Author: labath Date: Tue Oct 27 04:23:55 2015 New Revision: 251399 URL: http://llvm.org/viewvc/llvm-project?rev=251399&view=rev Log: Fix race condition in process resume
Summary: Gdb-remote's async thread sent out the eBroadcastBitRunPacketSent message *before* actually sending out the continue packet. Since it's this message the actually triggers the public state transition, it could happen (and it did happen in TestAttachResume, which does an "process interrupt" right after a continue) that we attempt to stop the inferior before it was actually started (which obviously did not end well). This fixes the problem by moving the broadcast after the packet was actually sent. Reviewers: clayborg Subscribers: lldb-commits Differential Revision: http://reviews.llvm.org/D14083 Modified: lldb/trunk/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp lldb/trunk/test/functionalities/attach_resume/TestAttachResume.py Modified: lldb/trunk/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp?rev=251399&r1=251398&r2=251399&view=diff ============================================================================== --- lldb/trunk/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp (original) +++ lldb/trunk/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp Tue Oct 27 04:23:55 2015 @@ -1049,7 +1049,6 @@ GDBRemoteCommunicationClient::SendContin Mutex::Locker locker(m_sequence_mutex); StateType state = eStateRunning; - BroadcastEvent(eBroadcastBitRunPacketSent, NULL); m_public_is_running.SetValue (true, eBroadcastNever); // Set the starting continue packet into "continue_packet". This packet // may change if we are interrupted and we continue after an async packet... @@ -1059,6 +1058,7 @@ GDBRemoteCommunicationClient::SendContin const auto sigint_signo = process->GetUnixSignals()->GetSignalNumberFromName("SIGINT"); bool got_async_packet = false; + bool broadcast_sent = false; while (state == eStateRunning) { @@ -1071,6 +1071,12 @@ GDBRemoteCommunicationClient::SendContin else m_interrupt_sent = false; + if (! broadcast_sent) + { + BroadcastEvent(eBroadcastBitRunPacketSent, NULL); + broadcast_sent = true; + } + m_private_is_running.SetValue (true, eBroadcastAlways); } Modified: lldb/trunk/test/functionalities/attach_resume/TestAttachResume.py URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/test/functionalities/attach_resume/TestAttachResume.py?rev=251399&r1=251398&r2=251399&view=diff ============================================================================== --- lldb/trunk/test/functionalities/attach_resume/TestAttachResume.py (original) +++ lldb/trunk/test/functionalities/attach_resume/TestAttachResume.py Tue Oct 27 04:23:55 2015 @@ -20,7 +20,6 @@ class AttachResumeTestCase(TestBase): @skipIfRemote @expectedFailureFreeBSD('llvm.org/pr19310') @expectedFailureWindows("llvm.org/pr24778") - @expectedFlakeyLinux('llvm.org/pr19310') def test_attach_continue_interrupt_detach(self): """Test attach/continue/interrupt/detach""" self.build() _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
