From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=37584 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pcmt1-0001Pu-5B for qemu-devel@nongnu.org; Tue, 11 Jan 2011 17:40:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Pcmsz-0002AR-5O for qemu-devel@nongnu.org; Tue, 11 Jan 2011 17:40:19 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58376) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Pcmsy-0002A5-R2 for qemu-devel@nongnu.org; Tue, 11 Jan 2011 17:40:17 -0500 Date: Wed, 12 Jan 2011 00:39:56 +0200 From: "Michael S. Tsirkin" Message-ID: <20110111223956.GA17227@redhat.com> References: <20110107220801.15395.38757.stgit@s20.home> <20110111213731.20822.21354.stgit@s20.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110111213731.20822.21354.stgit@s20.home> Subject: [Qemu-devel] Re: [PATCH v5] savevm: Fix no_migrate List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alex Williamson Cc: jan.kiszka@web.de, qemu-devel@nongnu.org, quintela@redhat.com On Tue, Jan 11, 2011 at 02:39:43PM -0700, Alex Williamson wrote: > The no_migrate save state flag is currently only checked in the > last phase of migration. This means that we potentially waste > a lot of time and bandwidth with the live state handlers before > we ever check the no_migrate flags. The error message printed > when we catch a non-migratable device doesn't get printed for > a detached migration. And, no_migrate does nothing to prevent > an incoming migration to a target that includes a non-migratable > device. This attempts to fix all of these. > > One notable difference in behavior is that an outgoing migration > now checks for non-migratable devices before ever connecting to > the target system. This means the target will remain listening > rather than exit from failure. > > Signed-off-by: Alex Williamson Acked-by: Michael S. Tsirkin > --- > > v5: > - change qemu_savevm_state_blocked() to return bool > - Daniel confirmed libvirt will not have a problem with the behavior > change on the target end. > > migration.c | 4 ++++ > savevm.c | 40 ++++++++++++++++++++++++++-------------- > sysemu.h | 1 + > 3 files changed, 31 insertions(+), 14 deletions(-) > > diff --git a/migration.c b/migration.c > index e5ba51c..d593b1d 100644 > --- a/migration.c > +++ b/migration.c > @@ -88,6 +88,10 @@ int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data) > return -1; > } > > + if (qemu_savevm_state_blocked(mon)) { > + return -1; > + } > + > if (strstart(uri, "tcp:", &p)) { > s = tcp_start_outgoing_migration(mon, p, max_throttle, detach, > blk, inc); > diff --git a/savevm.c b/savevm.c > index 90aa237..fcd8db4 100644 > --- a/savevm.c > +++ b/savevm.c > @@ -1401,19 +1401,13 @@ static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id) > return vmstate_load_state(f, se->vmsd, se->opaque, version_id); > } > > -static int vmstate_save(QEMUFile *f, SaveStateEntry *se) > +static void vmstate_save(QEMUFile *f, SaveStateEntry *se) > { > - if (se->no_migrate) { > - return -1; > - } > - > if (!se->vmsd) { /* Old style */ > se->save_state(f, se->opaque); > - return 0; > + return; > } > vmstate_save_state(f,se->vmsd, se->opaque); > - > - return 0; > } > > #define QEMU_VM_FILE_MAGIC 0x5145564d > @@ -1427,6 +1421,20 @@ static int vmstate_save(QEMUFile *f, SaveStateEntry *se) > #define QEMU_VM_SECTION_FULL 0x04 > #define QEMU_VM_SUBSECTION 0x05 > > +bool qemu_savevm_state_blocked(Monitor *mon) > +{ > + SaveStateEntry *se; > + > + QTAILQ_FOREACH(se, &savevm_handlers, entry) { > + if (se->no_migrate) { > + monitor_printf(mon, "state blocked by non-migratable device '%s'\n", > + se->idstr); > + return true; > + } > + } > + return false; > +} > + > int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable, > int shared) > { > @@ -1508,7 +1516,6 @@ int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f) > int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f) > { > SaveStateEntry *se; > - int r; > > cpu_synchronize_all_states(); > > @@ -1541,11 +1548,7 @@ int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f) > qemu_put_be32(f, se->instance_id); > qemu_put_be32(f, se->version_id); > > - r = vmstate_save(f, se); > - if (r < 0) { > - monitor_printf(mon, "cannot migrate with device '%s'\n", se->idstr); > - return r; > - } > + vmstate_save(f, se); > } > > qemu_put_byte(f, QEMU_VM_EOF); > @@ -1575,6 +1578,11 @@ static int qemu_savevm_state(Monitor *mon, QEMUFile *f) > saved_vm_running = vm_running; > vm_stop(0); > > + if (qemu_savevm_state_blocked(mon)) { > + ret = -EINVAL; > + goto out; > + } > + > ret = qemu_savevm_state_begin(mon, f, 0, 0); > if (ret < 0) > goto out; > @@ -1692,6 +1700,10 @@ int qemu_loadvm_state(QEMUFile *f) > unsigned int v; > int ret; > > + if (qemu_savevm_state_blocked(default_mon)) { > + return -EINVAL; > + } > + > v = qemu_get_be32(f); > if (v != QEMU_VM_FILE_MAGIC) > return -EINVAL; > diff --git a/sysemu.h b/sysemu.h > index d8fceec..0c969f2 100644 > --- a/sysemu.h > +++ b/sysemu.h > @@ -75,6 +75,7 @@ void qemu_announce_self(void); > > void main_loop_wait(int nonblocking); > > +bool qemu_savevm_state_blocked(Monitor *mon); > int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable, > int shared); > int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f);