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
15 int mminit_loglevel;
16
17 #ifndef SECTIONS_SHIFT
18 #define SECTIONS_SHIFT 0
19 #endif
20
21 /* The zonelists are simply reported, validation is manual. */
mminit_verify_zonelist(void)22 void 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
mminit_verify_pageflags_layout(void)66 void __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
mminit_verify_page_links(struct page * page,enum zone_type zone,unsigned long nid,unsigned long pfn)124 void __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
set_mminit_loglevel(char * str)132 static __init int set_mminit_loglevel(char *str)
133 {
134 get_option(&str, &mminit_loglevel);
135 return 0;
136 }
137 early_param("mminit_loglevel", set_mminit_loglevel);
138 #endif /* CONFIG_DEBUG_MEMORY_INIT */
139
140 struct kobject *mm_kobj;
141 EXPORT_SYMBOL_GPL(mm_kobj);
142
mm_sysfs_init(void)143 static 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