[PATCH 2/4] qemu: Add qemu parallel migration parameters

[Jiri Denemark]

On Fri, Jan 20, 2023 at 16:47:41 +0800, Jiang Jiacheng wrote:
> Add qemu migration parameters to support setting multifd
> migration compression method and level.
> 
> Signed-off-by: Jiang Jiacheng <jiangjiacheng at huawei.com>
> ---
>  src/qemu/qemu_migration.h        |  2 ++
>  src/qemu/qemu_migration_params.c | 24 +++++++++++++++++++++++-
>  src/qemu/qemu_migration_params.h |  3 +++
>  3 files changed, 28 insertions(+), 1 deletion(-)
> 
...
> diff --git a/src/qemu/qemu_migration_params.c b/src/qemu/qemu_migration_params.c
> index bd09dcfb23..380fc7dccd 100644
> --- a/src/qemu/qemu_migration_params.c
> +++ b/src/qemu/qemu_migration_params.c
...
> @@ -662,7 +682,9 @@ qemuMigrationParamsFromFlags(virTypedParameterPtr params,
>          return NULL;
>      }
>  
> -    if (migParams->params[QEMU_MIGRATION_PARAM_MULTIFD_CHANNELS].set &&
> +    if ((migParams->params[QEMU_MIGRATION_PARAM_MULTIFD_CHANNELS].set ||
> +         migParams->params[QEMU_MIGRATION_PARAM_MULTIFD_ZLIB_LEVEL].set ||
> +         migParams->params[QEMU_MIGRATION_PARAM_MULTIFD_ZSTD_LEVEL].set) &&
>          !(flags & VIR_MIGRATE_PARALLEL)) {
>          virReportError(VIR_ERR_INVALID_ARG, "%s",
>                         _("Turn parallel migration on to tune it"));

This check doesn't really make sense here. The new parameters tune
multifd compression (if enabled) rather than multifd migration itself.

> diff --git a/src/qemu/qemu_migration_params.h b/src/qemu/qemu_migration_params.h
> index e7c65f6a21..5857673227 100644
> --- a/src/qemu/qemu_migration_params.h
> +++ b/src/qemu/qemu_migration_params.h
> @@ -59,6 +59,9 @@ typedef enum {
>      QEMU_MIGRATION_PARAM_XBZRLE_CACHE_SIZE,
>      QEMU_MIGRATION_PARAM_MAX_POSTCOPY_BANDWIDTH,
>      QEMU_MIGRATION_PARAM_MULTIFD_CHANNELS,
> +    QEMU_MIGRATION_PARAM_MULTIFD_COMPRESSION,
> +    QEMU_MIGRATION_PARAM_MULTIFD_ZLIB_LEVEL,
> +    QEMU_MIGRATION_PARAM_MULTIFD_ZSTD_LEVEL,
>  
>      QEMU_MIGRATION_PARAM_LAST
>  } qemuMigrationParam;

And this patch should actually be squashed into the next one.

Jirka