Re: [PATCH v5 02/18] cgroup/misc: Add SGX EPC resource type and export APIs for SGX driver

Tejun Heo
2023-09-25T18:50:22Z

On Fri, Sep 22, 2023 at 08:06:41PM -0700, Haitao Huang wrote:
> From: Kristen Carlson Accardi <kristen@linux.intel.com>
>
> Add SGX EPC memory, MISC_CG_RES_SGX_EPC, to be a valid resource type
> for the misc controller.
>
> Add per resource type private data so that SGX can store additional per
> cgroup data in misc_cg->misc_cg_res[MISC_CG_RES_SGX_EPC].
>
> Export misc_cg_root() so the SGX driver can initialize and add those
> additional structures to the root misc cgroup as part of initialization
> for EPC cgroup support. This bootstraps the same additional
> initialization for non-root cgroups in the 'alloc()' callback added in the
> previous patch.
>
> The SGX driver, as the EPC memory provider, will have a background
> worker to reclaim EPC pages to make room for new allocations in the same
> cgroup when its usage counter reaches near the limit controlled by the
> cgroup and its ancestors. Therefore it needs to do a walk from the
> current cgroup up to the root. To enable this walk, move parent_misc()
> into misc_cgroup.h and make inline to make this function available to
> SGX, rename it to misc_cg_parent(), and update kernel/cgroup/misc.c to
> use the new name.
>
> Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
> Signed-off-by: Haitao Huang <haitao.huang@linux.intel.com>

Acked-by: Tejun Heo <tj@kernel.org>

Thanks.

--
tejun