On Mon, Mar 20, 2017 at 4:32 PM, Andy Zhou <az...@ovn.org> wrote: > With the introduction of open flow 'clone' action, the OVS user space > can now translate the 'clone' action into kernel datapath 'sample' > action, with 100% probability, to ensure that the clone semantics, > which is that the packet seen by the clone action is the same as the > packet seen by the action after clone, is faithfully carried out > in the datapath. > > While the sample action in the datpath has the matching semantics, > its implementation is only optimized for its original use. > Specifically, there are two limitation: First, there is a 3 level of > nesting restriction, enforced at the flow downloading time. This > limit turns out to be too restrictive for the 'clone' use case. > Second, the implementation avoid recursive call only if the sample > action list has a single userspace action. > > The main optimization implemented in this series removes the static > nesting limit check, instead, implement the run time recursion limit > check, and recursion avoidance similar to that of the 'recirc' action. > This optimization solve both #1 and #2 issues above. > > One related optimization attempts to avoid copying flow key as > long as the actions enclosed does not change the flow key. The > detection is performed only once at the flow downloading time. > > Another related optimization is to rewrite the action list > at flow downloading time in order to save the fast path from parsing > the sample action list in its original form repeatedly. > > Signed-off-by: Andy Zhou <az...@ovn.org>
Acked-by: Pravin B Shelar <pshe...@ovn.org>
