Re: [PATCH 5/6] vmdk: Flush only once in vmdk_L2update()

[Eric Blake]

On 4/30/20 8:30 AM, Kevin Wolf wrote:
> If we have a backup L2 table, we currently flush once after writing to
> the active L2 table and again after writing to the backup table. A
> single flush is enough and makes things a little less slow.
>
> Signed-off-by: Kevin Wolf <address@hidden>
> ---
>   block/vmdk.c | 7 +++++--
>   1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/block/vmdk.c b/block/vmdk.c
> index dcd30f1419..d3eb9a5cdc 100644
> --- a/block/vmdk.c
> +++ b/block/vmdk.c
> @@ -1435,7 +1435,7 @@ static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData 
> *m_data,
>       offset = cpu_to_le32(offset);
>       /* update L2 table */
>       BLKDBG_EVENT(extent->file, BLKDBG_L2_UPDATE);
> -    if (bdrv_pwrite_sync(extent->file,
> +    if (bdrv_pwrite(extent->file,
>                   ((int64_t)m_data->l2_offset * 512)
>                       + (m_data->l2_index * sizeof(offset)),
>                   &offset, sizeof(offset)) < 0) {

Worth reindenting ther est of the function call?

> @@ -1444,13 +1444,16 @@ static int vmdk_L2update(VmdkExtent *extent, 
> VmdkMetaData *m_data,
>       /* update backup L2 table */
>       if (extent->l1_backup_table_offset != 0) {
>           m_data->l2_offset = extent->l1_backup_table[m_data->l1_index];
> -        if (bdrv_pwrite_sync(extent->file,
> +        if (bdrv_pwrite(extent->file,
>                       ((int64_t)m_data->l2_offset * 512)
>                           + (m_data->l2_index * sizeof(offset)),
>                       &offset, sizeof(offset)) < 0) {
>               return VMDK_ERROR;
>           }
>       }
> +    if (bdrv_flush(extent->file->bs) < 0) {
> +        return VMDK_ERROR;
> +    }

But indentation doesn't affect correctness.

Reviewed-by: Eric Blake <address@hidden>

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org