From 02a3508dba9a58b7bd77cc91f8e941e2dda94d1d Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 25 Jul 2014 07:34:22 -0400 Subject: [PATCH] nfsd: Convert delegation counter to an atomic_long_t type We want to convert to an atomic type so that we don't need to lock across the call to alloc_init_deleg(). Then convert to a long type so that we match the size of 'max_delegations'. None of this is a problem today, but it will be once we remove client_mutex protection. Signed-off-by: Trond Myklebust Reviewed-by: Christoph Hellwig Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4state.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 9c912c004247..b421b51c3a9e 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -342,7 +342,7 @@ find_any_file(struct nfs4_file *f) return ret; } -static int num_delegations; +static atomic_long_t num_delegations; unsigned long max_delegations; /* @@ -582,22 +582,23 @@ static struct nfs4_delegation * alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct svc_fh *current_fh) { struct nfs4_delegation *dp; + long n; dprintk("NFSD alloc_init_deleg\n"); - if (num_delegations > max_delegations) - return NULL; + n = atomic_long_inc_return(&num_delegations); + if (n < 0 || n > max_delegations) + goto out_dec; if (delegation_blocked(¤t_fh->fh_handle)) - return NULL; + goto out_dec; dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab)); if (dp == NULL) - return dp; + goto out_dec; /* * delegation seqid's are never incremented. The 4.1 special * meaning of seqid 0 isn't meaningful, really, but let's avoid * 0 anyway just for consistency and use 1: */ dp->dl_stid.sc_stateid.si_generation = 1; - num_delegations++; INIT_LIST_HEAD(&dp->dl_perfile); INIT_LIST_HEAD(&dp->dl_perclnt); INIT_LIST_HEAD(&dp->dl_recall_lru); @@ -605,6 +606,9 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct sv fh_copy_shallow(&dp->dl_fh, ¤t_fh->fh_handle); INIT_WORK(&dp->dl_recall.cb_work, nfsd4_run_cb_recall); return dp; +out_dec: + atomic_long_dec(&num_delegations); + return NULL; } static void remove_stid(struct nfs4_stid *s) @@ -627,7 +631,7 @@ nfs4_put_delegation(struct nfs4_delegation *dp) put_nfs4_file(dp->dl_file); remove_stid(&dp->dl_stid); nfs4_free_stid(deleg_slab, &dp->dl_stid); - num_delegations--; + atomic_long_dec(&num_delegations); } } -- 2.20.1