Re: [RFC] change non-atomic bitops method

David Miller
2015-02-03T08:40:34Z

From: Andrew Morton <akpm@linux-foundation.org>
Date: Mon, 2 Feb 2015 22:38:51 -0800

> It is only with both these ratios that we can work out whether the
> patch is a net gain. My suspicion is that set_bit on an already-set
> bit is so rare that the patch will be a loss.

A common pattern is implementing a "referenced" bit, and in that case
the bit is often already set, and in such a scenerio the proposed
change is a huge win.