Laine Stump 250435546a util: make it optional to clear existing tc qdiscs/filters in virNetDevBandwidthSet()
virNetDevBandwidthSet() always clears all existing qdiscs and their
subordinate filters before adding all the new qdiscs/filters. This is
normally exactly what we want, but there is one case (the network
driver) where the Qdisc added by virNetDevBandwidthSet() may already
be in use by the nftables backend (which will add a rule to fix the
checksum of dhcp packets); in that case, we *don't* want
virNetDevBandwidthSet() to clear out the qdisc that was already added
for nftables, and none of the bandwidth filters have been added yet,
so there already aren't any "old" filters that need to be removed
either - it is safe to just skip virNetDevBandwidthClear() in this
case.

To allow the network driver to set bandwidth without first clearing
it, this patch adds the flag VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL to the
virNetDevBandwidthSetFlags enum, and recognizes it in
virNetDevBandwidthSet() - if the flag is set, then
virNetDevBandwidth() will call virNetDevBandwidthClear() just as it
always has. But if the flag isn't set it *won't* call
virNetDevBandwidthClear().

As suggested above, VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL is set for all
calls to virNetdevBandwidthSet() except for two places in the network
driver.

Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2024-11-26 14:36:14 +01:00
..
2024-11-12 15:35:53 +01:00