[v1] migration/vfio: Fix a few issues on API misuse or statistic reports

[PATCH 02/14] migration/qapi: Rename MigrationStats to MigrationRAMStats

Posted by Peter Xu via Devel 3 days ago

This stats is only about RAM, make it accurate.  This paves way for
statistics for all devices.

Thanks to Markus, who pointed out that docs/devel/qapi-code-gen.rst has a
section "Compatibility considerations" stated:

    Since type names are not visible in the Client JSON Protocol, types
    may be freely renamed.  Even certain refactorings are invisible, such
    as splitting members from one type into a common base type.

Hence this change is not ABI violation according to the document.

While at it, touch up the lines to make it read better, correct the
restriction on migration status being 'active' or 'completed': over time we
grew too many new status that will also report "ram" section.

Cc: Daniel P. Berrangé <berrange@redhat.com>
Cc: devel@lists.libvirt.org
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 docs/about/removed-features.rst |  2 +-
 qapi/migration.json             | 10 +++++-----
 migration/migration-stats.h     |  2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/docs/about/removed-features.rst b/docs/about/removed-features.rst
index 557a24679a..ccd49b5615 100644
--- a/docs/about/removed-features.rst
+++ b/docs/about/removed-features.rst
@@ -699,7 +699,7 @@ was superseded by ``sections``.
 ``query-migrate`` return value member ``skipped`` (removed in 9.1)
 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 
-Member ``skipped`` of the ``MigrationStats`` struct hasn't been used
+Member ``skipped`` of the ``MigrationRAMStats`` struct hasn't been used
 for more than 10 years. Removed with no replacement.
 
 ``migrate`` command option ``inc`` (removed in 9.1)
diff --git a/qapi/migration.json b/qapi/migration.json
index 7134d4ce47..e3ad3f0604 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -12,7 +12,7 @@
 { 'include': 'sockets.json' }
 
 ##
-# @MigrationStats:
+# @MigrationRAMStats:
 #
 # Detailed migration status.
 #
@@ -64,7 +64,7 @@
 #
 # Since: 0.14
 ##
-{ 'struct': 'MigrationStats',
+{ 'struct': 'MigrationRAMStats',
   'data': {'transferred': 'int', 'remaining': 'int', 'total': 'int' ,
            'duplicate': 'int',
            'normal': 'int',
@@ -209,8 +209,8 @@
 #     If this field is not returned, no migration process has been
 #     initiated
 #
-# @ram: `MigrationStats` containing detailed migration status, only
-#     returned if status is 'active' or 'completed'(since 1.2)
+# @ram: Detailed migration RAM statistics, only returned if migration
+#     is in progress or completed (since 1.2)
 #
 # @xbzrle-cache: `XBZRLECacheStats` containing detailed XBZRLE
 #     migration statistics, only returned if XBZRLE feature is on and
@@ -309,7 +309,7 @@
 # Since: 0.14
 ##
 { 'struct': 'MigrationInfo',
-  'data': {'*status': 'MigrationStatus', '*ram': 'MigrationStats',
+  'data': {'*status': 'MigrationStatus', '*ram': 'MigrationRAMStats',
            '*vfio': 'VfioStats',
            '*xbzrle-cache': 'XBZRLECacheStats',
            '*total-time': 'int',
diff --git a/migration/migration-stats.h b/migration/migration-stats.h
index c0f50144c9..1153520f7a 100644
--- a/migration/migration-stats.h
+++ b/migration/migration-stats.h
@@ -27,7 +27,7 @@
 
 /*
  * These are the ram migration statistic counters.  It is loosely
- * based on MigrationStats.
+ * based on MigrationRAMStats.
  */
 typedef struct {
     /*
-- 
2.53.0

