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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9F9B9C8303C for ; Fri, 11 Jul 2025 07:41:31 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.1040593.1411990 (Exim 4.92) (envelope-from ) id 1ua8Nh-0001kg-6g; Fri, 11 Jul 2025 07:41:17 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 1040593.1411990; Fri, 11 Jul 2025 07:41:17 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1ua8Nh-0001kZ-43; Fri, 11 Jul 2025 07:41:17 +0000 Received: by outflank-mailman (input) for mailman id 1040593; Fri, 11 Jul 2025 07:41:15 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1ua8Nf-0001kS-N1 for xen-devel@lists.xenproject.org; Fri, 11 Jul 2025 07:41:15 +0000 Received: from mail179-35.suw41.mandrillapp.com (mail179-35.suw41.mandrillapp.com [198.2.179.35]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 655c82a9-5e2a-11f0-a318-13f23c93f187; Fri, 11 Jul 2025 09:41:03 +0200 (CEST) Received: from pmta12.mandrill.prod.suw01.rsglab.com (localhost [127.0.0.1]) by mail179-35.suw41.mandrillapp.com (Mailchimp) with ESMTP id 4bdkCy39MPzDRJnHS for ; Fri, 11 Jul 2025 07:41:02 +0000 (GMT) Received: from [37.26.189.201] by mandrillapp.com id c0c98627b45b480b8fbd2a839ca5d463; Fri, 11 Jul 2025 07:41:02 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 655c82a9-5e2a-11f0-a318-13f23c93f187 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mandrillapp.com; s=mte1; t=1752219662; x=1752489662; bh=HWTYzQJa/AfE0/PYzIww/Vdcho/R6E1wlPo0cGaFq1U=; h=From:Subject:To:Cc:Message-Id:References:In-Reply-To:Feedback-ID: Date:MIME-Version:Content-Type:Content-Transfer-Encoding:CC:Date: Subject:From; b=QTfSaoO6DXcrQnuP/vxhtAH+TT3dtX7qkNJ4jfhxtkJXioKIJDr/95xAVVRaTO500 gJtMmhTjKBqKKOHG20totsJ9Wai8NYsxJFeWeSGI70bpKINpwztOdIB1WnXQCN9iTJ PKG6+XBAam/Z1pHcjAEwE0Vox5gbXpcMTNWPXtvTFNK6l8wBojhIm/YCYbUCZQQOq+ ZTFN/lrjgmGvTerDDz7Ef3hy0Wm44SiaPk4seVM42kiVvXm/4VovDr6RBqjVZmsT1N c3eLJMfhphDtTa/9IBwEbeJgB8M3QqbdyJUoq9Ts/Rhpq5SZYP5AT1dEEvNZXpip4a 1wqdvlx+KuHoQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vates.tech; s=mte1; t=1752219662; x=1752480162; i=anthoine.bourgeois@vates.tech; bh=HWTYzQJa/AfE0/PYzIww/Vdcho/R6E1wlPo0cGaFq1U=; h=From:Subject:To:Cc:Message-Id:References:In-Reply-To:Feedback-ID: Date:MIME-Version:Content-Type:Content-Transfer-Encoding:CC:Date: Subject:From; b=RobnsXtAJOcQ+Mx2lNgcUINqdc9fy3iJLlL1EXzh24pU0Nk9x0AIn+OB6WSy9QLWM ljBX9Tz1qKUDVq3Yjz6h4OCyrtwiAOcIdc+i+PtpHatmzKtXRnZVnEaQPjOYmSOUEe BprBzj4gjE+ouj122RSbYCPNDHJyYk/nyHBptlvHS9SfIYm67yaXVPLGH3kD1BiXwP dp4jJ6YC3aR5SzDHjW0HrKFl69OtgYRDuouZIFdSpZk0lCKHi2P8smY2TCjfYttJtY PJEydk3IldbtP1D26/S6GfFEZtZXJGVRhWUnRkgoBDsrtpEM6HeB43pU4HPnu6yf6B Pil2rZART5LIA== From: "Anthoine Bourgeois" Subject: =?utf-8?Q?Re:=20[PATCH]=20xen/netfront:=20Fix=20TX=20response=20spurious=20interrupts?= X-Bm-Disclaimer: Yes X-Bm-Milter-Handled: 4ffbd6c1-ee69-4e1b-aabd-f977039bd3e2 X-Bm-Transport-Timestamp: 1752219661292 To: "Elliott Mitchell" Cc: xen-devel@lists.xenproject.org, "Juergen Gross" , "Stefano Stabellini" , "Oleksandr Tyshchenko" , "=?utf-8?Q?Roger=20Pau=20Monn=C3=A9?=" , "Andrei Semenov" Message-Id: References: <20250710161029.3773630-1-anthoine.bourgeois@vates.tech> In-Reply-To: X-Native-Encoded: 1 X-Report-Abuse: =?UTF-8?Q?Please=20forward=20a=20copy=20of=20this=20message,=20including=20all=20headers,=20to=20abuse@mandrill.com.=20You=20can=20also=20report=20abuse=20here:=20https://mandrillapp.com/contact/abuse=3Fid=3D30504962.c0c98627b45b480b8fbd2a839ca5d463?= X-Mandrill-User: md_30504962 Feedback-ID: 30504962:30504962.20250711:md Date: Fri, 11 Jul 2025 07:41:02 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit On Thu, Jul 10, 2025 at 01:05:47PM -0700, Elliott Mitchell wrote: >On Thu, Jul 10, 2025 at 04:11:15PM +0000, Anthoine Bourgeois wrote: >> We found at Vates that there are lot of spurious interrupts when >> benchmarking the PV drivers of Xen. This issue appeared with a patch >> that addresses security issue XSA-391 (see Fixes below). On an iperf >> benchmark, spurious interrupts can represent up to 50% of the >> interrupts. > >If this is the correct fix, near-identical fixes are needed for *all* >of the Xen front-ends. Xen virtual block-devices and Xen PCI-passthrough >devices are also effected by a similar issue. > blkfront doesn't call the response handle from multiple places. It doesn't seem to be affected by this problem. And pcifront neither. >Thanks for finding a candidate fix, this effects many other people who >have been troubled by this performance issue. > >FreeBSD will also need a similar fix. In FreeBSD, netfront may also be affected. xn_assemble_tx_request calls xn_txeof. blkfront and pcifront seems good. Regards, Anthoine Anthoine Bourgeois | Vates XCP-ng Developer XCP-ng & Xen Orchestra - Vates solutions web: https://vates.tech