On Thu, Jul 12, 2012 at 7:12 AM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > On Wed, 2012-07-11 at 18:12 -0700, Michel Lespinasse wrote: >> >> In __rb_erase_color(), some of the cases are more complicated than you drew however, because some node colors aren't known. > > Right, the wikipedia article draws them blank, I couldn't come up with a > 3rd case, although maybe we can annotate them like (P) to mean blank.. Ah, good idea, I adopted that :) > Yes, very nice.. someday when I'm bored I might expand the comments with > the reason why we're doing the given operation. There is a brief comment at the start of the loop that indicates which rbtree invariants might be violated at that point; so someone could deduce that we're trying to either fix these or move towards the root until they get fixed. But yeah, this is never explicitly explained. > Also, I was sorely tempted to rename your tmp1,tmp2 variables to sl and > sr. This could be done, but you'd *still* need one extra temporary, so you'd end up with sl, sr and tmp. Which is fine, I guess, but I preferred to have one less variable around. -- Michel "Walken" Lespinasse A program is never fully debugged until the last user dies. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>