Re: [PATCH 0/3] remove rw_page() from brd, pmem and btt

From: Andrew Morton
Date: Fri Jul 28 2017 - 17:21:31 EST


On Fri, 28 Jul 2017 10:31:43 -0700 Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:

> On Fri, Jul 28, 2017 at 10:56:01AM -0600, Ross Zwisler wrote:
> > Dan Williams and Christoph Hellwig have recently expressed doubt about
> > whether the rw_page() interface made sense for synchronous memory drivers
> > [1][2]. It's unclear whether this interface has any performance benefit
> > for these drivers, but as we continue to fix bugs it is clear that it does
> > have a maintenance burden. This series removes the rw_page()
> > implementations in brd, pmem and btt to relieve this burden.
>
> Why don't you measure whether it has performance benefits? I don't
> understand why zram would see performance benefits and not other drivers.
> If it's going to be removed, then the whole interface should be removed,
> not just have the implementations removed from some drivers.

Yes please. Minchan, could you please take a look sometime?