Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qa0-f48.google.com ([209.85.216.48]:60724 "EHLO mail-qa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751511AbaFZTOx (ORCPT ); Thu, 26 Jun 2014 15:14:53 -0400 Received: by mail-qa0-f48.google.com with SMTP id x12so3210830qac.35 for ; Thu, 26 Jun 2014 12:14:52 -0700 (PDT) From: Jeff Layton To: bfields@fieldses.org Cc: linux-nfs@vger.kernel.org, Trond Myklebust Subject: [PATCH v2 049/117] nfsd: Convert delegation counter to an atomic_long_t type Date: Thu, 26 Jun 2014 15:12:29 -0400 Message-Id: <1403810017-16062-50-git-send-email-jlayton@primarydata.com> In-Reply-To: <1403810017-16062-1-git-send-email-jlayton@primarydata.com> References: <1403810017-16062-1-git-send-email-jlayton@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: From: Trond Myklebust 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 --- 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 6e918aa0829c..714273b942ce 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -338,7 +338,7 @@ static struct file *find_any_file(struct nfs4_file *f) return ret; } -static int num_delegations; +static atomic_long_t num_delegations; unsigned long max_delegations; /* @@ -548,7 +548,7 @@ static struct nfs4_ol_stateid * nfs4_alloc_stateid(struct nfs4_client *clp) static void nfs4_free_deleg(struct nfs4_stid *stid) { nfs4_free_stid(deleg_slab, stid); - num_delegations--; + atomic_long_dec(&num_delegations); } /* @@ -628,15 +628,17 @@ 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; dp->dl_stid.sc_free = nfs4_free_deleg; /* @@ -645,13 +647,15 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_ol_stateid *stp, struct sv * 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); dp->dl_type = NFS4_OPEN_DELEGATE_READ; fh_copy_shallow(&dp->dl_fh, ¤t_fh->fh_handle); return dp; +out_dec: + atomic_long_dec(&num_delegations); + return NULL; } static void remove_stid_locked(struct nfs4_client *clp, struct nfs4_stid *s) -- 1.9.3