Re: [Xen-devel] [PATCH v9 12/25] x86: refactor psr: L3 CAT: set value: implement cos id picking flow.

[Yi Sun <yi.y.sun@xxxxxxxxxxxxxxx>]

On 17-03-30 05:55:52, Jan Beulich wrote:
> >>> On 30.03.17 at 03:37, <yi.y.sun@xxxxxxxxxxxxxxx> wrote:
> > On 17-03-29 03:57:52, Jan Beulich wrote:
> >> >>> On 29.03.17 at 03:36, <yi.y.sun@xxxxxxxxxxxxxxx> wrote:
> >> > On 17-03-29 09:20:21, Yi Sun wrote:
> >> >> On 17-03-28 06:20:48, Jan Beulich wrote:
> >> >> > >>> On 28.03.17 at 13:59, <yi.y.sun@xxxxxxxxxxxxxxx> wrote:
> >> >> > > I think we at least need a 'get_val()' hook.
> >> >> > 
> >> >> > Of course.
> >> >> > 
> >> >> > > I try to implement CAT/CDP hook.
> >> >> > > Please help to check if this is what you thought.
> >> >> > 
> >> >> > One remark below, but other than that - yes.
> >> >> > 
> >> >> > > static void cat_get_val(const struct feat_node *feat, unsigned int 
> >> >> > > cos,
> >> >> > >                         enum cbm_type type, int flag, uint32_t *val)
> >> >> > > {
> >> >> > >     *val = feat->cos_reg_val[cos];
> >> >> > > }
> >> >> > > 
> >> >> > > static void l3_cdp_get_val(const struct feat_node *feat, unsigned 
> >> >> > > int 
> > cos,
> >> >> > >                            enum cbm_type type, int flag, uint32_t 
> >> >> > > *val)
> >> >> > > {
> >> >> > >     if ( type == PSR_CBM_TYPE_L3_DATA || flag == 0 )
> >> >> > >         *val = get_cdp_data(feat, cos);
> >> >> > >     if ( type == PSR_CBM_TYPE_L3_CODE || flag == 1 )
> >> >> > >         *val = get_cdp_code(feat, cos);
> >> >> > > }
> >> >> > 
> >> >> > Why the redundancy between type and flag?
> >> >> > 
> >> >> For psr_get_val, upper layer input the cbm_type to get either DATA or 
> >> >> CODE
> >> >> value. For other cases, we use flag as cos_num index to get either DATA 
> >> >> or
> >> >> CODE.
> >> >> 
> >> > Let me explain more to avoid confusion. For other cases, we use cos_num 
> >> > as
> >> > index to get values from a feature. In these cases, we do not know the
> >> > cbm_type of the feature. So, I use the cos_num as flag to make 'get_val'
> >> > know which value should be returned.
> >> 
> >> I'm pretty sure this redundancy can be avoided.
> >> 
> > Then, I think I have to reuse the 'type'. As only CDP needs type to decide
> > which value to be returned so far, I think I can implement codes like below
> > to make CDP can handle all scenarios.
> > 
> > static void l3_cdp_get_val(const struct feat_node *feat, unsigned int cos,
> >                            enum cbm_type type, uint32_t *val)
> > {
> >     if ( type == PSR_CBM_TYPE_L3_DATA || flag == 0xF000 )
> >         *val = get_cdp_data(feat, cos);
> >     if ( type == PSR_CBM_TYPE_L3_CODE || flag == 0xF001 )
> >         *val = get_cdp_code(feat, cos);
> > }
> > 
> > static bool fits_cos_max(...)
> > {
> > ......
> >     for (i = 0; i < feat->props->cos_num; i++)
> >     {
> >         feat->props->get_val(feat, cos, i + 0xF000, &default_val);
> >         if ( val[i] == default_val )
> >             ......
> >     }
> > ......
> > }
> > 
> > Is that good for you?
> 
> Urgh - no, not really: This is hackery. Do you have a tree
> somewhere so I could look at the file after at least the CDP
> patches have all been applied, to see whether I have a
> better idea? Alternatively, could you attach psr.c the way
> you have it right now with the entire series applied?
> 
I think you can check v9 codes here:
https://github.com/yisun-git/xen/tree/l2_cat_v9

Thanks,
Sun Yi

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel