Re: [PATCH] char/mem: only use {read,write}_iter, not the old {read,write} functions

Jason A. Donenfeld
2022-05-20T15:24:36Z

Hi Al,

On Fri, May 20, 2022 at 03:09:19PM +0000, Al Viro wrote:
> On Fri, May 20, 2022 at 03:50:30PM +0200, Jason A. Donenfeld wrote:
> > Currently mem.c implements both the {read,write}_iter functions and the
> > {read,write} functions. But with {read,write} going away at some point
> > in the future,
>
> Not likely to happen, unfortunately.
>
> > and most kernel code made to prefer {read,write}_iter,
> > there's no point in keeping around the old code.
>
> Profile and you'll see ;-/

Huh, yea, I lose around 1 GiB/s of perf on my machine sending /dev/zero
into /dev/null.

Jason