Re: [for-6.13 PATCH v3 00/14] nfs/nfsd: improvements for LOCALIO

[Anna Schumaker <anna.schumaker@oracle.com>]

On 12/18/24 12:31 PM, Mike Snitzer wrote:
> On Fri, Nov 22, 2024 at 09:31:23PM -0500, Mike Snitzer wrote:
>> On Fri, Nov 22, 2024 at 12:26:39PM -0500, Jeff Layton wrote:
>>> On Fri, 2024-11-15 at 20:40 -0500, Mike Snitzer wrote:
>>>> Hi,
>>>>
>>>> All available here:
>>>> https://git.kernel.org/pub/scm/linux/kernel/git/snitzer/linux.git/log/?h=nfs-localio-for-next
>>>>
>>>> Changes since v2:
>>>> - switched from rcu_assign_pointer to RCU_INIT_POINTER when setting to
>>>>   NULL.
>>>> - removed some unnecessary #if IS_ENABLED(CONFIG_NFS_LOCALIO)
>>>> - revised the NFS v3 probe patch to use a new nfsv3.ko modparam
>>>>   'nfs3_localio_probe_throttle' to control if NFSv3 will probe for
>>>>   LOCALIO. Avoids use of NFS_CS_LOCAL_IO and will probe every
>>>>   'nfs3_localio_probe_throttle' IO requests (defaults to 0, disabled).
>>>> - added "Module Parameters" section to localio.rst
>>>>
>>>> All review appreciated, thanks.
>>>> Mike
>>>>
>>>> Mike Snitzer (14):
>>>>   nfs/localio: add direct IO enablement with sync and async IO support
>>>>   nfsd: add nfsd_file_{get,put} to 'nfs_to' nfsd_localio_operations
>>>>   nfs_common: rename functions that invalidate LOCALIO nfs_clients
>>>>   nfs_common: move localio_lock to new lock member of nfs_uuid_t
>>>>   nfs: cache all open LOCALIO nfsd_file(s) in client
>>>>   nfsd: update percpu_ref to manage references on nfsd_net
>>>>   nfsd: rename nfsd_serv_ prefixed methods and variables with nfsd_net_
>>>>   nfsd: nfsd_file_acquire_local no longer returns GC'd nfsd_file
>>>>   nfs_common: rename nfslocalio nfs_uuid_lock to nfs_uuids_lock
>>>>   nfs_common: track all open nfsd_files per LOCALIO nfs_client
>>>>   nfs_common: add nfs_localio trace events
>>>>   nfs/localio: remove redundant code and simplify LOCALIO enablement
>>>>   nfs: probe for LOCALIO when v4 client reconnects to server
>>>>   nfs: probe for LOCALIO when v3 client reconnects to server
>>>>
>>>>  Documentation/filesystems/nfs/localio.rst |  98 +++++----
>>>>  fs/nfs/client.c                           |   6 +-
>>>>  fs/nfs/direct.c                           |   1 +
>>>>  fs/nfs/flexfilelayout/flexfilelayout.c    |  25 +--
>>>>  fs/nfs/flexfilelayout/flexfilelayout.h    |   1 +
>>>>  fs/nfs/inode.c                            |   3 +
>>>>  fs/nfs/internal.h                         |   9 +-
>>>>  fs/nfs/localio.c                          | 232 +++++++++++++++-----
>>>>  fs/nfs/nfs3proc.c                         |  46 +++-
>>>>  fs/nfs/nfs4state.c                        |   1 +
>>>>  fs/nfs/nfstrace.h                         |  32 ---
>>>>  fs/nfs/pagelist.c                         |   5 +-
>>>>  fs/nfs/write.c                            |   3 +-
>>>>  fs/nfs_common/Makefile                    |   3 +-
>>>>  fs/nfs_common/localio_trace.c             |  10 +
>>>>  fs/nfs_common/localio_trace.h             |  56 +++++
>>>>  fs/nfs_common/nfslocalio.c                | 250 +++++++++++++++++-----
>>>>  fs/nfsd/filecache.c                       |  20 +-
>>>>  fs/nfsd/localio.c                         |   9 +-
>>>>  fs/nfsd/netns.h                           |  12 +-
>>>>  fs/nfsd/nfsctl.c                          |   6 +-
>>>>  fs/nfsd/nfssvc.c                          |  40 ++--
>>>>  include/linux/nfs_fs.h                    |  22 +-
>>>>  include/linux/nfs_fs_sb.h                 |   3 +-
>>>>  include/linux/nfs_xdr.h                   |   1 +
>>>>  include/linux/nfslocalio.h                |  48 +++--
>>>>  26 files changed, 674 insertions(+), 268 deletions(-)
>>>>  create mode 100644 fs/nfs_common/localio_trace.c
>>>>  create mode 100644 fs/nfs_common/localio_trace.h
>>>>
>>>
>>> I went through the set and it looks mostly sane to me. The one concern
>>> I have is that you have the client set up to start caching nfsd files
>>> before there is a mechanism to call it and ask them to return them. You
>>> might see some weird behavior there on a bisect, but it looks like it
>>> all gets resolved in the end.
>>
>> Yeah, couldn't see a better way to atomically pivot to the new disable
>> functionality without it needing to be a large muddled patch.
>>
>> Shouldn't be bad even if someone did bisect, its only the server being
>> restarted during LOCALIO that could see issues (unlikely thing for
>> someone to be testing for specifically with a bisect).
>>
>>> How do you intend for this to go in? Since most of this is client side,
>>> will this be going in via Trond/Anna's tree?
>>
>> Yes, likely easiest to have it go through Trond/Anna's tree.  Trond
>> did have it in his testing tree, maybe your Reviewed-by helps it all
>> land.
>>
>>> You can add:
>>>
>>> Reviewed-by: Jeff Layton <jlayton@kernel.org>
>>
>> Thanks,
>> Mike
>>
> 
> Hi all,
> 
> These LOCALIO changes didn't land for 6.13 merge, please advise on if
> we might get these changes staged for 6.14 now-ish.

Works for me.

> 
> Trond and/or Anna, do you feel comfortable picking this series up
> (nfsd cachnges too) or would you like to see any changes before that
> is possible?

I'll go through the patches once more, but they should be fine. I will need Acked-by's for the NFSD bits from Chuck or Jeff.

Anna

> 
> Thanks,
> Mike