Unverified Commit 3bb1888a authored by copilot-swe-agent[bot]'s avatar copilot-swe-agent[bot] Committed by GitHub
Browse files

fix: Handle graceful exit when QEMU terminates in balloon monitor 

- Add _is_process_alive() helper to check if QEMU is still running
- Check QEMU process liveness before retrying QMP connection
- Exit cleanly from _qmp_reconnect when QEMU has exited
- Suppress noisy qemu.qmp library INFO messages (e.g. "end-of-file")
- Catch connection-related exceptions at top level for clean exit
parent 118d9a56

src/balloon.py

+29 −3
Original line number Diff line number Diff line
@@ -213,9 +213,20 @@ async def _get_host_qemu_guest_mem_rss(qmp: QMPClient, qemu_pid: int) -> Optiona 
# QMP helpers using qemu.qmp

# ==========================================================



async def qmp_wait_connected(sock_path: str, interval: int = 5) -> QMPClient:

    """Create and connect a QMPClient, retrying until successful."""

def _is_process_alive(pid: int) -> bool:

    """Check if a process with the given PID is still running."""

    try:

        os.kill(pid, 0)

        return True

    except (ProcessLookupError, OSError):

        return False





async def qmp_wait_connected(sock_path: str, interval: int = 5, qemu_pid: int = -1) -> QMPClient:

    """Create and connect a QMPClient, retrying until successful or QEMU exits."""

    while True:

        if qemu_pid > 0 and not _is_process_alive(qemu_pid):

            raise ConnectionError("QEMU process (pid %d) is no longer running" % qemu_pid)

        qmp = QMPClient("balloon-monitor")

        try:

            await qmp.connect(sock_path)
@@ -367,7 +378,7 @@ class BalloonMonitor: 
        )



    async def _qmp_connect(self) -> None:

        self.qmp = await qmp_wait_connected(self.args.qmp_sock, self.args.interval)

        self.qmp = await qmp_wait_connected(self.args.qmp_sock, self.args.interval, self.qemu_pid)

        self.event_task = asyncio.create_task(self._qmp_event_listener())

        self._record_balloon(await qmp_get_actual_balloon(self.qmp))
@@ -389,6 +400,10 @@ class BalloonMonitor: 
            log.debug("QMP event listener stopped: %s", e)



    async def _qmp_reconnect(self) -> None:

        if self.qemu_pid > 0 and not _is_process_alive(self.qemu_pid):

            log.info("QEMU process (pid %d) has exited, shutting down.", self.qemu_pid)

            self._stop.set()

            return

        if self.qmp:

            try:

                await self.qmp.disconnect()
@@ -759,6 +774,9 @@ def main() -> None: 
        datefmt="%Y-%m-%d %H:%M:%S",

    )



    # Suppress noisy qemu.qmp internal messages (e.g. "end-of-file") unless debug is requested

    logging.getLogger("qemu.qmp").setLevel(logging.WARNING)



    if args.debug is not None:

        targets = {t.strip() for t in args.debug.split(",")}

        if "all" in targets:
@@ -778,3 +796,11 @@ if __name__ == "__main__": 
    except KeyboardInterrupt:

        log.debug("Monitor stopped by user.")

        sys.exit(0)

    except (ConnectionError, BrokenPipeError, OSError) as e:

        log.info("Monitor exiting: %s", e)

        sys.exit(0)

    except SystemExit:

        raise

    except Exception as e:

        log.error("Monitor terminated unexpectedly: %s", e, exc_info=e)

        sys.exit(1)