Re: [PATCH v4 0/2] NFSD: memory shrinker for NFSv4 clients

[Jeff Layton <jlayton@kernel.org>]

On Tue, 2022-08-30 at 14:48 -0700, Dai Ngo wrote:
> This patch series implements the memory shrinker for NFSv4 clients
> to react to system low memory condition.
> 
> The memory shrinker's count callback is used to trigger the laundromat.
> The actual work of destroying the expired clients is done by the
> laundromat itself. We can not destroying the expired clients on the
> memory shrinler's scan callback context to avoid possible deadlock.
> 
> By destroying the expired clients, all states associated with these
> clients are also released.
> 
> v2:
> . fix kernel test robot errors in nfsd.h when CONFIG_NFSD_V4 not defined.
> 
> v3:
> . add mod_delayed_work in nfsd_courtesy_client_scan to kick start
>   the laundromat.
> 
> v4:
> . replace the use of xchg() with vanilla '=' in patch 1.
> 
> ---
> 
> Dai Ngo (2):
>       NFSD: keep track of the number of courtesy clients in the system
>       NFSD: add shrinker to reap courtesy clients on low memory condition
> 
>  fs/nfsd/netns.h     |  5 ++++
>  fs/nfsd/nfs4state.c | 65 ++++++++++++++++++++++++++++++++++++++++++++----
>  fs/nfsd/nfsctl.c    |  6 +++--
>  fs/nfsd/nfsd.h      |  9 +++++--
>  4 files changed, 76 insertions(+), 9 deletions(-)

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