[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [RFC v4 15/27] monitor: let monitor_{suspend|resume} th
From: |
Dr. David Alan Gilbert |
Subject: |
Re: [Qemu-devel] [RFC v4 15/27] monitor: let monitor_{suspend|resume} thread safe |
Date: |
Thu, 23 Nov 2017 11:23:16 +0000 |
User-agent: |
Mutt/1.9.1 (2017-09-22) |
* Peter Xu (address@hidden) wrote:
> Monitor code now can be run in more than one thread. Let the suspend
> and resume code be thread safe.
>
> Reviewed-by: Fam Zheng <address@hidden>
> Signed-off-by: Peter Xu <address@hidden>
> ---
> monitor.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/monitor.c b/monitor.c
> index ec03f1b232..30f9cd80de 100644
> --- a/monitor.c
> +++ b/monitor.c
> @@ -4003,7 +4003,7 @@ int monitor_suspend(Monitor *mon)
> {
> if (!mon->rs)
> return -ENOTTY;
> - mon->suspend_cnt++;
> + atomic_inc(&mon->suspend_cnt);
> return 0;
> }
>
> @@ -4011,8 +4011,9 @@ void monitor_resume(Monitor *mon)
> {
> if (!mon->rs)
> return;
> - if (--mon->suspend_cnt == 0)
> + if (atomic_dec_fetch(&mon->suspend_cnt) == 0) {
> readline_show_prompt(mon->rs);
> + }
> }
>
> static QObject *get_qmp_greeting(void)
Do you also need to do an atomic_read() in monitor_can_read?
(I guess the code in monitor_event is ok because it's only the mux
path, but still it's probably better to use all atomic ops on
the suspend_cnt variable to be consistent).
Dave
> --
> 2.13.6
>
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK
- [Qemu-devel] [RFC v4 09/27] monitor: create monitor dedicate iothread, (continued)
[Qemu-devel] [RFC v4 11/27] qmp: introduce QMPCapability, Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 13/27] qmp: introduce some capability helpers, Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 12/27] qmp: negociate QMP capabilities, Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 14/27] monitor: introduce monitor_qmp_respond(), Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 15/27] monitor: let monitor_{suspend|resume} thread safe, Peter Xu, 2017/11/16
- Re: [Qemu-devel] [RFC v4 15/27] monitor: let monitor_{suspend|resume} thread safe,
Dr. David Alan Gilbert <=
[Qemu-devel] [RFC v4 16/27] monitor: separate QMP parser and dispatcher, Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 17/27] qmp: add new event "request-dropped", Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 18/27] monitor: send event when request queue full, Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 19/27] qapi: introduce new cmd option "allow-oob", Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 20/27] qmp: support out-of-band (oob) execution, Peter Xu, 2017/11/16
[Qemu-devel] [RFC v4 21/27] qmp: let migrate-incoming allow out-of-band, Peter Xu, 2017/11/16