From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58815) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d0KEU-0000NF-W5 for qemu-devel@nongnu.org; Mon, 17 Apr 2017 23:55:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d0KER-0001l1-Td for qemu-devel@nongnu.org; Mon, 17 Apr 2017 23:55:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60888) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d0KER-0001kf-Jm for qemu-devel@nongnu.org; Mon, 17 Apr 2017 23:55:11 -0400 References: <1487734936-43472-1-git-send-email-zhang.zhanghailiang@huawei.com> <1487734936-43472-3-git-send-email-zhang.zhanghailiang@huawei.com> <134776c2-a85d-d06f-5f98-2e664f9c8ca9@cn.fujitsu.com> <58F06AA1.2010301@huawei.com> <9b42232a-e86f-2d61-7987-7a0559d6f705@redhat.com> <58F4A12C.5070404@huawei.com> From: Jason Wang Message-ID: Date: Tue, 18 Apr 2017 11:55:03 +0800 MIME-Version: 1.0 In-Reply-To: <58F4A12C.5070404@huawei.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 02/15] colo-compare: implement the process of checkpoint List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Hailiang Zhang , Zhang Chen , qemu-devel@nongnu.org Cc: xuquan8@huawei.com, xiecl.fnst@cn.fujitsu.com, dgilbert@redhat.com, lizhijian@cn.fujitsu.com On 2017=E5=B9=B404=E6=9C=8817=E6=97=A5 19:04, Hailiang Zhang wrote: > Hi Jason, > > On 2017/4/14 14:38, Jason Wang wrote: >> >> On 2017=E5=B9=B404=E6=9C=8814=E6=97=A5 14:22, Hailiang Zhang wrote: >>> Hi Jason, >>> >>> On 2017/4/14 13:57, Jason Wang wrote: >>>> On 2017=E5=B9=B402=E6=9C=8822=E6=97=A5 17:31, Zhang Chen wrote: >>>>> On 02/22/2017 11:42 AM, zhanghailiang wrote: >>>>>> While do checkpoint, we need to flush all the unhandled packets, >>>>>> By using the filter notifier mechanism, we can easily to notify >>>>>> every compare object to do this process, which runs inside >>>>>> of compare threads as a coroutine. >>>>> Hi~ Jason and Hailiang. >>>>> >>>>> I will send a patch set later about colo-compare notify mechanism f= or >>>>> Xen like this patch. >>>>> I want to add a new chardev socket way in colo-comapre connect to X= en >>>>> colo, for notify >>>>> checkpoint or failover, Because We have no choice to use this way >>>>> communicate with Xen codes. >>>>> That's means we will have two notify mechanism. >>>>> What do you think about this? >>>>> >>>>> >>>>> Thanks >>>>> Zhang Chen >>>> I was thinking the possibility of using similar way to for colo=20 >>>> compare. >>>> E.g can we use socket? This can saves duplicated codes more or less. >>> Since there are too many sockets used by filter and COLO, (Two unix >>> sockets and two >>> tcp sockets for each vNIC), I don't want to introduce more ;) , but >>> i'm not sure if it is >>> possible to make it more flexible and optional, abstract these >>> duplicated codes, >>> pass the opened fd (No matter eventfd or socket fd ) as parameter, fo= r >>> example. >>> Is this way acceptable ? >>> >>> Thanks, >>> Hailiang >> Yes, that's kind of what I want. We don't want to use two message >> format. Passing a opened fd need management support, we still need a >> fallback if there's no management on top. For qemu/kvm, we can do all >> stuffs transparent to the cli by e.g socketpair() or others, but the k= ey >> is to have a unified message format. > > After a deeper investigation, i think we can re-use most codes, since=20 > there is no > existing way to notify xen (no ?), we still needs notify chardev=20 > socket (Be used to notify xen, it is optional.) > (http://patchwork.ozlabs.org/patch/733431/ "COLO-compare: Add Xen=20 > notify chardev socket handler frame") Yes and actually you can use this for bi-directional communication. The=20 only differences is the implementation of comparing. > > Besides, there is an existing qmp comand 'xen-colo-do-checkpoint',=20 I don't see this in master? > we can re-use it to notify > colo-compare objects and other filter objects to do checkpoint, for=20 > the opposite direction, we use > the notify chardev socket (Only for xen). Just want to make sure I understand the design, who will trigger this=20 command? Management? Can we just use the socket? > > So the codes will be like: > diff --git a/migration/colo.c b/migration/colo.c > index 91da936..813c281 100644 > --- a/migration/colo.c > +++ b/migration/colo.c > @@ -224,7 +224,19 @@ ReplicationStatus=20 > *qmp_query_xen_replication_status(Error **errp) > > void qmp_xen_colo_do_checkpoint(Error **errp) > { > + Error *local_err =3D NULL; > + > replication_do_checkpoint_all(errp); > + /* Notify colo-compare and other filters to do checkpoint */ > + colo_notify_compares_event(NULL, COLO_CHECKPOINT, &local_err); > + if (local_err) { > + error_propagate(errp, local_err); > + return; > + } > + colo_notify_filters_event(COLO_CHECKPOINT, &local_err); > + if (local_err) { > + error_propagate(errp, local_err); > + } > } > > static void colo_send_message(QEMUFile *f, COLOMessage msg, > diff --git a/net/colo-compare.c b/net/colo-compare.c > index 24e13f0..de975c5 100644 > --- a/net/colo-compare.c > +++ b/net/colo-compare.c > @@ -391,6 +391,9 @@ static void colo_compare_inconsistent_notify(void) > { > notifier_list_notify(&colo_compare_notifiers, > migrate_get_current()); > + if (s->notify_dev) { > + /* Do something, notify remote side through notify dev */ > + } > } > > void colo_compare_register_notifier(Notifier *notify) > > How about this scenario =EF=BC=9F See my reply above, and we need unify the message format too. Raw string=20 is ok but we'd better have something like TLV or others. Thanks > >> Thoughts? >> >> Thanks >> >>>> Thanks >>>> >>>> >>>> . >>>> >>> >> >> . >> > > >