https://github.com/JDevlieghere updated https://github.com/llvm/llvm-project/pull/138219
>From e7333489e50b1efe16203e8fd7b6dc7f2dcd4439 Mon Sep 17 00:00:00 2001 From: Jonas Devlieghere <jo...@devlieghere.com> Date: Fri, 2 May 2025 09:59:01 -0700 Subject: [PATCH] [lldb-dap] Change the launch sequence This PR changes how we treat the launch sequence in lldb-dap. - Send the initialized event after we finish handling the initialize request, rather than after we finish attaching or launching. - Delay handling the launch and attach request until we have handled the configurationDone request. The latter is now largely a NO-OP and only exists to signal lldb-dap that it can handle the launch and attach requests. - Delay handling the initial threads requests until we have handled the launch or attach request. - Make all attaching and launching asynchronous, including when we have attach or launch commands. That removes the need to synchronize between the request and event thread. Background: https://discourse.llvm.org/t/reliability-of-the-lldb-dap-tests/86125 --- lldb/tools/lldb-dap/DAP.cpp | 53 +++++++--- lldb/tools/lldb-dap/DAP.h | 6 +- lldb/tools/lldb-dap/EventHelper.cpp | 2 +- .../lldb-dap/Handler/AttachRequestHandler.cpp | 98 ++++++++++--------- .../ConfigurationDoneRequestHandler.cpp | 14 +-- .../Handler/InitializeRequestHandler.cpp | 44 ++++----- .../lldb-dap/Handler/LaunchRequestHandler.cpp | 2 - .../tools/lldb-dap/Handler/RequestHandler.cpp | 69 ++++++++----- lldb/tools/lldb-dap/Handler/RequestHandler.h | 1 + 9 files changed, 163 insertions(+), 126 deletions(-) diff --git a/lldb/tools/lldb-dap/DAP.cpp b/lldb/tools/lldb-dap/DAP.cpp index 4cb0d8e49004c..470cde5ae69b0 100644 --- a/lldb/tools/lldb-dap/DAP.cpp +++ b/lldb/tools/lldb-dap/DAP.cpp @@ -84,8 +84,8 @@ DAP::DAP(Log *log, const ReplMode default_repl_mode, : log(log), transport(transport), broadcaster("lldb-dap"), exception_breakpoints(), focus_tid(LLDB_INVALID_THREAD_ID), stop_at_entry(false), is_attach(false), - restarting_process_id(LLDB_INVALID_PROCESS_ID), - configuration_done_sent(false), waiting_for_run_in_terminal(false), + restarting_process_id(LLDB_INVALID_PROCESS_ID), configuration_done(false), + waiting_for_run_in_terminal(false), progress_event_reporter( [&](const ProgressEvent &event) { SendJSON(event.ToJSON()); }), reverse_request_seq(0), repl_mode(default_repl_mode) { @@ -893,10 +893,23 @@ llvm::Error DAP::Loop() { return errWrapper; } + // The launch sequence is special and we need to carefully handle + // packets in the right order. The launch and attach requests cannot + // be answered until we've gotten the confgigurationDone request. We + // can't answer the threads request until we've successfully launched + // or attached. + bool is_part_of_launch_sequence = false; + if (const protocol::Request *req = - std::get_if<protocol::Request>(&*next); - req && req->command == "disconnect") { - disconnecting = true; + std::get_if<protocol::Request>(&*next)) { + if (req->command == "disconnect") + disconnecting = true; + if (!configuration_done) { + if (req->command == "launch" || req->command == "attach") + is_part_of_launch_sequence = true; + if (req->command == "threads" && !m_launch_sequence_queue.empty()) + is_part_of_launch_sequence = true; + } } const std::optional<CancelArguments> cancel_args = @@ -924,7 +937,10 @@ llvm::Error DAP::Loop() { { std::lock_guard<std::mutex> guard(m_queue_mutex); - m_queue.push_back(std::move(*next)); + if (is_part_of_launch_sequence) + m_launch_sequence_queue.push_back(std::move(*next)); + else + m_queue.push_back(std::move(*next)); } m_queue_cv.notify_one(); } @@ -938,15 +954,30 @@ llvm::Error DAP::Loop() { StopEventHandlers(); }); - while (!disconnecting || !m_queue.empty()) { + while (true) { std::unique_lock<std::mutex> lock(m_queue_mutex); - m_queue_cv.wait(lock, [&] { return disconnecting || !m_queue.empty(); }); + m_queue_cv.wait(lock, [&] { + return disconnecting || !m_queue.empty() || + (!m_launch_sequence_queue.empty() && configuration_done); + }); - if (m_queue.empty()) + if (disconnecting) break; - Message next = m_queue.front(); - m_queue.pop_front(); + bool is_launch_seqeuence = + !m_launch_sequence_queue.empty() && configuration_done; + + auto &active_queue = + is_launch_seqeuence ? m_launch_sequence_queue : m_queue; + + assert(!active_queue.empty() && + "shouldn't have gotten past the wait with an empty queue"); + + Message next = active_queue.front(); + active_queue.pop_front(); + + // Unlock while we're processing the event. + lock.unlock(); if (!HandleObject(next)) return llvm::createStringError(llvm::inconvertibleErrorCode(), diff --git a/lldb/tools/lldb-dap/DAP.h b/lldb/tools/lldb-dap/DAP.h index 88eedb0860cf1..4f038b66757c8 100644 --- a/lldb/tools/lldb-dap/DAP.h +++ b/lldb/tools/lldb-dap/DAP.h @@ -188,7 +188,7 @@ struct DAP { // shutting down the entire adapter. When we're restarting, we keep the id of // the old process here so we can detect this case and keep running. lldb::pid_t restarting_process_id; - bool configuration_done_sent; + bool configuration_done; llvm::StringMap<std::unique_ptr<BaseRequestHandler>> request_handlers; bool waiting_for_run_in_terminal; ProgressEventReporter progress_event_reporter; @@ -417,8 +417,10 @@ struct DAP { lldb::SBMutex GetAPIMutex() const { return target.GetAPIMutex(); } private: - std::mutex m_queue_mutex; + /// Queue for all incoming messages. std::deque<protocol::Message> m_queue; + std::deque<protocol::Message> m_launch_sequence_queue; + std::mutex m_queue_mutex; std::condition_variable m_queue_cv; std::mutex m_cancelled_requests_mutex; diff --git a/lldb/tools/lldb-dap/EventHelper.cpp b/lldb/tools/lldb-dap/EventHelper.cpp index 2c659f39f4b66..ed2d8700c26b0 100644 --- a/lldb/tools/lldb-dap/EventHelper.cpp +++ b/lldb/tools/lldb-dap/EventHelper.cpp @@ -222,7 +222,7 @@ void SendContinuedEvent(DAP &dap) { // If the focus thread is not set then we haven't reported any thread status // to the client, so nothing to report. - if (!dap.configuration_done_sent || dap.focus_tid == LLDB_INVALID_THREAD_ID) { + if (!dap.configuration_done || dap.focus_tid == LLDB_INVALID_THREAD_ID) { return; } diff --git a/lldb/tools/lldb-dap/Handler/AttachRequestHandler.cpp b/lldb/tools/lldb-dap/Handler/AttachRequestHandler.cpp index 7084d30f2625b..26bd46e587c6d 100644 --- a/lldb/tools/lldb-dap/Handler/AttachRequestHandler.cpp +++ b/lldb/tools/lldb-dap/Handler/AttachRequestHandler.cpp @@ -137,55 +137,67 @@ void AttachRequestHandler::operator()(const llvm::json::Object &request) const { dap.SendOutput(OutputType::Console, llvm::StringRef(attach_msg, attach_msg_len)); } - if (attachCommands.empty()) { - // No "attachCommands", just attach normally. - // Disable async events so the attach will be successful when we return from - // the launch call and the launch will happen synchronously + { + // Perform the launch in synchronous mode so that we don't have to worry + // about process state changes during the launch. ScopeSyncMode scope_sync_mode(dap.debugger); - - if (core_file.empty()) { - if ((pid != LLDB_INVALID_PROCESS_ID) && - (gdb_remote_port != invalid_port)) { - // If both pid and port numbers are specified. - error.SetErrorString("The user can't specify both pid and port"); - } else if (gdb_remote_port != invalid_port) { - // If port is specified and pid is not. - lldb::SBListener listener = dap.debugger.GetListener(); - - // If the user hasn't provided the hostname property, default localhost - // being used. - std::string connect_url = - llvm::formatv("connect://{0}:", gdb_remote_hostname); - connect_url += std::to_string(gdb_remote_port); - dap.target.ConnectRemote(listener, connect_url.c_str(), "gdb-remote", - error); + if (attachCommands.empty()) { + // No "attachCommands", just attach normally. + if (core_file.empty()) { + if ((pid != LLDB_INVALID_PROCESS_ID) && + (gdb_remote_port != invalid_port)) { + // If both pid and port numbers are specified. + error.SetErrorString("The user can't specify both pid and port"); + } else if (gdb_remote_port != invalid_port) { + // If port is specified and pid is not. + lldb::SBListener listener = dap.debugger.GetListener(); + + // If the user hasn't provided the hostname property, default + // localhost being used. + std::string connect_url = + llvm::formatv("connect://{0}:", gdb_remote_hostname); + connect_url += std::to_string(gdb_remote_port); + dap.target.ConnectRemote(listener, connect_url.c_str(), "gdb-remote", + error); + } else { + // Attach by process name or id. + dap.target.Attach(attach_info, error); + } } else { - // Attach by process name or id. - dap.target.Attach(attach_info, error); + dap.target.LoadCore(core_file.data(), error); } } else { - dap.target.LoadCore(core_file.data(), error); - } - } else { - // We have "attachCommands" that are a set of commands that are expected - // to execute the commands after which a process should be created. If there - // is no valid process after running these commands, we have failed. - if (llvm::Error err = dap.RunAttachCommands(attachCommands)) { - response["success"] = false; - EmplaceSafeString(response, "message", llvm::toString(std::move(err))); - dap.SendJSON(llvm::json::Value(std::move(response))); - return; + // We have "attachCommands" that are a set of commands that are expected + // to execute the commands after which a process should be created. If + // there is no valid process after running these commands, we have failed. + if (llvm::Error err = dap.RunAttachCommands(attachCommands)) { + response["success"] = false; + EmplaceSafeString(response, "message", llvm::toString(std::move(err))); + dap.SendJSON(llvm::json::Value(std::move(response))); + return; + } + // The custom commands might have created a new target so we should use + // the selected target after these commands are run. + dap.target = dap.debugger.GetSelectedTarget(); } - // The custom commands might have created a new target so we should use the - // selected target after these commands are run. - dap.target = dap.debugger.GetSelectedTarget(); - - // Make sure the process is attached and stopped before proceeding as the - // the launch commands are not run using the synchronous mode. - error = dap.WaitForProcessToStop(std::chrono::seconds(timeout_seconds)); } + // Make sure the process is attached and stopped. + error = dap.WaitForProcessToStop(std::chrono::seconds(timeout_seconds)); + + // Clients can request a baseline of currently existing threads after + // we acknowledge the configurationDone request. + // Client requests the baseline of currently existing threads after + // a successful or attach by sending a 'threads' request + // right after receiving the configurationDone response. + // Obtain the list of threads before we resume the process + dap.initial_thread_list = + GetThreads(dap.target.GetProcess(), dap.thread_format); + + if (!dap.stop_at_entry) + dap.target.GetProcess().Continue(); + if (error.Success() && core_file.empty()) { auto attached_pid = dap.target.GetProcess().GetProcessID(); if (attached_pid == LLDB_INVALID_PROCESS_ID) { @@ -204,10 +216,8 @@ void AttachRequestHandler::operator()(const llvm::json::Object &request) const { } dap.SendJSON(llvm::json::Value(std::move(response))); - if (error.Success()) { + if (error.Success()) SendProcessEvent(dap, Attach); - dap.SendJSON(CreateEventObject("initialized")); - } } } // namespace lldb_dap diff --git a/lldb/tools/lldb-dap/Handler/ConfigurationDoneRequestHandler.cpp b/lldb/tools/lldb-dap/Handler/ConfigurationDoneRequestHandler.cpp index f39bbdefdbb95..a10cd0c832782 100644 --- a/lldb/tools/lldb-dap/Handler/ConfigurationDoneRequestHandler.cpp +++ b/lldb/tools/lldb-dap/Handler/ConfigurationDoneRequestHandler.cpp @@ -47,21 +47,11 @@ namespace lldb_dap { void ConfigurationDoneRequestHandler::operator()( const llvm::json::Object &request) const { + dap.configuration_done = true; + llvm::json::Object