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Subject: Re: [PATCH] rbtree: undo augmented damage -v2
From: Peter Zijlstra <peterz@infradead.org>
To: Suresh Siddha <suresh.b.siddha@intel.com>
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Date: Thu, 03 Jun 2010 09:13:46 +0200
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On Wed, 2010-06-02 at 14:11 -0700, Suresh Siddha wrote:
>       P                       SL
>     /  \                     /  \
>    N    S       --->        N    S
>   /   /  \                 /      \
>  C   SL  SR               C        SR
> 
> If P needs to be removed, we need to re-augment S also in this case,
> right? It looks like we are not handling this case.


rb_augment_erase_begin(P) will return S if I read the code right, so
rb_augment_path(S) will the re-augment S, SL, N.