| //===-- AppleGetPendingItemsHandler.cpp -----------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "AppleGetPendingItemsHandler.h" |
| |
| #include "Plugins/TypeSystem/Clang/TypeSystemClang.h" |
| #include "lldb/Core/Module.h" |
| #include "lldb/Core/Value.h" |
| #include "lldb/Expression/DiagnosticManager.h" |
| #include "lldb/Expression/FunctionCaller.h" |
| #include "lldb/Expression/UtilityFunction.h" |
| #include "lldb/Symbol/Symbol.h" |
| #include "lldb/Target/ExecutionContext.h" |
| #include "lldb/Target/Process.h" |
| #include "lldb/Target/Target.h" |
| #include "lldb/Target/Thread.h" |
| #include "lldb/Utility/ConstString.h" |
| #include "lldb/Utility/Log.h" |
| #include "lldb/Utility/StreamString.h" |
| |
| using namespace lldb; |
| using namespace lldb_private; |
| |
| const char *AppleGetPendingItemsHandler::g_get_pending_items_function_name = |
| "__lldb_backtrace_recording_get_pending_items"; |
| const char *AppleGetPendingItemsHandler::g_get_pending_items_function_code = |
| " \n\ |
| extern \"C\" \n\ |
| { \n\ |
| /* \n\ |
| * mach defines \n\ |
| */ \n\ |
| \n\ |
| typedef unsigned int uint32_t; \n\ |
| typedef unsigned long long uint64_t; \n\ |
| typedef uint32_t mach_port_t; \n\ |
| typedef mach_port_t vm_map_t; \n\ |
| typedef int kern_return_t; \n\ |
| typedef uint64_t mach_vm_address_t; \n\ |
| typedef uint64_t mach_vm_size_t; \n\ |
| \n\ |
| mach_port_t mach_task_self (); \n\ |
| kern_return_t mach_vm_deallocate (vm_map_t target, mach_vm_address_t address, mach_vm_size_t size); \n\ |
| \n\ |
| /* \n\ |
| * libBacktraceRecording defines \n\ |
| */ \n\ |
| \n\ |
| typedef uint32_t queue_list_scope_t; \n\ |
| typedef void *dispatch_queue_t; \n\ |
| typedef void *introspection_dispatch_queue_info_t; \n\ |
| typedef void *introspection_dispatch_item_info_ref; \n\ |
| \n\ |
| extern uint64_t __introspection_dispatch_queue_get_pending_items (dispatch_queue_t queue, \n\ |
| introspection_dispatch_item_info_ref *returned_queues_buffer, \n\ |
| uint64_t *returned_queues_buffer_size); \n\ |
| extern int printf(const char *format, ...); \n\ |
| \n\ |
| /* \n\ |
| * return type define \n\ |
| */ \n\ |
| \n\ |
| struct get_pending_items_return_values \n\ |
| { \n\ |
| uint64_t pending_items_buffer_ptr; /* the address of the items buffer from libBacktraceRecording */ \n\ |
| uint64_t pending_items_buffer_size; /* the size of the items buffer from libBacktraceRecording */ \n\ |
| uint64_t count; /* the number of items included in the queues buffer */ \n\ |
| }; \n\ |
| \n\ |
| void __lldb_backtrace_recording_get_pending_items \n\ |
| (struct get_pending_items_return_values *return_buffer, \n\ |
| int debug, \n\ |
| uint64_t /* dispatch_queue_t */ queue, \n\ |
| void *page_to_free, \n\ |
| uint64_t page_to_free_size) \n\ |
| { \n\ |
| if (debug) \n\ |
| printf (\"entering get_pending_items with args return_buffer == %p, debug == %d, queue == 0x%llx, page_to_free == %p, page_to_free_size == 0x%llx\\n\", return_buffer, debug, queue, page_to_free, page_to_free_size); \n\ |
| if (page_to_free != 0) \n\ |
| { \n\ |
| mach_vm_deallocate (mach_task_self(), (mach_vm_address_t) page_to_free, (mach_vm_size_t) page_to_free_size); \n\ |
| } \n\ |
| \n\ |
| return_buffer->count = __introspection_dispatch_queue_get_pending_items ( \n\ |
| (void*) queue, \n\ |
| (void**)&return_buffer->pending_items_buffer_ptr, \n\ |
| &return_buffer->pending_items_buffer_size); \n\ |
| if (debug) \n\ |
| printf(\"result was count %lld\\n\", return_buffer->count); \n\ |
| } \n\ |
| } \n\ |
| "; |
| |
| AppleGetPendingItemsHandler::AppleGetPendingItemsHandler(Process *process) |
| : m_process(process), m_get_pending_items_impl_code(), |
