From patchwork Thu Jan 5 12:45:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13089785 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.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 smtp.lore.kernel.org (Postfix) with ESMTPS id B925AC3DA7D for ; Thu, 5 Jan 2023 12:47:34 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pDPd3-0000Z7-CL; Thu, 05 Jan 2023 07:45:53 -0500 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 1pDPcm-0000Xw-JL for qemu-devel@nongnu.org; Thu, 05 Jan 2023 07:45:37 -0500 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 1pDPck-0005mW-9U for qemu-devel@nongnu.org; Thu, 05 Jan 2023 07:45:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1672922732; 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; bh=9kDadsZ1LNoRqVL49cb2BUn1zLt/cvXadLYhKXY9KHU=; b=Z4ZoXeQgUPrHnh9XsS62IxaKhQ36gqT/wvyyhMTFgiz3YWcKtlbq5NphVTSoOODuXiJ7Mb jUE08k/5PBMmoztyBiVW4afr6jP89XAd7LPzWgJ6O2Zl0hl3+W1GrDs7cnTdJq5aiNMpoL kyPSkoobtJ+SeDNF+Tk0QBIgJrQw6Ro= 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-477-471nLbFQNt6WqCoKHxEnbg-1; Thu, 05 Jan 2023 07:45:31 -0500 X-MC-Unique: 471nLbFQNt6WqCoKHxEnbg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id ECE7A8588E7; Thu, 5 Jan 2023 12:45:30 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.192.193]) by smtp.corp.redhat.com (Postfix) with ESMTP id 53A851121314; Thu, 5 Jan 2023 12:45:29 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , Juan Quintela , "Dr. David Alan Gilbert" , Peter Xu , Andrey Gruzdev Subject: [PATCH v1 0/5] migration/ram: background snapshot fixes and optimiations Date: Thu, 5 Jan 2023 13:45:23 +0100 Message-Id: <20230105124528.93813-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 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_H2=-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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Playing with background snapshots in combination with hugetlb and virtio-mem, I found two issues and some reasonable optimizations (skip unprotecting when unregistering). With virtio-mem (RamDiscardManager), we now won't be allocating unnecessary page tables for unplugged ranges when using uffd-wp with shmem/hugetlb. Cc: Juan Quintela (maintainer:Migration) Cc: "Dr. David Alan Gilbert" (maintainer:Migration) Cc: Peter Xu Cc: Andrey Gruzdev David Hildenbrand (5): migration/ram: Fix populate_read_range() migration/ram: Fix error handling in ram_write_tracking_start() migration/ram: Don't explicitly unprotect when unregistering uffd-wp migration/ram: Rely on used_length for uffd_change_protection() migration/ram: Optimize ram_write_tracking_start() for RamDiscardManager migration/ram.c | 54 ++++++++++++++++++++++++++++++++++++------------- 1 file changed, 40 insertions(+), 14 deletions(-) Acked-by: Peter Xu