Re: [PATCH 3/3] mm/swap: remove unneeded swap_active_head

[YoungJun Park <youngjun.park@lge.com>]

On Thu, Oct 09, 2025 at 10:09:56AM -0700, Chris Li wrote:
> Hi Baoquan,
> 
> On Thu, Oct 9, 2025 at 12:47 AM Baoquan He <bhe@redhat.com> wrote:
> >
> > By the way, Chris worried the plist swap_active_head could be reused by
> > the ongoing swap-tier work and suggested to hold off this patchset till
> > swap-tier work is clear. Now seems it won't impact swap-tier, I will
> > send a v2 against mm-new.
> 
> Sorry I haven't made it clear earlier. I withdraw the NACK because
> that is my misunderstanding of the code behavior. It does not mean I
> clear the swap tiers will not use swap_active_head yet, I actually
> haven't done that investigation.
> 
> I still suggest deferring this series which deletes the
> "swap_active_head". Wait until YoungPark's swap tiers to be sent out

Thanks Chris. 
"swap_active_head" is used on my current working patch.

> on the list. Let's wait for about 1 month or so, we should have a much

Yes, I am on the construct writing swap tier RFC.
it takes a few weeks to share on LKML.

> better understanding if the swap tiers series needs to use the
> "swap_active_head". We are not in a hurry to remove it, right? The
> earliest this can go into the official tree is 6.19 anyway. We still
> have some time.
> YoungPark, do you know if you want to use "swap_active_head" in your

On current version of my patch, I use "swap_active_head" 
on swap_tier assignment logic when traversing current swapfile.
It is efficient to use "swap_active_head" on traversing the swapfile 
in priority order.

I think about more on this part.

> pending patch series? Even better send your pending RFC patches to the
> list and Baoquan can collaborate on it.

As mentioned above, share it a few weeks later.

Thanks,
Youngjun Park