[libvirt] [PATCH 08/12] qemu: Add length for bps/iops throttling parameters to driver

[John Ferlan]

On 09/23/2016 08:56 AM, John Ferlan wrote:
> Add support for a duration/length for the bps/iops and friends.
> 
> Modify the API in order to add the "blkdeviotune." specific definitions
> for the iotune throttling duration/length options
> 
>     total_bytes_sec_max_length
>     write_bytes_sec_max_length
>     read_bytes_sec_max_length
>     total_iops_sec_max_length
>     write_iops_sec_max_length
>     read_iops_sec_max_length
> 
> Signed-off-by: John Ferlan <jferlan at redhat.com>
> ---
>  include/libvirt/libvirt-domain.h |  54 ++++++++++++++++++++
>  src/conf/domain_conf.h           |   6 +++
>  src/qemu/qemu_driver.c           | 106 ++++++++++++++++++++++++++++++++++++++-
>  src/qemu/qemu_monitor.c          |   7 ++-
>  src/qemu/qemu_monitor.h          |   3 +-
>  src/qemu/qemu_monitor_json.c     |  25 ++++++++-
>  src/qemu/qemu_monitor_json.h     |   3 +-
>  tests/qemumonitorjsontest.c      |  17 ++++++-
>  8 files changed, 211 insertions(+), 10 deletions(-)
> 

While working on the "next" iotune tunable to add I realized something...

[...]

>  
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index ee16cb5..3b04754 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -113,7 +113,8 @@ VIR_LOG_INIT("qemu.qemu_driver");
>  #define QEMU_NB_MEM_PARAM  3
>  
>  #define QEMU_NB_BLOCK_IO_TUNE_PARAM  6
> -#define QEMU_NB_BLOCK_IO_TUNE_PARAM_MAX  13
> +#define QEMU_NB_BLOCK_IO_TUNE_PARAM_LENGTH 12
> +#define QEMU_NB_BLOCK_IO_TUNE_PARAM_MAX  19

These need to be:

#define QEMU_NB_BLOCK_IO_TUNE_PARAM  6
#define QEMU_NB_BLOCK_IO_TUNE_PARAM_MAX  13
#define QEMU_NB_BLOCK_IO_TUNE_PARAM_MAX_LENGTH 19

Then [...]


> @@ -17667,6 +17759,9 @@ qemuDomainGetBlockIoTune(virDomainPtr dom,
>  
>          if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DRIVE_IOTUNE_MAX))
>              maxparams = QEMU_NB_BLOCK_IO_TUNE_PARAM;
> +
> +        if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DRIVE_IOTUNE_MAX_LENGTH))
> +            maxparams = QEMU_NB_BLOCK_IO_TUNE_PARAM_LENGTH;
>      }

This should be :

        if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DRIVE_IOTUNE_MAX))
            maxparams = QEMU_NB_BLOCK_IO_TUNE_PARAM;
        else if (!virQEMUCapsGet(priv->qemuCaps,
                                 QEMU_CAPS_DRIVE_IOTUNE_MAX_LENGTH))
            maxparams = QEMU_NB_BLOCK_IO_TUNE_PARAM_MAX;


The default is 19 (get everything)... If we don't have the IOTUNE_MAX
cap, then there's only 6 parameters to get. If we don't have the
IOTUNE_MAX_LENGTH cap, then there's only 13 parameters to get.


John