Re: [Qemu-devel] [PATCH v8 14/23] monitor: separate QMP parser and dispatcher

[Eric Blake]

On 03/09/2018 02:59 AM, Peter Xu wrote:
> Originally QMP goes through these steps:
>
>    JSON Parser --> QMP Dispatcher --> Respond
>        /|\    (2)                (3)     |
>     (1) |                               \|/ (4)
>         +---------  main thread  --------+
>
> This patch does this:
>
>    JSON Parser     QMP Dispatcher --> Respond
>        /|\ |           /|\       (4)     |
>         |  | (2)        | (3)            |  (5)
>     (1) |  +----->      |               \|/
>         +---------  main thread  <-------+
>
> So the parsing job and the dispatching job is isolated now.  It gives us
> a chance in following up patches to totally move the parser outside.

s/following/follow/

> The isolation is done using one QEMUBH. Only one dispatcher QEMUBH is
> used for all the monitors.
>
> Reviewed-by: Stefan Hajnoczi <address@hidden>
> Signed-off-by: Peter Xu <address@hidden>
> ---
>   monitor.c | 201 +++++++++++++++++++++++++++++++++++++++++++++++++++++++-------
>   1 file changed, 178 insertions(+), 23 deletions(-)

>   
>       if (trace_event_get_state_backends(TRACE_HANDLE_QMP_COMMAND)) {
>           QString *req_json = qobject_to_json(req);

More context conflicts.


> +/*
> + * Pop one QMP request from monitor queues, return NULL if not found.
> + * We are using round-robin fashion to pop the request, to avoid
> + * processing command only on a very busy monitor.  To achieve that,

s/command/commands/

> + * when we processed one request on specific monitor, we put that

s/processed/process/
s/on/on a/

> + * monitor to the end of mon_list queue.
> + */
> +static QMPRequest *monitor_qmp_requests_pop_one(void)
> +
> +    /*
> +     * If OOB is not enabled on current monitor, we'll emulate the old
> +     * behavior that we won't process current monitor any more until

s/current/the current/g

> +     * it is responded.  This helps make sure that as long as OOB is

/is responded/has responded/

> +     * not enabled, the server will never drop any command.
> +     */

Reviewed-by: Eric Blake <address@hidden>

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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