[libvirt] [PATCH] bandwidth: Require network QoS if interface uses 'floor'

[Laine Stump]

On 03/07/2013 05:02 AM, Michal Privoznik wrote:
> By current implementation, network inbound is required in order
> to use 'floor' for guaranteeing  minimal throughput. This is so,
> because we want user to tell us the maximal throughput of the
> network instead of finding out ourselves (and detect bogus values
> in case of virtual interfaces). However, we are nowadays
> requiring this only on documentation level. So if user starts a
> domain with 'floor' set on one its interfaces, we silently ignore
> the setting. We should error out instead.
> ---
>  src/network/bridge_driver.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
> index 31c8585..330c147 100644
> --- a/src/network/bridge_driver.c
> +++ b/src/network/bridge_driver.c
> @@ -4535,11 +4535,22 @@ networkCheckBandwidth(virNetworkObjPtr net,
>      unsigned long long tmp_new_rate = 0;
>      char ifmac[VIR_MAC_STRING_BUFLEN];
>  
> +    virMacAddrFormat(&iface->mac, ifmac);
> +
> +    if (ifaceBand && ifaceBand->in && ifaceBand->in->floor &&
> +        !(netBand && netBand->in)) {
> +        virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
> +                       _("Cannot use 'floor' on %s because network '%s' "
> +                         "does not have any inbound QoS set"),

How about "Invalid use of 'floor' on interface with mac address %s -
network '%s' has no inbound QoS set"

> +                       ifmac, net->def->name);
> +        return -1;
> +    }
> +
>      if (!ifaceBand || !ifaceBand->in || !ifaceBand->in->floor ||
> -        !netBand || !netBand->in)
> +        !netBand || !netBand->in) {
> +        /* no QoS required, claim success */
>          return 1;
> -
> -    virMacAddrFormat(&iface->mac, ifmac);
> +    }
>  
>      tmp_new_rate = netBand->in->average;
>      tmp_floor_sum += ifaceBand->in->floor;

Looks safe enough. ACK with or without a changed log message.