Re: [PATCH 0/4] mm: Use slab_list list_head instead of lru
From: Roman Gushchin
Date: Tue Mar 12 2019 - 13:22:03 EST
On Tue, Mar 12, 2019 at 01:01:53PM +1100, Tobin C. Harding wrote:
> On Tue, Mar 12, 2019 at 12:22:23AM +0000, Roman Gushchin wrote:
> > On Mon, Mar 11, 2019 at 04:16:33PM -0700, Matthew Wilcox wrote:
> > > On Mon, Mar 11, 2019 at 08:49:23PM +0000, Roman Gushchin wrote:
> > > > The patchset looks good to me, however I'd add some clarifications
> > > > why switching from lru to slab_list is safe.
> > > >
> > > > My understanding is that the slab_list fields isn't currently in use,
> > > > but it's not that obvious that putting slab_list and next/pages/pobjects
> > > > fields into a union is safe (for the slub case).
> > >
> > > It's already in a union.
> > >
> > > struct page {
> > > union {
> > > struct { /* Page cache and anonymous pages */
> > > struct list_head lru;
> > > ...
> > > struct { /* slab, slob and slub */
> > > union {
> > > struct list_head slab_list; /* uses lru */
> > > struct { /* Partial pages */
> > > struct page *next;
> > >
> > > slab_list and lru are in the same bits. Once this patch set is in,
> > > we can remove the enigmatic 'uses lru' comment that I added.
> >
> > Ah, perfect, thanks! Makes total sense then.
> >
> > Tobin, can you, please, add a note to the commit message?
> > With the note:
> > Reviewed-by: Roman Gushchin <guro@xxxxxx>
>
> Awesome, thanks. That's for all 4 patches or excluding 2?
To all 4, given that you'll add some explanations to the commit message.
Thanks!