From 362063a595be959bc08f4163e6405a0266740091 Mon Sep 17 00:00:00 2001 From: Scott Mayhew Date: Tue, 26 Mar 2019 18:06:28 -0400 Subject: [PATCH] nfsd: keep a tally of RECLAIM_COMPLETE operations when using nfsdcld When using nfsdcld for NFSv4 client tracking, track the number of RECLAIM_COMPLETE operations we receive from "known" clients to help in deciding if we can lift the grace period early (or whether we need to start a v4 grace period at all). Signed-off-by: Scott Mayhew Signed-off-by: J. Bruce Fields --- fs/nfsd/netns.h | 3 +++ fs/nfsd/nfs4recover.c | 3 +++ fs/nfsd/nfs4state.c | 33 ++++++++++++++++++++++++++++++++- fs/nfsd/nfsctl.c | 1 + 4 files changed, 39 insertions(+), 1 deletion(-) diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h index 32cb8c0..b42aaa2 100644 --- a/fs/nfsd/netns.h +++ b/fs/nfsd/netns.h @@ -104,6 +104,9 @@ struct nfsd_net { time_t nfsd4_grace; bool somebody_reclaimed; + bool track_reclaim_completes; + atomic_t nr_reclaim_complete; + bool nfsd_net_up; bool lockd_up; diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c index 89c2a27..09e3c93 100644 --- a/fs/nfsd/nfs4recover.c +++ b/fs/nfsd/nfs4recover.c @@ -1270,6 +1270,8 @@ nfs4_cld_state_init(struct net *net) for (i = 0; i < CLIENT_HASH_SIZE; i++) INIT_LIST_HEAD(&nn->reclaim_str_hashtbl[i]); nn->reclaim_str_hashtbl_size = 0; + nn->track_reclaim_completes = true; + atomic_set(&nn->nr_reclaim_complete, 0); return 0; } @@ -1279,6 +1281,7 @@ nfs4_cld_state_shutdown(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); + nn->track_reclaim_completes = false; kfree(nn->reclaim_str_hashtbl); } diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index e601416..8078314 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -77,6 +77,7 @@ static u64 current_sessionid = 1; /* forward declarations */ static bool check_for_locks(struct nfs4_file *fp, struct nfs4_lockowner *lowner); static void nfs4_free_ol_stateid(struct nfs4_stid *stid); +void nfsd4_end_grace(struct nfsd_net *nn); /* Locking: */ @@ -1997,6 +1998,22 @@ destroy_client(struct nfs4_client *clp) __destroy_client(clp); } +static void inc_reclaim_complete(struct nfs4_client *clp) +{ + struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); + + if (!nn->track_reclaim_completes) + return; + if (!nfsd4_find_reclaim_client(clp->cl_name, nn)) + return; + if (atomic_inc_return(&nn->nr_reclaim_complete) == + nn->reclaim_str_hashtbl_size) { + printk(KERN_INFO "NFSD: all clients done reclaiming, ending NFSv4 grace period (net %x)\n", + clp->net->ns.inum); + nfsd4_end_grace(nn); + } +} + static void expire_client(struct nfs4_client *clp) { unhash_client(clp); @@ -3348,6 +3365,7 @@ nfsd4_reclaim_complete(struct svc_rqst *rqstp, status = nfs_ok; nfsd4_client_record_create(cstate->session->se_client); + inc_reclaim_complete(cstate->session->se_client); out: return status; } @@ -4707,7 +4725,6 @@ nfsd4_end_grace(struct nfsd_net *nn) if (nn->grace_ended) return; - dprintk("NFSD: end of grace period\n"); nn->grace_ended = true; /* * If the server goes down again right now, an NFSv4 @@ -4743,6 +4760,10 @@ static bool clients_still_reclaiming(struct nfsd_net *nn) unsigned long double_grace_period_end = nn->boot_time + 2 * nn->nfsd4_lease; + if (nn->track_reclaim_completes && + atomic_read(&nn->nr_reclaim_complete) == + nn->reclaim_str_hashtbl_size) + return false; if (!nn->somebody_reclaimed) return false; nn->somebody_reclaimed = false; @@ -4773,6 +4794,7 @@ nfs4_laundromat(struct nfsd_net *nn) new_timeo = 0; goto out; } + dprintk("NFSD: end of grace period\n"); nfsd4_end_grace(nn); INIT_LIST_HEAD(&reaplist); spin_lock(&nn->client_lock); @@ -7261,10 +7283,19 @@ nfs4_state_start_net(struct net *net) return ret; locks_start_grace(net, &nn->nfsd4_manager); nfsd4_client_tracking_init(net); + if (nn->track_reclaim_completes && nn->reclaim_str_hashtbl_size == 0) + goto skip_grace; printk(KERN_INFO "NFSD: starting %ld-second grace period (net %x)\n", nn->nfsd4_grace, net->ns.inum); queue_delayed_work(laundry_wq, &nn->laundromat_work, nn->nfsd4_grace * HZ); return 0; + +skip_grace: + printk(KERN_INFO "NFSD: no clients to reclaim, skipping NFSv4 grace period (net %x)\n", + net->ns.inum); + queue_delayed_work(laundry_wq, &nn->laundromat_work, nn->nfsd4_lease * HZ); + nfsd4_end_grace(nn); + return 0; } /* initialization to perform when the nfsd service is started: */ diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index f2feb2d..6667d3a 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -1242,6 +1242,7 @@ static __net_init int nfsd_init_net(struct net *net) nn->nfsd4_lease = 90; /* default lease time */ nn->nfsd4_grace = 90; nn->somebody_reclaimed = false; + nn->track_reclaim_completes = false; nn->clverifier_counter = prandom_u32(); nn->clientid_counter = prandom_u32(); nn->s2s_cp_cl_id = nn->clientid_counter++; -- 2.7.4