[lldb-server/linux] Use waitpid(-1) to collect inferior events

[labath]

Summary

This is a follow-up to D116372, which had a rather unfortunate side
effect of making the processing of a single SIGCHLD quadratic in the
number of threads -- which does not matter for simple applications, but
can get really bad for applications with thousands of threads.

This patch fixes the problem by implementing the other possibility
mentioned in the first patch -- doing waitpid(-1) centrally and then
routing the events to the correct process instance. The "uncollected"
threads are held in the process factory class -- which I've renamed to
Manager for this purpose, as it now does more than creating processes.

[yinghuitan]

lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp

376–386

Maybe I misunderstood the purpose -- the code stores pid into m_unowned_threads for later collection if none of the process handle it. Instead, I thought we want to store into m_unowned_threads if at least one process did not handle it?

Can you add some comment to clarify the intention? Thanks.

547

Can you add back the original comment which I find useful? Thanks

// The process exited.  We're done monitoring.  Report to delegate.

lldb/source/Plugins/Process/Linux/NativeProcessLinux.h

70–72

I assume no lock is needed?

72

Add a comment for this field.

[labath]

lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp

376–386

The code is correct. Each event should be handled by exactly one process, but it may not happen immediately (if the process doesn't know about the thread). I've added some comments to clarify.

547

Yeah sure. It got lost because I changed the code a couple of times while working on it.

lldb/source/Plugins/Process/Linux/NativeProcessLinux.h

70–72

Yes. This is all single-threaded.

[labath]

Address review comments

[yinghuitan]

LGTM.

I have patched and verified this diff indeed fixed the performance issue in our internal service with 3000~4000 threads. Thanks for fixing it!

[fdeazeve]

@labath I believe this broke the lldb bots, because the declaration of some virtual functions had the const qualifier removed, but not the definition:

/Users/buildslave/jenkins/workspace/lldb-cmake@2/llvm-project/lldb/tools/lldb-server/lldb-gdbserver.cpp:79:36: error: non-virtual member function marked 'override' hides virtual member function
         MainLoop &mainloop) const override {
                                   ^
/Users/buildslave/jenkins/workspace/lldb-cmake@2/llvm-project/lldb/include/lldb/Host/common/NativeProcessProtocol.h:302:5: note: hidden overloaded virtual function 'lldb_private::NativeProcessProtocol::Manager::Launch' declared here: different number of parameters (2 vs 3)
    Launch(ProcessLaunchInfo &launch_info,
    ^
/Users/buildslave/jenkins/workspace/lldb-cmake@2/llvm-project/lldb/tools/lldb-server/lldb-gdbserver.cpp:84:36: error: non-virtual member function marked 'override' hides virtual member function
         MainLoop &mainloop) const override {
                                   ^
/Users/buildslave/jenkins/workspace/lldb-cmake@2/llvm-project/lldb/include/lldb/Host/common/NativeProcessProtocol.h:324:5: note: hidden overloaded virtual function 'lldb_private::NativeProcessProtocol::Manager::Attach' declared here: different number of parameters (2 vs 3)
    Attach(lldb::pid_t pid, NativeDelegate &native_delegate) = 0;
    ^
/Users/buildslave/jenkins/workspace/lldb-cmake@2/llvm-project/lldb/tools/lldb-server/lldb-gdbserver.cpp:434:24: error: variable type '(anonymous namespace)::NativeProcessManager' is an abstract class
  NativeProcessManager manager(mainloop);
                       ^
/Users/buildslave/jenkins/workspace/lldb-cmake@2/llvm-project/lldb/include/lldb/Host/common/NativeProcessProtocol.h:302:5: note: unimplemented pure virtual method 'Launch' in 'NativeProcessManager'
    Launch(ProcessLaunchInfo &launch_info,
    ^
/Users/buildslave/jenkins/workspace/lldb-cmake@2/llvm-project/lldb/include/lldb/Host/common/NativeProcessProtocol.h:324:5: note: unimplemented pure virtual method 'Attach' in 'NativeProcessManager'
    Attach(lldb::pid_t pid, NativeDelegate &native_delegate) = 0;

Could you have a look? https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/53015/console

[thakis]

Looks like this breaks building on Mac: http://45.33.8.238/macm1/57676/step_4.txt

Please take a look and revert for now if it takes a while to fix.

[fdeazeve]

Jonas fixed the build failures in c8522cadf7331bedd548ad5e2c6ef100c9166259

[labath]

Thanks Jonas.

lldb/include/lldb/Host/common/NativeProcessProtocol.h

public:
   };
 
   virtual Status GetLoadedModuleFileSpec(const char *module_path,
                                          FileSpec &file_spec) = 0;
 
   virtual Status GetFileLoadAddress(const llvm::StringRef &file_name,
                                     lldb::addr_t &load_addr) = 0;
 
-  /// Extension flag constants, returned by Factory::GetSupportedExtensions()
+  /// Extension flag constants, returned by Manager::GetSupportedExtensions()
   /// and passed to SetEnabledExtension()
   enum class Extension {
     multiprocess = (1u << 0),
     fork = (1u << 1),
     vfork = (1u << 2),
     pass_signals = (1u << 3),
     auxv = (1u << 4),
     libraries_svr4 = (1u << 5),
     memory_tagging = (1u << 6),
     savecore = (1u << 7),
     siginfo_read = (1u << 8),
 
     LLVM_MARK_AS_BITMASK_ENUM(siginfo_read)
   };
 
-  class Factory {
+  class Manager {
   public:
-    virtual ~Factory();
+    Manager(MainLoop &mainloop) : m_mainloop(mainloop) {}
+    Manager(const Manager &) = delete;
+    Manager &operator=(const Manager &) = delete;
+
+    virtual ~Manager();
+
     /// Launch a process for debugging.
     ///
     /// \param[in] launch_info
     ///     Information required to launch the process.
     ///
     /// \param[in] native_delegate
     ///     The delegate that will receive messages regarding the
     ///     inferior.  Must outlive the NativeProcessProtocol
     ///     instance.
     ///
     /// \param[in] mainloop
     ///     The mainloop instance with which the process can register
     ///     callbacks. Must outlive the NativeProcessProtocol
     ///     instance.
     ///
     /// \return
     ///     A NativeProcessProtocol shared pointer if the operation succeeded or
     ///     an error object if it failed.
     virtual llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Launch(ProcessLaunchInfo &launch_info, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const = 0;
+    Launch(ProcessLaunchInfo &launch_info,
+           NativeDelegate &native_delegate) = 0;
 
