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[PATCH 2/3] migration: Inhibit virtio-balloon for the duration of background snapshot

Andrey Gruzdev posted 3 patches 4 years, 10 months ago
Maintainers: Juan Quintela <quintela@redhat.com>, David Hildenbrand <david@redhat.com>, "Dr. David Alan Gilbert" <dgilbert@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>
There is a newer version of this series
[PATCH 2/3] migration: Inhibit virtio-balloon for the duration of background snapshot
Posted by Andrey Gruzdev 4 years, 10 months ago 
The same thing as for incoming postcopy - we cannot deal with concurrent
RAM discards when using background snapshot feature in outgoing migration.

Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
---
 hw/virtio/virtio-balloon.c | 8 ++++++--
 include/migration/misc.h   | 2 ++
 migration/migration.c      | 8 ++++++++
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index e770955176..d120bf8f43 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -66,8 +66,12 @@ static bool virtio_balloon_pbp_matches(PartiallyBalloonedPage *pbp,
 
 static bool virtio_balloon_inhibited(void)
 {
-    /* Postcopy cannot deal with concurrent discards, so it's special. */
-    return ram_block_discard_is_disabled() || migration_in_incoming_postcopy();
+    /*
+     * Postcopy cannot deal with concurrent discards,
+     * so it's special, as well as background snapshots.
+     */
+    return ram_block_discard_is_disabled() || migration_in_incoming_postcopy() ||
+            migration_in_bg_snapshot();
 }
 
 static void balloon_inflate_page(VirtIOBalloon *balloon,
diff --git a/include/migration/misc.h b/include/migration/misc.h
index bccc1b6b44..738675ef52 100644
--- a/include/migration/misc.h
+++ b/include/migration/misc.h
@@ -70,6 +70,8 @@ bool migration_in_postcopy_after_devices(MigrationState *);
 void migration_global_dump(Monitor *mon);
 /* True if incomming migration entered POSTCOPY_INCOMING_DISCARD */
 bool migration_in_incoming_postcopy(void);
+/* True if background snapshot is active */
+bool migration_in_bg_snapshot(void);
 
 /* migration/block-dirty-bitmap.c */
 void dirty_bitmap_mig_init(void);
diff --git a/migration/migration.c b/migration/migration.c
index 496cf6e17b..656d6249a6 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1976,6 +1976,14 @@ bool migration_in_incoming_postcopy(void)
     return ps >= POSTCOPY_INCOMING_DISCARD && ps < POSTCOPY_INCOMING_END;
 }
 
+bool migration_in_bg_snapshot(void)
+{
+    MigrationState *s = migrate_get_current();
+
+    return migrate_background_snapshot() &&
+            migration_is_setup_or_active(s->state);
+}
+
 bool migration_is_idle(void)
 {
     MigrationState *s = current_migration;
-- 
2.25.1
Re: [PATCH 2/3] migration: Inhibit virtio-balloon for the duration of background snapshot
Posted by David Hildenbrand 4 years, 10 months ago 
On 18.03.21 18:46, Andrey Gruzdev wrote:
> The same thing as for incoming postcopy - we cannot deal with concurrent
> RAM discards when using background snapshot feature in outgoing migration.
> 
> Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
> ---
>   hw/virtio/virtio-balloon.c | 8 ++++++--
>   include/migration/misc.h   | 2 ++
>   migration/migration.c      | 8 ++++++++
>   3 files changed, 16 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
> index e770955176..d120bf8f43 100644
> --- a/hw/virtio/virtio-balloon.c
> +++ b/hw/virtio/virtio-balloon.c
> @@ -66,8 +66,12 @@ static bool virtio_balloon_pbp_matches(PartiallyBalloonedPage *pbp,
>   
>   static bool virtio_balloon_inhibited(void)
>   {
> -    /* Postcopy cannot deal with concurrent discards, so it's special. */
> -    return ram_block_discard_is_disabled() || migration_in_incoming_postcopy();
> +    /*
> +     * Postcopy cannot deal with concurrent discards,
> +     * so it's special, as well as background snapshots.
> +     */
> +    return ram_block_discard_is_disabled() || migration_in_incoming_postcopy() ||
> +            migration_in_bg_snapshot();
>   }
>   
>   static void balloon_inflate_page(VirtIOBalloon *balloon,
> diff --git a/include/migration/misc.h b/include/migration/misc.h
> index bccc1b6b44..738675ef52 100644
> --- a/include/migration/misc.h
> +++ b/include/migration/misc.h
> @@ -70,6 +70,8 @@ bool migration_in_postcopy_after_devices(MigrationState *);
>   void migration_global_dump(Monitor *mon);
>   /* True if incomming migration entered POSTCOPY_INCOMING_DISCARD */
>   bool migration_in_incoming_postcopy(void);
> +/* True if background snapshot is active */
> +bool migration_in_bg_snapshot(void);
>   
>   /* migration/block-dirty-bitmap.c */
>   void dirty_bitmap_mig_init(void);
> diff --git a/migration/migration.c b/migration/migration.c
> index 496cf6e17b..656d6249a6 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -1976,6 +1976,14 @@ bool migration_in_incoming_postcopy(void)
>       return ps >= POSTCOPY_INCOMING_DISCARD && ps < POSTCOPY_INCOMING_END;
>   }
>   
> +bool migration_in_bg_snapshot(void)
> +{
> +    MigrationState *s = migrate_get_current();
> +
> +    return migrate_background_snapshot() &&
> +            migration_is_setup_or_active(s->state);
> +}
> +
>   bool migration_is_idle(void)
>   {
>       MigrationState *s = current_migration;
> 

