mm/mm_init.c

   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 "internal.h"
  11
  12 #ifdef CONFIG_DEBUG_MEMORY_INIT
  13 int __meminitdata mminit_loglevel;
  14
  15 /* The zonelists are simply reported, validation is manual. */
  16 void mminit_verify_zonelist(void)
  17 {
  18         int nid;
  19
  20         if (mminit_loglevel < MMINIT_VERIFY)
  21                 return;
  22
  23         for_each_online_node(nid) {
  24                 pg_data_t *pgdat = NODE_DATA(nid);
  25                 struct zone *zone;
  26                 struct zoneref *z;
  27                 struct zonelist *zonelist;
  28                 int i, listid, zoneid;
  29
  30                 BUG_ON(MAX_ZONELISTS > 2);
  31                 for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
  32
  33                         /* Identify the zone and nodelist */
  34                         zoneid = i % MAX_NR_ZONES;
  35                         listid = i / MAX_NR_ZONES;
  36                         zonelist = &pgdat->node_zonelists[listid];
  37                         zone = &pgdat->node_zones[zoneid];
  38                         if (!populated_zone(zone))
  39                                 continue;
  40
  41                         /* Print information about the zonelist */
  42                         printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
  43                                 listid > 0 ? "thisnode" : "general", nid,
  44                                 zone->name);
  45
  46                         /* Iterate the zonelist */
  47                         for_each_zone_zonelist(zone, z, zonelist, zoneid) {
  48 #ifdef CONFIG_NUMA
  49                                 printk(KERN_CONT "%d:%s ",
  50                                         zone->node, zone->name);
  51 #else
  52                                 printk(KERN_CONT "0:%s ", zone->name);
  53 #endif /* CONFIG_NUMA */
  54                         }
  55                         printk(KERN_CONT "\n");
  56                 }
  57         }
  58 }
  59
  60 void __init mminit_verify_pageflags_layout(void)
  61 {
  62         int shift, width;
  63         unsigned long or_mask, add_mask;
  64
  65         shift = 8 * sizeof(unsigned long);
  66         width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH;
  67         mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
  68                 "Section %d Node %d Zone %d Flags %d\n",
  69                 SECTIONS_WIDTH,
  70                 NODES_WIDTH,
  71                 ZONES_WIDTH,
  72                 NR_PAGEFLAGS);
  73         mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
  74                 "Section %d Node %d Zone %d\n",
  75 #ifdef SECTIONS_SHIFT
  76                 SECTIONS_SHIFT,
  77 #else
  78                 0,
  79 #endif
  80                 NODES_SHIFT,
  81                 ZONES_SHIFT);
  82         mminit_dprintk(MMINIT_TRACE, "pageflags_layout_offsets",
  83                 "Section %lu Node %lu Zone %lu\n",
  84                 (unsigned long)SECTIONS_PGSHIFT,
  85                 (unsigned long)NODES_PGSHIFT,
  86                 (unsigned long)ZONES_PGSHIFT);
  87         mminit_dprintk(MMINIT_TRACE, "pageflags_layout_zoneid",
  88                 "Zone ID: %lu -> %lu\n",
  89                 (unsigned long)ZONEID_PGOFF,
  90                 (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT));
  91         mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
  92                 "location: %d -> %d unused %d -> %d flags %d -> %d\n",
  93                 shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
  94 #ifdef NODE_NOT_IN_PAGE_FLAGS
  95         mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
  96                 "Node not in page flags");
  97 #endif
  98
  99         if (SECTIONS_WIDTH) {
 100                 shift -= SECTIONS_WIDTH;
 101                 BUG_ON(shift != SECTIONS_PGSHIFT);
 102         }
 103         if (NODES_WIDTH) {
 104                 shift -= NODES_WIDTH;
 105                 BUG_ON(shift != NODES_PGSHIFT);
 106         }
 107         if (ZONES_WIDTH) {
 108                 shift -= ZONES_WIDTH;
 109                 BUG_ON(shift != ZONES_PGSHIFT);
 110         }
 111
 112         /* Check for bitmask overlaps */
 113         or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
 114                         (NODES_MASK << NODES_PGSHIFT) |
 115                         (SECTIONS_MASK << SECTIONS_PGSHIFT);
 116         add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
 117                         (NODES_MASK << NODES_PGSHIFT) +
 118                         (SECTIONS_MASK << SECTIONS_PGSHIFT);
 119         BUG_ON(or_mask != add_mask);
 120 }
 121
 122 void __meminit mminit_verify_page_links(struct page *page, enum zone_type zone,
 123                         unsigned long nid, unsigned long pfn)
 124 {
 125         BUG_ON(page_to_nid(page) != nid);
 126         BUG_ON(page_zonenum(page) != zone);
 127         BUG_ON(page_to_pfn(page) != pfn);
 128 }
 129
 130 static __init int set_mminit_loglevel(char *str)
 131 {
 132         get_option(&str, &mminit_loglevel);
 133         return 0;
 134 }
 135 early_param("mminit_loglevel", set_mminit_loglevel);
 136 #endif /* CONFIG_DEBUG_MEMORY_INIT */