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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 03237C4360C for ; Tue, 8 Oct 2019 19:07:25 +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 CBD572070B for ; Tue, 8 Oct 2019 19:07:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CBD572070B 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]:33590 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iHupP-0000OQ-Ux for qemu-devel@archiver.kernel.org; Tue, 08 Oct 2019 15:07:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43419) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iHuoF-0007ug-5c for qemu-devel@nongnu.org; Tue, 08 Oct 2019 15:06:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iHuoD-0002ai-AA for qemu-devel@nongnu.org; Tue, 08 Oct 2019 15:06:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51242) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iHuoD-0002aM-4O for qemu-devel@nongnu.org; Tue, 08 Oct 2019 15:06:09 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 23A664E83E; Tue, 8 Oct 2019 19:06:08 +0000 (UTC) Received: from work-vm (ovpn-116-59.ams2.redhat.com [10.36.116.59]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2EA1160BE2; Tue, 8 Oct 2019 19:06:06 +0000 (UTC) Date: Tue, 8 Oct 2019 20:06:04 +0100 From: "Dr. David Alan Gilbert" To: Wei Yang Subject: Re: [PATCH 2/3] migration/postcopy: postpone setting PostcopyState to END Message-ID: <20191008190604.GM3441@work-vm> References: <20191006000249.29926-1-richardw.yang@linux.intel.com> <20191006000249.29926-3-richardw.yang@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191006000249.29926-3-richardw.yang@linux.intel.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 08 Oct 2019 19:06:08 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 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: qemu-devel@nongnu.org, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Wei Yang (richardw.yang@linux.intel.com) wrote: > There are two places to call function postcopy_ram_incoming_cleanup() > > postcopy_ram_listen_thread on migration success > loadvm_postcopy_handle_listen one setup failure > > On success, the vm will never accept another migration. On failure, > PostcopyState is transited from LISTENING to END and would be checked in > qemu_loadvm_state_main(). If PostcopyState is RUNNING, migration would > be paused and retried. > > Currently PostcopyState is set to END in function > postcopy_ram_incoming_cleanup(). With above analysis, we can take this > step out and postpone this till the end of listen thread to indicate the > listen thread is done. > > This is a preparation patch for later cleanup. > > Signed-off-by: Wei Yang Yes, I think that's OK - I couldn't see anywhere that's currently checking the state in between. Reviewed-by: Dr. David Alan Gilbert > --- > migration/postcopy-ram.c | 2 -- > migration/savevm.c | 2 ++ > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c > index a394c7c3a6..5da6de8c8b 100644 > --- a/migration/postcopy-ram.c > +++ b/migration/postcopy-ram.c > @@ -577,8 +577,6 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis) > } > } > > - postcopy_state_set(POSTCOPY_INCOMING_END, NULL); > - > if (mis->postcopy_tmp_page) { > munmap(mis->postcopy_tmp_page, mis->largest_page_size); > mis->postcopy_tmp_page = NULL; > diff --git a/migration/savevm.c b/migration/savevm.c > index eaa4cf58ef..dcad8897a3 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -1837,6 +1837,8 @@ static void *postcopy_ram_listen_thread(void *opaque) > > rcu_unregister_thread(); > mis->have_listen_thread = false; > + postcopy_state_set(POSTCOPY_INCOMING_END, NULL); > + > return NULL; > } > > -- > 2.17.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK