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 C76BFC27C53 for ; Wed, 12 Jun 2024 08:31:21 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.738957.1145826 (Exim 4.92) (envelope-from ) id 1sHJNu-0006qq-74; Wed, 12 Jun 2024 08:31:10 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 738957.1145826; Wed, 12 Jun 2024 08:31:10 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sHJNu-0006qj-2X; Wed, 12 Jun 2024 08:31:10 +0000 Received: by outflank-mailman (input) for mailman id 738957; Wed, 12 Jun 2024 08:31:09 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sHJNt-0006q6-8Z for xen-devel@lists.xenproject.org; Wed, 12 Jun 2024 08:31:09 +0000 Received: from mail-wm1-x32e.google.com (mail-wm1-x32e.google.com [2a00:1450:4864:20::32e]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 1d7257fe-2896-11ef-b4bb-af5377834399; Wed, 12 Jun 2024 10:31:07 +0200 (CEST) Received: by mail-wm1-x32e.google.com with SMTP id 5b1f17b1804b1-421d32fda86so30369335e9.0 for ; Wed, 12 Jun 2024 01:31:07 -0700 (PDT) Received: from localhost ([213.195.124.163]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-422874de618sm16423335e9.37.2024.06.12.01.31.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Jun 2024 01:31:06 -0700 (PDT) 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: 1d7257fe-2896-11ef-b4bb-af5377834399 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.com; s=google; t=1718181067; x=1718785867; darn=lists.xenproject.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=8A0WhxCTC1sf7GsqpPCXviAZ1key9LA6PyIZaOL7QxA=; b=NrUFY9PcAjv6Oi12A62VUtZYCVbH8bf2Vw7DHXVylWjRa93gydBkQReSGRGp0kknQP bzNkjdBc1npUBAGWjd9Id99J71NVFHVz7yYzUbEzWmDrL7deHHDQZ93bwaegTeXQMbXa 4+AniWpyQ5fFe2RVz3sO9qcvZTo/Y9w8zA7hg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718181067; x=1718785867; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=8A0WhxCTC1sf7GsqpPCXviAZ1key9LA6PyIZaOL7QxA=; b=aZaFXq7NXstJfiJN8eF8GupVfYU3/sIhCAS/uIqp5/MdXCgCUkxvi1Da/zoogNuFM/ XXSkwilqjQggdiuTvNhJHYq1vV8YdNL6uPQaG/nkaVawGXUXBfjJ27hpqYmH6eDmmxSr vfJggM7S99rjCkIZFdiI8w62t/HqCUg8ZFAX0Vc1OcXPTOXVQDA0qJZ8pwPpdEdf2MwG MiE7fqRgcZU3ZOZ8BR7d2uOfxKdTxdiw6lF8sEKLC7zeocqvEK7G5+zOB8xyemGZHwEa 4djSFj3U1S45SpKTtRtfzRXiMou8m8DbTEFbd7DFiZ7MI5LNmHd/jM0ld6fOj5ra7pdw 8igQ== X-Forwarded-Encrypted: i=1; AJvYcCVjRnbibSvb0ILUJxQ4inu2dIIBN0L3eQdsAuOuvEMUxbZ7yhKlYw4qUUBzbztNjD18zIowb4u1npvJaN/27CC0h8F31rGzgd7kVRT5d88= X-Gm-Message-State: AOJu0YwIZ6p2Oz6HvK0QrMrCl3QkjZemT3Va3iE+ISuf8u8LZjs6Yedv EP277ewnhSnZJ6HUX3Y+jHo9JVqZsxj9DPsweAOAPNja5SbuyqagE3C93YB+MUg= X-Google-Smtp-Source: AGHT+IEuBdChjBDzysOORmqPbbCyzmTofVzaRyuyCob+e8MQ8OQyrPKu+c57GZbpSLh/BBAvqdcFaQ== X-Received: by 2002:a05:600c:46ce:b0:422:e8d:e559 with SMTP id 5b1f17b1804b1-422864aebe0mr12309155e9.23.1718181067152; Wed, 12 Jun 2024 01:31:07 -0700 (PDT) Date: Wed, 12 Jun 2024 10:31:06 +0200 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Jan Beulich Cc: Andrew Cooper , xen-devel@lists.xenproject.org Subject: Re: [PATCH v2 4/7] x86/irq: restrict CPU movement in set_desc_affinity() Message-ID: References: <20240610142043.11924-1-roger.pau@citrix.com> <20240610142043.11924-5-roger.pau@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Tue, Jun 11, 2024 at 12:20:33PM +0200, Jan Beulich wrote: > On 10.06.2024 16:20, Roger Pau Monne wrote: > > If external interrupts are using logical mode it's possible to have an overlap > > between the current ->arch.cpu_mask and the provided mask (or TARGET_CPUS). If > > that's the case avoid assigning a new vector and just move the interrupt to a > > member of ->arch.cpu_mask that overlaps with the provided mask and is online. > > What I'm kind of missing here is an explanation of why what _assign_irq_vector() > does to avoid unnecessary migration (very first conditional there) isn't > sufficient. Somehow I looked at that and think it wasn't enough, but now I cannot figure out why, so it might be just fine, and this patch is not needed. Let me test again and get back to you, for the time being ignore this patch. Thanks, Roger.