324 325 Mutex::Locker locker(m_get_thread_item_info_retbuffer_mutex); 326 if (m_get_thread_item_info_return_buffer_addr == LLDB_INVALID_ADDRESS) 327 { 328 addr_t bufaddr = process_sp->AllocateMemory (32, ePermissionsReadable | ePermissionsWritable, error); 329 if (!error.Success() || bufaddr == LLDB_INVALID_ADDRESS) 330 { 331 if (log) 332 log->Printf ("Failed to allocate memory for return buffer for get current queues func call"); 333 return return_value; 334 } 335 m_get_thread_item_info_return_buffer_addr = bufaddr; 336 } 337 338 ValueList argument_values; 339 340 return_buffer_ptr_value.GetScalar() = m_get_thread_item_info_return_buffer_addr; 341 argument_values.PushValue (return_buffer_ptr_value); 342 343 debug_value.GetScalar() = 0; 344 argument_values.PushValue (debug_value); 345 346 thread_id_value.GetScalar() = thread_id; 347 argument_values.PushValue (thread_id_value); 348 349 if (page_to_free != LLDB_INVALID_ADDRESS) 350 page_to_free_value.GetScalar() = page_to_free; 351 else 352 page_to_free_value.GetScalar() = 0; 353 argument_values.PushValue (page_to_free_value); 354 355 page_to_free_size_value.GetScalar() = page_to_free_size; 356 argument_values.PushValue (page_to_free_size_value); 357 358 addr_t args_addr = SetupGetThreadItemInfoFunction (thread, argument_values); 359 360 StreamString errors; 361 ExecutionContext exe_ctx; 362 EvaluateExpressionOptions options; 363 options.SetUnwindOnError (true); 364 options.SetIgnoreBreakpoints (true); 365 options.SetStopOthers (true); 366 options.SetTimeoutUsec(500000); 367 options.SetTryAllThreads (false); 368 thread.CalculateExecutionContext (exe_ctx); 369 370 if (m_get_thread_item_info_function == NULL) 371 { 372 error.SetErrorString ("Unable to compile function to call __introspection_dispatch_thread_get_item_info"); 373 return return_value; 374 } 375 376 377 ExpressionResults func_call_ret; 378 Value results; 379 func_call_ret = m_get_thread_item_info_function->ExecuteFunction (exe_ctx, &args_addr, options, errors, results); 380 if (func_call_ret != eExpressionCompleted || !error.Success()) 381 { 382 if (log) 383 log->Printf ("Unable to call __introspection_dispatch_thread_get_item_info(), got ExpressionResults %d, error contains %s", func_call_ret, error.AsCString("")); 384 error.SetErrorString ("Unable to call __introspection_dispatch_thread_get_item_info() for list of queues"); 385 return return_value; 386 } 387 388 return_value.item_buffer_ptr = m_process->ReadUnsignedIntegerFromMemory (m_get_thread_item_info_return_buffer_addr, 8, LLDB_INVALID_ADDRESS, error); 389 if (!error.Success() || return_value.item_buffer_ptr == LLDB_INVALID_ADDRESS) 390 { 391 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 392 return return_value; 393 } 394 395 return_value.item_buffer_size = m_process->ReadUnsignedIntegerFromMemory (m_get_thread_item_info_return_buffer_addr + 8, 8, 0, error); 396 397 if (!error.Success()) 398 { 399 return_value.item_buffer_ptr = LLDB_INVALID_ADDRESS; 400 return return_value; 401 } 402 403 if (log) 404 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); 405 406 return return_value; 407 } 408