Messages in this thread | | | Date | Fri, 20 Oct 2017 18:22:27 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH] lib/int_sqrt.c: optimize for small argument values |
| |
On Fri, Oct 20, 2017 at 07:18:51AM -0700, Kees Cook wrote: > On Thu, Oct 19, 2017 at 11:13 PM, Joe Perches <joe@perches.com> wrote: > > On Thu, 2017-10-19 at 13:31 -0700, Michael Davidson wrote: > >> int_sqrt() currently takes approximately constant time > >> regardless of the value of the argument. By using the > >> magnitude of the operand to set the initial conditions > >> for the calculation the cost becomes proportional to > >> log2 of the argument with the worst case behavior not > >> being measurably slower than it currently is. > > > > https://lkml.org/lkml/2017/7/24/408 > > Ah! Cool. I don't see this version queued up for -next. Where does > Peter's version stand?
Oh, crud, forgot all about it. I'd have to double check I addressed the concerns Linus had with my Changelogs, but other than that he seemed to be OK.
| |