[patch V4 35/41] x86/mm/numa: Use core domain size on AMD

Thomas Gleixner
2023-08-14T08:56:41Z

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 <mikelley@microsoft.com>

---
arch/x86/mm/amdtopology.c | 35 ++++++++++++++++-------------------
1 file changed, 16 insertions(+), 19 deletions(-)

--- 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;
+ 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);
}
-
- 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);
-
return 0;
}