diff mbox series

[V1,1/3] migration: check mode in notifiers

Message ID 1702491093-383782-2-git-send-email-steven.sistare@oracle.com
State New
Headers show
Series allow cpr-reboot for vfio | expand

Commit Message

Steven Sistare Dec. 13, 2023, 6:11 p.m. UTC
The existing notifiers should only apply to normal mode.

No functional change.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
 hw/net/virtio-net.c      | 4 ++++
 hw/vfio/migration.c      | 3 +++
 include/migration/misc.h | 1 +
 migration/migration.c    | 5 +++++
 net/vhost-vdpa.c         | 4 ++++
 ui/spice-core.c          | 2 +-
 6 files changed, 18 insertions(+), 1 deletion(-)

Comments

Peter Xu Jan. 10, 2024, 7:09 a.m. UTC | #1
On Wed, Dec 13, 2023 at 10:11:31AM -0800, Steve Sistare wrote:
> The existing notifiers should only apply to normal mode.
> 
> No functional change.

Instead of adding such check in every notifier, why not make CPR a separate
list of notifiers?  Just like the blocker lists.

Aside of this patch, I just started to look at this "notifier" code, I
really don't think we should pass in MigrationState* into the notifiers.
IIUC we only need the "state" as an enum.  Then with two separate
registers, the device code knows the migration mode.

What do you think?
Steven Sistare Jan. 10, 2024, 6:08 p.m. UTC | #2
On 1/10/2024 2:09 AM, Peter Xu wrote:
> On Wed, Dec 13, 2023 at 10:11:31AM -0800, Steve Sistare wrote:
>> The existing notifiers should only apply to normal mode.
>>
>> No functional change.
> 
> Instead of adding such check in every notifier, why not make CPR a separate
> list of notifiers?  Just like the blocker lists.

Sure.   I proposed minimal changes in this current series, but extending the 
api to take migration mode would be nicer.

> Aside of this patch, I just started to look at this "notifier" code, I
> really don't think we should pass in MigrationState* into the notifiers.
> IIUC we only need the "state" as an enum.  Then with two separate
> registers, the device code knows the migration mode.
> 
> What do you think?

If we pass state, the notifier must either compare to enum values such as
MIGRATION_STATUS_COMPLETED instead of calling migration_has_finished(s), or
we must define new accessors such as migration_state_is_finished(state).

IMO passing MigrationState is the best approach.
MigrationState is an incomplete type in most notifiers, and the client can
pass it to a limited set of accessors to get more information -- exactly what 
we want to hide migration internals.  However, we could further limit the
allowed accessors, eg move these to a new file "include/migration/notifier.h".

----------------------------------------
#include "qemu/notify.h"
void migration_add_notifier(Notifier *notify,
                            void (*func)(Notifier *notifier, void *data));
void migration_remove_notifier(Notifier *notify);
bool migration_is_active(MigrationState *);
bool migration_in_setup(MigrationState *);
bool migration_has_finished(MigrationState *);
bool migration_has_failed(MigrationState *);
-----------------------------------------------

