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.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 70449C636D7 for ; Tue, 21 Feb 2023 23:21:14 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pUbw5-0002jT-Ip; Tue, 21 Feb 2023 18:20:37 -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 1pUbw2-0002hh-Nn for qemu-devel@nongnu.org; Tue, 21 Feb 2023 18:20:34 -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 1pUbw1-0001FL-6s for qemu-devel@nongnu.org; Tue, 21 Feb 2023 18:20:34 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1677021632; h=from:from:reply-to: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=aJnBi+G5xtHxPLpnu3pdd1PMYcXJMatoymCmVjBZB+U=; b=iaxZsZX5FM+U9QBTPwkhxDgm6PblbPMfRDDIxNw67JiAeAWSNj3qsXUKIx4SmcsMBlJGc8 C8fj4rSLfv1NmVXvtt2mJqdpqHPebyXmDywR6X1bbOdR6ADLRuo8LUew+9zJ5qF/k4KGCE XpTHU4ZL/2nmdkVJY6J1+1Wt3ZcAXoU= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-201-6vZV1wxqMFyple8InTK1Iw-1; Tue, 21 Feb 2023 18:20:29 -0500 X-MC-Unique: 6vZV1wxqMFyple8InTK1Iw-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8C10D1C0434A; Tue, 21 Feb 2023 23:20:28 +0000 (UTC) Received: from [10.72.12.31] (ovpn-12-31.pek2.redhat.com [10.72.12.31]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 16144492B04; Tue, 21 Feb 2023 23:20:17 +0000 (UTC) Subject: Re: [PATCH v1 2/6] migration: Add last stage indicator to global dirty log synchronization To: Peter Xu Cc: qemu-arm@nongnu.org, qemu-devel@nongnu.org, pbonzini@redhat.com, peter.maydell@linaro.org, david@redhat.com, philmd@linaro.org, mst@redhat.com, cohuck@redhat.com, quintela@redhat.com, dgilbert@redhat.com, maz@kernel.org, zhenyzha@redhat.com, shan.gavin@gmail.com References: <20230213003925.40158-1-gshan@redhat.com> <20230213003925.40158-3-gshan@redhat.com> From: Gavin Shan Message-ID: <9022bc0c-db3d-d8f2-4071-f3752c8ee1f0@redhat.com> Date: Wed, 22 Feb 2023 10:20:13 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.129.124; envelope-from=gshan@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 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, NICE_REPLY_A=-0.095, 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: , Reply-To: Gavin Shan Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 2/22/23 4:36 AM, Peter Xu wrote: > On Mon, Feb 13, 2023 at 08:39:21AM +0800, Gavin Shan wrote: >> The global dirty log synchronization is used when KVM and dirty ring >> are enabled. There is a particularity for ARM64 where the backup >> bitmap is used to track dirty pages in non-running-vcpu situations. >> It means the dirty ring works with the combination of ring buffer >> and backup bitmap. The dirty bits in the backup bitmap needs to >> collected in the last stage of live migration. >> >> In order to identify the last stage of live migration and pass it >> down, an extra parameter is added to the relevant functions and >> callbacks. This last stage indicator isn't used until the dirty >> ring is enabled in the subsequent patches. >> >> No functional change intended. >> >> Signed-off-by: Gavin Shan > > Reviewed-by: Peter Xu > > One trivial thing to mention below. > >> --- >> accel/kvm/kvm-all.c | 2 +- >> include/exec/memory.h | 5 +++-- >> migration/dirtyrate.c | 4 ++-- >> migration/ram.c | 20 ++++++++++---------- >> softmmu/memory.c | 10 +++++----- >> 5 files changed, 21 insertions(+), 20 deletions(-) >> >> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c >> index 9b26582655..01a6a026af 100644 >> --- a/accel/kvm/kvm-all.c >> +++ b/accel/kvm/kvm-all.c >> @@ -1554,7 +1554,7 @@ static void kvm_log_sync(MemoryListener *listener, >> kvm_slots_unlock(); >> } >> >> -static void kvm_log_sync_global(MemoryListener *l) >> +static void kvm_log_sync_global(MemoryListener *l, bool last_stage) >> { >> KVMMemoryListener *kml = container_of(l, KVMMemoryListener, listener); >> KVMState *s = kvm_state; >> diff --git a/include/exec/memory.h b/include/exec/memory.h >> index 2e602a2fad..75b2fd9f48 100644 >> --- a/include/exec/memory.h >> +++ b/include/exec/memory.h >> @@ -929,8 +929,9 @@ struct MemoryListener { >> * its @log_sync must be NULL. Vice versa. >> * >> * @listener: The #MemoryListener. >> + * @last_stage: The last stage to synchronize the log during migration > > IMHO it may be important to mention the vcpu status here that the caller > guarantees to call the last_stage==true only once, only after all vcpus are > stopped (and vcpus will not be started again if migration succeeded). > Yes, I will update the comments in next revision accordingly. >> */ >> - void (*log_sync_global)(MemoryListener *listener); >> + void (*log_sync_global)(MemoryListener *listener, bool last_stage); Thanks, Gavin