     /// Attach to an existing process.
     ///
     /// \param[in] pid
     ///     pid of the process locatable
     ///
     /// \param[in] native_delegate
     ///     The delegate that will receive messages regarding the
     ///     inferior.  Must outlive the NativeProcessProtocol
     ///     instance.
     ///
     /// \param[in] mainloop
     ///     The mainloop instance with which the process can register
     ///     callbacks. Must outlive the NativeProcessProtocol
     ///     instance.
     ///
     /// \return
     ///     A NativeProcessProtocol shared pointer if the operation succeeded or
     ///     an error object if it failed.
     virtual llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Attach(lldb::pid_t pid, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const = 0;
+    Attach(lldb::pid_t pid, NativeDelegate &native_delegate) = 0;
 
     /// Get the bitmask of extensions supported by this process plugin.
     ///
     /// \return
     ///     A NativeProcessProtocol::Extension bitmask.
     virtual Extension GetSupportedExtensions() const { return {}; }
+
+  protected:
+    MainLoop &m_mainloop;
   };
 
   /// Notify tracers that the target process will resume
   virtual void NotifyTracersProcessWillResume() {}
 
   /// Notify tracers that the target process just stopped
   virtual void NotifyTracersProcessDidStop() {}
 

lldb/source/Host/common/NativeProcessProtocol.cpp

uint32_t NativeProcessProtocol::GetStopID() const {
   std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
   return m_stop_id;
 }
 
 void NativeProcessProtocol::DoStopIDBumped(uint32_t /* newBumpId */) {
   // Default implementation does nothing.
 }
 
-NativeProcessProtocol::Factory::~Factory() = default;
+NativeProcessProtocol::Manager::~Manager() = default;

lldb/source/Plugins/Process/FreeBSD/NativeProcessFreeBSD.h

 ///
 /// Upon construction, this class prepares and launches an inferior process
 /// for debugging.
 ///
 /// Changes in the inferior process state are broadcasted.
 class NativeProcessFreeBSD : public NativeProcessELF,
                              private NativeProcessSoftwareSingleStep {
 public:
-  class Factory : public NativeProcessProtocol::Factory {
+  class Manager : public NativeProcessProtocol::Manager {
   public:
+    using NativeProcessProtocol::Manager::Manager;
+
     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Launch(ProcessLaunchInfo &launch_info, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const override;
+    Launch(ProcessLaunchInfo &launch_info,
+           NativeDelegate &native_delegate) override;
 
     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Attach(lldb::pid_t pid, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const override;
+    Attach(lldb::pid_t pid, NativeDelegate &native_delegate) override;
 
     Extension GetSupportedExtensions() const override;
   };
 
   // NativeProcessProtocol Interface
   Status Resume(const ResumeActionList &resume_actions) override;
 
   Status Halt() override;

lldb/source/Plugins/Process/FreeBSD/NativeProcessFreeBSD.cpp

static Status EnsureFDFlags(int fd, int flags) {
   }
 
   return error;
 }
 
 // Public Static Methods
 
 llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-NativeProcessFreeBSD::Factory::Launch(ProcessLaunchInfo &launch_info,
-                                      NativeDelegate &native_delegate,
-                                      MainLoop &mainloop) const {
+NativeProcessFreeBSD::Manager::Launch(ProcessLaunchInfo &launch_info,
+                                      NativeDelegate &native_delegate) {
   Log *log = GetLog(POSIXLog::Process);
 
   Status status;
   ::pid_t pid = ProcessLauncherPosixFork()
                     .LaunchProcess(launch_info, status)
                     .GetProcessId();
   LLDB_LOG(log, "pid = {0:x}", pid);
   if (status.Fail()) {
NativeProcessFreeBSD::Manager::Launch(ProcessLaunchInfo &launch_info,
   }
 
   // Set the architecture to the exe architecture.
   LLDB_LOG(log, "pid = {0:x}, detected architecture {1}", pid,
            Info.GetArchitecture().GetArchitectureName());
 
   std::unique_ptr<NativeProcessFreeBSD> process_up(new NativeProcessFreeBSD(
       pid, launch_info.GetPTY().ReleasePrimaryFileDescriptor(), native_delegate,
-      Info.GetArchitecture(), mainloop));
+      Info.GetArchitecture(), m_mainloop));
 
   status = process_up->SetupTrace();
   if (status.Fail())
     return status.ToError();
 
   for (const auto &thread : process_up->m_threads)
     static_cast<NativeThreadFreeBSD &>(*thread).SetStoppedBySignal(SIGSTOP);
   process_up->SetState(StateType::eStateStopped, false);
 
   return std::move(process_up);
 }
 
 llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-NativeProcessFreeBSD::Factory::Attach(
-    lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate,
-    MainLoop &mainloop) const {
+NativeProcessFreeBSD::Manager::Attach(
+    lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate) {
   Log *log = GetLog(POSIXLog::Process);
   LLDB_LOG(log, "pid = {0:x}", pid);
 
   // Retrieve the architecture for the running process.
   ProcessInstanceInfo Info;
   if (!Host::GetProcessInfo(pid, Info)) {
     return llvm::make_error<StringError>("Cannot get process architecture",
                                          llvm::inconvertibleErrorCode());
   }
 
   std::unique_ptr<NativeProcessFreeBSD> process_up(new NativeProcessFreeBSD(
-      pid, -1, native_delegate, Info.GetArchitecture(), mainloop));
+      pid, -1, native_delegate, Info.GetArchitecture(), m_mainloop));
 
