From patchwork Mon Apr 19 18:02:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever III X-Patchwork-Id: 12212407 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1FA43C433B4 for ; Mon, 19 Apr 2021 18:02:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F11B761107 for ; Mon, 19 Apr 2021 18:02:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240473AbhDSSCf (ORCPT ); Mon, 19 Apr 2021 14:02:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:40862 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240433AbhDSSCe (ORCPT ); Mon, 19 Apr 2021 14:02:34 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7A02D61001; Mon, 19 Apr 2021 18:02:04 +0000 (UTC) Subject: [PATCH v3 04/26] xprtrdma: Avoid Receive Queue wrapping From: Chuck Lever To: trondmy@hammerspace.com Cc: linux-nfs@vger.kernel.org, linux-rdma@vger.kernel.org Date: Mon, 19 Apr 2021 14:02:03 -0400 Message-ID: <161885532369.38598.5198559642333362919.stgit@manet.1015granger.net> In-Reply-To: <161885481568.38598.16682844600209775665.stgit@manet.1015granger.net> References: <161885481568.38598.16682844600209775665.stgit@manet.1015granger.net> User-Agent: StGit/0.23-29-ga622f1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org Commit e340c2d6ef2a ("xprtrdma: Reduce the doorbell rate (Receive)") increased the number of Receive WRs that are posted by the client, but did not increase the size of the Receive Queue allocated during transport set-up. This is usually not an issue because RPCRDMA_BACKWARD_WRS is defined as (32) when SUNRPC_BACKCHANNEL is defined. In cases where it isn't, there is a real risk of Receive Queue wrapping. Fixes: e340c2d6ef2a ("xprtrdma: Reduce the doorbell rate (Receive)") Signed-off-by: Chuck Lever Reviewed-by: Tom Talpey --- net/sunrpc/xprtrdma/frwr_ops.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c index 766a1048a48a..132df9b59ab4 100644 --- a/net/sunrpc/xprtrdma/frwr_ops.c +++ b/net/sunrpc/xprtrdma/frwr_ops.c @@ -257,6 +257,7 @@ int frwr_query_device(struct rpcrdma_ep *ep, const struct ib_device *device) ep->re_attr.cap.max_send_wr += 1; /* for ib_drain_sq */ ep->re_attr.cap.max_recv_wr = ep->re_max_requests; ep->re_attr.cap.max_recv_wr += RPCRDMA_BACKWARD_WRS; + ep->re_attr.cap.max_recv_wr += RPCRDMA_MAX_RECV_BATCH; ep->re_attr.cap.max_recv_wr += 1; /* for ib_drain_rq */ ep->re_max_rdma_segs =