Re: [PATCH V5 03/25] cpr: QMP interfaces for reboot

[Steven Sistare <steven.sistare@oracle.com>]

Will do for all.  Good idea on schema introspection. - steve

On 7/8/2021 9:27 AM, Marc-André Lureau wrote:
> Hi
> 
> On Wed, Jul 7, 2021 at 9:28 PM Steve Sistare <steven.sistare@oracle.com <mailto:steven.sistare@oracle.com>> wrote:
> 
>     cprsave calls cprsave().  Syntax:
>       { 'enum': 'CprMode', 'data': [ 'reboot' ] }
>       { 'command': 'cprsave', 'data': { 'file': 'str', 'mode': 'CprMode' } }
> 
>     cprload calls cprload().  Syntax:
>       { 'command': 'cprload', 'data': { 'file': 'str' } }
> 
>     cprinfo returns a list of supported modes.  Syntax:
>       { 'struct': 'CprInfo', 'data': { 'modes': [ 'CprMode' ] } }
>       { 'command': 'cprinfo', 'returns': 'CprInfo' }
> 
> 
> It may not be necessary, we may instead rely on query-qmp-schema introspection.
> 
> 
>     Signed-off-by: Mark Kanda <mark.kanda@oracle.com <mailto:mark.kanda@oracle.com>>
>     Signed-off-by: Steve Sistare <steven.sistare@oracle.com <mailto:steven.sistare@oracle.com>>
>     ---
>      MAINTAINERS           |  1 +
>      monitor/qmp-cmds.c    | 31 +++++++++++++++++++++
>      qapi/cpr.json         | 74 +++++++++++++++++++++++++++++++++++++++++++++++++++
>      qapi/meson.build      |  1 +
>      qapi/qapi-schema.json |  1 +
>      5 files changed, 108 insertions(+)
>      create mode 100644 qapi/cpr.json
> 
>     diff --git a/MAINTAINERS b/MAINTAINERS
>     index c3573aa..c48dd37 100644
>     --- a/MAINTAINERS
>     +++ b/MAINTAINERS
>     @@ -2864,6 +2864,7 @@ M: Mark Kanda <mark.kanda@oracle.com <mailto:mark.kanda@oracle.com>>
>      S: Maintained
>      F: include/migration/cpr.h
>      F: migration/cpr.c
>     +F: qapi/cpr.json
> 
>      Record/replay
>      M: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru <mailto:pavel.dovgaluk@ispras.ru>>
>     diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
>     index f7d64a6..1128604 100644
>     --- a/monitor/qmp-cmds.c
>     +++ b/monitor/qmp-cmds.c
>     @@ -37,9 +37,11 @@
>      #include "qapi/qapi-commands-machine.h"
>      #include "qapi/qapi-commands-misc.h"
>      #include "qapi/qapi-commands-ui.h"
>     +#include "qapi/qapi-commands-cpr.h"
>      #include "qapi/qmp/qerror.h"
>      #include "hw/mem/memory-device.h"
>      #include "hw/acpi/acpi_dev_interface.h"
>     +#include "migration/cpr.h"
> 
>      NameInfo *qmp_query_name(Error **errp)
>      {
>     @@ -153,6 +155,35 @@ void qmp_cont(Error **errp)
>          }
>      }
> 
>     +CprInfo *qmp_cprinfo(Error **errp)
>     +{
>     +    CprInfo *cprinfo;
>     +    CprModeList *mode, *mode_list = NULL;
>     +    CprMode i;
>     +
>     +    cprinfo = g_malloc0(sizeof(*cprinfo));
>     +
>     +    for (i = 0; i < CPR_MODE__MAX; i++) {
>     +        mode = g_malloc0(sizeof(*mode));
>     +        mode->value = i;
>     +        mode->next = mode_list;
>     +        mode_list = mode;
>     +    }
>     +
>     +    cprinfo->modes = mode_list;
>     +    return cprinfo;
>     +}
>     +
>     +void qmp_cprsave(const char *file, CprMode mode, Error **errp)
>     +{
>     +    cprsave(file, mode, errp);
>     +}
>     +
>     +void qmp_cprload(const char *file, Error **errp)
>     +{
>     +    cprload(file, errp);
>     +}
>     +
>      void qmp_system_wakeup(Error **errp)
>      {
>          if (!qemu_wakeup_suspend_enabled()) {
>     diff --git a/qapi/cpr.json b/qapi/cpr.json
>     new file mode 100644
>     index 0000000..b6fdc89
>     --- /dev/null
>     +++ b/qapi/cpr.json
>     @@ -0,0 +1,74 @@
>     +# -*- Mode: Python -*-
>     +#
>     +# Copyright (c) 2021 Oracle and/or its affiliates.
>     +#
>     +# This work is licensed under the terms of the GNU GPL, version 2.
>     +# See the COPYING file in the top-level directory.
>     +
>     +##
>     +# = CPR
> 
> 
> Please spell it out in the doc at least (it's not obvious, I had to search for the meaning in list archives ;).
> 
>     +##
>     +
>     +{ 'include': 'common.json' }
>     +
>     +##
>     +# @CprMode:
>     +#
>     +# @reboot: checkpoint can be cprload'ed after a host kexec reboot.
>     +#
>     +# Since: 6.1
>     +##
>     +{ 'enum': 'CprMode',
>     +  'data': [ 'reboot' ] }
>     +
>     +
>     +##
>     +# @CprInfo:
>     +#
>     +# @modes: @CprMode list
>     +#
>     +# Since: 6.1
>     +##
>     +{ 'struct': 'CprInfo',
>     +  'data': { 'modes': [ 'CprMode' ] } }
>     +
>     +##
>     +# @cprinfo:
>     +#
>     +# Returns the modes supported by @cprsave.
>     +#
>     +# Returns: @CprInfo
>     +#
>     +# Since: 6.1
>     +#
>     +##
>     +{ 'command': 'cprinfo',
>     +  'returns': 'CprInfo' }
>     +
>     +##
>     +# @cprsave:
>     +#
>     +# Create a checkpoint of the virtual machine device state in @file.
>     +# Guest RAM and guest block device blocks are not saved.
>     +#
> 
> 
> It would be worth highlighting the differences with snapshot-save/load.
> 
> I guess it would make sense to consider this as an extension/variant to those commands.
>  
> 
>     +# @file: name of checkpoint file
>     +# @mode: @CprMode mode
>     +#
>     +# Since: 6.1
>     +##
>     +{ 'command': 'cprsave',
>     +  'data': { 'file': 'str',
>     +            'mode': 'CprMode' } }
>     +
>     +##
>     +# @cprload:
>     +#
>     +# Start virtual machine from checkpoint file that was created earlier using
>     +# the cprsave command.
>     +#
>     +# @file: name of checkpoint file
>     +#
>     +# Since: 6.1
>     +##
>     +{ 'command': 'cprload',
>     +  'data': { 'file': 'str' } }
>     diff --git a/qapi/meson.build b/qapi/meson.build
>     index 376f4ce..7e7c48a 100644
>     --- a/qapi/meson.build
>     +++ b/qapi/meson.build
>     @@ -26,6 +26,7 @@ qapi_all_modules = [
>        'common',
>        'compat',
>        'control',
>     +  'cpr',
>        'crypto',
>        'dump',
>        'error',
>     diff --git a/qapi/qapi-schema.json b/qapi/qapi-schema.json
>     index 4912b97..001d790 100644
>     --- a/qapi/qapi-schema.json
>     +++ b/qapi/qapi-schema.json
>     @@ -77,6 +77,7 @@
>      { 'include': 'ui.json' }
>      { 'include': 'authz.json' }
>      { 'include': 'migration.json' }
>     +{ 'include': 'cpr.json' }
>      { 'include': 'transaction.json' }
>      { 'include': 'trace.json' }
>      { 'include': 'compat.json' }
>     -- 
>     1.8.3.1
> 
> 
> 
> 
> -- 
> Marc-André Lureau