Re: [PATCH 02/14] migration/qapi: Rename MigrationStats to MigrationRAMStats

Posted by Michal Prívozník 1 day, 5 hours ago

On 4/8/26 18:55, Peter Xu via Devel wrote:
> This stats is only about RAM, make it accurate.  This paves way for
> statistics for all devices.
> 
> Thanks to Markus, who pointed out that docs/devel/qapi-code-gen.rst has a
> section "Compatibility considerations" stated:
> 
>     Since type names are not visible in the Client JSON Protocol, types
>     may be freely renamed.  Even certain refactorings are invisible, such
>     as splitting members from one type into a common base type.
> 
> Hence this change is not ABI violation according to the document.
> 
> While at it, touch up the lines to make it read better, correct the
> restriction on migration status being 'active' or 'completed': over time we
> grew too many new status that will also report "ram" section.
> 
> Cc: Daniel P. Berrangé <berrange@redhat.com>
> Cc: devel@lists.libvirt.org
> Reviewed-by: Markus Armbruster <armbru@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  docs/about/removed-features.rst |  2 +-
>  qapi/migration.json             | 10 +++++-----
>  migration/migration-stats.h     |  2 +-
>  3 files changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/docs/about/removed-features.rst b/docs/about/removed-features.rst
> index 557a24679a..ccd49b5615 100644
> --- a/docs/about/removed-features.rst
> +++ b/docs/about/removed-features.rst
> @@ -699,7 +699,7 @@ was superseded by ``sections``.
>  ``query-migrate`` return value member ``skipped`` (removed in 9.1)
>  ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
>  
> -Member ``skipped`` of the ``MigrationStats`` struct hasn't been used
> +Member ``skipped`` of the ``MigrationRAMStats`` struct hasn't been used
>  for more than 10 years. Removed with no replacement.
>  
>  ``migrate`` command option ``inc`` (removed in 9.1)
> diff --git a/qapi/migration.json b/qapi/migration.json
> index 7134d4ce47..e3ad3f0604 100644
> --- a/qapi/migration.json
> +++ b/qapi/migration.json
> @@ -12,7 +12,7 @@
>  { 'include': 'sockets.json' }
>  
>  ##
> -# @MigrationStats:
> +# @MigrationRAMStats:
>  #
>  # Detailed migration status.
>  #
> @@ -64,7 +64,7 @@
>  #
>  # Since: 0.14
>  ##
> -{ 'struct': 'MigrationStats',
> +{ 'struct': 'MigrationRAMStats',
>    'data': {'transferred': 'int', 'remaining': 'int', 'total': 'int' ,
>             'duplicate': 'int',
>             'normal': 'int',

Libvirt does not store/care about struct names really (only temporarily
when 'flattening' output of query-qmp-schema to see if a command has
certain argument, for instance). So from libvirt's POV:

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

Michal

Re: [PATCH 02/14] migration/qapi: Rename MigrationStats to MigrationRAMStats

Posted by Juraj Marcin 2 days ago

On 2026-04-08 12:55, Peter Xu wrote:
> This stats is only about RAM, make it accurate.  This paves way for
> statistics for all devices.
> 
> Thanks to Markus, who pointed out that docs/devel/qapi-code-gen.rst has a
> section "Compatibility considerations" stated:
> 
>     Since type names are not visible in the Client JSON Protocol, types
>     may be freely renamed.  Even certain refactorings are invisible, such
>     as splitting members from one type into a common base type.
> 
> Hence this change is not ABI violation according to the document.
> 
> While at it, touch up the lines to make it read better, correct the
> restriction on migration status being 'active' or 'completed': over time we
> grew too many new status that will also report "ram" section.
> 
> Cc: Daniel P. Berrangé <berrange@redhat.com>
> Cc: devel@lists.libvirt.org
> Reviewed-by: Markus Armbruster <armbru@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  docs/about/removed-features.rst |  2 +-
>  qapi/migration.json             | 10 +++++-----
>  migration/migration-stats.h     |  2 +-
>  3 files changed, 7 insertions(+), 7 deletions(-)
> 

Reviewed-by: Juraj Marcin <jmarcin@redhat.com>