[libvirt] [PATCH v5 6/7] Implement qemuSetupGlobalCpuCgroup

[Maxim Nestratov]

18.01.2016 13:08, Alexander Burluka пишет:
> This functions setups per-domain cpu bandwidth parameters
>
> Signed-off-by: Alexander Burluka <aburluka at virtuozzo.com>
> ---
>   src/qemu/qemu_cgroup.c  | 54 +++++++++++++++++++++++++++++++++++++++++++++++++
>   src/qemu/qemu_cgroup.h  |  1 +
>   src/qemu/qemu_process.c |  4 ++++
>   3 files changed, 59 insertions(+)
>
> diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c
> index 452d71d..1638bfe 100644
> --- a/src/qemu/qemu_cgroup.c
> +++ b/src/qemu/qemu_cgroup.c
> @@ -1002,6 +1002,60 @@ qemuSetupCgroupCpusetCpus(virCgroupPtr cgroup,
>   }
>   
>   int
> +qemuSetupGlobalCpuCgroup(virDomainObjPtr vm)
> +{
> +    qemuDomainObjPrivatePtr priv = vm->privateData;
> +    unsigned long long period = vm->def->cputune.global_period;
> +    long long quota = vm->def->cputune.global_quota;
> +    char *mem_mask = NULL;
> +    virDomainNumatuneMemMode mem_mode;
> +
> +    if ((period || quota) &&
> +        !virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPU)) {
> +        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
> +                       _("cgroup cpu is required for scheduler tuning"));
> +        return -1;
> +    }
> +
> +    /*
> +     * If CPU cgroup controller is not initialized here, then we need
> +     * neither period nor quota settings.  And if CPUSET controller is
> +     * not initialized either, then there's nothing to do anyway.
> +     */
> +    if (!virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPU) &&
> +        !virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPUSET))
> +        return 0;
> +
> +    /* We are trying to setup cgroups for CPU pinning, which can also be done
> +     * with virProcessSetAffinity, thus the lack of cgroups is not fatal here.
> +     */
> +    if (priv->cgroup == NULL)
> +        return 0;
This check is unnecessary because virCgroupHasController already has it.

> +
> +    if (virDomainNumatuneGetMode(vm->def->numa, -1, &mem_mode) == 0 &&
> +        mem_mode == VIR_DOMAIN_NUMATUNE_MEM_STRICT &&
> +        virDomainNumatuneMaybeFormatNodeset(vm->def->numa,
> +                                            priv->autoNodeset,
> +                                            &mem_mask, -1) < 0)
> +        goto cleanup;
I'd like to see the reason in error message here similar to error path 
at the beginning of the function.

> +
> +    if (period || quota) {
> +        if (qemuSetupBandwidthCgroup(priv->cgroup, period, quota) < 0)
> +            goto cleanup;
> +    }
> +
> +    VIR_FREE(mem_mask);
> +
> +    return 0;
> +
> + cleanup:
> +    VIR_FREE(mem_mask);
> +
> +    return -1;
> +}
> +
> +
> +int
>   qemuSetupCgroupForVcpu(virDomainObjPtr vm)
>   {
>       virCgroupPtr cgroup_vcpu = NULL;
> diff --git a/src/qemu/qemu_cgroup.h b/src/qemu/qemu_cgroup.h
> index 17da920..75f9eb7 100644
> --- a/src/qemu/qemu_cgroup.h
> +++ b/src/qemu/qemu_cgroup.h
> @@ -54,6 +54,7 @@ int qemuSetupBandwidthCgroup(virCgroupPtr cgroup,
>                                long long quota);
>   int qemuSetupCgroupCpusetCpus(virCgroupPtr cgroup, virBitmapPtr cpumask);
>   int qemuSetupCgroupForVcpu(virDomainObjPtr vm);
> +int qemuSetupGlobalCpuCgroup(virDomainObjPtr vm);
>   int qemuSetupCgroupForIOThreads(virDomainObjPtr vm);
>   int qemuSetupCgroupForEmulator(virDomainObjPtr vm);
>   int qemuRemoveCgroup(virQEMUDriverPtr driver, virDomainObjPtr vm);
> diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
> index 05cbda2..96c7a6a 100644
> --- a/src/qemu/qemu_process.c
> +++ b/src/qemu/qemu_process.c
> @@ -4982,6 +4982,10 @@ qemuProcessLaunch(virConnectPtr conn,
>       if (qemuProcessDetectIOThreadPIDs(driver, vm, asyncJob) < 0)
>           goto cleanup;
>   
> +    VIR_DEBUG("Setting global CPU cgroup (if required)");
> +    if (qemuSetupGlobalCpuCgroup(vm) < 0)
> +        goto cleanup;
> +
>       VIR_DEBUG("Setting cgroup for each VCPU (if required)");
>       if (qemuSetupCgroupForVcpu(vm) < 0)
>           goto cleanup;