| 文件 | 最后提交记录 | 最后更新时间 |
|---|---|---|
[LLDB][ProcessWindows] Set exit status on instance rather than going through all targets (#159308) When quitting LLDB on Windows while a process was still running, LLDB would take unusually long to exit. This was due to a temporary deadlock: The main thread was destroying the processes. In doing so, it iterated over the target list: https://github.com/llvm/llvm-project/blob/88c64f76ed2ca226da99b99f60d316b1519fc7d8/lldb/source/Core/Debugger.cpp#L1095-L1098 This locks the list for the whole iteration. Finalizing the process would eventually lead to DebuggerThread::StopDebugging, which terminates the process and waits for it to exit: https://github.com/llvm/llvm-project/blob/88c64f76ed2ca226da99b99f60d316b1519fc7d8/lldb/source/Plugins/Process/Windows/Common/DebuggerThread.cpp#L196 The debugger loop (on a separate thread) would see that the process exited and call [ProcessWindows::OnExitProcess](https://github.com/llvm/llvm-project/blob/88c64f76ed2ca226da99b99f60d316b1519fc7d8/lldb/source/Plugins/Process/Windows/Common/ProcessWindows.cpp#L656-L673). This calls the static function [Process::SetProcessExitStatus](https://github.com/llvm/llvm-project/blob/0a7a7d56fc882653335beba0d1f8ea9f26089c22/lldb/source/Target/Process.cpp#L1098-L1126). This tries to find the process by its ID from the debugger's target list. Doing so requires locking the list, so the debugger thread would then be stuck on https://github.com/llvm/llvm-project/blob/0a7a7d56fc882653335beba0d1f8ea9f26089c22/lldb/source/Target/TargetList.cpp#L403 After 5s, the main thread would give up waiting. So every exit where the process was still running would be delayed by about 5s. Since ProcessWindows would find itself when calling SetProcessExitStatus, we can call SetExitStatus directly. This can also make some tests run faster. For example, the DIA PDB tests previously took 15s to run on my PC (24 jobs) and now take 5s. For all shell tests, the difference isn't that big (only about 3s), because most don't run into this and the tests run in parallel. | 10 个月前 |