Re: [PATCH] cgroup/misc: Expose misc.current on cgroup v2 root

[Tejun Heo <tj@kernel.org>]

On Tue, Jun 13, 2023 at 06:59:29PM +0800, LeiZhou-97 wrote:
> Hello,
> 
> This patch is to expose misc.current on cgroup v2 root for tracking
> how much of the resource has been consumed in total on the system.
> 
> Most of the cloud infrastucture use cgroup to fetch the host
> information for scheduling purpose.
> 
> Currently, the misc controller can be used by Intel TDX HKIDs and
> AMD SEV ASIDs, which are both used for creating encrypted VMs.
> Intel TDX and AMD SEV are mostly be used by the cloud providers
> for providing confidential VMs.
> 
> In actual use of a server, these confidential VMs may be launched
> in different ways. For the cloud solution, there are kubvirt and
> coco (tracked by kubepods.slice); on host, they can be booted
> directly through qemu by end user (tracked by user.slice), etc.
> 
> In this complex environment, when wanting to know how many resource
> is used in total it has to iterate through all existing slices to
> get the value of each misc.current and add them up to calculate
> the total number of consumed keys.
> 
> So exposing misc.current to root cgroup tends to give much easier
> when calculates how much resource has been used in total, which
> helps to schedule and count resources for the cloud infrastucture.
> 
> Signed-off-by: LeiZhou-97 <lei.zhou@intel.com>

Applied to cgroup/for-6.5.

Thanks.

-- 
tejun