numa.c (1858B)
1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * 4 * ia64 kernel NUMA specific stuff 5 * 6 * Copyright (C) 2002 Erich Focht <efocht@ess.nec.de> 7 * Copyright (C) 2004 Silicon Graphics, Inc. 8 * Jesse Barnes <jbarnes@sgi.com> 9 */ 10#include <linux/topology.h> 11#include <linux/module.h> 12#include <asm/processor.h> 13#include <asm/smp.h> 14 15u16 cpu_to_node_map[NR_CPUS] __cacheline_aligned; 16EXPORT_SYMBOL(cpu_to_node_map); 17 18cpumask_t node_to_cpu_mask[MAX_NUMNODES] __cacheline_aligned; 19EXPORT_SYMBOL(node_to_cpu_mask); 20 21void map_cpu_to_node(int cpu, int nid) 22{ 23 int oldnid; 24 if (nid < 0) { /* just initialize by zero */ 25 cpu_to_node_map[cpu] = 0; 26 return; 27 } 28 /* sanity check first */ 29 oldnid = cpu_to_node_map[cpu]; 30 if (cpumask_test_cpu(cpu, &node_to_cpu_mask[oldnid])) { 31 return; /* nothing to do */ 32 } 33 /* we don't have cpu-driven node hot add yet... 34 In usual case, node is created from SRAT at boot time. */ 35 if (!node_online(nid)) 36 nid = first_online_node; 37 cpu_to_node_map[cpu] = nid; 38 cpumask_set_cpu(cpu, &node_to_cpu_mask[nid]); 39 return; 40} 41 42void unmap_cpu_from_node(int cpu, int nid) 43{ 44 WARN_ON(!cpumask_test_cpu(cpu, &node_to_cpu_mask[nid])); 45 WARN_ON(cpu_to_node_map[cpu] != nid); 46 cpu_to_node_map[cpu] = 0; 47 cpumask_clear_cpu(cpu, &node_to_cpu_mask[nid]); 48} 49 50 51/** 52 * build_cpu_to_node_map - setup cpu to node and node to cpumask arrays 53 * 54 * Build cpu to node mapping and initialize the per node cpu masks using 55 * info from the node_cpuid array handed to us by ACPI. 56 */ 57void __init build_cpu_to_node_map(void) 58{ 59 int cpu, i, node; 60 61 for(node=0; node < MAX_NUMNODES; node++) 62 cpumask_clear(&node_to_cpu_mask[node]); 63 64 for_each_possible_early_cpu(cpu) { 65 node = NUMA_NO_NODE; 66 for (i = 0; i < NR_CPUS; ++i) 67 if (cpu_physical_id(cpu) == node_cpuid[i].phys_id) { 68 node = node_cpuid[i].nid; 69 break; 70 } 71 map_cpu_to_node(cpu, node); 72 } 73}