Re: [Qemu-devel] [PATCH v4 1/5] net/announce: Allow optional list of interfaces

[Jason Wang]

On 2019/6/13 下午5:59, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <address@hidden>
>
> Allow the caller to restrict the set of interfaces that announces are
> sent on.  The default is still to send on all interfaces.
>
> e.g.
>
>    { "execute": "announce-self", "arguments": { "initial": 50, "max": 550, "rounds": 5, "step": 50, 
> "interfaces": ["vn2", "vn1"] } }
>
> This doesn't affect the behaviour of migraiton announcments.
>
> Note: There's still only one timer for the qmp command, so that
> performing an 'announce-self' on one list of interfaces followed
> by another 'announce-self' on another list will stop the announces
> on the existing set.
>
> Signed-off-by: Dr. David Alan Gilbert <address@hidden>
> ---
>   include/net/announce.h |  2 +-
>   net/announce.c         | 39 ++++++++++++++++++++++++++++++++-------
>   net/trace-events       |  2 +-
>   qapi/net.json          | 11 ++++++++---
>   4 files changed, 42 insertions(+), 12 deletions(-)
>
> diff --git a/include/net/announce.h b/include/net/announce.h
> index 04a035f679..773470428b 100644
> --- a/include/net/announce.h
> +++ b/include/net/announce.h
> @@ -22,7 +22,7 @@ struct AnnounceTimer {
>   /* Returns: update the timer to the next time point */
>   int64_t qemu_announce_timer_step(AnnounceTimer *timer);
>   
> -/* Delete the underlying timer */
> +/* Delete the underlying timer and other data */
>   void qemu_announce_timer_del(AnnounceTimer *timer);
>   
>   /*
> diff --git a/net/announce.c b/net/announce.c
> index 91e9a6e267..1ce42b571d 100644
> --- a/net/announce.c
> +++ b/net/announce.c
> @@ -38,6 +38,8 @@ void qemu_announce_timer_del(AnnounceTimer *timer)
>           timer_free(timer->tm);
>           timer->tm = NULL;
>       }
> +    qapi_free_strList(timer->params.interfaces);
> +    timer->params.interfaces = NULL;
>   }
>   
>   /*
> @@ -96,24 +98,47 @@ static int announce_self_create(uint8_t *buf,
>   
>   static void qemu_announce_self_iter(NICState *nic, void *opaque)
>   {
> +    AnnounceTimer *timer = opaque;
>       uint8_t buf[60];
>       int len;
> +    bool skip;
> +
> +    if (timer->params.has_interfaces) {
> +        strList *entry = timer->params.interfaces;
> +        /* Skip unless we find our name in the requested list */
> +        skip = true;
> +
> +        while (entry) {
> +            if (!strcmp(entry->value, nic->ncs->name)) {
> +                /* Found us */
> +                skip = false;
> +                break;
> +            }
> +            entry = entry->next;
> +        }
> +    } else {
> +        skip = false;
> +    }


I wonder whether or not it's better to filter the name on the caller.

Thanks


> +
> +    trace_qemu_announce_self_iter(nic->ncs->name,
> +                                  qemu_ether_ntoa(&nic->conf->macaddr), skip);
>   
> -    trace_qemu_announce_self_iter(qemu_ether_ntoa(&nic->conf->macaddr));
> -    len = announce_self_create(buf, nic->conf->macaddr.a);
> +    if (!skip) {
> +        len = announce_self_create(buf, nic->conf->macaddr.a);
>   
> -    qemu_send_packet_raw(qemu_get_queue(nic), buf, len);
> +        qemu_send_packet_raw(qemu_get_queue(nic), buf, len);
>   
> -    /* if the NIC provides it's own announcement support, use it as well */
> -    if (nic->ncs->info->announce) {
> -        nic->ncs->info->announce(nic->ncs);
> +        /* if the NIC provides it's own announcement support, use it as well */
> +        if (nic->ncs->info->announce) {
> +            nic->ncs->info->announce(nic->ncs);
> +        }
>       }
>   }
>   static void qemu_announce_self_once(void *opaque)
>   {
>       AnnounceTimer *timer = (AnnounceTimer *)opaque;
>   
> -    qemu_foreach_nic(qemu_announce_self_iter, NULL);
> +    qemu_foreach_nic(qemu_announce_self_iter, timer);
>   
>       if (--timer->round) {
>           qemu_announce_timer_step(timer);
> diff --git a/net/trace-events b/net/trace-events
> index a7937f3f3a..875ef2a0f3 100644
> --- a/net/trace-events
> +++ b/net/trace-events
> @@ -1,7 +1,7 @@
>   # See docs/devel/tracing.txt for syntax documentation.
>   
>   # announce.c
> -qemu_announce_self_iter(const char *mac) "%s"
> +qemu_announce_self_iter(const char *name, const char *mac, int skip) "%s:%s skip: 
> %d"
>   
>   # vhost-user.c
>   vhost_user_event(const char *chr, int event) "chr: %s got event: %d"
> diff --git a/qapi/net.json b/qapi/net.json
> index 5f7bff1637..6f2cd4f530 100644
> --- a/qapi/net.json
> +++ b/qapi/net.json
> @@ -699,6 +699,9 @@
>   #
>   # @step: Delay increase (in ms) after each self-announcement attempt
>   #
> +# @interfaces: An optional list of interface names, which restricts the
> +#        announcement to the listed interfaces. (Since 4.1)
> +#
>   # Since: 4.0
>   ##
>   
> @@ -706,7 +709,8 @@
>     'data': { 'initial': 'int',
>               'max': 'int',
>               'rounds': 'int',
> -            'step': 'int' } }
> +            'step': 'int',
> +            '*interfaces': ['str'] } }
>   
>   ##
>   # @announce-self:
> @@ -718,9 +722,10 @@
>   #
>   # Example:
>   #
> -# -> { "execute": "announce-self"
> +# -> { "execute": "announce-self",
>   #      "arguments": {
> -#          "initial": 50, "max": 550, "rounds": 10, "step": 50 } }
> +#          "initial": 50, "max": 550, "rounds": 10, "step": 50,
> +#          "interfaces": ["vn2", "vn3"] } }
>   # <- { "return": {} }
>   #
>   # Since: 4.0