| m_get_pending_items_function_mutex(), |
| m_get_pending_items_return_buffer_addr(LLDB_INVALID_ADDRESS), |
| m_get_pending_items_retbuffer_mutex() {} |
| |
| AppleGetPendingItemsHandler::~AppleGetPendingItemsHandler() = default; |
| |
| void AppleGetPendingItemsHandler::Detach() { |
| if (m_process && m_process->IsAlive() && |
| m_get_pending_items_return_buffer_addr != LLDB_INVALID_ADDRESS) { |
| std::unique_lock<std::mutex> lock(m_get_pending_items_retbuffer_mutex, |
| std::defer_lock); |
| (void)lock.try_lock(); // Even if we don't get the lock, deallocate the buffer |
| m_process->DeallocateMemory(m_get_pending_items_return_buffer_addr); |
| } |
| } |
| |
| // Compile our __lldb_backtrace_recording_get_pending_items() function (from |
| // the source above in g_get_pending_items_function_code) if we don't find that |
| // function in the inferior already with USE_BUILTIN_FUNCTION defined. (e.g. |
| // this would be the case for testing.) |
| // |
| // Insert the __lldb_backtrace_recording_get_pending_items into the inferior |
| // process if needed. |
| // |
| // Write the get_pending_items_arglist into the inferior's memory space to |
| // prepare for the call. |
| // |
| // Returns the address of the arguments written down in the inferior process, |
| // which can be used to make the function call. |
| |
| lldb::addr_t AppleGetPendingItemsHandler::SetupGetPendingItemsFunction( |
| Thread &thread, ValueList &get_pending_items_arglist) { |
| ThreadSP thread_sp(thread.shared_from_this()); |
| ExecutionContext exe_ctx(thread_sp); |
| DiagnosticManager diagnostics; |
| Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_SYSTEM_RUNTIME)); |
| |
| lldb::addr_t args_addr = LLDB_INVALID_ADDRESS; |
| FunctionCaller *get_pending_items_caller = nullptr; |
| |
| // Scope for mutex locker: |
| { |
| std::lock_guard<std::mutex> guard(m_get_pending_items_function_mutex); |
| |
| // First stage is to make the ClangUtility to hold our injected function: |
| |
| if (!m_get_pending_items_impl_code) { |
| if (g_get_pending_items_function_code != nullptr) { |
| auto utility_fn_or_error = exe_ctx.GetTargetRef().CreateUtilityFunction( |
| g_get_pending_items_function_code, |
| g_get_pending_items_function_name, eLanguageTypeC, exe_ctx); |
| if (!utility_fn_or_error) { |
| LLDB_LOG_ERROR(log, utility_fn_or_error.takeError(), |
| "Failed to create UtilityFunction for pending-items " |
| "introspection: {0}."); |
| return args_addr; |
| } |
| m_get_pending_items_impl_code = std::move(*utility_fn_or_error); |
| } else { |
| LLDB_LOGF(log, "No pending-items introspection code found."); |
| return LLDB_INVALID_ADDRESS; |
| } |
| |
| // Next make the runner function for our implementation utility function. |
| Status error; |
| TypeSystemClang *clang_ast_context = ScratchTypeSystemClang::GetForTarget( |
| thread.GetProcess()->GetTarget()); |
| CompilerType get_pending_items_return_type = |
| clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); |
| get_pending_items_caller = |
| m_get_pending_items_impl_code->MakeFunctionCaller( |
| get_pending_items_return_type, get_pending_items_arglist, |
| thread_sp, error); |
| if (error.Fail() || get_pending_items_caller == nullptr) { |
| LLDB_LOGF(log, |
| "Failed to install pending-items introspection function " |
| "caller: %s.", |
| error.AsCString()); |
| m_get_pending_items_impl_code.reset(); |
| return args_addr; |
| } |
| } |
| } |
| |
| diagnostics.Clear(); |
| |
| if (get_pending_items_caller == nullptr) { |
| LLDB_LOGF(log, "Failed to get get_pending_items_caller."); |
| return LLDB_INVALID_ADDRESS; |
| } |
| |
| // Now write down the argument values for this particular call. This looks |
