From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63875C433EF for ; Fri, 25 Feb 2022 16:45:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232865AbiBYQpn (ORCPT ); Fri, 25 Feb 2022 11:45:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229922AbiBYQpn (ORCPT ); Fri, 25 Feb 2022 11:45:43 -0500 Received: from out30-44.freemail.mail.aliyun.com (out30-44.freemail.mail.aliyun.com [115.124.30.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F1A91F9829; Fri, 25 Feb 2022 08:45:09 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R171e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04400;MF=alibuda@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0V5Tsmgd_1645807506; Received: from 30.15.226.221(mailfrom:alibuda@linux.alibaba.com fp:SMTPD_---0V5Tsmgd_1645807506) by smtp.aliyun-inc.com(127.0.0.1); Sat, 26 Feb 2022 00:45:07 +0800 Message-ID: <45837d14-7895-4aff-43a3-a5ad6ef80c2d@linux.alibaba.com> Date: Sat, 26 Feb 2022 00:45:06 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.5.1 Subject: Re: [PATCH net] net/smc: fix unexpected SMC_CLC_DECL_ERR_REGRMB error From: "D. Wythe" To: kgraul@linux.ibm.com Cc: kuba@kernel.org, davem@davemloft.net, netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org References: <1645776708-66113-1-git-send-email-alibuda@linux.alibaba.com> In-Reply-To: <1645776708-66113-1-git-send-email-alibuda@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org 在 2022/2/25 下午4:11, D. Wythe 写道: > From: "D. Wythe" > > Remove connections from link group is not synchronous with handling > SMC_LLC_DELETE_RKEY, which means that even the number of connections is > less that SMC_RMBS_PER_LGR_MAX, it does not mean that the connection can > register rtoken successfully later, in other words, the rtoken entry may > have not been released. This will cause an unexpected > SMC_CLC_DECL_ERR_REGRMB to be reported, and then ths smc connection have > to fallback to TCP. > > Therefore, we need to judge according to the number of idle rtoken > entry. > > Fixes: cd6851f30386 ("smc: remote memory buffers (RMBs)") > Signed-off-by: D. Wythe > --- > net/smc/smc_core.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c > index 29525d0..24ef0af 100644 > --- a/net/smc/smc_core.c > +++ b/net/smc/smc_core.c > @@ -1864,7 +1864,8 @@ int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) > (ini->smcd_version == SMC_V2 || > lgr->vlan_id == ini->vlan_id) && > (role == SMC_CLNT || ini->is_smcd || > - lgr->conns_num < SMC_RMBS_PER_LGR_MAX)) { > + lgr->conns_num < SMC_RMBS_PER_LGR_MAX - > + bitmap_weight(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX))) { > /* link group found */ > ini->first_contact_local = 0; > conn->lgr = lgr; I did a horrible math here, i'll send another fix later. Best wishes.