Re: [PATCH v4 15/18] x86/sgx: Prepare for multiple LRUs

[Haitao Huang]

On Wed, 13 Sep 2023 10:42:52 -0500, Jarkko Sakkinen <jarkko@xxxxxxxxxx>  
wrote:

> On Wed Sep 13, 2023 at 7:06 AM EEST, Haitao Huang wrote:
> > Add sgx_can_reclaim() wrapper and encapsulate direct references to the
> > global LRU list in the reclaimer functions so that they can be called  
> > with
> > an LRU list per EPC cgroup.
> >
> > Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> > Signed-off-by: Kristen Carlson Accardi <kristen@xxxxxxxxxxxxxxx>
> > Signed-off-by: Haitao Huang <haitao.huang@xxxxxxxxxxxxxxx>
> > Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
> > ---
> > V4:
> > - Re-organized this patch to include all changes related to
> > encapsulation of the global LRU
> > - Moved this patch to precede the EPC cgroup patch
> > ---
> >  arch/x86/kernel/cpu/sgx/main.c | 41 +++++++++++++++++++++++-----------
> >  1 file changed, 28 insertions(+), 13 deletions(-)
> >
> > diff --git a/arch/x86/kernel/cpu/sgx/main.c  
> > b/arch/x86/kernel/cpu/sgx/main.c
> > index ce316bd5e5bb..3d396fe5ec09 100644
> > --- a/arch/x86/kernel/cpu/sgx/main.c
> > +++ b/arch/x86/kernel/cpu/sgx/main.c
> > @@ -34,6 +34,16 @@ static DEFINE_XARRAY(sgx_epc_address_space);
> >   */
> >  static struct sgx_epc_lru_lists sgx_global_lru;
> >
> > +static inline struct sgx_epc_lru_lists *sgx_lru_lists(struct  
> > sgx_epc_page *epc_page)
> > +{
> > +	return &sgx_global_lru;
> > +}
>
> I'd simply export sgx_global_lru.
The purpose of this patch to to hide sgx_global_lru so later we can have  
LRU per cgroup.
I'll update the commit message to make it clear this is not just for   
sgx_can_reclaim

> > +static inline bool sgx_can_reclaim(void)
> > +{
> > +	return !list_empty(&sgx_global_lru.reclaimable);
> > +}
>
>
> Accessors for the object should be named so that this fact is reflected,
> e.g. sgx_global_lru_can_reclaim() in this case.
>
> I would just open code this to the call sites though.
ditto

Thanks
Haitao