response; FillResponse(request, response); dap.SendJSON(llvm::json::Value(std::move(response))); - dap.configuration_done_sent = true; - if (dap.stop_at_entry) - SendThreadStoppedEvent(dap); - else { - // Client requests the baseline of currently existing threads after - // a successful launch or attach by sending a 'threads' request - // right after receiving the configurationDone response. - // Obtain the list of threads before we resume the process - dap.initial_thread_list = - GetThreads(dap.target.GetProcess(), dap.thread_format); - dap.target.GetProcess().Continue(); - } } } // namespace lldb_dap diff --git a/lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp b/lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp index ce34c52bcc334..aa947d3cb5ab9 100644 --- a/lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp +++ b/lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp @@ -140,43 +140,28 @@ static void EventThreadFunction(DAP &dap) { lldb::SBProcess process = lldb::SBProcess::GetProcessFromEvent(event); if (event_mask & lldb::SBProcess::eBroadcastBitStateChanged) { auto state = lldb::SBProcess::GetStateFromEvent(event); + + DAP_LOG(dap.log, "State = {0}", state); switch (state) { + case lldb::eStateConnected: + case lldb::eStateDetached: case lldb::eStateInvalid: - // Not a state event - break; case lldb::eStateUnloaded: break; - case lldb::eStateConnected: - break; case lldb::eStateAttaching: - break; - case lldb::eStateLaunching: - break; - case lldb::eStateStepping: - break; case lldb::eStateCrashed: - break; - case lldb::eStateDetached: - break; - case lldb::eStateSuspended: - break; + case lldb::eStateLaunching: case lldb::eStateStopped: - // We launch and attach in synchronous mode then the first stop - // event will not be delivered. If we use "launchCommands" during a - // launch or "attachCommands" during an attach we might some process - // stop events which we do not want to send an event for. We will - // manually send a stopped event in request_configurationDone(...) - // so don't send any before then. - if (dap.configuration_done_sent) { - // Only report a stopped event if the process was not - // automatically restarted. - if (!lldb::SBProcess::GetRestartedFromEvent(event)) { - SendStdOutStdErr(dap, process); - SendThreadStoppedEvent(dap); - } + case lldb::eStateSuspended: + // Only report a stopped event if the process was not + // automatically restarted. + if (!lldb::SBProcess::GetRestartedFromEvent(event)) { + SendStdOutStdErr(dap, process); + SendThreadStoppedEvent(dap); } break; case lldb::eStateRunning: + case lldb::eStateStepping: dap.WillContinue(); SendContinuedEvent(dap); break; @@ -284,6 +269,7 @@ llvm::Expected<InitializeResponseBody> InitializeRequestHandler::Run( // Do not source init files until in/out/err are configured. dap.debugger = lldb::SBDebugger::Create(false); dap.debugger.SetInputFile(dap.in); + dap.target = dap.debugger.GetDummyTarget(); llvm::Expected<int> out_fd = dap.out.GetWriteFileDescriptor(); if (!out_fd) @@ -338,4 +324,8 @@ llvm::Expected<InitializeResponseBody> InitializeRequestHandler::Run( return dap.GetCapabilities(); } +void InitializeRequestHandler::PostRun() const { + dap.SendJSON(CreateEventObject("initialized")); +} + } // namespace lldb_dap diff --git a/lldb/tools/lldb-dap/Handler/LaunchRequestHandler.cpp b/lldb/tools/lldb-dap/Handler/LaunchRequestHandler.cpp index 3e4532e754ec6..ffd61b040e55f 100644 --- a/lldb/tools/lldb-dap/Handler/LaunchRequestHandler.cpp +++ b/lldb/tools/lldb-dap/Handler/LaunchRequestHandler.cpp @@ -72,8 +72,6 @@ void LaunchRequestHandler::PostRun() const { // Attach happens when launching with runInTerminal. SendProcessEvent(dap, dap.is_attach ? Attach : Launch); } - - dap.SendJSON(CreateEventObject("initialized")); } } // namespace lldb_dap diff --git a/lldb/tools/lldb-dap/Handler/RequestHandler.cpp b/lldb/tools/lldb-dap/Handler/RequestHandler.cpp index 7a75cd93abc19..82c6e1b0071a9 100644 --- a/lldb/tools/lldb-dap/Handler/RequestHandler.cpp +++ b/lldb/tools/lldb-dap/Handler/RequestHandler.cpp @@ -162,7 +162,7 @@ RunInTerminal(DAP &dap, const protocol::LaunchRequestArguments &arguments) { dap.target.GetProcess().Continue(); // Now that the actual target is just starting (i.e. exec was just invoked), - // we return the debugger to its async state. + // we return the debugger to its sync state. scope_sync_mode.reset(); // If sending the notification failed, the launcher should be dead by now and @@ -238,35 +238,50 @@ llvm::Error BaseRequestHandler::LaunchProcess( launch_info.SetLaunchFlags(flags | lldb::eLaunchFlagDebug | lldb::eLaunchFlagStopAtEntry); - if (arguments.runInTerminal) { - if (llvm::Error err = RunInTerminal(dap, arguments)) - return err; - } else if (launchCommands.empty()) { - lldb::SBError error; - // Disable async events so the launch will be successful when we return from - // the launch call and the launch will happen synchronously + { + // Perform the launch in synchronous mode so that we don't have to worry + // about process state changes during the launch. ScopeSyncMode scope_sync_mode(dap.debugger); - dap.target.Launch(launch_info, error); - if (error.Fail()) - return llvm::make_error<DAPError>(error.GetCString()); - } else { - // Set the launch info so that run commands can access the configured - // launch details. - dap.target.SetLaunchInfo(launch_info); - if (llvm::Error err = dap.RunLaunchCommands(launchCommands)) - return err; - - // The custom commands might have created a new target so we should use the - // selected target after these commands are run. - dap.target = dap.debugger.GetSelectedTarget(); - // Make sure the process is launched and stopped at the entry point before - // proceeding as the launch commands are not run using the synchronous - // mode. - lldb::SBError error = dap.WaitForProcessToStop(arguments.timeout); - if (error.Fail()) - return llvm::make_error<DAPError>(error.GetCString()); + + if (arguments.runInTerminal) { + if (llvm::Error err = RunInTerminal(dap, arguments)) + return err; + } else if (launchCommands.empty()) { + lldb::SBError error; + dap.target.Launch(launch_info, error); + if (error.Fail()) + return llvm::make_error<DAPError>(error.GetCString()); + } else { + // Set the launch info so that run commands can access the configured + // launch details. + dap.target.SetLaunchInfo(launch_info); + if (llvm::Error err = dap.RunLaunchCommands(launchCommands)) + return err; + + // The custom commands might have created a new target so we should use + // the selected target after these commands are run. + dap.target = dap.debugger.GetSelectedTarget(); + } } + // Make sure the process is launched and stopped at the entry point before + // proceeding. + lldb::SBError error = dap.WaitForProcessToStop(arguments.timeout); + if (error.Fail()) + return llvm::make_error<DAPError>(error.GetCString()); + + // Clients can request a baseline of currently existing threads after + // we acknowledge the configurationDone request. + // Client requests the baseline of currently existing threads after + // a successful or attach by sending a 'threads' request + // right after receiving the configurationDone response. + // Obtain the list of threads before we resume the process + dap.initial_thread_list = + GetThreads(dap.target.GetProcess(), dap.thread_format); + + if (!dap.stop_at_entry) + dap.target.GetProcess().Continue(); + return llvm::Error::success(); } diff --git a/lldb/tools/lldb-dap/Handler/RequestHandler.h b/lldb/tools/lldb-dap/Handler/RequestHandler.h index fa3d76ed4a125..dec35c5dce1e5 100644 --- a/lldb/tools/lldb-dap/Handler/RequestHandler.h +++ b/lldb/tools/lldb-dap/Handler/RequestHandler.h @@ -282,6 +282,7 @@ class InitializeRequestHandler static llvm::StringLiteral GetCommand() { return "initialize"; } llvm::Expected<protocol::InitializeResponseBody> Run(const protocol::InitializeRequestArguments &args) const override; + void PostRun() const override; }; class LaunchRequestHandler _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
