Re: [PATCH v16 08/16] x86/sgx: Encapsulate uses of the global LRU

["Jarkko Sakkinen" <jarkko@kernel.org>]

On Wed Aug 21, 2024 at 4:53 AM EEST, Haitao Huang wrote:
> To support the per-cgroup reclamation, each cgroup will have its own
> "per-cgroup LRU" and EPC pages will be in its owner cgroup's LRU instead
> of the global LRU. Abstract the code that is directly working with the
> global LRU into functions reusable with per-cgroup LRUs.
>
> Currently the basic reclamation procedure, sgx_reclaim_pages() directly
> reclaims pages from the global LRU. Change it to take in an LRU.
>
> Note the global EPC reclamation will still be needed when the total EPC
> usage reaches the system capacity while usages of some cgroups are below
> their respective limits. Create a separate wrapper for the global
> reclamation, sgx_reclaim_pages_global(), passing in the global LRU to
> the new sgx_reclaim_pages() now. Later it will be revised to reclaim
> from multiple LRUs from all EPC cgroups instead of a single global LRU.
>
> Wrap the existing emptiness check of the global LRU with a helper so
> that it can be changed later to work with multiple LRUs when per-cgroup
> LRU comes to play.
>
> Also the per-cgroup EPC reclaim and global EPC reclaim will have
> different check on whether they should be done.  Rename the existing
> sgx_should_reclaim() to sgx_should_reclaim_global() to separate the two
> cases.
>
> Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> Co-developed-by: Kristen Carlson Accardi <kristen@linux.intel.com>
> Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
> Signed-off-by: Haitao Huang <haitao.huang@linux.intel.com>

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko