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=-16.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 40F12C433B4 for ; Tue, 11 May 2021 15:22:23 +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 A129761182 for ; Tue, 11 May 2021 15:22:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A129761182 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]:56778 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lgUDF-0004YX-IB for qemu-devel@archiver.kernel.org; Tue, 11 May 2021 11:22:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55956) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lgU18-0007aS-HN for qemu-devel@nongnu.org; Tue, 11 May 2021 11:09:50 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:27010) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lgU16-0004YZ-69 for qemu-devel@nongnu.org; Tue, 11 May 2021 11:09:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1620745786; 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=kut2k8AQFD2uy14NKFAlyp3n85fRNitFkihyuY071Hg=; b=QGO02i1pm5u9RKsR7XDWtAIo6fpDar/PxhmnkWowPcMJHWCk9Ta3MTdobyU93g+Dh+u5rY k0CGNVcXLcPzjEN1q7gRGG2S5OemIPDbkP7Kt4UDOg3uBC46oi4tTjd9DwhNezRUbs5JLX 6TECHe+W5iGvT4bJuREeynkWCpWpwWs= 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-580-u4od1QOEPR2nU9TRUEdsSw-1; Tue, 11 May 2021 11:09:44 -0400 X-MC-Unique: u4od1QOEPR2nU9TRUEdsSw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5F32A1006C83; Tue, 11 May 2021 15:09:43 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-113-51.ams2.redhat.com [10.36.113.51]) by smtp.corp.redhat.com (Postfix) with ESMTP id BC9A7648A0; Tue, 11 May 2021 15:09:41 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, david@redhat.com, zhukeqian1@huawei.com, jiangkunkun@huawei.com, armbru@redhat.com, peter.maydell@linaro.org, huangy81@chinatelecom.cn Subject: [PULL 10/17] migration/ram: Discard RAM when growing RAM blocks after ram_postcopy_incoming_init() Date: Tue, 11 May 2021 16:08:35 +0100 Message-Id: <20210511150842.207155-11-dgilbert@redhat.com> In-Reply-To: <20210511150842.207155-1-dgilbert@redhat.com> References: <20210511150842.207155-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@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=170.10.133.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.699, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peterx@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: David Hildenbrand In case we grow our RAM after ram_postcopy_incoming_init() (e.g., when synchronizing the RAM block state with the migration source), the resized part would not get discarded. Let's perform that when being notified about a resize while postcopy has been advised, but is not listening yet. With precopy, the process is as following: 1. VM created - RAM blocks are created 2. Incomming migration started - Postcopy is advised - All pages in RAM blocks are discarded 3. Precopy starts - RAM blocks are resized to match the size on the migration source. - RAM pages from precopy stream are loaded - Uffd handler is registered, postcopy starts listening 4. Guest started, postcopy running - Pagefaults get resolved, pages get placed Reviewed-by: Peter Xu Signed-off-by: David Hildenbrand Message-Id: <20210429112708.12291-7-david@redhat.com> Signed-off-by: Dr. David Alan Gilbert --- migration/ram.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/migration/ram.c b/migration/ram.c index 77922c445e..e1d081d334 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -4099,6 +4099,7 @@ static SaveVMHandlers savevm_ram_handlers = { static void ram_mig_ram_block_resized(RAMBlockNotifier *n, void *host, size_t old_size, size_t new_size) { + PostcopyState ps = postcopy_state_get(); ram_addr_t offset; RAMBlock *rb = qemu_ram_block_from_host(host, false, &offset); Error *err = NULL; @@ -4119,6 +4120,35 @@ static void ram_mig_ram_block_resized(RAMBlockNotifier *n, void *host, error_free(err); migration_cancel(); } + + switch (ps) { + case POSTCOPY_INCOMING_ADVISE: + /* + * Update what ram_postcopy_incoming_init()->init_range() does at the + * time postcopy was advised. Syncing RAM blocks with the source will + * result in RAM resizes. + */ + if (old_size < new_size) { + if (ram_discard_range(rb->idstr, old_size, new_size - old_size)) { + error_report("RAM block '%s' discard of resized RAM failed", + rb->idstr); + } + } + break; + case POSTCOPY_INCOMING_NONE: + case POSTCOPY_INCOMING_RUNNING: + case POSTCOPY_INCOMING_END: + /* + * Once our guest is running, postcopy does no longer care about + * resizes. When growing, the new memory was not available on the + * source, no handler needed. + */ + break; + default: + error_report("RAM block '%s' resized during postcopy state: %d", + rb->idstr, ps); + exit(-1); + } } static RAMBlockNotifier ram_mig_ram_notifier = { -- 2.31.1