On Nov 16, 2022, at 10:44 PM, Dai Ngo [off-list ref] wrote:

This patch series adds:

   . refactor courtesy_client_reaper to a generic low memory
     shrinker.

   . XDR encode and decode function for CB_RECALL_ANY op.

   . the delegation reaper that sends the advisory CB_RECALL_ANY 
     to the clients to release unused delegations.
     There is only one nfsd4_callback added for each nfs4_cleint.
     Access to it must be serialized via the client flag
     NFSD4_CLIENT_CB_RECALL_ANY.

   . Add CB_RECALL_ANY tracepoints.

v2:
   . modify deleg_reaper to check and send CB_RECALL_ANY to client
     only once per 5 secs.
v3:
   . modify nfsd4_cb_recall_any_release to use nn->client_lock to
     protect cl_recall_any_busy and call put_client_renew_locked
     to decrement cl_rpc_users.

v4:
   . move changes in nfs4state.c from patch (1/2) to patch(2/2).
   . use xdr_stream_encode_u32 and xdr_stream_encode_uint32_array
     to encode CB_RECALL_ANY arguments.
   . add struct nfsd4_cb_recall_any with embedded nfs4_callback
     and params for CB_RECALL_ANY op.
   . replace cl_recall_any_busy boolean with client flag
     NFSD4_CLIENT_CB_RECALL_ANY 
   . add tracepoints for CB_RECALL_ANY

v5:
   . refactor courtesy_client_reaper to a generic low memory
     shrinker
   . merge courtesy client shrinker and delegtion shrinker into
     one.
   . reposition nfsd_cb_recall_any and nfsd_cb_recall_any_done
     in nfsd/trace.h
   . use __get_sockaddr to display server IP address in
     tracepoints.
   . modify encode_cb_recallany4args to replace sizeof with
     ARRAY_SIZE.

Hi-

I'm going to apply this version of the series with some minor
changes. I'll reply to the individual patches where we can
discuss those.

---

Dai Ngo (4):
    NFSD: refactoring courtesy_client_reaper to a generic low memory shrinker
    NFSD: add support for sending CB_RECALL_ANY
    NFSD: add delegation shrinker to react to low memory condition
    NFSD: add CB_RECALL_ANY tracepoints

fs/nfsd/nfs4callback.c |  62 +++++++++++++++++++++++
fs/nfsd/nfs4state.c    | 116 +++++++++++++++++++++++++++++++++++++++-----
fs/nfsd/state.h        |   9 ++++
fs/nfsd/trace.h        |  49 +++++++++++++++++++
fs/nfsd/xdr4.h         |   5 ++
fs/nfsd/xdr4cb.h       |   6 +++
6 files changed, 234 insertions(+), 13 deletions(-)

--
Chuck Lever