   Status status = process_up->Attach();
   if (!status.Success())
     return status.ToError();
 
   return std::move(process_up);
 }
 
 NativeProcessFreeBSD::Extension
-NativeProcessFreeBSD::Factory::GetSupportedExtensions() const {
+NativeProcessFreeBSD::Manager::GetSupportedExtensions() const {
   return
 #if defined(PT_COREDUMP)
       Extension::savecore |
 #endif
       Extension::multiprocess | Extension::fork | Extension::vfork |
       Extension::pass_signals | Extension::auxv | Extension::libraries_svr4 |
       Extension::siginfo_read;
 }

lldb/source/Plugins/Process/Linux/NativeProcessLinux.h

 
 #include "lldb/Host/Debug.h"
 #include "lldb/Host/HostThread.h"
 #include "lldb/Host/linux/Support.h"
 #include "lldb/Target/MemoryRegionInfo.h"
 #include "lldb/Utility/ArchSpec.h"
 #include "lldb/Utility/FileSpec.h"
 #include "lldb/lldb-types.h"
+#include "llvm/ADT/SmallPtrSet.h"
 
 #include "IntelPTCollector.h"
 #include "NativeThreadLinux.h"
 #include "Plugins/Process/POSIX/NativeProcessELF.h"
 #include "Plugins/Process/Utility/NativeProcessSoftwareSingleStep.h"
 
 namespace lldb_private {
 class Status;
 class Scalar;
 
 namespace process_linux {
 /// \class NativeProcessLinux
 /// Manages communication with the inferior (debugee) process.
 ///
 /// Upon construction, this class prepares and launches an inferior process
 /// for debugging.
 ///
 /// Changes in the inferior process state are broadcasted.
 class NativeProcessLinux : public NativeProcessELF,
                            private NativeProcessSoftwareSingleStep {
 public:
-  class Factory : public NativeProcessProtocol::Factory {
+  class Manager : public NativeProcessProtocol::Manager {
   public:
+    Manager(MainLoop &mainloop);
+
     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Launch(ProcessLaunchInfo &launch_info, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const override;
+    Launch(ProcessLaunchInfo &launch_info,
+           NativeDelegate &native_delegate) override;
 
     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Attach(lldb::pid_t pid, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const override;
+    Attach(lldb::pid_t pid, NativeDelegate &native_delegate) override;
 
     Extension GetSupportedExtensions() const override;
+
+    void AddProcess(NativeProcessLinux &process) {
+      m_processes.insert(&process);
+    }
+
+    void RemoveProcess(NativeProcessLinux &process) {
+      m_processes.erase(&process);
+    }
+
+    // Collect an event for the given tid, waiting for it if necessary.
+    void CollectThread(::pid_t tid);
+
+  private:
+    MainLoop::SignalHandleUP m_sigchld_handle;
+
+    llvm::SmallPtrSet<NativeProcessLinux *, 2> m_processes;
+
+    // Threads (events) which haven't been claimed by any process.
+    llvm::DenseSet<::pid_t> m_unowned_threads;
+
+    void SigchldHandler();
   };
 
   // NativeProcessProtocol Interface
+
+  ~NativeProcessLinux() override { m_manager.RemoveProcess(*this); }
+
   Status Resume(const ResumeActionList &resume_actions) override;
 
   Status Halt() override;
 
   Status Detach() override;
 
   Status Signal(int signo) override;
 

 
 protected:
   llvm::Expected<llvm::ArrayRef<uint8_t>>
   GetSoftwareBreakpointTrapOpcode(size_t size_hint) override;
 
   llvm::Expected<uint64_t> Syscall(llvm::ArrayRef<uint64_t> args);
 
 private:
-  MainLoop::SignalHandleUP m_sigchld_handle;
+  Manager &m_manager;
   ArchSpec m_arch;
-  MainLoop& m_main_loop;
 
   LazyBool m_supports_mem_region = eLazyBoolCalculate;
   std::vector<std::pair<MemoryRegionInfo, FileSpec>> m_mem_region_cache;
 
   lldb::tid_t m_pending_notification_tid = LLDB_INVALID_THREAD_ID;
 
   /// Inferior memory (allocated by us) and its size.
   llvm::DenseMap<lldb::addr_t, lldb::addr_t> m_allocated_memory;
 
   // Private Instance Methods
   NativeProcessLinux(::pid_t pid, int terminal_fd, NativeDelegate &delegate,
-                     const ArchSpec &arch, MainLoop &mainloop,
+                     const ArchSpec &arch, Manager &manager,
                      llvm::ArrayRef<::pid_t> tids);
 
   // Returns a list of process threads that we have attached to.
   static llvm::Expected<std::vector<::pid_t>> Attach(::pid_t pid);
 
   static Status SetDefaultPtraceOpts(const lldb::pid_t);
 
-  void MonitorCallback(NativeThreadLinux &thread, WaitStatus status);
+  bool TryHandleWaitStatus(lldb::pid_t pid, WaitStatus status);
 
-  void WaitForCloneNotification(::pid_t pid);
+  void MonitorCallback(NativeThreadLinux &thread, WaitStatus status);
 
   void MonitorSIGTRAP(const siginfo_t &info, NativeThreadLinux &thread);
 
   void MonitorTrace(NativeThreadLinux &thread);
 
   void MonitorBreakpoint(NativeThreadLinux &thread);
 
   void MonitorWatchpoint(NativeThreadLinux &thread, uint32_t wp_index);

lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp

return llvm::createStringError(
         "For more information, see: "
         "https://www.kernel.org/doc/Documentation/security/Yama.txt.");
   case 0:
   default:
     return original_error;
   }
 }
 
-// Public Static Methods
+NativeProcessLinux::Manager::Manager(MainLoop &mainloop)
+    : NativeProcessProtocol::Manager(mainloop) {
+  Status status;
+  m_sigchld_handle = mainloop.RegisterSignal(
+      SIGCHLD, [this](MainLoopBase &) { SigchldHandler(); }, status);
+  assert(m_sigchld_handle && status.Success());
+}
 
 llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-NativeProcessLinux::Factory::Launch(ProcessLaunchInfo &launch_info,
-                                    NativeDelegate &native_delegate,
-                                    MainLoop &mainloop) const {
+NativeProcessLinux::Manager::Launch(ProcessLaunchInfo &launch_info,
+                                    NativeDelegate &native_delegate) {
   Log *log = GetLog(POSIXLog::Process);
 
   MaybeLogLaunchInfo(launch_info);
 
