Re: [PATCH 0/5] Minor NFSD global DRC clean-ups

[Jeff Layton <jlayton@kernel.org>]

On Thu, 2026-07-16 at 20:12 -0400, Chuck Lever wrote:
> I'm working on a series of global DRC improvements. A few minor
> clean-ups are ready for merge now.
> 
> Chuck Lever (5):
>   NFSD: Fix off-by-one in DRC bucket pruning limit
>   NFSD: Eliminate percpu counter contention in DRC memory accounting
>   NFSD: Eliminate percpu counter contention in reply cache statistics
>   NFSD: Eliminate percpu counter contention in IO byte accounting
>   NFSD: Document reply_cache_stats ABI
> 
>  .../ABI/testing/procfs-nfsd-reply_cache_stats | 38 +++++++++
>  fs/nfsd/nfscache.c                            |  2 +-
>  fs/nfsd/stats.h                               | 78 ++++++++++++++++---
>  3 files changed, 108 insertions(+), 10 deletions(-)
>  create mode 100644 Documentation/ABI/testing/procfs-nfsd-reply_cache_stats

I had no idea that percpu counters could devolve into spinlocking in
certain conditions. Ick. I wonder if we need to do a pass over all of
our percpu counter usage for the same sort of thing. ISTM that we
pretty much always want to use the *_local versions for our use-cases.

In any case, for this series:

Reviewed-by: Jeff Layton <jlayton@kernel.org>