| // like it might be a race condition if other threads were calling into here, |
| // but actually it isn't because we allocate a new args structure for this |
| // call by passing args_addr = LLDB_INVALID_ADDRESS... |
| |
| if (!get_pending_items_caller->WriteFunctionArguments( |
| exe_ctx, args_addr, get_pending_items_arglist, diagnostics)) { |
| if (log) { |
| LLDB_LOGF(log, "Error writing pending-items function arguments."); |
| diagnostics.Dump(log); |
| } |
| |
| return args_addr; |
| } |
| |
| return args_addr; |
| } |
| |
| AppleGetPendingItemsHandler::GetPendingItemsReturnInfo |
| AppleGetPendingItemsHandler::GetPendingItems(Thread &thread, addr_t queue, |
| addr_t page_to_free, |
| uint64_t page_to_free_size, |
| Status &error) { |
| lldb::StackFrameSP thread_cur_frame = thread.GetStackFrameAtIndex(0); |
| ProcessSP process_sp(thread.CalculateProcess()); |
| TargetSP target_sp(thread.CalculateTarget()); |
| TypeSystemClang *clang_ast_context = |
| ScratchTypeSystemClang::GetForTarget(*target_sp); |
| Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_SYSTEM_RUNTIME)); |
| |
| GetPendingItemsReturnInfo return_value; |
| return_value.items_buffer_ptr = LLDB_INVALID_ADDRESS; |
| return_value.items_buffer_size = 0; |
| return_value.count = 0; |
| |
| error.Clear(); |
| |
| if (!thread.SafeToCallFunctions()) { |
| LLDB_LOGF(log, "Not safe to call functions on thread 0x%" PRIx64, |
| thread.GetID()); |
| error.SetErrorString("Not safe to call functions on this thread."); |
| return return_value; |
| } |
| |
| // Set up the arguments for a call to |
| |
| // struct get_pending_items_return_values |
| // { |
| // uint64_t pending_items_buffer_ptr; /* the address of the items |
| // buffer from libBacktraceRecording */ |
| // uint64_t pending_items_buffer_size; /* the size of the items buffer |
| // from libBacktraceRecording */ |
| // uint64_t count; /* the number of items included in the |
| // queues buffer */ |
| // }; |
| // |
| // void __lldb_backtrace_recording_get_pending_items |
| // (struct |
| // get_pending_items_return_values |
| // *return_buffer, |
| // int debug, |
| // uint64_t /* dispatch_queue_t */ |
| // queue |
| // void *page_to_free, |
| // uint64_t page_to_free_size) |
| |
| // Where the return_buffer argument points to a 24 byte region of memory |
| // already allocated by lldb in the inferior process. |
| |
| CompilerType clang_void_ptr_type = |
| clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); |
| Value return_buffer_ptr_value; |
| return_buffer_ptr_value.SetValueType(Value::ValueType::Scalar); |
| return_buffer_ptr_value.SetCompilerType(clang_void_ptr_type); |
| |
| CompilerType clang_int_type = clang_ast_context->GetBasicType(eBasicTypeInt); |
| Value debug_value; |
| debug_value.SetValueType(Value::ValueType::Scalar); |
| debug_value.SetCompilerType(clang_int_type); |
| |
| CompilerType clang_uint64_type = |
| clang_ast_context->GetBasicType(eBasicTypeUnsignedLongLong); |
| Value queue_value; |
| queue_value.SetValueType(Value::ValueType::Scalar); |
| queue_value.SetCompilerType(clang_uint64_type); |
| |
| Value page_to_free_value; |
| page_to_free_value.SetValueType(Value::ValueType::Scalar); |
| page_to_free_value.SetCompilerType(clang_void_ptr_type); |
| |
| Value page_to_free_size_value; |
| page_to_free_size_value.SetValueType(Value::ValueType::Scalar); |
| page_to_free_size_value.SetCompilerType(clang_uint64_type); |
| |
| std::lock_guard<std::mutex> guard(m_get_pending_items_retbuffer_mutex); |
| if (m_get_pending_items_return_buffer_addr == LLDB_INVALID_ADDRESS) { |
| addr_t bufaddr = process_sp->AllocateMemory( |
| 32, ePermissionsReadable | ePermissionsWritable, error); |
