"Denis V. Lunev" <den@xxxxx> writes: > Hello, All! > > During port of Eric's patches I have noticed an interesting thing. > The patch "net: Teach the ipv4 route cache to handle multiple network > namespaces" call hold_net for each IPv4 DST cache entry. > > Though it is not possible to stop a namespace without stopping all the > devices inside. Additionally, the device can't be unregistered if there > are dst entries to it. These entries are moved to a namespace loopback > and the namespace will block until these entries will gone from a loopback. > > So, I do not see a necessity to have an extra atomic on this hot path, > i.e. hold_net can re moved away for this. Are there any holes? So all hold_net is good for is to catch logic errors where people are still using a network namespace but have freed it. It is a bit like the device reference count in that regard. The usage of the dst cache from ipv4 looked complicated enough that making some small mistake easy to have so I included the reference count for good measure. If the movement to loopback device is sufficient to prevent us from goofing up in this area I am happy to avoid the reference count. Eric _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
