Messages in this thread | | | Date | Tue, 1 Jun 2010 11:09:23 -0700 | Subject | Re: [PATCH] rbtree: undo augmented damage -v2 | From | Venkatesh Pallipadi <> |
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On Tue, Jun 1, 2010 at 10:42 AM, Peter Zijlstra <peterz@infradead.org> wrote: > On Tue, 2010-06-01 at 10:34 -0700, Venkatesh Pallipadi wrote: >> >> Yes. This will cover all the cases on insert. But on erase, there is >> still a case where a rotate of sibling node is done during the >> re-coloration process. There we have a child change on sibling's >> child. I am not able to think of any easy way to handle that case. > > Let me go draw some figures with pen and paper to match up the erase > path with the rb_augment_erase_begin() code, because I can't quite spot > the case we're missing. > > If you have it handy, ascii art might help..
It is this case
P / \ N S / \ SL SR
changing to
P / \ N SL \ S \ SR
This can happen in __rb_erase_color, where 'other' points to sibling node.
Thanks, Venki
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