Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:52328 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752406AbaIIUqS (ORCPT ); Tue, 9 Sep 2014 16:46:18 -0400 Date: Tue, 9 Sep 2014 16:46:17 -0400 From: "J. Bruce Fields" To: Jeff Layton Cc: linux-nfs@vger.kernel.org, steved@redhat.com Subject: Re: [PATCH v3 7/8] nfsd: set and test NFSD4_CLIENT_STABLE bit to reduce nfsdcltrack upcalls Message-ID: <20140909204617.GC17979@fieldses.org> References: <1410187609-10319-1-git-send-email-jlayton@primarydata.com> <1410187609-10319-8-git-send-email-jlayton@primarydata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1410187609-10319-8-git-send-email-jlayton@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon, Sep 08, 2014 at 10:46:48AM -0400, Jeff Layton wrote: > The nfsdcltrack upcall doesn't utilize the NFSD4_CLIENT_STABLE flag, > which basically results in an upcall every time we call into the client > tracking ops. > > Change it to set this bit on a successful "check" or "create" request, > and clear it on a "remove" request. Also, check to see if that bit is > set before upcalling on a "check" or "remove" request, and skip > upcalling appropriately, depending on its state. > > Signed-off-by: Jeff Layton > --- > fs/nfsd/nfs4recover.c | 22 ++++++++++++++++++---- > 1 file changed, 18 insertions(+), 4 deletions(-) > > diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c > index ae313861a6f5..5697e9d2e875 100644 > --- a/fs/nfsd/nfs4recover.c > +++ b/fs/nfsd/nfs4recover.c > @@ -1291,7 +1291,8 @@ nfsd4_umh_cltrack_create(struct nfs4_client *clp) > grace_start = nfsd4_cltrack_grace_start(nn->boot_time); > > nfsd4_cltrack_upcall_lock(clp); > - nfsd4_umh_cltrack_upcall("create", hexid, reclaim_complete, grace_start); > + if (!nfsd4_umh_cltrack_upcall("create", hexid, reclaim_complete, grace_start)) > + set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); Don't you also want to skip the upcall when STABLE is set? (Not a big deal in the 4.1 case as it's only called once per client (in RECLAIM_COMPLETE) but annoying in the 4.0 case where it's called on every OPEN_CONFIRM.) --b. > nfsd4_cltrack_upcall_unlock(clp); > > kfree(reclaim_complete); > @@ -1304,6 +1305,9 @@ nfsd4_umh_cltrack_remove(struct nfs4_client *clp) > { > char *hexid; > > + if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) > + return; > + > hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len); > if (!hexid) { > dprintk("%s: can't allocate memory for upcall!\n", __func__); > @@ -1311,7 +1315,9 @@ nfsd4_umh_cltrack_remove(struct nfs4_client *clp) > } > > nfsd4_cltrack_upcall_lock(clp); > - nfsd4_umh_cltrack_upcall("remove", hexid, NULL, NULL); > + if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags) && > + nfsd4_umh_cltrack_upcall("remove", hexid, NULL, NULL) == 0) > + clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); > nfsd4_cltrack_upcall_unlock(clp); > > kfree(hexid); > @@ -1323,6 +1329,9 @@ nfsd4_umh_cltrack_check(struct nfs4_client *clp) > int ret; > char *hexid, *legacy; > > + if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) > + return 0; > + > hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len); > if (!hexid) { > dprintk("%s: can't allocate memory for upcall!\n", __func__); > @@ -1331,9 +1340,14 @@ nfsd4_umh_cltrack_check(struct nfs4_client *clp) > legacy = nfsd4_cltrack_legacy_recdir(&clp->cl_name); > > nfsd4_cltrack_upcall_lock(clp); > - ret = nfsd4_umh_cltrack_upcall("check", hexid, legacy, NULL); > + if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) { > + ret = 0; > + } else { > + ret = nfsd4_umh_cltrack_upcall("check", hexid, legacy, NULL); > + if (!ret) > + set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); > + } > nfsd4_cltrack_upcall_unlock(clp); > - > kfree(legacy); > kfree(hexid); > return ret; > -- > 1.9.3 >