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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 30FDEC433DF for ; Mon, 10 Aug 2020 11:03:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0ABB6206C3 for ; Mon, 10 Aug 2020 11:03:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726523AbgHJLD5 (ORCPT ); Mon, 10 Aug 2020 07:03:57 -0400 Received: from correo.us.es ([193.147.175.20]:49588 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726146AbgHJLDz (ORCPT ); Mon, 10 Aug 2020 07:03:55 -0400 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 5B8D6EB471 for ; Mon, 10 Aug 2020 13:03:54 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 4EB83DA78F for ; Mon, 10 Aug 2020 13:03:54 +0200 (CEST) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 4453ADA78B; Mon, 10 Aug 2020 13:03:54 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id E2B43DA801; Mon, 10 Aug 2020 13:03:51 +0200 (CEST) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Mon, 10 Aug 2020 13:03:51 +0200 (CEST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from us.es (unknown [90.77.255.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: 1984lsi) by entrada.int (Postfix) with ESMTPSA id C348D4265A2F; Mon, 10 Aug 2020 13:03:51 +0200 (CEST) Date: Mon, 10 Aug 2020 13:03:51 +0200 X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: Florian Westphal Cc: netfilter-devel@vger.kernel.org, lkp@lists.01.org, linux-kernel@vger.kernel.org, kernel test robot Subject: Re: [PATCH nf] netfilter: nft_compat: remove flush counter optimization Message-ID: <20200810110351.GA1613@salvia> References: <20200809063030.GA1538@shao2-debian> <20200809182801.9315-1-fw@strlen.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200809182801.9315-1-fw@strlen.de> User-Agent: Mutt/1.10.1 (2018-07-13) X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 09, 2020 at 08:28:01PM +0200, Florian Westphal wrote: > WARNING: CPU: 1 PID: 16059 at lib/refcount.c:31 refcount_warn_saturate+0xdf/0xf > [..] > __nft_mt_tg_destroy+0x42/0x50 [nft_compat] > nft_target_destroy+0x63/0x80 [nft_compat] > nf_tables_expr_destroy+0x1b/0x30 [nf_tables] > nf_tables_rule_destroy+0x3a/0x70 [nf_tables] > nf_tables_exit_net+0x186/0x3d0 [nf_tables] > > Happens when a compat expr is destoyed from abort path. > There is no functional impact; after this work queue is flushed > unconditionally if its pending. > > This removes the waitcount optimization. Test of repeated > iptables-restore of a ~60k kubernetes ruleset doesn't indicate > a slowdown. In case the counter is needed after all for some workloads > we can revert this and increment the refcount for the > != NFT_PREPARE_TRANS case to avoid the increment/decrement imbalance. > > While at it, also flush for match case, this was an oversight > in the original patch. Applied, thanks.