xref: /openbmc/linux/mm/mm_init.c (revision ca79522c)
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 - LAST_NID_SHIFT;
73 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
74 		"Section %d Node %d Zone %d Lastnid %d Flags %d\n",
75 		SECTIONS_WIDTH,
76 		NODES_WIDTH,
77 		ZONES_WIDTH,
78 		LAST_NID_WIDTH,
79 		NR_PAGEFLAGS);
80 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
81 		"Section %d Node %d Zone %d Lastnid %d\n",
82 		SECTIONS_SHIFT,
83 		NODES_SHIFT,
84 		ZONES_SHIFT,
85 		LAST_NID_SHIFT);
86 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
87 		"Section %lu Node %lu Zone %lu Lastnid %lu\n",
88 		(unsigned long)SECTIONS_PGSHIFT,
89 		(unsigned long)NODES_PGSHIFT,
90 		(unsigned long)ZONES_PGSHIFT,
91 		(unsigned long)LAST_NID_PGSHIFT);
92 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
93 		"Node/Zone ID: %lu -> %lu\n",
94 		(unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
95 		(unsigned long)ZONEID_PGOFF);
96 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
97 		"location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
98 		shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
99 #ifdef NODE_NOT_IN_PAGE_FLAGS
100 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
101 		"Node not in page flags");
102 #endif
103 #ifdef LAST_NID_NOT_IN_PAGE_FLAGS
104 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
105 		"Last nid not in page flags");
106 #endif
107 
108 	if (SECTIONS_WIDTH) {
109 		shift -= SECTIONS_WIDTH;
110 		BUG_ON(shift != SECTIONS_PGSHIFT);
111 	}
112 	if (NODES_WIDTH) {
113 		shift -= NODES_WIDTH;
114 		BUG_ON(shift != NODES_PGSHIFT);
115 	}
116 	if (ZONES_WIDTH) {
117 		shift -= ZONES_WIDTH;
118 		BUG_ON(shift != ZONES_PGSHIFT);
119 	}
120 
121 	/* Check for bitmask overlaps */
122 	or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
123 			(NODES_MASK << NODES_PGSHIFT) |
124 			(SECTIONS_MASK << SECTIONS_PGSHIFT);
125 	add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
126 			(NODES_MASK << NODES_PGSHIFT) +
127 			(SECTIONS_MASK << SECTIONS_PGSHIFT);
128 	BUG_ON(or_mask != add_mask);
129 }
130 
131 void __meminit mminit_verify_page_links(struct page *page, enum zone_type zone,
132 			unsigned long nid, unsigned long pfn)
133 {
134 	BUG_ON(page_to_nid(page) != nid);
135 	BUG_ON(page_zonenum(page) != zone);
136 	BUG_ON(page_to_pfn(page) != pfn);
137 }
138 
139 static __init int set_mminit_loglevel(char *str)
140 {
141 	get_option(&str, &mminit_loglevel);
142 	return 0;
143 }
144 early_param("mminit_loglevel", set_mminit_loglevel);
145 #endif /* CONFIG_DEBUG_MEMORY_INIT */
146 
147 struct kobject *mm_kobj;
148 EXPORT_SYMBOL_GPL(mm_kobj);
149 
150 static int __init mm_sysfs_init(void)
151 {
152 	mm_kobj = kobject_create_and_add("mm", kernel_kobj);
153 	if (!mm_kobj)
154 		return -ENOMEM;
155 
156 	return 0;
157 }
158 
159 __initcall(mm_sysfs_init);
160