linux/mm/mm_init.c
<<
>>
Prefs
   1/*
   2 * mm_init.c - Memory initialisation verification and debugging
   3 *
   4 * Copyright 2008 IBM Corporation, 2008
   5 * Author Mel Gorman <mel@csn.ul.ie>
   6 *
   7 */
   8#include <linux/kernel.h>
   9#include <linux/init.h>
  10#include <linux/kobject.h>
  11#include <linux/export.h>
  12#include <linux/memory.h>
  13#include <linux/notifier.h>
  14#include <linux/sched.h>
  15#include "internal.h"
  16
  17#ifdef CONFIG_DEBUG_MEMORY_INIT
  18int __meminitdata mminit_loglevel;
  19
  20#ifndef SECTIONS_SHIFT
  21#define SECTIONS_SHIFT  0
  22#endif
  23
  24/* The zonelists are simply reported, validation is manual. */
  25void __init mminit_verify_zonelist(void)
  26{
  27        int nid;
  28
  29        if (mminit_loglevel < MMINIT_VERIFY)
  30                return;
  31
  32        for_each_online_node(nid) {
  33                pg_data_t *pgdat = NODE_DATA(nid);
  34                struct zone *zone;
  35                struct zoneref *z;
  36                struct zonelist *zonelist;
  37                int i, listid, zoneid;
  38
  39                BUG_ON(MAX_ZONELISTS > 2);
  40                for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
  41
  42                        /* Identify the zone and nodelist */
  43                        zoneid = i % MAX_NR_ZONES;
  44                        listid = i / MAX_NR_ZONES;
  45                        zonelist = &pgdat->node_zonelists[listid];
  46                        zone = &pgdat->node_zones[zoneid];
  47                        if (!populated_zone(zone))
  48                                continue;
  49
  50                        /* Print information about the zonelist */
  51                        printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
  52                                listid > 0 ? "thisnode" : "general", nid,
  53                                zone->name);
  54
  55                        /* Iterate the zonelist */
  56                        for_each_zone_zonelist(zone, z, zonelist, zoneid)
  57                                pr_cont("%d:%s ", zone_to_nid(zone), zone->name);
  58                        pr_cont("\n");
  59                }
  60        }
  61}
  62
  63void __init mminit_verify_pageflags_layout(void)
  64{
  65        int shift, width;
  66        unsigned long or_mask, add_mask;
  67
  68        shift = 8 * sizeof(unsigned long);
  69        width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH - LAST_CPUPID_SHIFT;
  70        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
  71                "Section %d Node %d Zone %d Lastcpupid %d Flags %d\n",
  72                SECTIONS_WIDTH,
  73                NODES_WIDTH,
  74                ZONES_WIDTH,
  75                LAST_CPUPID_WIDTH,
  76                NR_PAGEFLAGS);
  77        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
  78                "Section %d Node %d Zone %d Lastcpupid %d\n",
  79                SECTIONS_SHIFT,
  80                NODES_SHIFT,
  81                ZONES_SHIFT,
  82                LAST_CPUPID_SHIFT);
  83        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
  84                "Section %lu Node %lu Zone %lu Lastcpupid %lu\n",
  85                (unsigned long)SECTIONS_PGSHIFT,
  86                (unsigned long)NODES_PGSHIFT,
  87                (unsigned long)ZONES_PGSHIFT,
  88                (unsigned long)LAST_CPUPID_PGSHIFT);
  89        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
  90                "Node/Zone ID: %lu -> %lu\n",
  91                (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
  92                (unsigned long)ZONEID_PGOFF);
  93        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
  94                "location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
  95                shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
  96#ifdef NODE_NOT_IN_PAGE_FLAGS
  97        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
  98                "Node not in page flags");
  99#endif
 100#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
 101        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
 102                "Last cpupid not in page flags");
 103#endif
 104
 105        if (SECTIONS_WIDTH) {
 106                shift -= SECTIONS_WIDTH;
 107                BUG_ON(shift != SECTIONS_PGSHIFT);
 108        }
 109        if (NODES_WIDTH) {
 110                shift -= NODES_WIDTH;
 111                BUG_ON(shift != NODES_PGSHIFT);
 112        }
 113        if (ZONES_WIDTH) {
 114                shift -= ZONES_WIDTH;
 115                BUG_ON(shift != ZONES_PGSHIFT);
 116        }
 117
 118        /* Check for bitmask overlaps */
 119        or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
 120                        (NODES_MASK << NODES_PGSHIFT) |
 121                        (SECTIONS_MASK << SECTIONS_PGSHIFT);
 122        add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
 123                        (NODES_MASK << NODES_PGSHIFT) +
 124                        (SECTIONS_MASK << SECTIONS_PGSHIFT);
 125        BUG_ON(or_mask != add_mask);
 126}
 127
 128static __init int set_mminit_loglevel(char *str)
 129{
 130        get_option(&str, &mminit_loglevel);
 131        return 0;
 132}
 133early_param("mminit_loglevel", set_mminit_loglevel);
 134#endif /* CONFIG_DEBUG_MEMORY_INIT */
 135
 136struct kobject *mm_kobj;
 137EXPORT_SYMBOL_GPL(mm_kobj);
 138
 139#ifdef CONFIG_SMP
 140s32 vm_committed_as_batch = 32;
 141
 142static void __meminit mm_compute_batch(void)
 143{
 144        u64 memsized_batch;
 145        s32 nr = num_present_cpus();
 146        s32 batch = max_t(s32, nr*2, 32);
 147
 148        /* batch size set to 0.4% of (total memory/#cpus), or max int32 */
 149        memsized_batch = min_t(u64, (totalram_pages/nr)/256, 0x7fffffff);
 150
 151        vm_committed_as_batch = max_t(s32, memsized_batch, batch);
 152}
 153
 154static int __meminit mm_compute_batch_notifier(struct notifier_block *self,
 155                                        unsigned long action, void *arg)
 156{
 157        switch (action) {
 158        case MEM_ONLINE:
 159        case MEM_OFFLINE:
 160                mm_compute_batch();
 161        default:
 162                break;
 163        }
 164        return NOTIFY_OK;
 165}
 166
 167static struct notifier_block compute_batch_nb __meminitdata = {
 168        .notifier_call = mm_compute_batch_notifier,
 169        .priority = IPC_CALLBACK_PRI, /* use lowest priority */
 170};
 171
 172static int __init mm_compute_batch_init(void)
 173{
 174        mm_compute_batch();
 175        register_hotmemory_notifier(&compute_batch_nb);
 176
 177        return 0;
 178}
 179
 180__initcall(mm_compute_batch_init);
 181
 182#endif
 183
 184static int __init mm_sysfs_init(void)
 185{
 186        mm_kobj = kobject_create_and_add("mm", kernel_kobj);
 187        if (!mm_kobj)
 188                return -ENOMEM;
 189
 190        return 0;
 191}
 192postcore_initcall(mm_sysfs_init);
 193