Return-Path: Received: from mail-io0-f194.google.com ([209.85.223.194]:42687 "EHLO mail-io0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728973AbeICWB7 (ORCPT ); Mon, 3 Sep 2018 18:01:59 -0400 Received: by mail-io0-f194.google.com with SMTP id n18-v6so926109ioa.9 for ; Mon, 03 Sep 2018 10:40:48 -0700 (PDT) Message-ID: Subject: Re: [PATCH 05/27] SUNRPC: Avoid holding locks across the XDR encoding of the RPC message From: Trond Myklebust To: Chuck Lever Cc: Linux NFS Mailing List Date: Mon, 03 Sep 2018 13:40:45 -0400 In-Reply-To: <3CB8AF72-4F0E-4273-B91E-FB4A28124E29@gmail.com> References: <20180903152936.24325-1-trond.myklebust@hammerspace.com> <20180903152936.24325-2-trond.myklebust@hammerspace.com> <20180903152936.24325-3-trond.myklebust@hammerspace.com> <20180903152936.24325-4-trond.myklebust@hammerspace.com> <20180903152936.24325-5-trond.myklebust@hammerspace.com> <20180903152936.24325-6-trond.myklebust@hammerspace.com> <3CB8AF72-4F0E-4273-B91E-FB4A28124E29@gmail.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon, 2018-09-03 at 13:11 -0400, Chuck Lever wrote: > > On Sep 3, 2018, at 11:29 AM, Trond Myklebust > > wrote: > > > > Currently, we grab the socket bit lock before we allow the message > > to be XDR encoded. That significantly slows down the transmission > > rate, since we serialise on a potentially blocking operation. > > Which operation blocks, and how often? RPCSEC_GSS allocates memory when doing privacy encoding, for instance. > > Signed-off-by: Trond Myklebust > > --- > > net/sunrpc/clnt.c | 8 ++++---- > > 1 file changed, 4 insertions(+), 4 deletions(-) > > > > diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c > > index e5ac35e803ad..66ec61347716 100644 > > --- a/net/sunrpc/clnt.c > > +++ b/net/sunrpc/clnt.c > > @@ -1949,9 +1949,6 @@ call_transmit(struct rpc_task *task) > > task->tk_action = call_status; > > if (task->tk_status < 0) > > return; > > - if (!xprt_prepare_transmit(task)) > > - return; > > - task->tk_action = call_transmit_status; > > /* Encode here so that rpcsec_gss can use correct sequence > > number. */ > > if (rpc_task_need_encode(task)) { > > rpc_xdr_encode(task); > > @@ -1965,8 +1962,11 @@ call_transmit(struct rpc_task *task) > > return; > > } > > } > > + if (!xprt_prepare_transmit(task)) > > + return; > > + task->tk_action = call_transmit_status; > > xprt_transmit(task); > > - if (task->tk_status < 0) > > + if (task->tk_status < 0) { > > The added curly bracket seems incorrect. Oops. Yes, that's a rebase brain-fart... Thanks for spotting it! > > > > return; > > if (is_retrans) > > task->tk_client->cl_stats->rpcretrans++; > > -- > > 2.17.1 > > > > -- > Chuck Lever > chucklever@gmail.com > > >