   Status status;
   ::pid_t pid = ProcessLauncherPosixFork()
                     .LaunchProcess(launch_info, status)
                     .GetProcessId();
NativeProcessLinux::Manager::Launch(ProcessLaunchInfo &launch_info,
 
   llvm::Expected<ArchSpec> arch_or =
       NativeRegisterContextLinux::DetermineArchitecture(pid);
   if (!arch_or)
     return arch_or.takeError();
 
   return std::unique_ptr<NativeProcessLinux>(new NativeProcessLinux(
       pid, launch_info.GetPTY().ReleasePrimaryFileDescriptor(), native_delegate,
-      *arch_or, mainloop, {pid}));
+      *arch_or, *this, {pid}));
 }
 
 llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-NativeProcessLinux::Factory::Attach(
-    lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate,
-    MainLoop &mainloop) const {
+NativeProcessLinux::Manager::Attach(
+    lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate) {
   Log *log = GetLog(POSIXLog::Process);
   LLDB_LOG(log, "pid = {0:x}", pid);
 
   auto tids_or = NativeProcessLinux::Attach(pid);
   if (!tids_or)
     return tids_or.takeError();
   ArrayRef<::pid_t> tids = *tids_or;
   llvm::Expected<ArchSpec> arch_or =
       NativeRegisterContextLinux::DetermineArchitecture(tids[0]);
   if (!arch_or)
     return arch_or.takeError();
 
-  return std::unique_ptr<NativeProcessLinux>(new NativeProcessLinux(
-      pid, -1, native_delegate, *arch_or, mainloop, tids));
+  return std::unique_ptr<NativeProcessLinux>(
+      new NativeProcessLinux(pid, -1, native_delegate, *arch_or, *this, tids));
 }
 
 NativeProcessLinux::Extension
-NativeProcessLinux::Factory::GetSupportedExtensions() const {
+NativeProcessLinux::Manager::GetSupportedExtensions() const {
   NativeProcessLinux::Extension supported =
       Extension::multiprocess | Extension::fork | Extension::vfork |
       Extension::pass_signals | Extension::auxv | Extension::libraries_svr4 |
       Extension::siginfo_read;
 
 #ifdef __aarch64__
   // At this point we do not have a process so read auxv directly.
   if ((getauxval(AT_HWCAP2) & HWCAP2_MTE))
     supported |= Extension::memory_tagging;
 #endif
 
   return supported;
 }
 
+static std::optional<std::pair<lldb::pid_t, WaitStatus>> WaitPid() {
+  Log *log = GetLog(POSIXLog::Process);
+
+  int status;
+  ::pid_t wait_pid = llvm::sys::RetryAfterSignal(
+      -1, ::waitpid, -1, &status, __WALL | __WNOTHREAD | WNOHANG);
+
+  if (wait_pid == 0)
+    return std::nullopt;
+
+  if (wait_pid == -1) {
+    Status error(errno, eErrorTypePOSIX);
+    LLDB_LOG(log, "waitpid(-1, &status, _) failed: {1}", error);
+    return std::nullopt;
+  }
+
+  WaitStatus wait_status = WaitStatus::Decode(status);
+
+  LLDB_LOG(log, "waitpid(-1, &status, _) = {0}, status = {1}", wait_pid,
+           wait_status);
+  return std::make_pair(wait_pid, wait_status);
+}
+
+void NativeProcessLinux::Manager::SigchldHandler() {
+  Log *log = GetLog(POSIXLog::Process);
+  while (true) {
+    auto wait_result = WaitPid();
+    if (!wait_result)
+      return;
+    lldb::pid_t pid = wait_result->first;
+    WaitStatus status = wait_result->second;
+
+    // Ask each process whether it wants to handle the event. Each event should
+    // be handled by exactly one process, but thread creation events require
+    // special handling.
+    // Thread creation consists of two events (one on the parent and one on the
+    // child thread) and they can arrive in any order nondeterministically. The
+    // parent event carries the information about the child thread, but not
+    // vice-versa. This means that if the child event arrives first, it may not
+    // be handled by any process (because it doesn't know the thread belongs to
+    // it).
+    bool handled = llvm::any_of(m_processes, [&](NativeProcessLinux *process) {
+      return process->TryHandleWaitStatus(pid, status);
+    });
+    if (!handled) {
+      if (status.type == WaitStatus::Stop && status.status == SIGSTOP) {
+        // Store the thread creation event for later collection.
+        m_unowned_threads.insert(pid);
+      } else {
+        LLDB_LOG(log, "Ignoring waitpid event {0} for pid {1}", status, pid);
+      }
+    }
+  }
+}
+
+void NativeProcessLinux::Manager::CollectThread(::pid_t tid) {
+  Log *log = GetLog(POSIXLog::Process);
+
+  if (m_unowned_threads.erase(tid))
+    return; // We've encountered this thread already.
+
+  // The TID is not tracked yet, let's wait for it to appear.
+  int status = -1;
+  LLDB_LOG(log,
+           "received clone event for tid {0}. tid not tracked yet, "
+           "waiting for it to appear...",
+           tid);
+  ::pid_t wait_pid =
+      llvm::sys::RetryAfterSignal(-1, ::waitpid, tid, &status, __WALL);
+
+  // It's theoretically possible to get other events if the entire process was
+  // SIGKILLed before we got a chance to check this. In that case, we'll just
+  // clean everything up when we get the process exit event.
+
+  LLDB_LOG(log,
+           "waitpid({0}, &status, __WALL) => {1} (errno: {2}, status = {3})",
+           tid, wait_pid, errno, WaitStatus::Decode(status));
+}
+
 // Public Instance Methods
 
 NativeProcessLinux::NativeProcessLinux(::pid_t pid, int terminal_fd,
                                        NativeDelegate &delegate,
-                                       const ArchSpec &arch, MainLoop &mainloop,
+                                       const ArchSpec &arch, Manager &manager,
                                        llvm::ArrayRef<::pid_t> tids)
-    : NativeProcessELF(pid, terminal_fd, delegate), m_arch(arch),
-      m_main_loop(mainloop), m_intel_pt_collector(*this) {
+    : NativeProcessELF(pid, terminal_fd, delegate), m_manager(manager),
+      m_arch(arch), m_intel_pt_collector(*this) {
+  manager.AddProcess(*this);
   if (m_terminal_fd != -1) {
     Status status = EnsureFDFlags(m_terminal_fd, O_NONBLOCK);
     assert(status.Success());
   }
 
