On Fri, Aug 18, 2023 at 04:10:49PM -0400, Jeff Layton wrote: > [...] > extra checks (supposedly) compile down to nothing. It should be possible > to build alternate refcount_t handling functions that are just wrappers > around atomic_t with no extra checks, for folks who want to really run > "fast and loose". No -- there's no benefit for this. We already did all this work years ago with the fast vs full break-down. All that got tossed out since it didn't matter. We did all the performance benchmarking and there was no meaningful difference -- refcount _is_ atomic with an added check that is branch-predicted away. Peter Zijlstra and Will Deacon spent a lot of time making it run smoothly. :) -Kees -- Kees Cook
