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