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