> On Feb 24, 2021, at 2:31 PM, J. Bruce Fields <bfields@xxxxxxxxxxxx> wrote:
>
> I confess I always have to stare at these comparisons for a minute to
> figure out which way they should go. And the logic in each of these
> loops is a little repetitive.
>
> Would it be worth creating a little state_expired() helper to work out
> the comparison and the new timeout?
That's better, but aren't there already operators on time64_t data objects
that can be used for this?
> --b.
>
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 61552e89bd89..00fb3603c29e 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -5363,6 +5363,22 @@ static bool clients_still_reclaiming(struct nfsd_net *nn)
> return true;
> }
>
> +struct laundry_time {
> + time64_t cutoff;
> + time64_t new_timeo;
> +};
> +
> +bool state_expired(struct laundry_time *lt, time64_t last_refresh)
> +{
> + time64_t time_remaining;
> +
> + if (last_refresh > lt->cutoff)
> + return true;
> + time_remaining = lt->cutoff - last_refresh;
> + lt->new_timeo = min(lt->new_timeo, time_remaining);
> + return false;
> +}
> +
> static time64_t
> nfs4_laundromat(struct nfsd_net *nn)
> {
> @@ -5372,14 +5388,16 @@ nfs4_laundromat(struct nfsd_net *nn)
> struct nfs4_ol_stateid *stp;
> struct nfsd4_blocked_lock *nbl;
> struct list_head *pos, *next, reaplist;
> - time64_t cutoff = ktime_get_boottime_seconds() - nn->nfsd4_lease;
> - time64_t t, new_timeo = nn->nfsd4_lease;
> + struct laundry_time lt = {
> + .cutoff = ktime_get_boottime_seconds() - nn->nfsd4_lease,
> + .new_timeo = nn->nfsd4_lease
> + };
> struct nfs4_cpntf_state *cps;
> copy_stateid_t *cps_t;
> int i;
>
> if (clients_still_reclaiming(nn)) {
> - new_timeo = 0;
> + lt.new_timeo = 0;
> goto out;
> }
> nfsd4_end_grace(nn);
> @@ -5389,7 +5407,7 @@ nfs4_laundromat(struct nfsd_net *nn)
> idr_for_each_entry(&nn->s2s_cp_stateids, cps_t, i) {
> cps = container_of(cps_t, struct nfs4_cpntf_state, cp_stateid);
> if (cps->cp_stateid.sc_type == NFS4_COPYNOTIFY_STID &&
> - cps->cpntf_time < cutoff)
> + state_expired(<, cps->cpntf_time))
> _free_cpntf_state_locked(nn, cps);
> }
> spin_unlock(&nn->s2s_cp_lock);
> @@ -5397,11 +5415,8 @@ nfs4_laundromat(struct nfsd_net *nn)
> spin_lock(&nn->client_lock);
> list_for_each_safe(pos, next, &nn->client_lru) {
> clp = list_entry(pos, struct nfs4_client, cl_lru);
> - if (clp->cl_time > cutoff) {
> - t = clp->cl_time - cutoff;
> - new_timeo = min(new_timeo, t);
> + if (!state_expired(<, clp->cl_time))
> break;
> - }
> if (mark_client_expired_locked(clp)) {
> trace_nfsd_clid_expired(&clp->cl_clientid);
> continue;
> @@ -5418,11 +5433,8 @@ nfs4_laundromat(struct nfsd_net *nn)
> spin_lock(&state_lock);
> list_for_each_safe(pos, next, &nn->del_recall_lru) {
> dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
> - if (dp->dl_time > cutoff) {
> - t = dp->dl_time - cutoff;
> - new_timeo = min(new_timeo, t);
> + if (!state_expired(<, clp->cl_time))
> break;
> - }
> WARN_ON(!unhash_delegation_locked(dp));
> list_add(&dp->dl_recall_lru, &reaplist);
> }
> @@ -5438,11 +5450,8 @@ nfs4_laundromat(struct nfsd_net *nn)
> while (!list_empty(&nn->close_lru)) {
> oo = list_first_entry(&nn->close_lru, struct nfs4_openowner,
> oo_close_lru);
> - if (oo->oo_time > cutoff) {
> - t = oo->oo_time - cutoff;
> - new_timeo = min(new_timeo, t);
> + if (!state_expired(<, oo->oo_time))
> break;
> - }
> list_del_init(&oo->oo_close_lru);
> stp = oo->oo_last_closed_stid;
> oo->oo_last_closed_stid = NULL;
> @@ -5468,11 +5477,8 @@ nfs4_laundromat(struct nfsd_net *nn)
> while (!list_empty(&nn->blocked_locks_lru)) {
> nbl = list_first_entry(&nn->blocked_locks_lru,
> struct nfsd4_blocked_lock, nbl_lru);
> - if (nbl->nbl_time > cutoff) {
> - t = nbl->nbl_time - cutoff;
> - new_timeo = min(new_timeo, t);
> + if (!state_expired(<, oo->oo_time))
> break;
> - }
> list_move(&nbl->nbl_lru, &reaplist);
> list_del_init(&nbl->nbl_list);
> }
> @@ -5485,8 +5491,7 @@ nfs4_laundromat(struct nfsd_net *nn)
> free_blocked_lock(nbl);
> }
> out:
> - new_timeo = max_t(time64_t, new_timeo, NFSD_LAUNDROMAT_MINTIMEOUT);
> - return new_timeo;
> + return max_t(time64_t, lt.new_timeo, NFSD_LAUNDROMAT_MINTIMEOUT);
> }
>
> static struct workqueue_struct *laundry_wq;
--
Chuck Lever
