Re: [Lsf-pc] [LSF/MM/BPF TOPIC] Removing GFP_NOFS

Dave Chinner
2024-01-09T22:23:42Z

On Tue, Jan 09, 2024 at 07:43:54AM +0000, Johannes Thumshirn wrote:
> On 08.01.24 18:40, David Sterba wrote:
> >> 199 - btrfs
> >
> > All the easy conversions to scoped nofs allocaionts have been done, the
> > rest requires to add saving the nofs state at the transactions tart, as
> > said in above. I have a wip series for that, updated every few releases
> > but it's intrusive and not finished for a testing run. The number of
> > patches is over 100, doing each conversion separately, the other generic
> > changes are straightforward.
> >
> > It's possible to do it incrementally, there's one moster patch (300
> > edited lines) to add a stub parameter to transaction start,
> > https://lore.kernel.org/linux-btrfs/20211018173803.18353-1-dsterba@suse.com/ .
> > There are some counter points in the discussion if it has to be done
> > like that but IIRC it's not possible, I have examples why not.
> >
>
> At a first glance, storing the nofs scope in the transaction handle like
> Filipe proposed sounds like a good idea to me.

That's exactly what XFS has done for the last couple of decades. :)

Cheers,

Dave.
--
Dave Chinner
david@fromorbit.com