Re: [PATCH 00/13] convert block layer to bioset_init()/mempool_init()

From: Christoph Hellwig
Date: Tue May 22 2018 - 01:47:06 EST


On Mon, May 21, 2018 at 07:38:55PM -0400, Kent Overstreet wrote:
> On Mon, May 21, 2018 at 02:24:32PM -0400, Mike Snitzer wrote:
> > Every single data structure change in this series should be reviewed for
> > unforeseen alignment consequences. Jens seemed to say that is
> > worthwhile. Not sure if he'll do it or we divide it up. If we divide
> > it up a temp topic branch should be published for others to inspect.
> >
> > Could be alignment hasn't been a historic concern for a bunch of the
> > data structures changed in this series.. if so then all we can do is fix
> > up any obvious potential for false sharing.
>
> Honestly, I almost never worry about alignment... the very few times I do care,
> I use __cacheline_aligned_in_smp.

And that generally is the right stratgey. If Mike really doesn't want
a change we can just open code the kmalloc for the bio set there, the
important point is that we should not keep the old API around for no
good reason.