From nobody Thu Nov 28 10:59:39 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1692969873; cv=none; d=zohomail.com; s=zohoarc; b=knCTel/QsNPUu4C6f9PZ8K1tahEA1hVQUg4jTUifiWwPNcdPjouN/KybVkTuG+uqM3m2APTf6HsOZiRhXPqiFYqTbKN+KXKxLUnSW4RV2FaeMwODYFe8juu1CKJ1nTT1Lh0dFtb13nVbzxXzhObxovXWpzD9yeLMv47lbi44JeA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1692969873; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=XtUWiTxvfEaXjj5InMUTbpkzC5jsR7h9EO68NccA5RQ=; b=IlSUhDGf6WWk11HbRu28gcR2HR5GLGl9izLnb71RhomnOxp7vo2lzFN2yEy8O+f4bzEm0AfRlKq95h6+Ya1ZhzRH/upx2SFOAlTuS3GdA70WyCzBNVTobwNCrB1HK8W3CzgUrHQAEl8Qdy1AVfrYRpQL2iWqZl7dmMdDHoDU9+4= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1692969872997420.5497598780885; Fri, 25 Aug 2023 06:24:32 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qZWmE-00020v-GW; Fri, 25 Aug 2023 09:23:02 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qZWmC-0001xL-Ib for qemu-devel@nongnu.org; Fri, 25 Aug 2023 09:23:00 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qZWmA-0001qW-GK for qemu-devel@nongnu.org; Fri, 25 Aug 2023 09:23:00 -0400 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-605-b24xiUr_P_OMUhSaKekaKA-1; Fri, 25 Aug 2023 09:22:54 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1B6E3856F67; Fri, 25 Aug 2023 13:22:54 +0000 (UTC) Received: from t14s.fritz.box (unknown [10.39.193.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 16DE5140E950; Fri, 25 Aug 2023 13:22:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1692969777; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=XtUWiTxvfEaXjj5InMUTbpkzC5jsR7h9EO68NccA5RQ=; b=VhI5Dd+F3RaejNGFiC+Ibco+WyRdPUR/64fOYJZlR3Bb1/TfZypBVlFw56LzHDoD6/dMPV S3wWAxy5zhd1PxYHA/uVEJJcRob3iBYhawFn8Iqd6XJp+ASjW26fKYmgXOR3qhb3y+GScu IAVKO3sAbUuTWJShEG3EFwAmeU17T+U= X-MC-Unique: b24xiUr_P_OMUhSaKekaKA-1 From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , Paolo Bonzini , Igor Mammedov , Xiao Guangrong , "Michael S. Tsirkin" , Peter Xu , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Eduardo Habkost , Marcel Apfelbaum , Yanan Wang , Michal Privoznik , =?UTF-8?q?Daniel=20P=20=2E=20Berrang=C3=A9?= , Gavin Shan , Alex Williamson , Stefan Hajnoczi , "Maciej S . Szmigiero" , kvm@vger.kernel.org Subject: [PATCH v2 16/16] virtio-mem: Mark memslot alias memory regions unmergeable Date: Fri, 25 Aug 2023 15:21:49 +0200 Message-ID: <20230825132149.366064-17-david@redhat.com> In-Reply-To: <20230825132149.366064-1-david@redhat.com> References: <20230825132149.366064-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1692969874824100003 Content-Type: text/plain; charset="utf-8" Let's mark the memslot alias memory regions as unmergable, such that flatview and vhost won't merge adjacent memory region aliases and we can atomically map/unmap individual aliases without affecting adjacent alias memory regions. This handles vhost and vfio in multiple-memslot mode correctly (which do not support atomic memslot updates) and avoids the temporary removal of large memslots, which can be an expensive operation. For example, vfio might have to unpin + repin a lot of memory, which is undesired. Signed-off-by: David Hildenbrand Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- hw/virtio/virtio-mem.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 724fcb189a..50770b577a 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -959,6 +959,12 @@ static void virtio_mem_prepare_memslots(VirtIOMEM *vme= m) memory_region_init_alias(&vmem->memslots[idx], OBJECT(vmem), name, &vmem->memdev->mr, memslot_offset, memslot_size); + /* + * We want to be able to atomically and efficiently activate/deact= ivate + * individual memslots without affecting adjacent memslots in memo= ry + * notifiers. + */ + memory_region_set_unmergeable(&vmem->memslots[idx], true); } } =20 --=20 2.41.0