- Steve
Peter Xu Jan. 11, 2024, 1:45 a.m. UTC | #3
On Wed, Jan 10, 2024 at 01:08:01PM -0500, Steven Sistare wrote:
> On 1/10/2024 2:09 AM, Peter Xu wrote:
> > On Wed, Dec 13, 2023 at 10:11:31AM -0800, Steve Sistare wrote:
> >> The existing notifiers should only apply to normal mode.
> >>
> >> No functional change.
> > 
> > Instead of adding such check in every notifier, why not make CPR a separate
> > list of notifiers?  Just like the blocker lists.
> 
> Sure.   I proposed minimal changes in this current series, but extending the 
> api to take migration mode would be nicer.
> 
> > Aside of this patch, I just started to look at this "notifier" code, I
> > really don't think we should pass in MigrationState* into the notifiers.
> > IIUC we only need the "state" as an enum.  Then with two separate
> > registers, the device code knows the migration mode.
> > 
> > What do you think?
> 
> If we pass state, the notifier must either compare to enum values such as
> MIGRATION_STATUS_COMPLETED instead of calling migration_has_finished(s), or
> we must define new accessors such as migration_state_is_finished(state).
> 
> IMO passing MigrationState is the best approach.
> MigrationState is an incomplete type in most notifiers, and the client can
> pass it to a limited set of accessors to get more information -- exactly what 
> we want to hide migration internals.  However, we could further limit the
> allowed accessors, eg move these to a new file "include/migration/notifier.h".
> 
> ----------------------------------------
> #include "qemu/notify.h"
> void migration_add_notifier(Notifier *notify,
>                             void (*func)(Notifier *notifier, void *data));
> void migration_remove_notifier(Notifier *notify);
> bool migration_is_active(MigrationState *);
> bool migration_in_setup(MigrationState *);
> bool migration_has_finished(MigrationState *);
> bool migration_has_failed(MigrationState *);
> -----------------------------------------------

Yes this also sounds good.  Thanks,
diff mbox series

Patch

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 80c56f0..0fa083d 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -3532,6 +3532,10 @@  static void virtio_net_handle_migration_primary(VirtIONet *n, MigrationState *s)
 static void virtio_net_migration_state_notifier(Notifier *notifier, void *data)
 {
     MigrationState *s = data;
+
+    if (migrate_mode_of(s) != MIG_MODE_NORMAL) {
+        return;
+    }
     VirtIONet *n = container_of(notifier, VirtIONet, migration_state);
     virtio_net_handle_migration_primary(n, s);
 }
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index 28d422b..814132a 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -763,6 +763,9 @@  static void vfio_migration_state_notifier(Notifier *notifier, void *data)
                                             migration_state);
     VFIODevice *vbasedev = migration->vbasedev;
 
+    if (migrate_mode_of(s) != MIG_MODE_NORMAL) {
+        return;
+    }
     trace_vfio_migration_state_notifier(vbasedev->name,
                                         MigrationStatus_str(s->state));
 
diff --git a/include/migration/misc.h b/include/migration/misc.h
index 1bc8902..901d117 100644
--- a/include/migration/misc.h
+++ b/include/migration/misc.h
@@ -61,6 +61,7 @@  void migration_object_init(void);
 void migration_shutdown(void);
 bool migration_is_idle(void);
 bool migration_is_active(MigrationState *);
+MigMode migrate_mode_of(MigrationState *);
 void migration_add_notifier(Notifier *notify,
                             void (*func)(Notifier *notifier, void *data));
 void migration_remove_notifier(Notifier *notify);
diff --git a/migration/migration.c b/migration/migration.c
index 2cc7e2a..d5bfe70 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1559,6 +1559,11 @@  bool migration_is_active(MigrationState *s)
             s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE);
 }
 
+MigMode migrate_mode_of(MigrationState *s)
+{
+    return s->parameters.mode;
+}
+
 int migrate_init(MigrationState *s, Error **errp)
 {
     int ret;
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index d0614d7..80acc4b 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -336,6 +336,10 @@  static void vdpa_net_migration_state_notifier(Notifier *notifier, void *data)
     VhostVDPAState *s = container_of(notifier, VhostVDPAState,
                                      migration_state);
 
+    if (migrate_mode_of(migration) != MIG_MODE_NORMAL) {
+        return;
+    }
+
     if (migration_in_setup(migration)) {
         vhost_vdpa_net_log_global_enable(s, true);
     } else if (migration_has_failed(migration)) {
diff --git a/ui/spice-core.c b/ui/spice-core.c
index db21db2..0a04eb0 100644
--- a/ui/spice-core.c
+++ b/ui/spice-core.c
@@ -572,7 +572,7 @@  static void migration_state_notifier(Notifier *notifier, void *data)
 {
     MigrationState *s = data;
 
-    if (!spice_have_target_host) {
+    if (!spice_have_target_host || migrate_mode_of(s) != MIG_MODE_NORMAL) {
         return;
     }