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