LXR linux/mm/mm

   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/module.h>
  12#include "internal.h"
  13
  14#ifdef CONFIG_DEBUG_MEMORY_INIT
  15int mminit_loglevel;
  16
  17#ifndef SECTIONS_SHIFT
  18#define SECTIONS_SHIFT  0
  19#endif
  20
  21/* The zonelists are simply reported, validation is manual. */
  22void mminit_verify_zonelist(void)
  23{
  24        int nid;
  25
  26        if (mminit_loglevel < MMINIT_VERIFY)
  27                return;
  28
  29        for_each_online_node(nid) {
  30                pg_data_t *pgdat = NODE_DATA(nid);
  31                struct zone *zone;
  32                struct zoneref *z;
  33                struct zonelist *zonelist;
  34                int i, listid, zoneid;
  35
  36                BUG_ON(MAX_ZONELISTS > 2);
  37                for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
  38
  39                        /* Identify the zone and nodelist */
  40                        zoneid = i % MAX_NR_ZONES;
  41                        listid = i / MAX_NR_ZONES;
  42                        zonelist = &pgdat->node_zonelists[listid];
  43                        zone = &pgdat->node_zones[zoneid];
  44                        if (!populated_zone(zone))
  45                                continue;
  46
  47                        /* Print information about the zonelist */
  48                        printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
  49                                listid > 0 ? "thisnode" : "general", nid,
  50                                zone->name);
  51
  52                        /* Iterate the zonelist */
  53                        for_each_zone_zonelist(zone, z, zonelist, zoneid) {
  54#ifdef CONFIG_NUMA
  55                                printk(KERN_CONT "%d:%s ",
  56                                        zone->node, zone->name);
  57#else
  58                                printk(KERN_CONT "0:%s ", zone->name);
  59#endif /* CONFIG_NUMA */
  60                        }
  61                        printk(KERN_CONT "\n");
  62                }
  63        }
  64}
  65
  66void __init mminit_verify_pageflags_layout(void)
  67{
  68        int shift, width;
  69        unsigned long or_mask, add_mask;
  70
  71        shift = 8 * sizeof(unsigned long);
  72        width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH;
  73        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
  74                "Section %d Node %d Zone %d Flags %d\n",
  75                SECTIONS_WIDTH,
  76                NODES_WIDTH,
  77                ZONES_WIDTH,
  78                NR_PAGEFLAGS);
  79        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
  80                "Section %d Node %d Zone %d\n",
  81                SECTIONS_SHIFT,
  82                NODES_SHIFT,
  83                ZONES_SHIFT);
  84        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_offsets",
  85                "Section %lu Node %lu Zone %lu\n",
  86                (unsigned long)SECTIONS_PGSHIFT,
  87                (unsigned long)NODES_PGSHIFT,
  88                (unsigned long)ZONES_PGSHIFT);
  89        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_zoneid",
  90                "Zone ID: %lu -> %lu\n",
  91                (unsigned long)ZONEID_PGOFF,
  92                (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT));
  93        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
  94                "location: %d -> %d unused %d -> %d flags %d -> %d\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
 101        if (SECTIONS_WIDTH) {
 102                shift -= SECTIONS_WIDTH;
 103                BUG_ON(shift != SECTIONS_PGSHIFT);
 104        }
 105        if (NODES_WIDTH) {
 106                shift -= NODES_WIDTH;
 107                BUG_ON(shift != NODES_PGSHIFT);
 108        }
 109        if (ZONES_WIDTH) {
 110                shift -= ZONES_WIDTH;
 111                BUG_ON(shift != ZONES_PGSHIFT);
 112        }
 113
 114        /* Check for bitmask overlaps */
 115        or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
 116                        (NODES_MASK << NODES_PGSHIFT) |
 117                        (SECTIONS_MASK << SECTIONS_PGSHIFT);
 118        add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
 119                        (NODES_MASK << NODES_PGSHIFT) +
 120                        (SECTIONS_MASK << SECTIONS_PGSHIFT);
 121        BUG_ON(or_mask != add_mask);
 122}
 123
 124void __meminit mminit_verify_page_links(struct page *page, enum zone_type zone,
 125                        unsigned long nid, unsigned long pfn)
 126{
 127        BUG_ON(page_to_nid(page) != nid);
 128        BUG_ON(page_zonenum(page) != zone);
 129        BUG_ON(page_to_pfn(page) != pfn);
 130}
 131
 132static __init int set_mminit_loglevel(char *str)
 133{
 134        get_option(&str, &mminit_loglevel);
 135        return 0;
 136}
 137early_param("mminit_loglevel", set_mminit_loglevel);
 138#endif /* CONFIG_DEBUG_MEMORY_INIT */
 139
 140struct kobject *mm_kobj;
 141EXPORT_SYMBOL_GPL(mm_kobj);
 142
 143static int __init mm_sysfs_init(void)
 144{
 145        mm_kobj = kobject_create_and_add("mm", kernel_kobj);
 146        if (!mm_kobj)
 147                return -ENOMEM;
 148
 149        return 0;
 150}
 151
 152__initcall(mm_sysfs_init);
 153