Re: [Xen-devel] [PATCH v8 16/24] x86: refactor psr: implement set value callback functions for CDP.

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

On 17-02-26 17:43:55, Wei Liu wrote:
> On Wed, Feb 15, 2017 at 04:49:31PM +0800, Yi Sun wrote:
> > This patch implements L3 CDP set value related callback functions.
> > 
> > With this patch, 'psr-cat-cbm-set' command can work for L3 CDP.
> > 
> > Signed-off-by: Yi Sun <yi.y.sun@xxxxxxxxxxxxxxx>
> > ---
> > v8:
> >     - modify 'l3_cdp_write_msr' to 'void'.
> > ---
> >  xen/arch/x86/psr.c | 118 
> > +++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 118 insertions(+)
> > 
> > diff --git a/xen/arch/x86/psr.c b/xen/arch/x86/psr.c
> > index 72ed923..0a0bab9 100644
> > --- a/xen/arch/x86/psr.c
> > +++ b/xen/arch/x86/psr.c
> > @@ -560,10 +560,128 @@ static bool l3_cdp_get_val(const struct feat_node 
> > *feat, unsigned int cos,
> >      return true;
> >  }
> >  
> > +static unsigned int l3_cdp_get_cos_num(const struct feat_node *feat)
> > +{
> > +    return 2;
> 
> Please avoid using magic number, or document where 2 comes from.
> 
Will add comment to explain this.

> > +}
> > +
> > +static int l3_cdp_get_old_val(uint64_t val[],
> 
> Hmm... so val is indeed an array. I think we need to pass the length as
> well.
> 
I explained it in previous match to address your comment. The array length
is checked in caller function. Is that acceptable to you?

> > +                              const struct feat_node *feat,
> > +                              unsigned int old_cos)
> > +{
> > +    if ( old_cos > feat->info.l3_cdp_info.cos_max )
> > +        /* Use default value. */
> > +        old_cos = 0;
> > +
> > +    /* Data */
> > +    val[0] = get_cdp_data(feat, old_cos);
> > +    /* Code */
> > +    val[1] = get_cdp_code(feat, old_cos);
> > +
> > +    return 0;
> > +}
> > +
> > +static int l3_cdp_set_new_val(uint64_t val[],
> > +                              const struct feat_node *feat,
> > +                              enum cbm_type type,
> > +                              uint64_t m)
> > +{
> > +    if ( !psr_check_cbm(feat->info.l3_cdp_info.cbm_len, m) )
> > +        return -EINVAL;
> > +
> > +    if ( type == PSR_CBM_TYPE_L3_DATA )
> > +        val[0] = m;
> > +    else
> > +        val[1] = m;
> > +
> > +    return 0;
> > +}
> > +
> > +static int l3_cdp_compare_val(const uint64_t val[],
> > +                              const struct feat_node *feat,
> > +                              unsigned int cos, bool *found)
> > +{
> > +    uint64_t l3_def_cbm;
> > +
> > +    l3_def_cbm = (1ull << feat->info.l3_cdp_info.cbm_len) - 1;
> 
> This is getting repetitive. Please consider providing a macro to
> calculate this value.
> 
Ok, thanks!

> Wei.

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