x86/mm/numa: Use core domain size on AMD

cpuinfo::topo::x86_coreid_bits is about to be phased out. Use the core
domain size from the topology information.

Add a comment why the early MPTABLE parsing is required and decrapify the
loop which sets the APIC ID to node map.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.270320718@linutronix.de

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index 9bca92bdaa058a8681d3ca249e0bc6918e1ee96b..be27ef77d45e934e9609ac7477f26009d9710436 100644 (file)
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -121,6 +121,11 @@ struct x86_topology_system {
 
 extern struct x86_topology_system x86_topo_system;
 
+static inline unsigned int topology_get_domain_size(enum x86_topology_domains dom)
+{
+       return x86_topo_system.dom_size[dom];
+}
+
 extern const struct cpumask *cpu_coregroup_mask(int cpu);
 extern const struct cpumask *cpu_clustergroup_mask(int cpu);
 

diff --git a/arch/x86/mm/amdtopology.c b/arch/x86/mm/amdtopology.c
index b3ca7d23e4b01c7ae719e954408c234d21d89cdf..5681b997b35748041edf9159f1f706ca15374266 100644 (file)
--- a/arch/x86/mm/amdtopology.c
+++ b/arch/x86/mm/amdtopology.c
@@ -54,13 +54,11 @@ static __init int find_northbridge(void)
 
 int __init amd_numa_init(void)
 {
-       u64 start = PFN_PHYS(0);
+       unsigned int numnodes, cores, apicid;
+       u64 prevbase, start = PFN_PHYS(0);
        u64 end = PFN_PHYS(max_pfn);
-       unsigned numnodes;
-       u64 prevbase;
-       int i, j, nb;
        u32 nodeid, reg;
-       unsigned int bits, cores, apicid_base;
+       int i, j, nb;
 
        if (!early_pci_allowed())
                return -EINVAL;
@@ -158,26 +156,25 @@ int __init amd_numa_init(void)
                return -ENOENT;
 
        /*
-        * We seem to have valid NUMA configuration.  Map apicids to nodes
-        * using the coreid bits from early_identify_cpu.
+        * We seem to have valid NUMA configuration. Map apicids to nodes
+        * using the size of the core domain in the APIC space.
         */
-       bits = boot_cpu_data.x86_coreid_bits;
-       cores = 1 << bits;
-       apicid_base = 0;
+       cores = topology_get_domain_size(TOPO_CORE_DOMAIN);
 
        /*
-        * get boot-time SMP configuration:
+        * Scan MPTABLE to map the local APIC and ensure that the boot CPU
+        * APIC ID is valid. This is required because on pre ACPI/SRAT
+        * systems IO-APICs are mapped before the boot CPU.
         */
        early_get_smp_config();
 
-       if (boot_cpu_physical_apicid > 0) {
-               pr_info("BSP APIC ID: %02x\n", boot_cpu_physical_apicid);
-               apicid_base = boot_cpu_physical_apicid;
-       }
-
-       for_each_node_mask(i, numa_nodes_parsed)
-               for (j = apicid_base; j < cores + apicid_base; j++)
-                       set_apicid_to_node((i << bits) + j, i);
+       apicid = boot_cpu_physical_apicid;
+       if (apicid > 0)
+               pr_info("BSP APIC ID: %02x\n", apicid);
 
+       for_each_node_mask(i, numa_nodes_parsed) {
+               for (j = 0; j < cores; j++, apicid++)
+                       set_apicid_to_node(apicid, i);
+       }
        return 0;
 }