Thanks! It looks good to me on a first skim, but I probably won't get a proper look at it till next week. You say "RFC"--are there still known issue that you're working on? --b. On Tue, Mar 26, 2019 at 06:06:25PM -0400, Scott Mayhew wrote: > When nfsdcld was released, it was quickly deprecated in favor of the > nfsdcltrack usermodehelper, so as to not require another running daemon. > That prevents NFSv4 clients from reclaiming locks from nfsd's running in > containers, since neither nfsdcltrack nor the legacy client tracking > code work in containers. These patches un-deprecate the use of nfsdcld > for NFSv4 client tracking. > > These patches are intended to go alongside some nfs-utils patches that > introduce an enhancement that allows nfsd to "slurp" up the client > records during client tracking initialization and store them internally > in hash table. This enables nfsd to check whether an NFSv4 client is > allowed to reclaim without having to do an upcall to nfsdcld. It also > allows nfsd to decide to end the v4 grace period early if the number of > RECLAIM_COMPLETE operations it has received from "known" clients is > equal to the number of entries in the hash table. It also allows nfsd > to skip the v4 grace period altogether if it knows there are no clients > allowed to reclaim. > > There is a fallback to allow nfsd to continue to work with older nfsdcld > daemons in the event that any are out in the wild (unlikely). > Everything should work fine except nfsd will not be able to exit the > grace period early or skip the grace period altogether. > > v3: > - nfs4_state_start_net() now calls nfsd4_end_grace() instead of > open-coding it > - Removed some unnecessary initializations of nr_reclaim_complete > - Removed dec_reclaim_complete() altogether. If we're calling > expire_client() as a result of receiving a DESTROY_CLIENTID or > SETCLIENTID_CONFIRM then we wouldn't want to decrement the count. And > laundromat thread never expires clients due to loss of lease until the > grace period is over (the laundromat gets rescheduled by 1 second as > long as clients are reclaiming during that 1 second, for up to 2x the > original grace period in total). So dec_reclaim_complete() is > unnecessary. > - Changed the preference order of client tracking methods. The new > order is 1) new nfdscld, 2) old nfsdcld, 3) nfsdcltrack, 4) legacy > v4recovery directory. > - Added some special handling of legacy records sent by nfsdcld in the > GraceStart downcalls. nfsdcld will do a one-time "upgrade" from old > tracking methods. No changes are needed to accomodate nfsdcltrack > records, but legacy records will be prefixed with the string "hash:", > and in the event that we do have legacy records in the > reclaim_str_hashtbl we may need to do a second lookup using the hash > in the event that a lookup using the client name string fails. > > v2: > - Addressed some coding style issues in nfsd4_create_clid_dir() & > nfsd4_remove_clid_dir() > > Scott Mayhew (5): > nfsd: make nfs4_client_reclaim use an xdr_netobj instead of a fixed > char array > nfsd: un-deprecate nfsdcld > nfsd: keep a tally of RECLAIM_COMPLETE operations when using nfsdcld > nfsd: re-order client tracking method selection > nfsd: handle legacy client tracking records sent by nfsdcld > > fs/nfsd/netns.h | 3 + > fs/nfsd/nfs4recover.c | 436 +++++++++++++++++++++++++++++++--- > fs/nfsd/nfs4state.c | 63 +++-- > fs/nfsd/nfsctl.c | 1 + > fs/nfsd/state.h | 8 +- > include/uapi/linux/nfsd/cld.h | 1 + > 6 files changed, 457 insertions(+), 55 deletions(-) > > -- > 2.17.2
