xref: /openbmc/linux/mm/mm_init.c (revision 95e9fd10)
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 "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. */
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 
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 
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 
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 
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