[Lldb-commits] [lldb] b424b0b - [lldb/Target] Avoid race between Communication::Disconnect calls.

[Jonas Devlieghere via lldb-commits]

Author: Jonas Devlieghere
Date: 2020-04-22T16:56:42-07:00
New Revision: b424b0bf731d1fb338180553a86f912746f640ad

URL: https://github.com/llvm/llvm-project/commit/b424b0bf731d1fb338180553a86f912746f640ad
DIFF: https://github.com/llvm/llvm-project/commit/b424b0bf731d1fb338180553a86f912746f640ad.diff

LOG: [lldb/Target] Avoid race between Communication::Disconnect calls.

Avoid a race between the Disconnect call in `Communication::ReadThread`
and the one in `Process::ShouldBroadcastEvent` by reordering the calls
to Disconnect and StopReadThread in `Process::ShouldBroadcastEvent`.

In D77295 Pavel suggested that that might explain the broken pipe I was
seeing. Indeed, changing the order resolved the issue.

Added: 
    

Modified: 
    lldb/source/Target/Process.cpp

Removed: 
    


################################################################################
diff  --git a/lldb/source/Target/Process.cpp b/lldb/source/Target/Process.cpp
index 7797a4c60964..45dcfc489d81 100644
--- a/lldb/source/Target/Process.cpp
+++ b/lldb/source/Target/Process.cpp
@@ -3386,8 +3386,8 @@ bool Process::ShouldBroadcastEvent(Event *event_ptr) {
   case eStateExited:
   case eStateUnloaded:
     m_stdio_communication.SynchronizeWithReadThread();
-    m_stdio_communication.Disconnect();
     m_stdio_communication.StopReadThread();
+    m_stdio_communication.Disconnect();
     m_stdin_forward = false;
 
     LLVM_FALLTHROUGH;