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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 C6C2FC63798 for ; Mon, 16 Nov 2020 15:58:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7A0D520A8B for ; Mon, 16 Nov 2020 15:58:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="QPNj0RJB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730663AbgKPP6G (ORCPT ); Mon, 16 Nov 2020 10:58:06 -0500 Received: from mail.kernel.org ([198.145.29.99]:40070 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730473AbgKPP6F (ORCPT ); Mon, 16 Nov 2020 10:58:05 -0500 Received: from kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com (unknown [163.114.132.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 96E9D20A8B; Mon, 16 Nov 2020 15:58:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605542284; bh=5/W5YHREqFFasn1uY6bRpOswAoCpvHqJsGYAbOijz14=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=QPNj0RJBqE4bNWKSYXCVp3++nattwyn4mWK0DEt1g9a1SnarWw7t4bhCfBMcTXp77 IH0OraBVdp/0MTyRamS1qGfANOo7PtsYZ0MKDjE1yCvt2HX4euQEnFkEA6Oc9Arqbd KV6L0NKJ2WsPGuSr3B6EwP4K5Hi16n9opMBIvAS8= Date: Mon, 16 Nov 2020 07:58:03 -0800 From: Jakub Kicinski To: Heiner Kallweit Cc: David Miller , Realtek linux nic maintainers , "netdev@vger.kernel.org" Subject: Re: [PATCH net-next] r8169: improve rtl8169_start_xmit Message-ID: <20201116075803.0a75fd3f@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <80085451-3eaf-507a-c7c0-08d607c46fbc@gmail.com> References: <80085451-3eaf-507a-c7c0-08d607c46fbc@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sat, 14 Nov 2020 21:49:53 +0100 Heiner Kallweit wrote: > Improve the following in rtl8169_start_xmit: > - tp->cur_tx can be accessed in parallel by rtl_tx(), therefore > annotate the race by using WRITE_ONCE > - avoid checking stop_queue a second time by moving the doorbell check > - netif_stop_queue() uses atomic operation set_bit() that includes a > full memory barrier on some platforms, therefore use > smp_mb__after_atomic to avoid overhead > > Signed-off-by: Heiner Kallweit Applied, thanks.