Re: [PATCH] platform/x86: ISST: PUNIT device mapping with Sub-NUMA clustering

[srinivas pandruvada <srinivas.pandruvada@linux.intel.com>]

Hi Hans,

Thanks for the review.

On Wed, 2022-06-29 at 12:00 +0200, Hans de Goede wrote:
> Hi,
> 
> On 6/27/22 23:50, Srinivas Pandruvada wrote:
> > 
[...]

> >  
> > +struct isst_if_pkg_info {
> > +       struct pci_dev *pci_dev[2];
> 
> This and (continued below) ...
> 
Didn't understand the comment.

> > +};
> > +
> >  static struct isst_if_cpu_info *isst_cpu_info;
> > +static struct isst_if_pkg_info *isst_pkg_info;
> > +
> >  #define ISST_MAX_PCI_DOMAINS   8
> >  
> >  static struct pci_dev *_isst_if_get_pci_dev(int cpu, int bus_no,
> > int dev, int fn)
> >  {
> > +       int pkg_id = topology_physical_package_id(cpu);
> >         struct pci_dev *matched_pci_dev = NULL;
> >         struct pci_dev *pci_dev = NULL;
> >         int no_matches = 0;
> > @@ -324,6 +331,8 @@ static struct pci_dev *_isst_if_get_pci_dev(int
> > cpu, int bus_no, int dev, int fn
> >                 }
> >  
> >                 if (node == isst_cpu_info[cpu].numa_node) {
> > +                       isst_pkg_info[pkg_id].pci_dev[bus_no] =
> > _pci_dev;
> > +
> 
> This and ...
> 
Please explain the comment.

> >                         pci_dev = _pci_dev;
> >                         break;
> >                 }
> > @@ -342,6 +351,9 @@ static struct pci_dev *_isst_if_get_pci_dev(int
> > cpu, int bus_no, int dev, int fn
> >         if (!pci_dev && no_matches == 1)
> >                 pci_dev = matched_pci_dev;
> >  
> > +       if (!pci_dev)
> > +               pci_dev = isst_pkg_info[pkg_id].pci_dev[bus_no];
> > +
> 
> This assumes that bus_no is never > 1, is this assumption enforced
> somewhere?
> 
Yes. That is checked at the beginning of function
   if (bus_no < 0 || bus_no > 1 || cpu < 0 || cpu >= nr_cpu_ids ||
            cpu >= num_possible_cpus())
	 return NULL;


> Also maybe make the 2 in:
> 
> > +struct isst_if_pkg_info {
> > +       struct pci_dev *pci_dev[2];
> 
> a #define ?
I will.

Thanks,
Srinivas

> 
> Regards,
> 
> Hans
> 
> 
> >         return pci_dev;
> >  }
> >  
> > @@ -417,10 +429,19 @@ static int isst_if_cpu_info_init(void)
> >         if (!isst_cpu_info)
> >                 return -ENOMEM;
> >  
> > +       isst_pkg_info = kcalloc(topology_max_packages(),
> > +                               sizeof(*isst_pkg_info),
> > +                               GFP_KERNEL);
> > +       if (!isst_pkg_info) {
> > +               kfree(isst_cpu_info);
> > +               return -ENOMEM;
> > +       }
> > +
> >         ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
> >                                 "platform/x86/isst-if:online",
> >                                 isst_if_cpu_online, NULL);
> >         if (ret < 0) {
> > +               kfree(isst_pkg_info);
> >                 kfree(isst_cpu_info);
> >                 return ret;
> >         }
> > @@ -433,6 +454,7 @@ static int isst_if_cpu_info_init(void)
> >  static void isst_if_cpu_info_exit(void)
> >  {
> >         cpuhp_remove_state(isst_if_online_id);
> > +       kfree(isst_pkg_info);
> >         kfree(isst_cpu_info);
> >  };
> >  
>