I was looking through the radix tree code and came across what I think
is a bug in radix_tree_delete.

	for (idx = 0; idx < RADIX_TREE_TAG_LONGS; idx++) {
		if (pathp[0].node->tags[tag][idx]) {
			tags[tag] = 1;
			nr_cleared_tags--;
			break;
		}
	}

The above loop should only be executed if tags[tag] is zero.  Otherwise,
when walking up the tree, we can decrement nr_cleared_tags twice or more
for the same value of tag, thus potentially exiting the outer loop too
early.

Ensure that nr_cleared_tags is only decremented once for each tag.
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>