Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:31803 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932579AbbGJU3E convert rfc822-to-8bit (ORCPT ); Fri, 10 Jul 2015 16:29:04 -0400 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: [PATCH v1 05/12] xprtrdma: Account for RPC/RDMA header size when deciding to inline From: Chuck Lever In-Reply-To: <55A02650.1050809@Netapp.com> Date: Fri, 10 Jul 2015 16:28:56 -0400 Cc: linux-rdma@vger.kernel.org, Linux NFS Mailing List Message-Id: <7D23C297-3DA3-4C44-836E-3A0671CB31ED@oracle.com> References: <20150709203242.26247.4848.stgit@manet.1015granger.net> <20150709204227.26247.51111.stgit@manet.1015granger.net> <55A02650.1050809@Netapp.com> To: Anna Schumaker Sender: linux-nfs-owner@vger.kernel.org List-ID: On Jul 10, 2015, at 4:08 PM, Anna Schumaker wrote: > Hi Chuck, > > On 07/09/2015 04:42 PM, Chuck Lever wrote: >> When marshaling RPC/RDMA requests, ensure the combined size of >> RPC/RDMA header and RPC header do not exceed the inline threshold. >> Endpoints typically reject RPC/RDMA messages that exceed the size >> of their receive buffers. >> >> Signed-off-by: Chuck Lever >> --- >> net/sunrpc/xprtrdma/rpc_rdma.c | 29 +++++++++++++++++++++++++++-- >> 1 file changed, 27 insertions(+), 2 deletions(-) >> >> diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c >> index 84ea37d..8cf9402 100644 >> --- a/net/sunrpc/xprtrdma/rpc_rdma.c >> +++ b/net/sunrpc/xprtrdma/rpc_rdma.c >> @@ -71,6 +71,31 @@ static const char transfertypes[][12] = { >> }; >> #endif >> >> +/* The client can send a request inline as long as the RPCRDMA header >> + * plus the RPC call fit under the transport's inline limit. If the >> + * combined call message size exceeds that limit, the client must use >> + * the read chunk list for this operation. >> + */ >> +static bool rpcrdma_args_inline(struct rpc_rqst *rqst) >> +{ >> + unsigned int callsize = RPCRDMA_HDRLEN_MIN + rqst->rq_snd_buf.len; >> + >> + return callsize <= RPCRDMA_INLINE_WRITE_THRESHOLD(rqst); >> +} >> + >> +/* The client can?t know how large the actual reply will be. Thus it > ^^^^^ > This is showing up as "can<80><99>t" in git-show, leading me to think that the apostrophe was replaced with a unicode-apostrophe. Google might have made the switch, but can you double check the patch on your side just in case? Fixed. > > Thanks, > Anna > >> + * plans for the largest possible reply for that particular ULP >> + * operation. If the maximum combined reply message size exceeds that >> + * limit, the client must provide a write list or a reply chunk for >> + * this request. >> + */ >> +static bool rpcrdma_results_inline(struct rpc_rqst *rqst) >> +{ >> + unsigned int repsize = RPCRDMA_HDRLEN_MIN + rqst->rq_rcv_buf.buflen; >> + >> + return repsize <= RPCRDMA_INLINE_READ_THRESHOLD(rqst); >> +} >> + >> /* >> * Chunk assembly from upper layer xdr_buf. >> * >> @@ -418,7 +443,7 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst) >> * a READ, then use write chunks to separate the file data >> * into pages; otherwise use reply chunks. >> */ >> - if (rqst->rq_rcv_buf.buflen <= RPCRDMA_INLINE_READ_THRESHOLD(rqst)) >> + if (rpcrdma_results_inline(rqst)) >> wtype = rpcrdma_noch; >> else if (rqst->rq_rcv_buf.page_len == 0) >> wtype = rpcrdma_replych; >> @@ -441,7 +466,7 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst) >> * implies the op is a write. >> * TBD check NFSv4 setacl >> */ >> - if (rqst->rq_snd_buf.len <= RPCRDMA_INLINE_WRITE_THRESHOLD(rqst)) >> + if (rpcrdma_args_inline(rqst)) >> rtype = rpcrdma_noch; >> else if (rqst->rq_snd_buf.page_len == 0) >> rtype = rpcrdma_areadch; >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > -- Chuck Lever