[libvirt] [PATCH V2] cpuset: Add cpuset cgroup support.

[Gui Jianfeng]

On 2011-7-2 9:42, Gui Jianfeng wrote:
> Currently, libvirt makes use of sched_setaffinity() to set Guest's cpu
> affinity. But, sometimes, for instance, when QEmu uses vhost-net, the
> kernel part of vhost will create a kernel thread for some purpose. In this
> case, such kernel thread won't inherit QEmu's cpu affinity.
> 
> This patch enables cpuset cgroup in libvirt and setting cpu affinity by
> configuring cpuset cgroup.

Ping?

Gui

> 
> Signed-off-by: Gui Jianfeng <guijianfeng at cn.fujitsu.com>
> ---
>  src/libvirt_private.syms |    1 +
>  src/qemu/qemu_cgroup.c   |   18 ++++++++++++++++++
>  src/qemu/qemu_conf.c     |    3 ++-
>  src/util/cgroup.c        |   18 ++++++++++++++++++
>  src/util/cgroup.h        |    2 ++
>  5 files changed, 41 insertions(+), 1 deletions(-)
> 
> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
> index 626ac6c..e7aebc7 100644
> --- a/src/libvirt_private.syms
> +++ b/src/libvirt_private.syms
> @@ -83,6 +83,7 @@ virCgroupMounted;
>  virCgroupPathOfController;
>  virCgroupRemove;
>  virCgroupSetBlkioWeight;
> +virCgroupCpusetSetcpus;
>  virCgroupSetCpuShares;
>  virCgroupSetFreezerState;
>  virCgroupSetMemory;
> diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c
> index 1298924..413bee4 100644
> --- a/src/qemu/qemu_cgroup.c
> +++ b/src/qemu/qemu_cgroup.c
> @@ -296,6 +296,24 @@ int qemuSetupCgroup(struct qemud_driver *driver,
>          }
>      }
> 
> +    if (vm->def->cpumask != NULL &&
> +        qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPUSET)) {
> +            char *cpumask = NULL;
> +            if ((cpumask =
> +                 virDomainCpuSetFormat(vm->def->cpumask, vm->def->cpumasklen)) == NULL)
> +                goto cleanup;
> +
> +            rc = virCgroupCpusetSetcpus(cgroup, cpumask);
> +            if(rc != 0) {
> +                virReportSystemError(-rc,
> +                                     _("Unable to set cpus for domain %s"),
> +                                     vm->def->name);
> +                VIR_FREE(cpumask);
> +                goto cleanup;
> +            }
> +            VIR_FREE(cpumask);
> +    }
> +
>      if (vm->def->blkio.weight != 0) {
>          if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_BLKIO)) {
>              rc = virCgroupSetBlkioWeight(cgroup, vm->def->blkio.weight);
> diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
> index 3d8aba4..8b478c4 100644
> --- a/src/qemu/qemu_conf.c
> +++ b/src/qemu/qemu_conf.c
> @@ -307,7 +307,8 @@ int qemudLoadDriverConfig(struct qemud_driver *driver,
>              (1 << VIR_CGROUP_CONTROLLER_CPU) |
>              (1 << VIR_CGROUP_CONTROLLER_DEVICES) |
>              (1 << VIR_CGROUP_CONTROLLER_MEMORY) |
> -            (1 << VIR_CGROUP_CONTROLLER_BLKIO);
> +            (1 << VIR_CGROUP_CONTROLLER_BLKIO) |
> +            (1 << VIR_CGROUP_CONTROLLER_CPUSET);
>      }
>      for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
>          if (driver->cgroupControllers & (1 << i)) {
> diff --git a/src/util/cgroup.c b/src/util/cgroup.c
> index 2e5ef46..89b2ad4 100644
> --- a/src/util/cgroup.c
> +++ b/src/util/cgroup.c
> @@ -472,6 +472,24 @@ static int virCgroupCpuSetInherit(virCgroupPtr parent, virCgroupPtr group)
>      return rc;
>  }
> 
> +int virCgroupCpusetSetcpus(virCgroupPtr group, char *cpustring)
> +{
> +    int rc = 0;
> +    const char *key = "cpuset.cpus";
> +
> +    VIR_DEBUG("Cpuset: set %s for %s/%s", cpustring, group->path, key);
> +
> +    rc = virCgroupSetValueStr(group,
> +                              VIR_CGROUP_CONTROLLER_CPUSET,
> +                              key,
> +                              cpustring);
> +
> +    if (rc != 0)
> +        VIR_ERROR("Failed to set %s for %s/%s", cpustring, group->path, key);
> +
> +    return rc;
> +}
> +
>  static int virCgroupSetMemoryUseHierarchy(virCgroupPtr group)
>  {
>      int rc = 0;
> diff --git a/src/util/cgroup.h b/src/util/cgroup.h
> index 8ae756d..ca6a68a 100644
> --- a/src/util/cgroup.h
> +++ b/src/util/cgroup.h
> @@ -30,6 +30,8 @@ enum {
> 
>  VIR_ENUM_DECL(virCgroupController);
> 
> +int virCgroupCpusetSetcpus(virCgroupPtr group, char *cpustring);
> +
>  int virCgroupForDriver(const char *name,
>                         virCgroupPtr *group,
>                         int privileged,