| if (!error.Success() || bufaddr == LLDB_INVALID_ADDRESS) { |
| LLDB_LOGF(log, "Failed to allocate memory for return buffer for get " |
| "current queues func call"); |
| return return_value; |
| } |
| m_get_pending_items_return_buffer_addr = bufaddr; |
| } |
| |
| ValueList argument_values; |
| |
| return_buffer_ptr_value.GetScalar() = m_get_pending_items_return_buffer_addr; |
| argument_values.PushValue(return_buffer_ptr_value); |
| |
| debug_value.GetScalar() = 0; |
| argument_values.PushValue(debug_value); |
| |
| queue_value.GetScalar() = queue; |
| argument_values.PushValue(queue_value); |
| |
| if (page_to_free != LLDB_INVALID_ADDRESS) |
| page_to_free_value.GetScalar() = page_to_free; |
| else |
| page_to_free_value.GetScalar() = 0; |
| argument_values.PushValue(page_to_free_value); |
| |
| page_to_free_size_value.GetScalar() = page_to_free_size; |
| argument_values.PushValue(page_to_free_size_value); |
| |
| addr_t args_addr = SetupGetPendingItemsFunction(thread, argument_values); |
| |
| DiagnosticManager diagnostics; |
| ExecutionContext exe_ctx; |
| FunctionCaller *get_pending_items_caller = |
| m_get_pending_items_impl_code->GetFunctionCaller(); |
| |
| EvaluateExpressionOptions options; |
| options.SetUnwindOnError(true); |
| options.SetIgnoreBreakpoints(true); |
| options.SetStopOthers(true); |
| #if __has_feature(address_sanitizer) |
| options.SetTimeout(process_sp->GetUtilityExpressionTimeout()); |
| #else |
| options.SetTimeout(std::chrono::milliseconds(500)); |
| #endif |
| options.SetTryAllThreads(false); |
| options.SetIsForUtilityExpr(true); |
| thread.CalculateExecutionContext(exe_ctx); |
| |
| if (get_pending_items_caller == nullptr) { |
| error.SetErrorString("Unable to compile function to call " |
| "__introspection_dispatch_queue_get_pending_items"); |
| return return_value; |
| } |
| |
| ExpressionResults func_call_ret; |
| Value results; |
| func_call_ret = get_pending_items_caller->ExecuteFunction( |
| exe_ctx, &args_addr, options, diagnostics, results); |
| if (func_call_ret != eExpressionCompleted || !error.Success()) { |
| LLDB_LOGF(log, |
| "Unable to call " |
| "__introspection_dispatch_queue_get_pending_items(), got " |
| "ExpressionResults %d, error contains %s", |
| func_call_ret, error.AsCString("")); |
| error.SetErrorString("Unable to call " |
| "__introspection_dispatch_queue_get_pending_items() " |
| "for list of queues"); |
| return return_value; |
| } |
| |
| return_value.items_buffer_ptr = m_process->ReadUnsignedIntegerFromMemory( |
| m_get_pending_items_return_buffer_addr, 8, LLDB_INVALID_ADDRESS, error); |
| if (!error.Success() || |
| return_value.items_buffer_ptr == LLDB_INVALID_ADDRESS) { |
| return_value.items_buffer_ptr = LLDB_INVALID_ADDRESS; |
| return return_value; |
| } |
| |
| return_value.items_buffer_size = m_process->ReadUnsignedIntegerFromMemory( |
| m_get_pending_items_return_buffer_addr + 8, 8, 0, error); |
| |
| if (!error.Success()) { |
| return_value.items_buffer_ptr = LLDB_INVALID_ADDRESS; |
| return return_value; |
| } |
| |
| return_value.count = m_process->ReadUnsignedIntegerFromMemory( |
| m_get_pending_items_return_buffer_addr + 16, 8, 0, error); |
| if (!error.Success()) { |
| return_value.items_buffer_ptr = LLDB_INVALID_ADDRESS; |
| return return_value; |
| } |
| |
| LLDB_LOGF(log, |
| "AppleGetPendingItemsHandler called " |
| "__introspection_dispatch_queue_get_pending_items " |
| "(page_to_free == 0x%" PRIx64 ", size = %" PRId64 |
| "), returned page is at 0x%" PRIx64 ", size %" PRId64 |
| ", count = %" PRId64, |
| page_to_free, page_to_free_size, return_value.items_buffer_ptr, |
| return_value.items_buffer_size, return_value.count); |
| |
| return return_value; |
| } |