-  Status status;
-  m_sigchld_handle = mainloop.RegisterSignal(
-      SIGCHLD, [this](MainLoopBase &) { SigchldHandler(); }, status);
-  assert(m_sigchld_handle && status.Success());
-
   for (const auto &tid : tids) {
     NativeThreadLinux &thread = AddThread(tid, /*resume*/ false);
     ThreadWasCreated(thread);
   }
 
   // Let our process instance know the thread has stopped.
   SetCurrentThreadID(tids[0]);
   SetState(StateType::eStateStopped, false);
-
-  // Proccess any signals we received before installing our handler
-  SigchldHandler();
 }
 
 llvm::Expected<std::vector<::pid_t>> NativeProcessLinux::Attach(::pid_t pid) {
   Log *log = GetLog(POSIXLog::Process);
 
   Status status;
   // Use a map to keep track of the threads which we have attached/need to
   // attach.
Status NativeProcessLinux::SetDefaultPtraceOpts(lldb::pid_t pid) {
 
   // Have the tracer trace vfork-done in order to restore breakpoints after
   // the child finishes sharing memory.
   ptrace_opts |= PTRACE_O_TRACEVFORKDONE;
 
   return PtraceWrapper(PTRACE_SETOPTIONS, pid, nullptr, (void *)ptrace_opts);
 }
 
-// Handles all waitpid events from the inferior process.
+bool NativeProcessLinux::TryHandleWaitStatus(lldb::pid_t pid,
+                                             WaitStatus status) {
+  if (pid == GetID() &&
+      (status.type == WaitStatus::Exit || status.type == WaitStatus::Signal)) {
+    // The process exited.  We're done monitoring.  Report to delegate.
+    SetExitStatus(status, true);
+    return true;
+  }
+  if (NativeThreadLinux *thread = GetThreadByID(pid)) {
+    MonitorCallback(*thread, status);
+    return true;
+  }
+  return false;
+}
+
 void NativeProcessLinux::MonitorCallback(NativeThreadLinux &thread,
                                          WaitStatus status) {
   Log *log = GetLog(LLDBLog::Process);
 
   // Certain activities differ based on whether the pid is the tid of the main
   // thread.
   const bool is_main_thread = (thread.GetID() == GetID());
 
if (info_err.GetError() == EINVAL) {
       LLDB_LOG(log,
                "GetSignalInfo({0}) failed: {1}, status = {2}, main_thread = "
                "{3}. Expecting WIFEXITED soon.",
                thread.GetID(), info_err, status, is_main_thread);
     }
   }
 }
 
-void NativeProcessLinux::WaitForCloneNotification(::pid_t pid) {
-  Log *log = GetLog(POSIXLog::Process);
-
-  // The PID is not tracked yet, let's wait for it to appear.
-  int status = -1;
-  LLDB_LOG(log,
-           "received clone event for pid {0}. pid not tracked yet, "
-           "waiting for it to appear...",
-           pid);
-  ::pid_t wait_pid =
-      llvm::sys::RetryAfterSignal(-1, ::waitpid, pid, &status, __WALL);
-
-  // It's theoretically possible to get other events if the entire process was
-  // SIGKILLed before we got a chance to check this. In that case, we'll just
-  // clean everything up when we get the process exit event.
-
-  LLDB_LOG(log,
-           "waitpid({0}, &status, __WALL) => {1} (errno: {2}, status = {3})",
-           pid, wait_pid, errno, WaitStatus::Decode(status));
-}
-
 void NativeProcessLinux::MonitorSIGTRAP(const siginfo_t &info,
                                         NativeThreadLinux &thread) {
   Log *log = GetLog(POSIXLog::Process);
   const bool is_main_thread = (thread.GetID() == GetID());
 
   assert(info.si_signo == SIGTRAP && "Unexpected child signal!");
 
   switch (info.si_code) {

 }
 
 bool NativeProcessLinux::MonitorClone(NativeThreadLinux &parent,
                                       lldb::pid_t child_pid, int event) {
   Log *log = GetLog(POSIXLog::Process);
   LLDB_LOG(log, "parent_tid={0}, child_pid={1}, event={2}", parent.GetID(),
            child_pid, event);
 
-  WaitForCloneNotification(child_pid);
+  m_manager.CollectThread(child_pid);
 
   switch (event) {
   case PTRACE_EVENT_CLONE: {
     // PTRACE_EVENT_CLONE can either mean a new thread or a new process.
     // Try to grab the new process' PGID to figure out which one it is.
     // If PGID is the same as the PID, then it's a new process.  Otherwise,
     // it's a thread.
     auto tgid_ret = getPIDForTID(child_pid);
case PTRACE_EVENT_CLONE: {
     }
   }
     [[fallthrough]];
   case PTRACE_EVENT_FORK:
   case PTRACE_EVENT_VFORK: {
     bool is_vfork = event == PTRACE_EVENT_VFORK;
     std::unique_ptr<NativeProcessLinux> child_process{new NativeProcessLinux(
         static_cast<::pid_t>(child_pid), m_terminal_fd, m_delegate, m_arch,
-        m_main_loop, {static_cast<::pid_t>(child_pid)})};
+        m_manager, {static_cast<::pid_t>(child_pid)})};
     if (!is_vfork)
       child_process->m_software_breakpoints = m_software_breakpoints;
 
     Extension expected_ext = is_vfork ? Extension::vfork : Extension::fork;
     if (bool(m_enabled_extensions & expected_ext)) {
       m_delegate.NewSubprocess(this, std::move(child_process));
       // NB: non-vfork clone() is reported as fork
       parent.SetStoppedByFork(is_vfork, child_pid);
if (kill(GetID(), SIGSTOP) != 0)
     error.SetErrorToErrno();
 
   return error;
 }
 
 Status NativeProcessLinux::Detach() {
   Status error;
 
-  // Stop monitoring the inferior.
-  m_sigchld_handle.reset();
-
   // Tell ptrace to detach from the process.
   if (GetID() == LLDB_INVALID_PROCESS_ID)
     return error;
 
   for (const auto &thread : m_threads) {
     Status e = Detach(thread->GetID());
     if (e.Fail())
       error =
void NativeProcessLinux::ThreadWasCreated(NativeThreadLinux &thread) {
   if (m_pending_notification_tid != LLDB_INVALID_THREAD_ID &&
       StateIsRunningState(thread.GetState())) {
     // We will need to wait for this new thread to stop as well before firing
     // the notification.
     thread.RequestStop();
   }
 }
 