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Thanks,

David / dhildenb
Re: [PATCH 2/3] migration: Inhibit virtio-balloon for the duration of background snapshot
Posted by Andrey Gruzdev 4 years, 10 months ago 
On 18.03.2021 21:16, David Hildenbrand wrote:
> On 18.03.21 18:46, Andrey Gruzdev wrote:
>> The same thing as for incoming postcopy - we cannot deal with concurrent
>> RAM discards when using background snapshot feature in outgoing 
>> migration.
>>
>> Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
>> ---
>>   hw/virtio/virtio-balloon.c | 8 ++++++--
>>   include/migration/misc.h   | 2 ++
>>   migration/migration.c      | 8 ++++++++
>>   3 files changed, 16 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
>> index e770955176..d120bf8f43 100644
>> --- a/hw/virtio/virtio-balloon.c
>> +++ b/hw/virtio/virtio-balloon.c
>> @@ -66,8 +66,12 @@ static bool 
>> virtio_balloon_pbp_matches(PartiallyBalloonedPage *pbp,
>>     static bool virtio_balloon_inhibited(void)
>>   {
>> -    /* Postcopy cannot deal with concurrent discards, so it's 
>> special. */
>> -    return ram_block_discard_is_disabled() || 
>> migration_in_incoming_postcopy();
>> +    /*
>> +     * Postcopy cannot deal with concurrent discards,
>> +     * so it's special, as well as background snapshots.
>> +     */
>> +    return ram_block_discard_is_disabled() || 
>> migration_in_incoming_postcopy() ||
>> +            migration_in_bg_snapshot();
>>   }
>>     static void balloon_inflate_page(VirtIOBalloon *balloon,
>> diff --git a/include/migration/misc.h b/include/migration/misc.h
>> index bccc1b6b44..738675ef52 100644
>> --- a/include/migration/misc.h
>> +++ b/include/migration/misc.h
>> @@ -70,6 +70,8 @@ bool 
>> migration_in_postcopy_after_devices(MigrationState *);
>>   void migration_global_dump(Monitor *mon);
>>   /* True if incomming migration entered POSTCOPY_INCOMING_DISCARD */
>>   bool migration_in_incoming_postcopy(void);
>> +/* True if background snapshot is active */
>> +bool migration_in_bg_snapshot(void);
>>     /* migration/block-dirty-bitmap.c */
>>   void dirty_bitmap_mig_init(void);
>> diff --git a/migration/migration.c b/migration/migration.c
>> index 496cf6e17b..656d6249a6 100644
>> --- a/migration/migration.c
>> +++ b/migration/migration.c
>> @@ -1976,6 +1976,14 @@ bool migration_in_incoming_postcopy(void)
>>       return ps >= POSTCOPY_INCOMING_DISCARD && ps < 
>> POSTCOPY_INCOMING_END;
>>   }
>>   +bool migration_in_bg_snapshot(void)
>> +{
>> +    MigrationState *s = migrate_get_current();
>> +
>> +    return migrate_background_snapshot() &&
>> +            migration_is_setup_or_active(s->state);
>> +}
>> +
>>   bool migration_is_idle(void)
>>   {
>>       MigrationState *s = current_migration;
>>
>
> Reviewed-by: David Hildenbrand <david@redhat.com>
>
Thanks!

-- 
Andrey Gruzdev, Principal Engineer
Virtuozzo GmbH  +7-903-247-6397
                 virtuzzo.com

Patchew 2.1-devel-b67e4c2

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