* Markus Armbruster (arm...@redhat.com) wrote:
> "Dr. David Alan Gilbert (git)" <dgilb...@redhat.com> writes:
>
> > From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
> >
> > -incoming defer causes qemu to wait for an incoming migration
> > to be specified later. The monitor can be used to set migration
> > capabilities that may affect the incoming connection process.
> >
> > Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> > Reviewed-by: Juan Quintela <quint...@redhat.com>
> > ---
> > migration/migration.c | 29 +++++++++++++++++++++++------
> > 1 file changed, 23 insertions(+), 6 deletions(-)
> >
> > diff --git a/migration/migration.c b/migration/migration.c
> > index b3adbc6..f3d49d5 100644
> > --- a/migration/migration.c
> > +++ b/migration/migration.c
> > @@ -49,6 +49,8 @@ enum {
> > static NotifierList migration_state_notifiers =
> > NOTIFIER_LIST_INITIALIZER(migration_state_notifiers);
> >
> > +static bool deferred_incoming;
> > +
> > /* When we add fault tolerance, we could have several
> > migrations at once. For now we don't need to add
> > dynamic creation of migration */
> > @@ -65,25 +67,40 @@ MigrationState *migrate_get_current(void)
> > return ¤t_migration;
> > }
> >
> > +/*
> > + * Called on -incoming with a defer: uri.
>
> The colon in "defer:" is inaccurate, because...
True, but probably not worth the respin.
> > + * The migration can be started later after any parameters have been
> > + * changed.
> > + */
> > +static void deferred_incoming_migration(Error **errp)
> > +{
> > + if (deferred_incoming) {
> > + error_setg(errp, "Incoming migration already deferred");
> > + }
> > + deferred_incoming = true;
> > +}
> > +
> > void qemu_start_incoming_migration(const char *uri, Error **errp)
> > {
> > const char *p;
> >
> > - if (strstart(uri, "tcp:", &p))
> > + if (!strcmp(uri, "defer")) {
>
> ... you recognize exactly "defer" here. <pedantic>Which makes it not an
> URI</pedantic>.
>
> > + deferred_incoming_migration(errp);
> > + } else if (strstart(uri, "tcp:", &p)) {
> > tcp_start_incoming_migration(p, errp);
> > #ifdef CONFIG_RDMA
> > - else if (strstart(uri, "rdma:", &p))
> > + } else if (strstart(uri, "rdma:", &p)) {
> > rdma_start_incoming_migration(p, errp);
> > #endif
> > #if !defined(WIN32)
> > - else if (strstart(uri, "exec:", &p))
> > + } else if (strstart(uri, "exec:", &p)) {
> > exec_start_incoming_migration(p, errp);
> > - else if (strstart(uri, "unix:", &p))
> > + } else if (strstart(uri, "unix:", &p)) {
> > unix_start_incoming_migration(p, errp);
> > - else if (strstart(uri, "fd:", &p))
> > + } else if (strstart(uri, "fd:", &p)) {
> > fd_start_incoming_migration(p, errp);
> > #endif
> > - else {
> > + } else {
> > error_setg(errp, "unknown migration protocol: %s", uri);
> > }
> > }
>
> How did you test the new error?
>
> I tried, but ran into this preexisting bug:
>
> $ qemu-system-x86_64 -nodefaults -S -display none -incoming defer
> -incoming defer
> ERROR: invalid runstate transition: 'inmigrate' -> 'inmigrate'
> Aborted (core dumped)
Fun; yes that's an existing bug that triggers with -incoming tcp::4444
-incoming tcp::4445
I'll think about that separately.
The way I tested the error was like this:
$ bin/qemu-system-x86_64 -nographic -incoming defer
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) migrate_incoming defer
Incoming migration already deferred
(qemu)
> In my opinion, multiple -incoming should behave like command line
> options usually do: last one wins silently.
Either that or error; to me this feels like it should probably
error; I'd make the distinction between options that set a value
(which works as a last one wins), or options that invoke an action,
for options that invoke an action it feels wrong to me to allow
incompatible options.
Dave
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
