[libvirt] [PATCH 6/8] Implement schedular tunables API using cgroups

[Daniel Veillard]

On Wed, Jul 22, 2009 at 04:23:45PM +0100, Daniel P. Berrange wrote:
> * src/qemu_driver.c:  Add driver methods qemuGetSchedulerType,
>   qemuGetSchedulerParameters, qemuSetSchedulerParameters
> * src/lxc_driver.c: Fix to use unsigned long long consistently
>   for schedular parameters
> * src/cgroup.h, src/cgroup.c: Fix cpu_shares to take unsigned
>   long long
> * src/util.c, src/util.h, src/libvirt_private.syms: Add a
>   virStrToDouble helper
> * src/virsh.c: Fix handling of --set arg to schedinfo command
>   to honour the designated data type of each schedular tunable
>   as declared by the driver
> 
> Signed-off-by: Daniel P. Berrange <berrange at redhat.com>
> ---
>  src/cgroup.c             |   10 +-
>  src/cgroup.h             |    4 +-
>  src/libvirt_private.syms |    1 +
>  src/lxc_driver.c         |    9 ++-
>  src/qemu_driver.c        |  151 +++++++++++++++++++++++++++++-
>  src/util.c               |   20 ++++
>  src/util.h               |    3 +
[...]
> @@ -1355,9 +1355,14 @@ static int lxcSetSchedulerParameters(virDomainPtr domain,
>  
>      for (i = 0; i < nparams; i++) {
>          virSchedParameterPtr param = &params[i];
> +        if (param->type != VIR_DOMAIN_SCHED_FIELD_ULLONG) {
> +            lxcError(NULL, domain, VIR_ERR_INVALID_ARG,
> +                     _("invalid type for cpu_shares tunable, expected a 'ullong'"));
> +            goto cleanup;
> +        }

  Humpf, we are actually breaking the API in some ways there, what is
  the argument ? Consistency with qemu scheduling parameters ?

>          if (STREQ(param->field, "cpu_shares")) {
[...]
> +        if (STREQ(param->field, "cpu_shares")) {
> +            int rc;
> +            if (param->type != VIR_DOMAIN_SCHED_FIELD_ULLONG) {

  Apparently, but is that worth it ?

[...]
> --- a/src/virsh.c
> +++ b/src/virsh.c
> @@ -1181,111 +1181,118 @@ static const vshCmdOptDef opts_schedinfo[] = {
>  };
>  
>  static int
> -cmdSchedinfo(vshControl *ctl, const vshCmd *cmd)
> +cmdSchedInfoUpdate(vshControl *ctl, const vshCmd *cmd,
> +                   virSchedParameterPtr param)
>  {
[...]
> +    /* Legacy 'weight' parameter */
> +    if (STREQ(param->field, "weight") &&
> +        param->type == VIR_DOMAIN_SCHED_FIELD_UINT &&
> +        vshCommandOptBool(cmd, "weight")) {
> +        int val;
> +        val = vshCommandOptInt(cmd, "weight", &found);
> +        if (!found) {
>              vshError(ctl, FALSE, "%s", _("Invalid value of weight"));
> -            goto cleanup;
> +            return -1;
>          } else {
> -            nr_inputparams++;
> +            param->value.ui = val;
>          }
> +        return 1;

  This API is and remains a pain, looking at the ESX driver there is
  just yet another completely different set ...


  ACK, though the lxc breakage is a bit nasty IMHO

Daniel

-- 
Daniel Veillard      | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
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