-static std::optional<WaitStatus> HandlePid(::pid_t pid) {
-  Log *log = GetLog(POSIXLog::Process);
-
-  int status;
-  ::pid_t wait_pid = llvm::sys::RetryAfterSignal(
-      -1, ::waitpid, pid, &status, __WALL | __WNOTHREAD | WNOHANG);
-
-  if (wait_pid == 0)
-    return std::nullopt;
-
-  if (wait_pid == -1) {
-    Status error(errno, eErrorTypePOSIX);
-    LLDB_LOG(log, "waitpid({0}, &status, _) failed: {1}", pid,
-             error);
-    return std::nullopt;
-  }
-
-  assert(wait_pid == pid);
-
-  WaitStatus wait_status = WaitStatus::Decode(status);
-
-  LLDB_LOG(log, "waitpid({0})  got status = {1}", pid, wait_status);
-  return wait_status;
-}
-
-void NativeProcessLinux::SigchldHandler() {
-  Log *log = GetLog(POSIXLog::Process);
-
-  // Threads can appear or disappear as a result of event processing, so gather
-  // the events upfront.
-  llvm::DenseMap<lldb::tid_t, WaitStatus> tid_events;
-  bool checked_main_thread = false;
-  for (const auto &thread_up : m_threads) {
-    if (thread_up->GetID() == GetID())
-      checked_main_thread = true;
-
-    if (std::optional<WaitStatus> status = HandlePid(thread_up->GetID()))
-      tid_events.try_emplace(thread_up->GetID(), *status);
-  }
-  // Check the main thread even when we're not tracking it as process exit
-  // events are reported that way.
-  if (!checked_main_thread) {
-    if (std::optional<WaitStatus> status = HandlePid(GetID()))
-      tid_events.try_emplace(GetID(), *status);
-  }
-
-  for (auto &KV : tid_events) {
-    LLDB_LOG(log, "processing {0}({1}) ...", KV.first, KV.second);
-    if (KV.first == GetID() && (KV.second.type == WaitStatus::Exit ||
-                                KV.second.type == WaitStatus::Signal)) {
-
-      // The process exited.  We're done monitoring.  Report to delegate.
-      SetExitStatus(KV.second, true);
-      return;
-    }
-    NativeThreadLinux *thread = GetThreadByID(KV.first);
-    assert(thread && "Why did this thread disappear?");
-    MonitorCallback(*thread, KV.second);
-  }
-}
-
 // Wrapper for ptrace to catch errors and log calls. Note that ptrace sets
 // errno on error because -1 can be a valid result (i.e. for PTRACE_PEEK*)
 Status NativeProcessLinux::PtraceWrapper(int req, lldb::pid_t pid, void *addr,
                                          void *data, size_t data_size,
                                          long *result) {
   Status error;
   long int ret;
 

lldb/source/Plugins/Process/NetBSD/NativeProcessNetBSD.h

 /// Manages communication with the inferior (debugee) process.
 ///
 /// Upon construction, this class prepares and launches an inferior process
 /// for debugging.
 ///
 /// Changes in the inferior process state are broadcasted.
 class NativeProcessNetBSD : public NativeProcessELF {
 public:
-  class Factory : public NativeProcessProtocol::Factory {
+  class Manager : public NativeProcessProtocol::Manager {
   public:
+    using NativeProcessProtocol::Manager::Manager;
+
     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Launch(ProcessLaunchInfo &launch_info, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const override;
+    Launch(ProcessLaunchInfo &launch_info,
+           NativeDelegate &native_delegate) override;
 
     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Attach(lldb::pid_t pid, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const override;
+    Attach(lldb::pid_t pid, NativeDelegate &native_delegate) override;
 
     Extension GetSupportedExtensions() const override;
   };
 
   // NativeProcessProtocol Interface
   Status Resume(const ResumeActionList &resume_actions) override;
 
   Status Halt() override;

lldb/source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp

static Status EnsureFDFlags(int fd, int flags) {
   }
 
   return error;
 }
 
 // Public Static Methods
 
 llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-NativeProcessNetBSD::Factory::Launch(ProcessLaunchInfo &launch_info,
-                                     NativeDelegate &native_delegate,
-                                     MainLoop &mainloop) const {
+NativeProcessNetBSD::Manager::Launch(ProcessLaunchInfo &launch_info,
+                                     NativeDelegate &native_delegate) {
   Log *log = GetLog(POSIXLog::Process);
 
   Status status;
   ::pid_t pid = ProcessLauncherPosixFork()
                     .LaunchProcess(launch_info, status)
                     .GetProcessId();
   LLDB_LOG(log, "pid = {0:x}", pid);
   if (status.Fail()) {
NativeProcessNetBSD::Manager::Launch(ProcessLaunchInfo &launch_info,
   }
 
   // Set the architecture to the exe architecture.
   LLDB_LOG(log, "pid = {0:x}, detected architecture {1}", pid,
            Info.GetArchitecture().GetArchitectureName());
 
   std::unique_ptr<NativeProcessNetBSD> process_up(new NativeProcessNetBSD(
       pid, launch_info.GetPTY().ReleasePrimaryFileDescriptor(), native_delegate,
-      Info.GetArchitecture(), mainloop));
+      Info.GetArchitecture(), m_mainloop));
 
   status = process_up->SetupTrace();
   if (status.Fail())
     return status.ToError();
 
   for (const auto &thread : process_up->m_threads)
     static_cast<NativeThreadNetBSD &>(*thread).SetStoppedBySignal(SIGSTOP);
   process_up->SetState(StateType::eStateStopped, false);
 
   return std::move(process_up);
 }
 
 llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-NativeProcessNetBSD::Factory::Attach(
-    lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate,
-    MainLoop &mainloop) const {
+NativeProcessNetBSD::Manager::Attach(
+    lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate) {
   Log *log = GetLog(POSIXLog::Process);
   LLDB_LOG(log, "pid = {0:x}", pid);
 
