Messages in this thread | | | Date | Sun, 12 Apr 2009 10:29:52 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH 1/3] radix-tree: add radix_tree_prev_hole() |
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On Sun, 12 Apr 2009 15:19:51 +0800 Wu Fengguang <fengguang.wu@intel.com> wrote:
> +unsigned long radix_tree_prev_hole(struct radix_tree_root *root, > + unsigned long index, unsigned long max_scan) > +{ > + unsigned long i; > + > + for (i = 0; i < max_scan; i++) { > + if (!radix_tree_lookup(root, index)) > + break; > + index--; > + if (index == LONG_MAX) > + break; > + } > + > + return index; > +}
argh. This is about as inefficient as we could possibly make it :(
Really, this function should dive into radix-tree internals and walk individual radix_tree_node.slots[] arrays. And heck, it can peek at radix_tree_node.count and _bypass_ entire nodes, too.
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