Re: [PATCH v4 12/13] fair.c: Use generic rbtree impl in fair scheduler

Peter Zijlstra
2012-06-27T12:37:09Z

On Tue, 2012-06-26 at 16:59 -0500, Daniel Santos wrote:
> Also, to address why we're not using entity_before (or a less()
> function) directly, there's two main reasons (one that doesn't even
> affect CFS). The first reason is that an "is equal" evaluation would
> also be required for insertions in trees with unique keys,

Right, I saw that feature in your code, are there any such trees in the
kernel? It would be good to have a kernel code conversion for each
variant your code supports.

> as well as
> all lookups. This doesn't doesn't affect CFS because it isn't doing
> lookups (it only cares about leftmost) and duplicate keys are allowed.
>
Right.. there's that.

Too bad, partial order is slightly cheaper at times. A well, nothing for
it.