   // Retrieve the architecture for the running process.
   ProcessInstanceInfo Info;
   if (!Host::GetProcessInfo(pid, Info)) {
     return llvm::make_error<StringError>("Cannot get process architecture",
                                          llvm::inconvertibleErrorCode());
   }
 
   std::unique_ptr<NativeProcessNetBSD> process_up(new NativeProcessNetBSD(
-      pid, -1, native_delegate, Info.GetArchitecture(), mainloop));
+      pid, -1, native_delegate, Info.GetArchitecture(), m_mainloop));
 
   Status status = process_up->Attach();
   if (!status.Success())
     return status.ToError();
 
   return std::move(process_up);
 }
 
 NativeProcessNetBSD::Extension
-NativeProcessNetBSD::Factory::GetSupportedExtensions() const {
+NativeProcessNetBSD::Manager::GetSupportedExtensions() const {
   return Extension::multiprocess | Extension::fork | Extension::vfork |
          Extension::pass_signals | Extension::auxv | Extension::libraries_svr4 |
          Extension::savecore;
 }
 
 // Public Instance Methods
 
 NativeProcessNetBSD::NativeProcessNetBSD(::pid_t pid, int terminal_fd,

lldb/source/Plugins/Process/Windows/Common/NativeProcessWindows.h

 
 //------------------------------------------------------------------
 // NativeProcessWindows
 //------------------------------------------------------------------
 class NativeProcessWindows : public NativeProcessProtocol,
                              public ProcessDebugger {
 
 public:
-  class Factory : public NativeProcessProtocol::Factory {
+  class Manager : public NativeProcessProtocol::Manager {
   public:
+    using NativeProcessProtocol::Manager::Manager;
+
     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Launch(ProcessLaunchInfo &launch_info, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const override;
+    Launch(ProcessLaunchInfo &launch_info,
+           NativeDelegate &native_delegate) override;
 
     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-    Attach(lldb::pid_t pid, NativeDelegate &native_delegate,
-           MainLoop &mainloop) const override;
+    Attach(lldb::pid_t pid, NativeDelegate &native_delegate) override;
   };
 
   Status Resume(const ResumeActionList &resume_actions) override;
 
   Status Halt() override;
 
   Status Detach() override;
 

lldb/source/Plugins/Process/Windows/Common/NativeProcessWindows.cpp

if (!initial_stop) {
                record.GetExceptionAddress());
 
       // We are required to report the reason for the first stop after
       // launching or being attached.
       if (NativeThreadWindows *thread = GetThreadByID(record.GetThreadID()))
         SetStopReasonForThread(*thread, StopReason::eStopReasonBreakpoint);
 
       // Do not notify the native delegate (e.g. llgs) since at this moment
-      // the program hasn't returned from Factory::Launch() and the delegate
+      // the program hasn't returned from Manager::Launch() and the delegate
       // might not have an valid native process to operate on.
       SetState(eStateStopped, false);
 
       // Hit the initial stop. Continue the application.
       return ExceptionResult::BreakInDebugger;
     }
 
     [[fallthrough]];

 }
 
 void NativeProcessWindows::OnUnloadDll(lldb::addr_t module_addr) {
   if (!m_loaded_modules.empty())
     m_loaded_modules.clear();
 }
 
 llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-NativeProcessWindows::Factory::Launch(
+NativeProcessWindows::Manager::Launch(
     ProcessLaunchInfo &launch_info,
-    NativeProcessProtocol::NativeDelegate &native_delegate,
-    MainLoop &mainloop) const {
+    NativeProcessProtocol::NativeDelegate &native_delegate) {
   Error E = Error::success();
   auto process_up = std::unique_ptr<NativeProcessWindows>(
       new NativeProcessWindows(launch_info, native_delegate, E));
   if (E)
     return std::move(E);
   return std::move(process_up);
 }
 
 llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
-NativeProcessWindows::Factory::Attach(
-    lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate,
-    MainLoop &mainloop) const {
+NativeProcessWindows::Manager::Attach(
+    lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate) {
   Error E = Error::success();
   // Set pty primary fd invalid since it is not available.
   auto process_up = std::unique_ptr<NativeProcessWindows>(
       new NativeProcessWindows(pid, -1, native_delegate, E));
   if (E)
     return std::move(E);
   return std::move(process_up);
 }
 } // namespace lldb_private

lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h

 
 class GDBRemoteCommunicationServerLLGS
     : public GDBRemoteCommunicationServerCommon,
       public NativeProcessProtocol::NativeDelegate {
 public:
   // Constructors and Destructors
   GDBRemoteCommunicationServerLLGS(
       MainLoop &mainloop,
-      const NativeProcessProtocol::Factory &process_factory);
+      NativeProcessProtocol::Manager &process_manager);
 
   void SetLaunchInfo(const ProcessLaunchInfo &info);
 
   /// Launch a process with the current launch settings.
   ///
   /// This method supports running an lldb-gdbserver or similar
   /// server in a situation where the startup code has been provided
   /// with all the information for a child process to be launched.
struct DebuggedProcess {
 
     std::unique_ptr<NativeProcessProtocol> process_up;
     Flag flags;
   };
 
 protected:
   MainLoop &m_mainloop;
   MainLoop::ReadHandleUP m_network_handle_up;
-  const NativeProcessProtocol::Factory &m_process_factory;
+  NativeProcessProtocol::Manager &m_process_manager;
   lldb::tid_t m_current_tid = LLDB_INVALID_THREAD_ID;
   lldb::tid_t m_continue_tid = LLDB_INVALID_THREAD_ID;
   NativeProcessProtocol *m_current_process;
   NativeProcessProtocol *m_continue_process;
   std::recursive_mutex m_debugged_process_mutex;
   std::unordered_map<lldb::pid_t, DebuggedProcess> m_debugged_processes;
 
   Communication m_stdio_communication;

lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp

enum GDBRemoteServerError {
   eErrorNoProcess = eErrorFirst,
   eErrorResume,
   eErrorExitStatus
 };
 }
 
