Hi, On 6/29/22 21:48, Srinivas Pandruvada wrote: > On a multiple package system using Sub-NUMA clustering, there is an issue > in mapping Linux CPU number to PUNIT PCI device when manufacturer decided > to reuse the PCI bus number across packages. Bus number can be reused as > long as they are in different domain or segment. In this case some CPU > will fail to find a PCI device to issue SST requests. > > When bus numbers are reused across CPU packages, we are using proximity > information by matching CPU numa node id to PUNIT PCI device numa node > id. But on a package there can be only one PUNIT PCI device, but multiple > numa nodes (one for each sub cluster). So, the numa node ID of the PUNIT > PCI device can only match with one numa node id of CPUs in a sub cluster > in the package. > > Since there can be only one PUNIT PCI device per package, if we match > with numa node id of any sub cluster in that package, we can use that > mapping for any CPU in that package. So, store the match information > in a per package data structure and return the information when there > is no match. > > While here, use defines for max bus number instead of hardcoding. > > Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx> Thank you for your patch, I've applied this patch to my review-hans branch: https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans Note it will show up in my review-hans branch once I've pushed my local branch there, which might take a while. Once I've run some tests on this branch the patches there will be added to the platform-drivers-x86/for-next branch and eventually will be included in the pdx86 pull-request to Linus for the next merge-window. Regards, Hans > --- > v2 > - Use #define for max bus number and use > > .../intel/speed_select_if/isst_if_common.c | 39 +++++++++++++++---- > 1 file changed, 32 insertions(+), 7 deletions(-) > > diff --git a/drivers/platform/x86/intel/speed_select_if/isst_if_common.c b/drivers/platform/x86/intel/speed_select_if/isst_if_common.c > index e8424e70d81d..fd102678c75f 100644 > --- a/drivers/platform/x86/intel/speed_select_if/isst_if_common.c > +++ b/drivers/platform/x86/intel/speed_select_if/isst_if_common.c > @@ -277,29 +277,38 @@ static int isst_if_get_platform_info(void __user *argp) > return 0; > } > > +#define ISST_MAX_BUS_NUMBER 2 > > struct isst_if_cpu_info { > /* For BUS 0 and BUS 1 only, which we need for PUNIT interface */ > - int bus_info[2]; > - struct pci_dev *pci_dev[2]; > + int bus_info[ISST_MAX_BUS_NUMBER]; > + struct pci_dev *pci_dev[ISST_MAX_BUS_NUMBER]; > int punit_cpu_id; > int numa_node; > }; > > +struct isst_if_pkg_info { > + struct pci_dev *pci_dev[ISST_MAX_BUS_NUMBER]; > +}; > + > 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) > { > struct pci_dev *matched_pci_dev = NULL; > struct pci_dev *pci_dev = NULL; > - int no_matches = 0; > + int no_matches = 0, pkg_id; > int i, bus_number; > > - if (bus_no < 0 || bus_no > 1 || cpu < 0 || cpu >= nr_cpu_ids || > - cpu >= num_possible_cpus()) > + if (bus_no < 0 || bus_no >= ISST_MAX_BUS_NUMBER || cpu < 0 || > + cpu >= nr_cpu_ids || cpu >= num_possible_cpus()) > return NULL; > > + pkg_id = topology_physical_package_id(cpu); > + > bus_number = isst_cpu_info[cpu].bus_info[bus_no]; > if (bus_number < 0) > return NULL; > @@ -324,6 +333,8 @@ 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; > + > pci_dev = _pci_dev; > break; > } > @@ -342,6 +353,10 @@ 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; > > + /* Return pci_dev pointer for any matched CPU in the package */ > + if (!pci_dev) > + pci_dev = isst_pkg_info[pkg_id].pci_dev[bus_no]; > + > return pci_dev; > } > > @@ -361,8 +376,8 @@ struct pci_dev *isst_if_get_pci_dev(int cpu, int bus_no, int dev, int fn) > { > struct pci_dev *pci_dev; > > - if (bus_no < 0 || bus_no > 1 || cpu < 0 || cpu >= nr_cpu_ids || > - cpu >= num_possible_cpus()) > + if (bus_no < 0 || bus_no >= ISST_MAX_BUS_NUMBER || cpu < 0 || > + cpu >= nr_cpu_ids || cpu >= num_possible_cpus()) > return NULL; > > pci_dev = isst_cpu_info[cpu].pci_dev[bus_no]; > @@ -417,10 +432,19 @@ 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 +457,7 @@ 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); > }; >
