Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qg0-f43.google.com ([209.85.192.43]:48118 "EHLO mail-qg0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761835AbaGRPNw (ORCPT ); Fri, 18 Jul 2014 11:13:52 -0400 Received: by mail-qg0-f43.google.com with SMTP id a108so3267939qge.2 for ; Fri, 18 Jul 2014 08:13:52 -0700 (PDT) From: Jeff Layton To: bfields@fieldses.org Cc: hch@infradead.org, linux-nfs@vger.kernel.org, Trond Myklebust Subject: [PATCH v4 06/10] nfsd: Convert delegation counter to an atomic_long_t type Date: Fri, 18 Jul 2014 11:13:32 -0400 Message-Id: <1405696416-32585-7-git-send-email-jlayton@primarydata.com> In-Reply-To: <1405696416-32585-1-git-send-email-jlayton@primarydata.com> References: <1405696416-32585-1-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 Reviewed-by: Christoph Hellwig --- 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 d11b298e625e..40def186ee50 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -343,7 +343,7 @@ find_any_file(struct nfs4_file *f) return ret; } -static int num_delegations; +static atomic_long_t num_delegations; unsigned long max_delegations; /* @@ -571,22 +571,23 @@ 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); @@ -594,6 +595,9 @@ 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) @@ -616,7 +620,7 @@ 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); } } -- 1.9.3