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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 CDB5BC43381 for ; Thu, 21 Mar 2019 13:19:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A642620830 for ; Thu, 21 Mar 2019 13:19:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728342AbfCUNS3 (ORCPT ); Thu, 21 Mar 2019 09:18:29 -0400 Received: from mail-il-dmz.mellanox.com ([193.47.165.129]:42350 "EHLO mellanox.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728319AbfCUNS2 (ORCPT ); Thu, 21 Mar 2019 09:18:28 -0400 Received: from Internal Mail-Server by MTLPINE1 (envelope-from vladbu@mellanox.com) with ESMTPS (AES256-SHA encrypted); 21 Mar 2019 15:18:25 +0200 Received: from reg-r-vrt-018-180.mtr.labs.mlnx. (reg-r-vrt-018-180.mtr.labs.mlnx [10.213.18.180]) by labmailer.mlnx (8.13.8/8.13.8) with ESMTP id x2LDIPdL019148; Thu, 21 Mar 2019 15:18:25 +0200 From: Vlad Buslov To: netdev@vger.kernel.org Cc: jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us, davem@davemloft.net, sbrivio@redhat.com, Vlad Buslov Subject: [PATCH net-next v3 02/12] net: sched: flower: refactor fl_change Date: Thu, 21 Mar 2019 15:17:34 +0200 Message-Id: <20190321131744.19224-3-vladbu@mellanox.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190321131744.19224-1-vladbu@mellanox.com> References: <20190321131744.19224-1-vladbu@mellanox.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org As a preparation for using classifier spinlock instead of relying on external rtnl lock, rearrange code in fl_change. The goal is to group the code which changes classifier state in single block in order to allow following commits in this set to protect it from parallel modification with tp->lock. Data structures that require tp->lock protection are mask hashtable and filters list, and classifier handle_idr. fl_hw_replace_filter() is a sleeping function and cannot be called while holding a spinlock. In order to execute all sequence of changes to shared classifier data structures atomically, call fl_hw_replace_filter() before modifying them. Signed-off-by: Vlad Buslov Reviewed-by: Stefano Brivio --- net/sched/cls_flower.c | 80 ++++++++++++++++++++++-------------------- 1 file changed, 41 insertions(+), 39 deletions(-) diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index dcf3aee5697e..d36ceb5001f9 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -1376,73 +1376,75 @@ static int fl_change(struct net *net, struct sk_buff *in_skb, if (err) goto errout; - if (!handle) { - handle = 1; - err = idr_alloc_u32(&head->handle_idr, fnew, &handle, - INT_MAX, GFP_KERNEL); - } else if (!fold) { - /* user specifies a handle and it doesn't exist */ - err = idr_alloc_u32(&head->handle_idr, fnew, &handle, - handle, GFP_KERNEL); - } - if (err) - goto errout_mask; - fnew->handle = handle; - - if (!fold && __fl_lookup(fnew->mask, &fnew->mkey)) { - err = -EEXIST; - goto errout_idr; - } - - err = rhashtable_insert_fast(&fnew->mask->ht, &fnew->ht_node, - fnew->mask->filter_ht_params); - if (err) - goto errout_idr; - if (!tc_skip_hw(fnew->flags)) { err = fl_hw_replace_filter(tp, fnew, extack); if (err) - goto errout_mask_ht; + goto errout_mask; } if (!tc_in_hw(fnew->flags)) fnew->flags |= TCA_CLS_FLAGS_NOT_IN_HW; if (fold) { + fnew->handle = handle; + + err = rhashtable_insert_fast(&fnew->mask->ht, &fnew->ht_node, + fnew->mask->filter_ht_params); + if (err) + goto errout_hw; + rhashtable_remove_fast(&fold->mask->ht, &fold->ht_node, fold->mask->filter_ht_params); - if (!tc_skip_hw(fold->flags)) - fl_hw_destroy_filter(tp, fold, NULL); - } - - *arg = fnew; - - if (fold) { idr_replace(&head->handle_idr, fnew, fnew->handle); list_replace_rcu(&fold->list, &fnew->list); + + if (!tc_skip_hw(fold->flags)) + fl_hw_destroy_filter(tp, fold, NULL); tcf_unbind_filter(tp, &fold->res); tcf_exts_get_net(&fold->exts); tcf_queue_work(&fold->rwork, fl_destroy_filter_work); } else { + if (__fl_lookup(fnew->mask, &fnew->mkey)) { + err = -EEXIST; + goto errout_hw; + } + + if (handle) { + /* user specifies a handle and it doesn't exist */ + err = idr_alloc_u32(&head->handle_idr, fnew, &handle, + handle, GFP_ATOMIC); + } else { + handle = 1; + err = idr_alloc_u32(&head->handle_idr, fnew, &handle, + INT_MAX, GFP_ATOMIC); + } + if (err) + goto errout_hw; + + fnew->handle = handle; + + err = rhashtable_insert_fast(&fnew->mask->ht, &fnew->ht_node, + fnew->mask->filter_ht_params); + if (err) + goto errout_idr; + list_add_tail_rcu(&fnew->list, &fnew->mask->filters); } + *arg = fnew; + kfree(tb); kfree(mask); return 0; -errout_mask_ht: - rhashtable_remove_fast(&fnew->mask->ht, &fnew->ht_node, - fnew->mask->filter_ht_params); - errout_idr: - if (!fold) - idr_remove(&head->handle_idr, fnew->handle); - + idr_remove(&head->handle_idr, fnew->handle); +errout_hw: + if (!tc_skip_hw(fnew->flags)) + fl_hw_destroy_filter(tp, fnew, NULL); errout_mask: fl_mask_put(head, fnew->mask, false); - errout: tcf_exts_destroy(&fnew->exts); kfree(fnew); -- 2.21.0