Re: [PATCH 2/2] monitor/qmp: Stop processing requests when shutdown is requested

[Markus Armbruster]

Kevin Wolf <kwolf@redhat.com> writes:

> monitor_qmp_dispatcher_co() used to check whether shutdown is requested

"used to": until when?

> only when it would have to wait for new requests. If there were still
> some queued requests, it would try to execute all of them before
> shutting down.
>
> This can be surprising when the queued QMP commands take long or hang
> because Ctrl-C may not actually exit QEMU as soon as possible.
>
> Change monitor_qmp_dispatcher_co() so that it additionally checks
> whether shutdown is request before it gets a new request from the queue.
>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  monitor/qmp.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/monitor/qmp.c b/monitor/qmp.c
> index 43880fa623..2326bd7f9b 100644
> --- a/monitor/qmp.c
> +++ b/monitor/qmp.c
> @@ -227,6 +227,11 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
>           */
>          qatomic_mb_set(&qmp_dispatcher_co_busy, false);
>  
> +        /* On shutdown, don't take any more requests from the queue */
> +        if (qmp_dispatcher_co_shutdown) {
> +            return;
> +        }
> +
>          while (!(req_obj = monitor_qmp_requests_pop_any_with_lock())) {
>              /*
>               * No more requests to process.  Wait to be reentered from