 // GDBRemoteCommunicationServerLLGS constructor
 GDBRemoteCommunicationServerLLGS::GDBRemoteCommunicationServerLLGS(
-    MainLoop &mainloop, const NativeProcessProtocol::Factory &process_factory)
+    MainLoop &mainloop, NativeProcessProtocol::Manager &process_manager)
     : GDBRemoteCommunicationServerCommon(), m_mainloop(mainloop),
-      m_process_factory(process_factory), m_current_process(nullptr),
+      m_process_manager(process_manager), m_current_process(nullptr),
       m_continue_process(nullptr), m_stdio_communication() {
   RegisterPacketHandlers();
 }
 
 void GDBRemoteCommunicationServerLLGS::RegisterPacketHandlers() {
   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_C,
                                 &GDBRemoteCommunicationServerLLGS::Handle_C);
   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_c,
if (llvm::Error Err = m_process_launch_info.SetUpPtyRedirection())
       return Status(std::move(Err));
 #endif
   }
 
   {
     std::lock_guard<std::recursive_mutex> guard(m_debugged_process_mutex);
     assert(m_debugged_processes.empty() && "lldb-server creating debugged "
                                            "process but one already exists");
-    auto process_or =
-        m_process_factory.Launch(m_process_launch_info, *this, m_mainloop);
+    auto process_or = m_process_manager.Launch(m_process_launch_info, *this);
     if (!process_or)
       return Status(process_or.takeError());
     m_continue_process = m_current_process = process_or->get();
     m_debugged_processes.emplace(
         m_current_process->GetID(),
         DebuggedProcess{std::move(*process_or), DebuggedProcess::Flag{}});
   }
 
Status GDBRemoteCommunicationServerLLGS::AttachToProcess(lldb::pid_t pid) {
   // else.
   if (!m_debugged_processes.empty())
     return Status("cannot attach to process %" PRIu64
                   " when another process with pid %" PRIu64
                   " is being debugged.",
                   pid, m_current_process->GetID());
 
   // Try to attach.
-  auto process_or = m_process_factory.Attach(pid, *this, m_mainloop);
+  auto process_or = m_process_manager.Attach(pid, *this);
   if (!process_or) {
     Status status(process_or.takeError());
     llvm::errs() << llvm::formatv("failed to attach to process {0}: {1}\n", pid,
                                   status);
     return status;
   }
   m_continue_process = m_current_process = process_or->get();
   m_debugged_processes.emplace(
ret.insert(ret.end(), {
                             "QThreadSuffixSupported+",
                             "QListThreadsInStopReply+",
                             "qXfer:features:read+",
                             "QNonStop+",
                         });
 
   // report server-only features
   using Extension = NativeProcessProtocol::Extension;
-  Extension plugin_features = m_process_factory.GetSupportedExtensions();
+  Extension plugin_features = m_process_manager.GetSupportedExtensions();
   if (bool(plugin_features & Extension::pass_signals))
     ret.push_back("QPassSignals+");
   if (bool(plugin_features & Extension::auxv))
     ret.push_back("qXfer:auxv:read+");
   if (bool(plugin_features & Extension::libraries_svr4))
     ret.push_back("qXfer:libraries-svr4:read+");
   if (bool(plugin_features & Extension::siginfo_read))
     ret.push_back("qXfer:siginfo:read+");
std::vector<std::string> GDBRemoteCommunicationServerLLGS::HandleFeatures(
   for (auto &x : m_debugged_processes)
     SetEnabledExtensions(*x.second.process_up);
   return ret;
 }
 
 void GDBRemoteCommunicationServerLLGS::SetEnabledExtensions(
     NativeProcessProtocol &process) {
   NativeProcessProtocol::Extension flags = m_extensions_supported;
-  assert(!bool(flags & ~m_process_factory.GetSupportedExtensions()));
+  assert(!bool(flags & ~m_process_manager.GetSupportedExtensions()));
   process.SetEnabledExtensions(flags);
 }
 
 GDBRemoteCommunication::PacketResult
 GDBRemoteCommunicationServerLLGS::SendContinueSuccessResponse() {
   if (m_non_stop)
     return SendOKResponse();
   StartSTDIOForwarding();

lldb/tools/lldb-server/lldb-gdbserver.cpp

 using namespace llvm;
 using namespace lldb;
 using namespace lldb_private;
 using namespace lldb_private::lldb_server;
 using namespace lldb_private::process_gdb_remote;
 
 namespace {
 #if defined(__linux__)
-typedef process_linux::NativeProcessLinux::Factory NativeProcessFactory;
+typedef process_linux::NativeProcessLinux::Manager NativeProcessManager;
 #elif defined(__FreeBSD__)
-typedef process_freebsd::NativeProcessFreeBSD::Factory NativeProcessFactory;
+typedef process_freebsd::NativeProcessFreeBSD::Manager NativeProcessManager;
 #elif defined(__NetBSD__)
-typedef process_netbsd::NativeProcessNetBSD::Factory NativeProcessFactory;
+typedef process_netbsd::NativeProcessNetBSD::Manager NativeProcessManager;
 #elif defined(_WIN32)
-typedef NativeProcessWindows::Factory NativeProcessFactory;
+typedef NativeProcessWindows::Manager NativeProcessManager;
 #else
 // Dummy implementation to make sure the code compiles
-class NativeProcessFactory : public NativeProcessProtocol::Factory {
+class NativeProcessManager : public NativeProcessProtocol::Manager {
 public:
   llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
   Launch(ProcessLaunchInfo &launch_info,
          NativeProcessProtocol::NativeDelegate &delegate,
          MainLoop &mainloop) const override {
     llvm_unreachable("Not implemented");
   }
   llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
if (opt::Arg *Arg = Args.getLastArg(OPT_REM)) {
     for (const char *Val : Arg->getValues())
       Inputs.push_back(Val);
   }
   if (Inputs.empty() && connection_fd == -1) {
     WithColor::error() << "no connection arguments\n" << HelpText;
     return 1;
   }
 
-  NativeProcessFactory factory;
-  GDBRemoteCommunicationServerLLGS gdb_server(mainloop, factory);
+  NativeProcessManager manager(mainloop);
+  GDBRemoteCommunicationServerLLGS gdb_server(mainloop, manager);
 
   llvm::StringRef host_and_port;
   if (!Inputs.empty()) {
     host_and_port = Inputs.front();
     Inputs.erase(Inputs.begin());
   }
 
   // Any arguments left over are for the program that we need to launch. If