Re: (subset) [PATCH 22/32] vfs: inode cache conversion to hash-bl

From: Mateusz Guzik
Date: Thu Oct 19 2023 - 11:31:01 EST


On Tue, May 23, 2023 at 11:28:38AM +0200, Christian Brauner wrote:
> On Tue, 09 May 2023 12:56:47 -0400, Kent Overstreet wrote:
> > Because scalability of the global inode_hash_lock really, really
> > sucks.
> >
> > 32-way concurrent create on a couple of different filesystems
> > before:
> >
> > - 52.13% 0.04% [kernel] [k] ext4_create
> > - 52.09% ext4_create
> > - 41.03% __ext4_new_inode
> > - 29.92% insert_inode_locked
> > - 25.35% _raw_spin_lock
> > - do_raw_spin_lock
> > - 24.97% __pv_queued_spin_lock_slowpath
> >
> > [...]
>
> This is interesting completely independent of bcachefs so we should give
> it some testing.
>
> I updated a few places that had outdated comments.
>
> ---
>
> Applied to the vfs.unstable.inode-hash branch of the vfs/vfs.git tree.
> Patches in the vfs.unstable.inode-hash branch should appear in linux-next soon.
>
> Please report any outstanding bugs that were missed during review in a
> new review to the original patch series allowing us to drop it.
>
> It's encouraged to provide Acked-bys and Reviewed-bys even though the
> patch has now been applied. If possible patch trailers will be updated.
>
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
> branch: vfs.unstable.inode-hash
>
> [22/32] vfs: inode cache conversion to hash-bl
> https://git.kernel.org/vfs/vfs/c/e3e92d47e6b1

What, if anything, is blocking this? It is over 5 months now, I don't
see it in master nor -next.

To be clear there is no urgency as far as I'm concerned, but I did run
into something which is primarily bottlenecked by inode hash lock and
looks like the above should sort it out.

Looks like the patch was simply forgotten.

tl;dr can this land in -next please