arch/s390/numa/numa.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * NUMA support for s390
   4  *
   5  * Implement NUMA core code.
   6  *
   7  * Copyright IBM Corp. 2015
   8  */
   9
  10 #define KMSG_COMPONENT "numa"
  11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  12
  13 #include <linux/kernel.h>
  14 #include <linux/mmzone.h>
  15 #include <linux/cpumask.h>
  16 #include <linux/bootmem.h>
  17 #include <linux/memblock.h>
  18 #include <linux/slab.h>
  19 #include <linux/node.h>
  20
  21 #include <asm/numa.h>
  22 #include "numa_mode.h"
  23
  24 pg_data_t *node_data[MAX_NUMNODES];
  25 EXPORT_SYMBOL(node_data);
  26
  27 cpumask_t node_to_cpumask_map[MAX_NUMNODES];
  28 EXPORT_SYMBOL(node_to_cpumask_map);
  29
  30 static void plain_setup(void)
  31 {
  32         node_set(0, node_possible_map);
  33 }
  34
  35 const struct numa_mode numa_mode_plain = {
  36         .name = "plain",
  37         .setup = plain_setup,
  38 };
  39
  40 static const struct numa_mode *mode = &numa_mode_plain;
  41
  42 int numa_pfn_to_nid(unsigned long pfn)
  43 {
  44         return mode->__pfn_to_nid ? mode->__pfn_to_nid(pfn) : 0;
  45 }
  46
  47 void numa_update_cpu_topology(void)
  48 {
  49         if (mode->update_cpu_topology)
  50                 mode->update_cpu_topology();
  51 }
  52
  53 int __node_distance(int a, int b)
  54 {
  55         return mode->distance ? mode->distance(a, b) : 0;
  56 }
  57 EXPORT_SYMBOL(__node_distance);
  58
  59 int numa_debug_enabled;
  60
  61 /*
  62  * alloc_node_data() - Allocate node data
  63  */
  64 static __init pg_data_t *alloc_node_data(void)
  65 {
  66         pg_data_t *res;
  67
  68         res = (pg_data_t *) memblock_alloc(sizeof(pg_data_t), 8);
  69         memset(res, 0, sizeof(pg_data_t));
  70         return res;
  71 }
  72
  73 /*
  74  * numa_setup_memory() - Assign bootmem to nodes
  75  *
  76  * The memory is first added to memblock without any respect to nodes.
  77  * This is fixed before remaining memblock memory is handed over to the
  78  * buddy allocator.
  79  * An important side effect is that large bootmem allocations might easily
  80  * cross node boundaries, which can be needed for large allocations with
  81  * smaller memory stripes in each node (i.e. when using NUMA emulation).
  82  *
  83  * Memory defines nodes:
  84  * Therefore this routine also sets the nodes online with memory.
  85  */
  86 static void __init numa_setup_memory(void)
  87 {
  88         unsigned long cur_base, align, end_of_dram;
  89         int nid = 0;
  90
  91         end_of_dram = memblock_end_of_DRAM();
  92         align = mode->align ? mode->align() : ULONG_MAX;
  93
  94         /*
  95          * Step through all available memory and assign it to the nodes
  96          * indicated by the mode implementation.
  97          * All nodes which are seen here will be set online.
  98          */
  99         cur_base = 0;
 100         do {
 101                 nid = numa_pfn_to_nid(PFN_DOWN(cur_base));
 102                 node_set_online(nid);
 103                 memblock_set_node(cur_base, align, &memblock.memory, nid);
 104                 cur_base += align;
 105         } while (cur_base < end_of_dram);
 106
 107         /* Allocate and fill out node_data */
 108         for (nid = 0; nid < MAX_NUMNODES; nid++)
 109                 NODE_DATA(nid) = alloc_node_data();
 110
 111         for_each_online_node(nid) {
 112                 unsigned long start_pfn, end_pfn;
 113                 unsigned long t_start, t_end;
 114                 int i;
 115
 116                 start_pfn = ULONG_MAX;
 117                 end_pfn = 0;
 118                 for_each_mem_pfn_range(i, nid, &t_start, &t_end, NULL) {
 119                         if (t_start < start_pfn)
 120                                 start_pfn = t_start;
 121                         if (t_end > end_pfn)
 122                                 end_pfn = t_end;
 123                 }
 124                 NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
 125                 NODE_DATA(nid)->node_id = nid;
 126         }
 127 }
 128
 129 /*
 130  * numa_setup() - Earliest initialization
 131  *
 132  * Assign the mode and call the mode's setup routine.
 133  */
 134 void __init numa_setup(void)
 135 {
 136         pr_info("NUMA mode: %s\n", mode->name);
 137         nodes_clear(node_possible_map);
 138         /* Initially attach all possible CPUs to node 0. */
 139         cpumask_copy(&node_to_cpumask_map[0], cpu_possible_mask);
 140         if (mode->setup)
 141                 mode->setup();
 142         numa_setup_memory();
 143         memblock_dump_all();
 144 }
 145
 146 /*
 147  * numa_init_late() - Initialization initcall
 148  *
 149  * Register NUMA nodes.
 150  */
 151 static int __init numa_init_late(void)
 152 {
 153         int nid;
 154
 155         for_each_online_node(nid)
 156                 register_one_node(nid);
 157         return 0;
 158 }
 159 arch_initcall(numa_init_late);
 160
 161 static int __init parse_debug(char *parm)
 162 {
 163         numa_debug_enabled = 1;
 164         return 0;
 165 }
 166 early_param("numa_debug", parse_debug);
 167
 168 static int __init parse_numa(char *parm)
 169 {
 170         if (strcmp(parm, numa_mode_plain.name) == 0)
 171                 mode = &numa_mode_plain;
 172 #ifdef CONFIG_NUMA_EMU
 173         if (strcmp(parm, numa_mode_emu.name) == 0)
 174                 mode = &numa_mode_emu;
 175 #endif
 176         return 0;
 177 }
 178 early_param("numa", parse_numa);