On Sat, Apr 23, 2022 at 11:44:08AM -0700, Dai Ngo wrote: > . Redo based on Bruce's suggestion by breaking the patches into functionality > and also don't remove client record of courtesy client until the client is > actually expired. > > 0001: courteous server framework with support for client with delegation only. > This patch also handles COURTESY and EXPIRABLE reconnect. > Conflict is resolved by set the courtesy client to EXPIRABLE, let the > laundromat expires the client on next run and return NFS4ERR_DELAY > OPEN request. > > 0002: add support for opens/share reservation to courteous server > Conflict is resolved by set the courtesy client to EXPIRABLE, let the > laundromat expires the client on next run and return NFS4ERR_DELAY > OPEN request. > > 0003: mv creation/destroying laundromat workqueue from nfs4_state_start and > and nfs4_state_shutdown_net to init_nfsd and exit_nfsd. > > 0004: fs/lock: add locks_owner_has_blockers helper > > 0005: add 2 callbacks to lock_manager_operations for resolving lock conflict > > 0006: add support for locks to courteous server, making use of 0004 and 0005 > Conflict is resolved by set the courtesy client to EXPIRABLE, run the > laundromat immediately and wait for it to complete before returning to > fs/lock code to recheck the lock list from the beginning. > > NOTE: I could not get queue_work/queue_delay_work and flush_workqueue > to work as expected, I have to use mod_delayed_work and flush_workqueue > to get the laundromat to run immediately. Whoops, yes, my bad. > When we check for blockers in nfs4_anylock_blockers, we do not check > for client with delegation conflict. This is because we already hold > the client_lock and to check for delegation conflict we need the state_lock > and scanning the del_recall_lru list each time. So to avoid this overhead > and potential deadlock (not sure about lock of ordering of these locks) > we check and set the COURTESY client with delegation being recalled to > EXPIRABLE later in nfs4_laundromat. Hm, OK, I'll think about that, but sounds like it should work. --b. > > 0007: show state of courtesy client in client info.
