* Sasha Levin (levinsasha928@xxxxxxxxx) wrote: > On Sun, 2011-05-29 at 22:54 -0400, Mathieu Desnoyers wrote: > > Please note that what I currently have is a normal rbtree, not an > > interval rbtree. Can you elaborate on your use-case so I can try to > > figure out how we could augment it to support the interval rbtree you > > need ? > > We don't need anything specific for interval rbtree. The rbtree used in > the kernel provides augmentation functions for insert and erase (see > rb_augment_insert() and rb_augment_erase_begin() + > rb_augment_erase_end()). > What they basically do is call a user-provided callback for each node > from the newly inserted (or deepest after deletion) node up to the root > of the tree. You can see our code at 'tools/kvm/util/rbtree-interval.c', > basically all we need are the 2 augmentation functions I've mentioned > above. Given we have to update the parent nodes when the interval values change, we need to work on a copy of these parent nodes to ensure that their information about the children min/max corresponds to the children's left/right pointers they contain. Any discrepancy between their left/right pointers and the children min/max value they store would be invalid from a reader's POV. I'll see if I can embed this in my tree. It should be doable with the "decay" approach I am using. We'll need a way to test this though: possibly by walking the tree with range-aware lookups that also make sure that the ranges that were promised by the upper nodes are contained within their children at all times. Thanks, Mathieu -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
