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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 6D4AAC4361B for ; Tue, 8 Dec 2020 17:04:51 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D8B7423B00 for ; Tue, 8 Dec 2020 17:04:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D8B7423B00 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:60732 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kmgPx-0004A1-Hk for qemu-devel@archiver.kernel.org; Tue, 08 Dec 2020 12:04:49 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:37494) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kmg3B-0005s8-SB for qemu-devel@nongnu.org; Tue, 08 Dec 2020 11:41:17 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:25234) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kmg35-0005Uh-SK for qemu-devel@nongnu.org; Tue, 08 Dec 2020 11:41:17 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1607445670; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qfGCWQUsVRDvTQCbbBZJ06I0LBuOMnjVOrqrwhzY7wc=; b=CHFVxVu7XqjArJRVu+QXSBAx1wODqLuVv1fohrtiJwhbJYG5I8BttNJZCPzbNLtOMNbiTK zf8AbLsE/FxYIL5LycRAWz2H5gtY8HT1Iqxn7YQJ6eCx4TTJfZkCwZSaDjmd6nFiqjY1Bb hBSOoRG0JuDxoKcilUyyNR85X8F6Om4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-221-cEcZ1e5VOkCvfBQY6deCKw-1; Tue, 08 Dec 2020 11:41:07 -0500 X-MC-Unique: cEcZ1e5VOkCvfBQY6deCKw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BC85019611D0; Tue, 8 Dec 2020 16:40:24 +0000 (UTC) Received: from t480s.redhat.com (ovpn-113-236.ams2.redhat.com [10.36.113.236]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0DA8C5D6AB; Tue, 8 Dec 2020 16:40:21 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v2 10/10] vfio: Disable only uncoordinated discards Date: Tue, 8 Dec 2020 17:39:50 +0100 Message-Id: <20201208163950.29617-11-david@redhat.com> In-Reply-To: <20201208163950.29617-1-david@redhat.com> References: <20201208163950.29617-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=216.205.24.124; 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_H3=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , Wei Yang , David Hildenbrand , "Michael S. Tsirkin" , "Dr . David Alan Gilbert" , Peter Xu , Marek Kedzierski , Auger Eric , Alex Williamson , teawater , Jonathan Cameron , Paolo Bonzini , Igor Mammedov Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" We support coordinated discarding of RAM using the RamDiscardMgr. Let's unlock support for coordinated discards, keeping uncoordinated discards (e.g., via virtio-balloon) disabled. This unlocks virtio-mem + vfio. Note that vfio used via "nvme://" by the block layer has to be implemented/unlocked separately. For now, virtio-mem only supports x86-64 - spapr IOMMUs are not tested/affected. Note: The block size of a virtio-mem device has to be set to sane sizes, depending on the maximum hotplug size - to not run out of vfio mappings. The default virtio-mem block size is usually in the range of a couple of MBs. The maximum number of mapping is 64k, shared with other users. Assume you want to hotplug 256GB using virtio-mem - the block size would have to be set to at least 8 MiB (resulting in 32768 separate mappings). Cc: Paolo Bonzini Cc: "Michael S. Tsirkin" Cc: Alex Williamson Cc: Dr. David Alan Gilbert Cc: Igor Mammedov Cc: Pankaj Gupta Cc: Peter Xu Cc: Auger Eric Cc: Wei Yang Cc: teawater Cc: Marek Kedzierski Signed-off-by: David Hildenbrand --- hw/vfio/common.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 57c83a2f14..3ce5e26bab 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -1974,8 +1974,10 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as, * new memory, it will not yet set ram_block_discard_set_required() and * therefore, neither stops us here or deals with the sudden memory * consumption of inflated memory. + * + * We do support discarding of memory coordinated via the RamDiscardMgr. */ - ret = ram_block_discard_disable(true); + ret = ram_block_uncoordinated_discard_disable(true); if (ret) { error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken"); return ret; @@ -2155,7 +2157,7 @@ close_fd_exit: close(fd); put_space_exit: - ram_block_discard_disable(false); + ram_block_uncoordinated_discard_disable(false); vfio_put_address_space(space); return ret; @@ -2277,7 +2279,7 @@ void vfio_put_group(VFIOGroup *group) } if (!group->ram_block_discard_allowed) { - ram_block_discard_disable(false); + ram_block_uncoordinated_discard_disable(false); } vfio_kvm_device_del_group(group); vfio_disconnect_container(group); @@ -2331,7 +2333,7 @@ int vfio_get_device(VFIOGroup *group, const char *name, if (!group->ram_block_discard_allowed) { group->ram_block_discard_allowed = true; - ram_block_discard_disable(false); + ram_block_uncoordinated_discard_disable(false); } } -- 2.28.0