On Thu, Jun 07, 2018 at 12:13:01PM +0200, Jakub Sitnicki wrote: > Promoting secondary addresses on address removal makes flushing all > addresses from a device with 1000's of them slow. This is because we > cannot take down the secondary addresses when we are removing the > primary one, which would make it faster. > > However, the userspace, when performing a flush, will in the end remove > all the addresses regardless of secondary address promotion taking > place. Unfortunately the kernel currently cannot distinguish between a > single address removal and a flush of all addresses. > > To help with this case introduce a IFA_F_FLUSH flag that can be used by > userspace to signal that a removal operation is being done because of a > flush. When the flag is set, don't bother with secondary address > promotion as we expect that secondary addresses will be removed soon as > well.
Unless you intend to use the flag to allow deleting a specific address with its secondaries (overriding promote_secondaries), maybe it would be more practical to go even further and delete all addresses on the interface if IFA_F_FLUSH is set so that userspace could delete all addresses with one request. Michal Kubecek
