From patchwork Fri Aug 26 09:51:29 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "D. Wythe" X-Patchwork-Id: 12955798 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 C631DECAAD2 for ; Fri, 26 Aug 2022 09:52:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344085AbiHZJwK (ORCPT ); Fri, 26 Aug 2022 05:52:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344066AbiHZJwE (ORCPT ); Fri, 26 Aug 2022 05:52:04 -0400 Received: from out199-9.us.a.mail.aliyun.com (out199-9.us.a.mail.aliyun.com [47.90.199.9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 60DF4D83D4; Fri, 26 Aug 2022 02:51:57 -0700 (PDT) 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=ay29a033018045168;MF=alibuda@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0VNIa0Hk_1661507512; Received: from localhost(mailfrom:alibuda@linux.alibaba.com fp:SMTPD_---0VNIa0Hk_1661507512) by smtp.aliyun-inc.com; Fri, 26 Aug 2022 17:51:53 +0800 From: "D. Wythe" To: kgraul@linux.ibm.com, wenjia@linux.ibm.com Cc: kuba@kernel.org, davem@davemloft.net, netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org, "D. Wythe" Subject: [PATCH net-next v2 02/10] net/smc: fix SMC_CLC_DECL_ERR_REGRMB without smc_server_lgr_pending Date: Fri, 26 Aug 2022 17:51:29 +0800 Message-Id: X-Mailer: git-send-email 1.8.3.1 In-Reply-To: References: Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org From: "D. Wythe" As commit 4940a1fdf31c ("net/smc: fix unexpected SMC_CLC_DECL_ERR_REGRMB error cause by server") mentioned, it works only when all connection creations are completely protected by smc_server_lgr_pending, since we already remove this lock, we need to re-fix the issues. Fixes: 4940a1fdf31c ("net/smc: fix unexpected SMC_CLC_DECL_ERR_REGRMB error cause by server") Signed-off-by: D. Wythe --- net/smc/af_smc.c | 2 ++ net/smc/smc_core.c | 11 ++++++++--- net/smc/smc_core.h | 18 ++++++++++++++++++ 3 files changed, 28 insertions(+), 3 deletions(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index d0e6bec..ddca170 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -2411,6 +2411,7 @@ static void smc_listen_work(struct work_struct *work) if (rc) goto out_unlock; } + smc_conn_leave_rtoken_pending(new_smc, ini); smc_conn_save_peer_info(new_smc, cclc); smc_listen_out_connected(new_smc); SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini); @@ -2420,6 +2421,7 @@ static void smc_listen_work(struct work_struct *work) if (ini->is_smcd) mutex_unlock(&smc_server_lgr_pending); out_decl: + smc_conn_leave_rtoken_pending(new_smc, ini); smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0, proposal_version); out_free: diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index cfaddf2..f93c69f 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -2167,14 +2167,19 @@ int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) lgr->vlan_id == ini->vlan_id) && (role == SMC_CLNT || ini->is_smcd || (lgr->conns_num < SMC_RMBS_PER_LGR_MAX && - !bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) { + (SMC_RMBS_PER_LGR_MAX - + bitmap_weight(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) + > atomic_read(&lgr->rtoken_pendings))))) { /* link group found */ ini->first_contact_local = 0; conn->lgr = lgr; rc = smc_lgr_register_conn(conn, false); write_unlock_bh(&lgr->conns_lock); - if (!rc && delayed_work_pending(&lgr->free_work)) - cancel_delayed_work(&lgr->free_work); + if (!rc) { + smc_conn_enter_rtoken_pending(smc, ini); + if (delayed_work_pending(&lgr->free_work)) + cancel_delayed_work(&lgr->free_work); + } break; } write_unlock_bh(&lgr->conns_lock); diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index 3c3bc11..a304ef3 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -298,6 +298,9 @@ struct smc_link_group { struct rb_root conns_all; /* connection tree */ rwlock_t conns_lock; /* protects conns_all */ unsigned int conns_num; /* current # of connections */ + atomic_t rtoken_pendings;/* number of connection that + * lgr assigned but no rtoken got yet + */ unsigned short vlan_id; /* vlan id of link group */ struct list_head sndbufs[SMC_RMBE_SIZES];/* tx buffers */ @@ -609,6 +612,21 @@ struct smc_link *smc_switch_conns(struct smc_link_group *lgr, int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb); void smcr_link_cluster_on_link_state(struct smc_link *lnk); +static inline void smc_conn_enter_rtoken_pending(struct smc_sock *smc, struct smc_init_info *ini) +{ + struct smc_link_group *lgr = smc->conn.lgr; + + if (lgr && !ini->first_contact_local) + atomic_inc(&lgr->rtoken_pendings); +} + +static inline void smc_conn_leave_rtoken_pending(struct smc_sock *smc, struct smc_init_info *ini) +{ + struct smc_link_group *lgr = smc->conn.lgr; + + if (lgr && !ini->first_contact_local) + atomic_dec(&lgr->rtoken_pendings); +} static inline struct smc_link_group *smc_get_lgr(struct smc_link *link) {