Delay sync with the parent thread in ProcessLinux/ProcessMonitor.
This patch removes a potential race condition between a process monitor thread
and its parent waiting to interrogate the success/failure of the launch.
llvm-svn: 123803
diff --git a/lldb/source/Plugins/Process/Linux/ProcessMonitor.cpp b/lldb/source/Plugins/Process/Linux/ProcessMonitor.cpp
index 8fe7451..2c93638 100644
--- a/lldb/source/Plugins/Process/Linux/ProcessMonitor.cpp
+++ b/lldb/source/Plugins/Process/Linux/ProcessMonitor.cpp
@@ -607,7 +607,7 @@
if (!Launch(args))
return NULL;
- ServeOperation(args->m_monitor);
+ ServeOperation(args);
return NULL;
}
@@ -716,8 +716,6 @@
process.SendMessage(ProcessMessage::Trace(pid));
FINISH:
- // Sync with our parent thread now that the launch operation is complete.
- sem_post(&args->m_semaphore);
return args->m_error.Success();
}
@@ -819,15 +817,20 @@
}
void
-ProcessMonitor::ServeOperation(ProcessMonitor *monitor)
+ProcessMonitor::ServeOperation(LaunchArgs *args)
{
int status;
pollfd fdset;
+ ProcessMonitor *monitor = args->m_monitor;
fdset.fd = monitor->m_server_fd;
fdset.events = POLLIN | POLLPRI;
fdset.revents = 0;
+ // We are finised with the arguments and are ready to go. Sync with the
+ // parent thread and start serving operations on the inferior.
+ sem_post(&args->m_semaphore);
+
for (;;)
{
if ((status = poll(&fdset, 1, -1)) < 0)